v3: code quality and visual consistency pass (refactored all forms across the app), fixed filename-related upload bug

README.md

@@ -111,21 +111,29 @@ api/
   middleware/      # errorMiddleware, authMiddleware
   routes/          # HTTP routes + WebSocket
   services/        # Business logic
-  model/           # Database schema, row types, type guards
-  lib/             # JWT, pagination, upload helpers, …
-  sql/
+    providers/     # Link metadata providers (YouTube, SoundCloud, Bandcamp, …)
+  model/           # Row types, type guards
+  lib/             # JWT, pagination, slugify, upload, static helpers, …
+  db/
     schema.sql     # Database schema
     init.ts        # First-run database initialisation
+    migrate.ts     # Migration runner
+    migrations/    # Versioned schema migrations
+  sql/
     gerbeur.db     # SQLite database (not committed)
-  uploads/         # User-uploaded files (not committed)
+  uploads/         # User-uploaded files — avatars, dumps, thumbnails, … (not committed)
 src/               # React frontend (Vite)
-  config/api.ts    # API base URL, validation constants
+  config/          # API base URL, validation constants, feed tabs, upload limits
   pages/           # Route-level components
+    index/         # Feed views (hot, new, followed, journal)
   components/      # Shared UI components
+    form/          # Reusable form controls
   contexts/        # Auth, WebSocket, player, follows, theme
   hooks/           # Data fetching and UI hooks
+  utils/           # Formatting, URL, hot-score, waveform, … helpers
   locales/         # Lingui message catalogues (en, fr)
   themes/          # Per-theme CSS files
+  model.ts         # Shared frontend types
   i18n.ts          # Lingui runtime setup
-public/            # Static assets (favicon, icon sprite)
+public/            # Static assets (favicon, manifest, service worker)
 ```

api/routes/files.ts

@@ -5,6 +5,23 @@ import { DUMPS_DIR } from "../lib/upload.ts";
 
 const router = new Router({ prefix: "/api/files" });
 
+/**
+ * Builds an RFC 6266 `Content-Disposition` value that is always a valid
+ * ByteString. `headers.set` throws a TypeError if the value contains any
+ * character > U+00FF, so a filename with an emoji / accent / CJK character
+ * (e.g. an uploaded file) would otherwise crash the response. We provide an
+ * ASCII-only `filename="…"` fallback plus an RFC 5987 `filename*` with the
+ * full UTF-8 name for modern browsers.
+ */
+function contentDisposition(name: string): string {
+  const asciiFallback = name
+    .replace(/["\\]/g, "_")
+    .replace(/[^\x20-\x7e]/g, "_");
+  return `inline; filename="${asciiFallback}"; filename*=UTF-8''${
+    encodeURIComponent(name)
+  }`;
+}
+
 router.get("/:dumpId", async (ctx) => {
   const { dumpId } = ctx.params;
 
@@ -36,7 +53,7 @@ router.get("/:dumpId", async (ctx) => {
   ctx.response.headers.set("Content-Type", dump.fileMime);
   ctx.response.headers.set(
     "Content-Disposition",
-    `inline; filename="${dump.fileName}"`,
+    contentDisposition(dump.fileName),
   );
   ctx.response.headers.set("Accept-Ranges", "bytes");
 

deno.lock

@@ -43,6 +43,7 @@
     "npm:nodemailer@^9.0.1": "9.0.1",
     "npm:path-to-regexp@^6.3.0": "6.3.0",
     "npm:react-dom@^19.2.7": "19.2.7_react@19.2.7",
+    "npm:react-hook-form@^7.80.0": "7.80.0_react@19.2.7",
     "npm:react-markdown@^10.1.0": "10.1.0_@types+react@19.2.17_react@19.2.7",
     "npm:react-router@^8.0.1": "8.0.1_react@19.2.7_react-dom@19.2.7__react@19.2.7",
     "npm:react@^19.2.7": "19.2.7",
@@ -2259,6 +2260,12 @@
         "scheduler"
       ]
     },
+    "react-hook-form@7.80.0_react@19.2.7": {
+      "integrity": "sha512-4P+fk6oXsxY+6xSj7Euhc2sumQD8zQqCuVHoJwoyp9EchP+IUW9OESB7uHFJOKsIBQ4MQqYE84INJFqUCYNoOg==",
+      "dependencies": [
+        "react"
+      ]
+    },
     "react-is@18.3.1": {
       "integrity": "sha512-/LLMVyas0ljjAtoYiPqYiL8VWXzUUdThrmU5+n20DZv+a+ClRoevUzw5JxU+Ieh5/c87ytoTBV9G1FiKfNJdmg=="
     },
@@ -2665,6 +2672,7 @@
         "npm:globals@^17.6.0",
         "npm:jiti@^2.7.0",
         "npm:react-dom@^19.2.7",
+        "npm:react-hook-form@^7.80.0",
         "npm:react-markdown@^10.1.0",
         "npm:react-router@^8.0.1",
         "npm:react@^19.2.7",

package.json

@@ -22,6 +22,7 @@
     "jiti": "^2.7.0",
     "react": "^19.2.7",
     "react-dom": "^19.2.7",
+    "react-hook-form": "^7.80.0",
     "react-markdown": "^10.1.0",
     "react-router": "^8.0.1",
     "remark-gfm": "^4.0.1"

src/App.css

@@ -235,30 +235,31 @@
 }
 
 /* ── Forms ── */
-.auth-form {
+
+/* Unified form system: `.form` container + `.form-field` / `.form-label` /
+   `.form-hint` building blocks, shared by every form. */
+.form {
   display: flex;
   flex-direction: column;
   gap: 1rem;
 }
 
-.dump-form .form-group,
-.auth-form .form-group {
+.form-field {
   display: flex;
   flex-direction: column;
   gap: 0.4rem;
 }
 
-.dump-form label,
-.auth-form label {
+.form-label {
   font-size: 0.85rem;
   font-weight: 600;
   opacity: 0.6;
 }
 
-.dump-form input,
-.dump-form textarea,
-.auth-form input,
-.auth-form textarea {
+.form input,
+.form textarea {
+  width: 100%;
+  box-sizing: border-box;
   padding: 0.65rem 1rem;
   border-radius: 8px;
   border: 2px solid var(--color-border);
@@ -274,15 +275,21 @@
   outline: none;
 }
 
-.dump-form textarea,
-.auth-form textarea {
+/* A submit/secondary button placed as a direct child of `.form` (the auth
+   forms, which have no action row) spans the full width like the inputs.
+   Buttons inside `.form-actions` keep their intrinsic width. */
+.form > .btn-primary,
+.form > .btn-secondary,
+.form > .btn-danger {
+  width: 100%;
+}
+
+.form textarea {
   resize: vertical;
 }
 
-.dump-form input:hover,
-.dump-form textarea:hover,
-.auth-form input:hover,
-.auth-form textarea:hover {
+.form input:hover,
+.form textarea:hover {
   border-color: color-mix(
     in srgb,
     var(--color-accent) 45%,
@@ -290,10 +297,8 @@
   );
 }
 
-.dump-form input:focus,
-.dump-form textarea:focus,
-.auth-form input:focus,
-.auth-form textarea:focus {
+.form input:focus,
+.form textarea:focus {
   border-color: var(--color-accent);
   background-color: color-mix(
     in srgb,
@@ -304,13 +309,27 @@
     color-mix(in srgb, var(--color-accent) 18%, transparent);
 }
 
-.dump-form input:disabled,
-.dump-form textarea:disabled,
-.auth-form input:disabled,
-.auth-form textarea:disabled {
+.form input:disabled,
+.form textarea:disabled {
   opacity: 0.6;
 }
 
+.form-hint {
+  font-size: 0.8rem;
+  opacity: 0.7;
+  margin-top: 0.1rem;
+}
+
+.form-hint--error {
+  color: var(--color-error, #c0392b);
+  opacity: 1;
+}
+
+.form-success {
+  color: var(--color-success, green);
+  margin: 0;
+}
+
 .dump-create-title-row {
   display: flex;
   align-items: center;
@@ -2308,16 +2327,6 @@ body.has-player .fab-new {
   opacity: 0.85;
 }
 
-.auth-field-hint {
-  display: block;
-  font-size: 0.8rem;
-  margin-top: 0.25rem;
-}
-
-.auth-field-hint--error {
-  color: var(--color-error, #e53e3e);
-}
-
 /* ── Form pages (DumpCreate / DumpEdit) ── */
 @keyframes page-enter {
   from {
@@ -2348,7 +2357,9 @@ body.has-player .fab-new {
   .form-page--two-col .dump-edit-preview {
     border-radius: 0 0 0 12px;
   }
-  .form-page--two-col .dump-form {
+  /* Higher specificity than the generic `.form-page .form` below so the
+     form's bottom-left stays square where it meets the preview. */
+  .form-page.form-page--two-col .form {
     border-radius: 0 0 12px 0;
   }
 }
@@ -2395,10 +2406,7 @@ body.has-player .fab-new {
   gap: 0.75rem;
 }
 
-.dump-form {
-  display: flex;
-  flex-direction: column;
-  gap: 1rem;
+.form-page .form {
   background: var(--color-surface);
   border-radius: 0 0 12px 12px;
   padding: 1.25rem;
@@ -2421,7 +2429,13 @@ body.has-player .fab-new {
   margin-left: auto;
 }
 
+/* Subtle text action. Resets the global <button> chrome so it looks the same
+   whether rendered as a <button> (modal/page forms) or a <Link> (DumpEdit). */
 .form-cancel {
+  background: none;
+  border: none;
+  padding: 0;
+  cursor: pointer;
   font-size: 0.9rem;
   color: var(--color-text);
   opacity: 0.6;
@@ -3189,30 +3203,6 @@ body.has-player .fab-new {
   background: color-mix(in srgb, var(--color-accent) 8%, transparent);
 }
 
-.modal-new-playlist-form {
-  display: flex;
-  flex-direction: column;
-  gap: 0.6rem;
-}
-
-.modal-new-playlist-form input,
-.modal-new-playlist-form textarea {
-  padding: 0.6rem 0.9rem;
-  border-radius: 8px;
-  border: 2px solid var(--color-border-subtle);
-  background: var(--color-bg);
-  color: var(--color-text);
-  font-size: 0.95rem;
-  font-family: inherit;
-  outline: none;
-  transition: border-color 0.2s;
-  resize: vertical;
-}
-
-.modal-new-playlist-form input:focus,
-.modal-new-playlist-form textarea:focus {
-  border-color: var(--color-accent);
-}
 
 /* ── Playlist detail page ── */
 .playlist-detail-header {
@@ -3341,6 +3331,12 @@ body.has-player .fab-new {
   font-weight: 700;
 }
 
+/* Inline edit form: stack the fields with a little more breathing room than
+   the tight display layout, and let the action row sit at the bottom. */
+.playlist-edit-content {
+  gap: 0.7rem;
+}
+
 .playlist-edit-input:focus,
 .playlist-edit-textarea:focus {
   border-color: var(--color-accent);

src/components/ChangePasswordModal.tsx

@@ -3,183 +3,106 @@ import { t } from "@lingui/core/macro";
 import { Trans } from "@lingui/react/macro";
 import { API_URL, VALIDATION } from "../config/api.ts";
 import { useAuth } from "../hooks/useAuth.ts";
-import { ErrorCard } from "./ErrorCard.tsx";
 import { Modal } from "./Modal.tsx";
+import {
+  expectOk,
+  FormActions,
+  FormError,
+  FormProvider,
+  SubmitButton,
+  TextField,
+  useApiForm,
+} from "./form/index.ts";
 
 interface ChangePasswordModalProps {
   onClose: () => void;
 }
 
+interface Values {
+  currentPassword: string;
+  newPassword: string;
+  confirmPassword: string;
+}
+
 export function ChangePasswordModal({ onClose }: ChangePasswordModalProps) {
   const { authFetch } = useAuth();
-  const [currentPassword, setCurrentPassword] = useState("");
-  const [newPassword, setNewPassword] = useState("");
-  const [confirmPassword, setConfirmPassword] = useState("");
-  const [submitting, setSubmitting] = useState(false);
-  const [error, setError] = useState<string | null>(null);
   const [done, setDone] = useState(false);
+  const form = useApiForm<Values>({
+    mode: "onChange",
+    defaultValues: { currentPassword: "", newPassword: "", confirmPassword: "" },
+  });
 
-  const mismatch = confirmPassword.length > 0 &&
-    newPassword !== confirmPassword;
-  const tooShort = newPassword.length > 0 &&
-    newPassword.length < VALIDATION.PASSWORD_MIN;
-
-  const handleSubmit = async (e: React.SubmitEvent) => {
-    e.preventDefault();
-    if (mismatch || tooShort || !currentPassword || !newPassword) return;
-
-    setSubmitting(true);
-    setError(null);
-    try {
-      const res = await authFetch(
-        `${API_URL}/api/users/me/change-password`,
-        {
-          method: "POST",
-          headers: { "Content-Type": "application/json" },
-          body: JSON.stringify({ currentPassword, newPassword }),
-        },
-      );
-      const body = await res.json();
-      if (!body.success) {
-        setError(body.error?.message ?? t`Unknown error`);
-        return;
-      }
-      setDone(true);
-    } catch {
-      setError(t`Failed to change password`);
-    } finally {
-      setSubmitting(false);
-    }
-  };
+  const onSubmit = form.submit(async ({ currentPassword, newPassword }) => {
+    await expectOk(
+      await authFetch(`${API_URL}/api/users/me/change-password`, {
+        method: "POST",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ currentPassword, newPassword }),
+      }),
+    );
+    setDone(true);
+  });
 
   return (
     <Modal title={t`Change password`} onClose={onClose}>
       {done
         ? (
-          <div className="modal-new-playlist-form">
-            <p style={{ color: "var(--color-success, green)" }}>
+          <div className="form">
+            <p className="form-success">
               <Trans>Password changed successfully.</Trans>
             </p>
-            <div className="form-actions">
-              <div className="form-actions-right">
-                <button type="button" className="btn-primary" onClick={onClose}>
-                  <Trans>Close</Trans>
-                </button>
-              </div>
-            </div>
+            <FormActions>
+              <button type="button" className="btn-primary" onClick={onClose}>
+                <Trans>Close</Trans>
+              </button>
+            </FormActions>
           </div>
         )
         : (
-          <form className="modal-new-playlist-form" onSubmit={handleSubmit}>
-            <label>
-              <span
-                style={{
-                  display: "block",
-                  marginBottom: "0.25rem",
-                  fontSize: "0.85rem",
-                  opacity: 0.7,
-                }}
-              >
-                <Trans>Current password</Trans>
-              </span>
-              <input
+          <FormProvider {...form}>
+            <form className="form" onSubmit={onSubmit}>
+              <TextField<Values>
+                name="currentPassword"
                 type="password"
-                value={currentPassword}
-                onChange={(e) => setCurrentPassword(e.target.value)}
+                label={t`Current password`}
                 autoComplete="current-password"
-                required
                 autoFocus
+                rules={{ required: true }}
               />
-            </label>
-            <label>
-              <span
-                style={{
-                  display: "block",
-                  marginBottom: "0.25rem",
-                  fontSize: "0.85rem",
-                  opacity: 0.7,
-                }}
-              >
-                <Trans>New password</Trans>
-              </span>
-              <input
+              <TextField<Values>
+                name="newPassword"
                 type="password"
-                value={newPassword}
-                onChange={(e) => setNewPassword(e.target.value)}
+                label={t`New password`}
                 autoComplete="new-password"
-                minLength={VALIDATION.PASSWORD_MIN}
                 maxLength={VALIDATION.PASSWORD_MAX}
-                required
-              />
-              {tooShort && (
-                <span
-                  style={{
-                    fontSize: "0.8rem",
-                    color: "var(--color-error, red)",
-                    marginTop: "0.2rem",
-                    display: "block",
-                  }}
-                >
-                  <Trans>At least {VALIDATION.PASSWORD_MIN} characters</Trans>
-                </span>
-              )}
-            </label>
-            <label>
-              <span
-                style={{
-                  display: "block",
-                  marginBottom: "0.25rem",
-                  fontSize: "0.85rem",
-                  opacity: 0.7,
+                rules={{
+                  required: true,
+                  minLength: {
+                    value: VALIDATION.PASSWORD_MIN,
+                    message: t`At least ${VALIDATION.PASSWORD_MIN} characters`,
+                  },
                 }}
-              >
-                <Trans>Confirm new password</Trans>
-              </span>
-              <input
-                type="password"
-                value={confirmPassword}
-                onChange={(e) => setConfirmPassword(e.target.value)}
-                autoComplete="new-password"
-                required
               />
-              {mismatch && (
-                <span
-                  style={{
-                    fontSize: "0.8rem",
-                    color: "var(--color-error, red)",
-                    marginTop: "0.2rem",
-                    display: "block",
-                  }}
-                >
-                  <Trans>Passwords do not match</Trans>
-                </span>
-              )}
-            </label>
-            {error && (
-              <ErrorCard title={t`Could not change password`} message={error} />
-            )}
-            <div className="form-actions">
-              <div className="form-actions-right">
-                <button
-                  type="button"
-                  className="form-cancel"
-                  onClick={onClose}
-                >
-                  <Trans>Cancel</Trans>
-                </button>
-                <button
-                  type="submit"
-                  className="btn-primary"
-                  disabled={submitting || mismatch || tooShort ||
-                    !currentPassword || !newPassword || !confirmPassword}
-                >
-                  {submitting
-                    ? <Trans>Saving…</Trans>
-                    : <Trans>Change password</Trans>}
-                </button>
-              </div>
-            </div>
-          </form>
+              <TextField<Values>
+                name="confirmPassword"
+                type="password"
+                label={t`Confirm new password`}
+                autoComplete="new-password"
+                rules={{
+                  required: true,
+                  validate: (value, values) =>
+                    value === values.newPassword ||
+                    t`Passwords do not match`,
+                }}
+              />
+              <FormError title={t`Could not change password`} />
+              <FormActions onCancel={onClose}>
+                <SubmitButton pendingLabel={<Trans>Saving…</Trans>}>
+                  <Trans>Change password</Trans>
+                </SubmitButton>
+              </FormActions>
+            </form>
+          </FormProvider>
         )}
     </Modal>
   );

src/components/CommentThread.tsx

@@ -1,5 +1,6 @@
 import React, { useMemo, useRef, useState } from "react";
 import { Link } from "react-router";
+import { Controller } from "react-hook-form";
 import { t } from "@lingui/core/macro";
 import { Plural, Trans } from "@lingui/react/macro";
 import { API_URL, VALIDATION } from "../config/api.ts";
@@ -10,16 +11,141 @@ import type {
   UpdateCommentRequest,
   User,
 } from "../model.ts";
-import { deserializeComment, parseAPIResponse } from "../model.ts";
+import { deserializeComment } from "../model.ts";
 import { Avatar } from "./Avatar.tsx";
 import { Markdown } from "./Markdown.tsx";
 import { TextEditor, type TextEditorHandle } from "./TextEditor.tsx";
 import { LikeButton } from "./LikeButton.tsx";
 import { relativeTime } from "../utils/relativeTime.ts";
-import { ErrorCard } from "./ErrorCard.tsx";
 import { Tooltip } from "./Tooltip.tsx";
 import { ConfirmModal } from "./ConfirmModal.tsx";
 import { useWS } from "../hooks/useWS.ts";
+import {
+  expectOk,
+  FormError,
+  FormProvider,
+  SubmitButton,
+  useApiForm,
+} from "./form/index.ts";
+
+function authHeaders(token: string | null, json = true): HeadersInit {
+  const headers: Record<string, string> = {};
+  if (json) headers["Content-Type"] = "application/json";
+  if (token) headers["Authorization"] = `Bearer ${token}`;
+  return headers;
+}
+
+interface CommentFormProps {
+  /** Async submit; throw to surface a root error, resolve to clear/close. */
+  onSubmit: (body: string) => Promise<void>;
+  submitLabel: React.ReactNode;
+  pendingLabel: React.ReactNode;
+  errorTitle: string;
+  placeholder?: string;
+  defaultValue?: string;
+  onCancel?: () => void;
+  /** Top-level form: only show Cancel once there's text to discard. */
+  cancelWhenEmpty?: boolean;
+  editorRef?: React.Ref<TextEditorHandle>;
+  /** `top` renders the avatar-flanked layout; `inline` is for reply/edit. */
+  layout?: "inline" | "top";
+  leading?: React.ReactNode;
+}
+
+/**
+ * Single-field comment editor (post / reply / edit). Wraps the shared
+ * react-hook-form lifecycle so the three call sites stay identical.
+ */
+function CommentForm({
+  onSubmit,
+  submitLabel,
+  pendingLabel,
+  errorTitle,
+  placeholder,
+  defaultValue = "",
+  onCancel,
+  cancelWhenEmpty,
+  editorRef,
+  layout = "inline",
+  leading,
+}: CommentFormProps) {
+  const form = useApiForm<{ body: string }>({
+    defaultValues: { body: defaultValue },
+  });
+  const body = form.watch("body");
+  const disabled = !body.trim() || body.length > VALIDATION.COMMENT_BODY_MAX;
+
+  const submit = form.submit(async ({ body }) => {
+    if (!body.trim() || body.length > VALIDATION.COMMENT_BODY_MAX) return;
+    await onSubmit(body);
+    form.reset({ body: "" });
+  });
+
+  const showCancel = onCancel && (!cancelWhenEmpty || body.trim().length > 0);
+
+  const inner = (
+    <>
+      <Controller
+        name="body"
+        control={form.control}
+        render={({ field }) => (
+          <TextEditor
+            ref={editorRef}
+            className="comment-reply-textarea"
+            value={field.value}
+            onChange={field.onChange}
+            onSubmit={() => void submit()}
+            placeholder={placeholder}
+            autoResize
+            rows={1}
+            maxLength={VALIDATION.COMMENT_BODY_MAX}
+          />
+        )}
+      />
+      <FormError title={errorTitle} />
+      <div className="comment-form-actions">
+        <SubmitButton
+          className="comment-submit-btn"
+          pendingLabel={pendingLabel}
+          disabled={disabled}
+        >
+          {submitLabel}
+        </SubmitButton>
+        {showCancel && (
+          <button
+            type="button"
+            className="comment-cancel-btn"
+            onClick={() => {
+              form.reset({ body: "" });
+              onCancel?.();
+            }}
+          >
+            <Trans>Cancel</Trans>
+          </button>
+        )}
+      </div>
+    </>
+  );
+
+  return (
+    <FormProvider {...form}>
+      {layout === "top"
+        ? (
+          <form className="comment-top-form" onSubmit={submit}>
+            <div className="comment-top-form-inner">
+              {leading}
+              <div className="comment-top-form-body">{inner}</div>
+            </div>
+          </form>
+        )
+        : (
+          <form className="comment-form" onSubmit={submit}>
+            {inner}
+          </form>
+        )}
+    </FormProvider>
+  );
+}
 
 interface CommentThreadProps {
   dumpId: string;
@@ -65,14 +191,8 @@ function CommentNode({
   onCommentUpdated,
 }: CommentNodeProps) {
   const [replyOpen, setReplyOpen] = useState(false);
-  const [replyBody, setReplyBody] = useState("");
-  const [submitting, setSubmitting] = useState(false);
-  const [replyError, setReplyError] = useState<string | null>(null);
   const [editOpen, setEditOpen] = useState(false);
-  const [editBody, setEditBody] = useState("");
   const [confirmDelete, setConfirmDelete] = useState(false);
-  const [editSubmitting, setEditSubmitting] = useState(false);
-  const [editError, setEditError] = useState<string | null>(null);
 
   const replyEditorRef = useRef<TextEditorHandle>(null);
   const editEditorRef = useRef<TextEditorHandle>(null);
@@ -81,41 +201,16 @@ function CommentNode({
 
   const children = tree.get(comment.id) ?? [];
 
-  async function handleReply(e?: React.SubmitEvent) {
-    e?.preventDefault();
-    if (
-      !replyBody.trim() || !token ||
-      replyBody.length > VALIDATION.COMMENT_BODY_MAX
-    ) return;
-    setSubmitting(true);
-    setReplyError(null);
-    try {
-      const res = await fetch(`${API_URL}/api/dumps/${dumpId}/comments`, {
-        method: "POST",
-        headers: {
-          "Content-Type": "application/json",
-          Authorization: `Bearer ${token}`,
-        },
-        body: JSON.stringify(
-          {
-            body: replyBody,
-            parentId: comment.id,
-          } satisfies CreateCommentRequest,
-        ),
-      });
-      const data = parseAPIResponse<RawComment>(await res.json());
-      if (data.success) {
-        onCommentCreated(deserializeComment(data.data));
-        setReplyBody("");
-        setReplyOpen(false);
-      } else {
-        setReplyError(data.error.message);
-      }
-    } catch {
-      setReplyError(t`Could not reach the server. Please try again.`);
-    } finally {
-      setSubmitting(false);
-    }
+  async function handleReply(body: string) {
+    const res = await fetch(`${API_URL}/api/dumps/${dumpId}/comments`, {
+      method: "POST",
+      headers: authHeaders(token),
+      body: JSON.stringify(
+        { body, parentId: comment.id } satisfies CreateCommentRequest,
+      ),
+    });
+    onCommentCreated(deserializeComment(await expectOk<RawComment>(res)));
+    setReplyOpen(false);
   }
 
   async function handleDelete() {
@@ -129,35 +224,14 @@ function CommentNode({
     }
   }
 
-  async function handleEditSave(e?: React.SubmitEvent) {
-    e?.preventDefault();
-    if (
-      !editBody.trim() || !token ||
-      editBody.length > VALIDATION.COMMENT_BODY_MAX
-    ) return;
-    setEditSubmitting(true);
-    setEditError(null);
-    try {
-      const res = await fetch(`${API_URL}/api/comments/${comment.id}`, {
-        method: "PATCH",
-        headers: {
-          "Content-Type": "application/json",
-          Authorization: `Bearer ${token}`,
-        },
-        body: JSON.stringify({ body: editBody } satisfies UpdateCommentRequest),
-      });
-      const data = parseAPIResponse<RawComment>(await res.json());
-      if (data.success) {
-        onCommentUpdated(deserializeComment(data.data));
-        setEditOpen(false);
-      } else {
-        setEditError(data.error.message);
-      }
-    } catch {
-      setEditError(t`Could not reach the server. Please try again.`);
-    } finally {
-      setEditSubmitting(false);
-    }
+  async function handleEditSave(body: string) {
+    const res = await fetch(`${API_URL}/api/comments/${comment.id}`, {
+      method: "PATCH",
+      headers: authHeaders(token),
+      body: JSON.stringify({ body } satisfies UpdateCommentRequest),
+    });
+    onCommentUpdated(deserializeComment(await expectOk<RawComment>(res)));
+    setEditOpen(false);
   }
 
   const canDelete = !comment.deleted && !!currentUser &&
@@ -245,47 +319,15 @@ function CommentNode({
           </div>
           {editOpen
             ? (
-              <form className="comment-form" onSubmit={handleEditSave}>
-                <TextEditor
-                  ref={editEditorRef}
-                  className="comment-reply-textarea"
-                  value={editBody}
-                  onChange={setEditBody}
-                  onSubmit={handleEditSave}
-                  autoResize
-                  rows={1}
-                  maxLength={VALIDATION.COMMENT_BODY_MAX}
-                />
-                {editError && (
-                  <ErrorCard
-                    title={t`Failed to save edit`}
-                    message={editError}
-                  />
-                )}
-                <div className="comment-form-actions">
-                  <button
-                    type="submit"
-                    className="comment-submit-btn"
-                    disabled={editSubmitting || !editBody.trim() ||
-                      editBody.length > VALIDATION.COMMENT_BODY_MAX}
-                  >
-                    {editSubmitting
-                      ? <Trans>Saving…</Trans>
-                      : <Trans>Save</Trans>}
-                  </button>
-                  <button
-                    type="button"
-                    className="comment-cancel-btn"
-                    onClick={() => {
-                      setEditOpen(false);
-                      setEditBody("");
-                      setEditError(null);
-                    }}
-                  >
-                    <Trans>Cancel</Trans>
-                  </button>
-                </div>
-              </form>
+              <CommentForm
+                editorRef={editEditorRef}
+                defaultValue={comment.body}
+                onSubmit={handleEditSave}
+                submitLabel={<Trans>Save</Trans>}
+                pendingLabel={<Trans>Saving…</Trans>}
+                errorTitle={t`Failed to save edit`}
+                onCancel={() => setEditOpen(false)}
+              />
             )
             : <Markdown className="comment-body">{comment.body}</Markdown>}
           <div className="comment-actions">
@@ -316,7 +358,6 @@ function CommentNode({
                 type="button"
                 className="comment-action-btn"
                 onClick={() => {
-                  setEditBody(comment.body);
                   setEditOpen(true);
                   setTimeout(() => editEditorRef.current?.focus(), 0);
                 }}
@@ -346,48 +387,15 @@ function CommentNode({
             )}
           </div>
           {replyOpen && (
-            <form className="comment-form" onSubmit={handleReply}>
-              <TextEditor
-                ref={replyEditorRef}
-                className="comment-reply-textarea"
-                value={replyBody}
-                onChange={setReplyBody}
-                onSubmit={handleReply}
-                placeholder={t`Write a reply…`}
-                autoResize
-                rows={1}
-                maxLength={VALIDATION.COMMENT_BODY_MAX}
-              />
-              {replyError && (
-                <ErrorCard
-                  title={t`Failed to post reply`}
-                  message={replyError}
-                />
-              )}
-              <div className="comment-form-actions">
-                <button
-                  type="submit"
-                  className="comment-submit-btn"
-                  disabled={submitting || !replyBody.trim() ||
-                    replyBody.length > VALIDATION.COMMENT_BODY_MAX}
-                >
-                  {submitting
-                    ? <Trans>Posting…</Trans>
-                    : <Trans>Post reply</Trans>}
-                </button>
-                <button
-                  type="button"
-                  className="comment-cancel-btn"
-                  onClick={() => {
-                    setReplyOpen(false);
-                    setReplyBody("");
-                    setReplyError(null);
-                  }}
-                >
-                  <Trans>Cancel</Trans>
-                </button>
-              </div>
-            </form>
+            <CommentForm
+              editorRef={replyEditorRef}
+              onSubmit={handleReply}
+              submitLabel={<Trans>Post reply</Trans>}
+              pendingLabel={<Trans>Posting…</Trans>}
+              errorTitle={t`Failed to post reply`}
+              placeholder={t`Write a reply…`}
+              onCancel={() => setReplyOpen(false)}
+            />
           )}
         </div>
       </div>
@@ -425,44 +433,16 @@ export function CommentThread({
   onCommentDeleted,
   onCommentUpdated,
 }: CommentThreadProps) {
-  const [topLevelBody, setTopLevelBody] = useState("");
-  const [submitting, setSubmitting] = useState(false);
-  const [topLevelError, setTopLevelError] = useState<string | null>(null);
-
   const tree = useMemo(() => buildTree(comments), [comments]);
   const roots = tree.get("root") ?? [];
 
-  async function handleTopLevelSubmit(e?: React.SubmitEvent) {
-    e?.preventDefault();
-    if (
-      !topLevelBody.trim() || !token ||
-      topLevelBody.length > VALIDATION.COMMENT_BODY_MAX
-    ) return;
-    setSubmitting(true);
-    setTopLevelError(null);
-    try {
-      const res = await fetch(`${API_URL}/api/dumps/${dumpId}/comments`, {
-        method: "POST",
-        headers: {
-          "Content-Type": "application/json",
-          Authorization: `Bearer ${token}`,
-        },
-        body: JSON.stringify(
-          { body: topLevelBody } satisfies CreateCommentRequest,
-        ),
-      });
-      const data = parseAPIResponse<RawComment>(await res.json());
-      if (data.success) {
-        onCommentCreated(deserializeComment(data.data));
-        setTopLevelBody("");
-      } else {
-        setTopLevelError(data.error.message);
-      }
-    } catch {
-      setTopLevelError(t`Could not reach the server. Please try again.`);
-    } finally {
-      setSubmitting(false);
-    }
+  async function handleTopLevelSubmit(body: string) {
+    const res = await fetch(`${API_URL}/api/dumps/${dumpId}/comments`, {
+      method: "POST",
+      headers: authHeaders(token),
+      body: JSON.stringify({ body } satisfies CreateCommentRequest),
+    });
+    onCommentCreated(deserializeComment(await expectOk<RawComment>(res)));
   }
 
   const visibleCount = comments.filter((c) => !c.deleted).length;
@@ -474,8 +454,9 @@ export function CommentThread({
       </h2>
 
       {currentUser && (
-        <form className="comment-top-form" onSubmit={handleTopLevelSubmit}>
-          <div className="comment-top-form-inner">
+        <CommentForm
+          layout="top"
+          leading={
             <div className="comment-avatar">
               <Avatar
                 userId={currentUser.id}
@@ -484,50 +465,15 @@ export function CommentThread({
                 size={28}
               />
             </div>
-            <div className="comment-top-form-body">
-              <TextEditor
-                className="comment-reply-textarea"
-                value={topLevelBody}
-                onChange={setTopLevelBody}
-                onSubmit={handleTopLevelSubmit}
-                placeholder={t`Add a comment…`}
-                autoResize
-                rows={1}
-                maxLength={VALIDATION.COMMENT_BODY_MAX}
-              />
-              {topLevelError && (
-                <ErrorCard
-                  title={t`Failed to post comment`}
-                  message={topLevelError}
-                />
-              )}
-              <div className="comment-form-actions">
-                <button
-                  type="submit"
-                  className="comment-submit-btn"
-                  disabled={submitting || !topLevelBody.trim() ||
-                    topLevelBody.length > VALIDATION.COMMENT_BODY_MAX}
-                >
-                  {submitting
-                    ? <Trans>Posting…</Trans>
-                    : <Trans>Post comment</Trans>}
-                </button>
-                {topLevelBody.trim() && (
-                  <button
-                    type="button"
-                    className="comment-cancel-btn"
-                    onClick={() => {
-                      setTopLevelBody("");
-                      setTopLevelError(null);
-                    }}
-                  >
-                    <Trans>Cancel</Trans>
-                  </button>
-                )}
-              </div>
-            </div>
-          </div>
-        </form>
+          }
+          onSubmit={handleTopLevelSubmit}
+          submitLabel={<Trans>Post comment</Trans>}
+          pendingLabel={<Trans>Posting…</Trans>}
+          errorTitle={t`Failed to post comment`}
+          placeholder={t`Add a comment…`}
+          onCancel={() => {}}
+          cancelWhenEmpty
+        />
       )}
 
       {roots.length > 0 && (

src/components/ConfirmModal.tsx

@@ -28,7 +28,7 @@ export function ConfirmModal(
       <div className="confirm-modal" onClick={(e) => e.stopPropagation()}>
         <p className="confirm-modal-message">{message}</p>
         <div className="confirm-modal-actions">
-          <button type="button" onClick={onCancel}>
+          <button type="button" className="btn-secondary" onClick={onCancel}>
             <Trans>Cancel</Trans>
           </button>
           <button type="button" className="btn-danger" onClick={onConfirm}>

src/components/DumpCreateModal.tsx

@@ -1,5 +1,6 @@
 import { useEffect, useRef, useState } from "react";
 import { Link } from "react-router";
+import { Controller } from "react-hook-form";
 import { t } from "@lingui/core/macro";
 import { Trans } from "@lingui/react/macro";
 
@@ -14,7 +15,6 @@ import type {
 import {
   deserializeDump,
   deserializePlaylistMembership,
-  parseAPIResponse,
 } from "../model.ts";
 import { useAuth } from "../hooks/useAuth.ts";
 import { useWS } from "../hooks/useWS.ts";
@@ -23,26 +23,36 @@ import { MAX_FILE_SIZE } from "../config/upload.ts";
 import RichContentCard from "./RichContentCard.tsx";
 import { MediaPlayer } from "./MediaPlayer.tsx";
 import type { RichContent } from "../model.ts";
-import { ErrorCard } from "./ErrorCard.tsx";
 import { FileDropZone } from "./FileDropZone.tsx";
-import { TextEditor } from "./TextEditor.tsx";
 import { Modal } from "./Modal.tsx";
 import { PlaylistMembershipPanel } from "./PlaylistMembershipPanel.tsx";
-import { friendlyFetchError } from "../utils/apiError.ts";
+import {
+  expectOk,
+  FormActions,
+  FormError,
+  FormProvider,
+  RichTextField,
+  SubmitButton,
+  useApiForm,
+  VisibilityToggle,
+} from "./form/index.ts";
 
 type Mode = "url" | "file";
 type Phase = "create" | "playlist";
 
-type SubmitState =
-  | { status: "idle" }
-  | { status: "submitting" }
-  | { status: "error"; error: string };
-
 type UrlPreview =
   | { status: "idle" }
   | { status: "loading" }
   | { status: "done"; richContent: RichContent | null };
 
+interface CreateValues {
+  url: string;
+  file: File | null;
+  title: string;
+  comment: string;
+  isPublic: boolean;
+}
+
 function LocalFilePreview({ file }: { file: File }) {
   const [src, setSrc] = useState<string | null>(null);
 
@@ -86,28 +96,34 @@ export function DumpCreateModal(
 
   // Create phase state
   const [mode, setMode] = useState<Mode>("url");
-  const [url, setUrl] = useState(initialUrl);
-  const [file, setFile] = useState<File | null>(null);
-  const [title, setTitle] = useState("");
   const [titleEditing, setTitleEditing] = useState(false);
   const titleInputRef = useRef<HTMLInputElement | null>(null);
-  const [comment, setComment] = useState("");
-  const [isPrivate, setIsPrivate] = useState(false);
-  const [submitState, setSubmitState] = useState<SubmitState>({
-    status: "idle",
-  });
   const [urlFetchState, setUrlFetchState] = useState<UrlPreview>({
     status: "idle",
   });
   const debounceRef = useRef<ReturnType<typeof setTimeout> | null>(null);
 
+  const form = useApiForm<CreateValues>({
+    defaultValues: {
+      url: initialUrl,
+      file: null,
+      title: "",
+      comment: "",
+      isPublic: true,
+    },
+  });
+  const { register, setValue, watch, clearErrors, control } = form;
+  const submitting = form.formState.isSubmitting;
+  const url = watch("url");
+  const file = watch("file");
+
   // Playlist phase state
   const [memberships, setMemberships] = useState<PlaylistMembership[]>([]);
   const [playlistsLoading, setPlaylistsLoading] = useState(false);
 
   const selectFile = (f: File | null) => {
-    setFile(f);
-    setTitle(f?.name ?? "");
+    setValue("file", f);
+    setValue("title", f?.name ?? "");
     setTitleEditing(false);
   };
 
@@ -166,9 +182,9 @@ export function DumpCreateModal(
       const pastedFile = e.clipboardData?.files[0];
       if (pastedFile) {
         setMode("file");
-        setUrl("");
+        setValue("url", "");
         selectFile(pastedFile);
-        setSubmitState({ status: "idle" });
+        clearErrors("root");
         return;
       }
       const tag = (e.target as HTMLElement).tagName;
@@ -179,95 +195,71 @@ export function DumpCreateModal(
         if (u.protocol === "http:" || u.protocol === "https:") {
           setMode("url");
           selectFile(null);
-          setUrl(u.toString());
-          setSubmitState({ status: "idle" });
+          setValue("url", u.toString());
+          clearErrors("root");
         }
       } catch { /* not a URL */ }
     };
     globalThis.addEventListener("paste", handler);
     return () => globalThis.removeEventListener("paste", handler);
+    // setValue/clearErrors are stable RHF refs; selectFile closes over them.
   }, []);
 
-  const handleSubmit = async (e: React.SubmitEvent) => {
-    e.preventDefault();
-    if (comment.length > VALIDATION.DUMP_COMMENT_MAX) return;
-    setSubmitState({ status: "submitting" });
+  const onSubmit = form.submit(async (
+    { url, file, title, comment, isPublic },
+  ) => {
+    const isPrivate = !isPublic;
+    let res: Response;
 
-    try {
-      let res: Response;
-
-      if (mode === "url") {
-        const normalizedUrl = normalizeUrl(url);
-        if (!normalizedUrl) {
-          setSubmitState({ status: "error", error: t`URL is required.` });
-          return;
-        }
-        setUrl(normalizedUrl);
-        const body: CreateUrlDumpRequest = {
-          url: normalizedUrl,
-          comment: comment.trim() || undefined,
-          isPrivate,
-        };
-        res = await authFetch(`${API_URL}/api/dumps`, {
-          method: "POST",
-          body: JSON.stringify(body),
-        });
-      } else {
-        if (!file) {
-          setSubmitState({
-            status: "error",
-            error: t`Please select a file.`,
-          });
-          return;
-        }
-        if (file.size > MAX_FILE_SIZE) {
-          setSubmitState({
-            status: "error",
-            error: t`File too large (max 50 MB).`,
-          });
-          return;
-        }
-        const formData = new FormData();
-        formData.append("file", file);
-        if (comment.trim()) formData.append("comment", comment.trim());
-        if (title.trim()) formData.append("title", title.trim());
-        formData.append("isPrivate", String(isPrivate));
-        res = await authFetch(`${API_URL}/api/dumps`, {
-          method: "POST",
-          body: formData,
-        });
+    if (mode === "url") {
+      const normalizedUrl = normalizeUrl(url);
+      if (!normalizedUrl) throw new Error(t`URL is required.`);
+      setValue("url", normalizedUrl);
+      const body: CreateUrlDumpRequest = {
+        url: normalizedUrl,
+        comment: comment.trim() || undefined,
+        isPrivate,
+      };
+      res = await authFetch(`${API_URL}/api/dumps`, {
+        method: "POST",
+        body: JSON.stringify(body),
+      });
+    } else {
+      if (!file) throw new Error(t`Please select a file.`);
+      if (!title.trim()) throw new Error(t`Title is required.`);
+      if (file.size > MAX_FILE_SIZE) {
+        throw new Error(t`File too large (max 50 MB).`);
       }
-
-      const apiResponse = parseAPIResponse<RawDump>(await res.json());
-      if (apiResponse.success) {
-        const dump = deserializeDump(apiResponse.data);
-        injectDump(dump);
-        setCreatedDump(dump);
-        setPhase("playlist");
-        setPlaylistsLoading(true);
-        authFetch(`${API_URL}/api/playlists/by-dump/${dump.id}/memberships`)
-          .then((r) => r.json())
-          .then((body) => {
-            if (body.success) {
-              setMemberships(
-                (body.data as RawPlaylistMembership[]).map(
-                  deserializePlaylistMembership,
-                ),
-              );
-            }
-          })
-          .catch(() => {})
-          .finally(() => setPlaylistsLoading(false));
-      } else {
-        setSubmitState({
-          status: "error",
-          error: apiResponse.error.message,
-        });
-      }
-    } catch (err) {
-      setSubmitState({ status: "error", error: friendlyFetchError(err) });
+      const formData = new FormData();
+      formData.append("file", file);
+      if (comment.trim()) formData.append("comment", comment.trim());
+      if (title.trim()) formData.append("title", title.trim());
+      formData.append("isPrivate", String(isPrivate));
+      res = await authFetch(`${API_URL}/api/dumps`, {
+        method: "POST",
+        body: formData,
+      });
     }
-  };
+
+    const dump = deserializeDump(await expectOk<RawDump>(res));
+    injectDump(dump);
+    setCreatedDump(dump);
+    setPhase("playlist");
+    setPlaylistsLoading(true);
+    authFetch(`${API_URL}/api/playlists/by-dump/${dump.id}/memberships`)
+      .then((r) => r.json())
+      .then((body) => {
+        if (body.success) {
+          setMemberships(
+            (body.data as RawPlaylistMembership[]).map(
+              deserializePlaylistMembership,
+            ),
+          );
+        }
+      })
+      .catch(() => {})
+      .finally(() => setPlaylistsLoading(false));
+  });
 
   const toggleMembership = async (membership: PlaylistMembership) => {
     if (!createdDump) return;
@@ -295,8 +287,6 @@ export function DumpCreateModal(
     }
   };
 
-  const submitting = submitState.status === "submitting";
-
   return (
     <Modal
       title={phase === "create" ? t`New dump` : t`Add to playlist`}
@@ -313,7 +303,7 @@ export function DumpCreateModal(
                 onClick={() => {
                   setMode("url");
                   selectFile(null);
-                  setSubmitState({ status: "idle" });
+                  clearErrors("root");
                 }}
                 disabled={submitting}
               >
@@ -324,8 +314,8 @@ export function DumpCreateModal(
                 className={mode === "file" ? "active" : ""}
                 onClick={() => {
                   setMode("file");
-                  setUrl("");
-                  setSubmitState({ status: "idle" });
+                  setValue("url", "");
+                  clearErrors("root");
                 }}
                 disabled={submitting}
               >
@@ -333,161 +323,134 @@ export function DumpCreateModal(
               </button>
             </div>
 
-            <form onSubmit={handleSubmit} className="dump-form">
-              {submitState.status === "error" && (
-                <ErrorCard
-                  title={t`Failed to post`}
-                  message={submitState.error}
-                />
-              )}
+            <FormProvider {...form}>
+              <form onSubmit={onSubmit} className="form">
+                <FormError title={t`Failed to post`} />
 
-              {mode === "url"
-                ? (
-                  <>
-                    <div className="form-group">
-                      <label htmlFor="dc-url">
-                        <Trans>URL</Trans>
-                      </label>
-                      <input
-                        id="dc-url"
-                        type="url"
-                        value={url}
-                        onChange={(e) => setUrl(e.target.value)}
-                        onBlur={(e) => setUrl(normalizeUrl(e.target.value))}
-                        onPaste={(e) => {
-                          const pastedFile = e.clipboardData.files[0];
-                          if (pastedFile) {
-                            e.preventDefault();
-                            setMode("file");
-                            setUrl("");
-                            selectFile(pastedFile);
-                            setSubmitState({ status: "idle" });
-                          }
-                        }}
-                        disabled={submitting}
-                        placeholder="https://..."
-                        required
-                        autoFocus
-                      />
-                    </div>
-                    {urlPreview.status === "loading" && (
-                      <p className="preview-loading">
-                        <Trans>Fetching preview…</Trans>
-                      </p>
-                    )}
-                    {urlPreview.status === "done" &&
-                      urlPreview.richContent && (
-                      <RichContentCard
-                        richContent={urlPreview.richContent}
-                      />
-                    )}
-                  </>
-                )
-                : (
-                  <>
-                    <FileDropZone
-                      file={file}
-                      onChange={selectFile}
-                      disabled={submitting}
-                    />
-                    {file && <LocalFilePreview file={file} />}
-                    {file && (
-                      <div className="form-group">
-                        <label htmlFor="dc-title">
-                          <Trans>Title</Trans>
+                {mode === "url"
+                  ? (
+                    <>
+                      <div className="form-field">
+                        <label className="form-label" htmlFor="dc-url">
+                          <Trans>URL</Trans>
                         </label>
-                        <div className="dump-create-title-row">
-                          <input
-                            id="dc-title"
-                            ref={titleInputRef}
-                            type="text"
-                            value={title}
-                            onChange={(e) => setTitle(e.target.value)}
-                            disabled={submitting || !titleEditing}
-                            maxLength={VALIDATION.DUMP_TITLE_MAX}
-                            required
-                          />
-                          {!titleEditing && (
-                            <button
-                              type="button"
-                              className="dump-create-title-edit-btn"
-                              onClick={() => {
-                                setTitleEditing(true);
-                                setTimeout(
-                                  () => titleInputRef.current?.focus(),
-                                  0,
-                                );
-                              }}
-                              disabled={submitting}
-                              aria-label={t`Edit title`}
-                            >
-                              ✎
-                            </button>
-                          )}
-                        </div>
+                        <input
+                          id="dc-url"
+                          type="url"
+                          {...register("url")}
+                          onBlur={(e) =>
+                            setValue("url", normalizeUrl(e.target.value))}
+                          onPaste={(e) => {
+                            const pastedFile = e.clipboardData.files[0];
+                            if (pastedFile) {
+                              e.preventDefault();
+                              setMode("file");
+                              setValue("url", "");
+                              selectFile(pastedFile);
+                              clearErrors("root");
+                            }
+                          }}
+                          disabled={submitting}
+                          placeholder="https://..."
+                          autoFocus
+                        />
                       </div>
-                    )}
-                  </>
-                )}
+                      {urlPreview.status === "loading" && (
+                        <p className="preview-loading">
+                          <Trans>Fetching preview…</Trans>
+                        </p>
+                      )}
+                      {urlPreview.status === "done" &&
+                        urlPreview.richContent && (
+                        <RichContentCard richContent={urlPreview.richContent} />
+                      )}
+                    </>
+                  )
+                  : (
+                    <>
+                      <Controller
+                        name="file"
+                        control={control}
+                        render={({ field }) => (
+                          <FileDropZone
+                            file={field.value}
+                            onChange={selectFile}
+                            disabled={submitting}
+                          />
+                        )}
+                      />
+                      {file && <LocalFilePreview file={file} />}
+                      {file && (
+                        <div className="form-field">
+                          <label className="form-label" htmlFor="dc-title">
+                            <Trans>Title</Trans>
+                          </label>
+                          <div className="dump-create-title-row">
+                            {(() => {
+                              const { ref, ...titleReg } = register("title");
+                              return (
+                                <input
+                                  id="dc-title"
+                                  type="text"
+                                  {...titleReg}
+                                  ref={(el) => {
+                                    ref(el);
+                                    titleInputRef.current = el;
+                                  }}
+                                  disabled={submitting || !titleEditing}
+                                  maxLength={VALIDATION.DUMP_TITLE_MAX}
+                                />
+                              );
+                            })()}
+                            {!titleEditing && (
+                              <button
+                                type="button"
+                                className="dump-create-title-edit-btn"
+                                onClick={() => {
+                                  setTitleEditing(true);
+                                  setTimeout(
+                                    () => titleInputRef.current?.focus(),
+                                    0,
+                                  );
+                                }}
+                                disabled={submitting}
+                                aria-label={t`Edit title`}
+                              >
+                                ✎
+                              </button>
+                            )}
+                          </div>
+                        </div>
+                      )}
+                    </>
+                  )}
 
-              <div className="form-group">
-                <label htmlFor="dc-comment">
-                  <Trans>Why?</Trans>
-                </label>
-                <TextEditor
-                  id="dc-comment"
-                  value={comment}
-                  onChange={setComment}
-                  disabled={submitting}
+                <RichTextField<CreateValues>
+                  name="comment"
+                  label={t`Why?`}
                   placeholder={t`What makes it worth it?`}
                   rows={3}
                   maxLength={VALIDATION.DUMP_COMMENT_MAX}
+                  rules={{ maxLength: VALIDATION.DUMP_COMMENT_MAX }}
+                  disabled={submitting}
                 />
-              </div>
 
-              <div className="visibility-toggle">
-                <button
-                  type="button"
-                  className={!isPrivate ? "active" : ""}
+                <VisibilityToggle<CreateValues>
+                  name="isPublic"
                   disabled={submitting}
-                  onClick={() => setIsPrivate(false)}
-                >
-                  <Trans>Public</Trans>
-                </button>
-                <button
-                  type="button"
-                  className={isPrivate ? "active" : ""}
-                  disabled={submitting}
-                  onClick={() => setIsPrivate(true)}
-                >
-                  <Trans>Private</Trans>
-                </button>
-              </div>
+                />
 
-              <div className="form-actions">
-                <div className="form-actions-right">
-                  <button
-                    type="button"
-                    className="form-cancel"
-                    onClick={onClose}
+                <FormActions onCancel={onClose}>
+                  <SubmitButton
+                    pendingLabel={mode === "url"
+                      ? <Trans>Fetching…</Trans>
+                      : <Trans>Uploading…</Trans>}
                   >
-                    <Trans>Cancel</Trans>
-                  </button>
-                  <button
-                    type="submit"
-                    className="btn-primary"
-                    disabled={submitting ||
-                      comment.length > VALIDATION.DUMP_COMMENT_MAX}
-                  >
-                    {submitting
-                      ? (mode === "url"
-                        ? <Trans>Fetching…</Trans>
-                        : <Trans>Uploading…</Trans>)
-                      : <Trans>Dump it</Trans>}
-                  </button>
-                </div>
-              </div>
-            </form>
+                    <Trans>Dump it</Trans>
+                  </SubmitButton>
+                </FormActions>
+              </form>
+            </FormProvider>
           </>
         )
         : (
@@ -512,11 +475,7 @@ export function DumpCreateModal(
 
             <div className="form-actions">
               <div className="form-actions-right">
-                <button
-                  type="button"
-                  className="btn-primary"
-                  onClick={onClose}
-                >
+                <button type="button" className="btn-primary" onClick={onClose}>
                   <Trans>Done</Trans>
                 </button>
               </div>

src/components/PlaylistCreateForm.tsx

@@ -1,13 +1,20 @@
-import { useState } from "react";
 import { t } from "@lingui/core/macro";
 import { Trans } from "@lingui/react/macro";
 import { API_URL, VALIDATION } from "../config/api.ts";
-import { CountedInput } from "./CountedInput.tsx";
 import type { CreatePlaylistRequest, Playlist, RawPlaylist } from "../model.ts";
-import { deserializePlaylist, parseAPIResponse } from "../model.ts";
+import { deserializePlaylist } from "../model.ts";
 import { useAuth } from "../hooks/useAuth.ts";
-import { ErrorCard } from "./ErrorCard.tsx";
-import { TextEditor } from "./TextEditor.tsx";
+import {
+  expectOk,
+  FormActions,
+  FormError,
+  FormProvider,
+  RichTextField,
+  SubmitButton,
+  TextField,
+  useApiForm,
+  VisibilityToggle,
+} from "./form/index.ts";
 
 interface PlaylistCreateFormProps {
   /** If provided, the new playlist will have this dump added to it. */
@@ -16,115 +23,71 @@ interface PlaylistCreateFormProps {
   onCancel: () => void;
 }
 
+interface Values {
+  title: string;
+  description: string;
+  isPublic: boolean;
+}
+
 export function PlaylistCreateForm(
   { dumpId, onCreated, onCancel }: PlaylistCreateFormProps,
 ) {
   const { authFetch } = useAuth();
-  const [title, setTitle] = useState("");
-  const [description, setDescription] = useState("");
-  const [isPublic, setIsPublic] = useState(true);
-  const [submitting, setSubmitting] = useState(false);
-  const [error, setError] = useState<string | null>(null);
+  const form = useApiForm<Values>({
+    defaultValues: { title: "", description: "", isPublic: true },
+  });
 
-  const handleSubmit = async (e: React.SubmitEvent) => {
-    e.preventDefault();
-    if (
-      !title.trim() || description.length > VALIDATION.PLAYLIST_DESCRIPTION_MAX
-    ) return;
-    setSubmitting(true);
-    setError(null);
-    try {
-      const res = await authFetch(`${API_URL}/api/playlists`, {
-        method: "POST",
-        headers: { "Content-Type": "application/json" },
-        body: JSON.stringify(
-          {
-            title: title.trim(),
-            description: description.trim() || undefined,
-            isPublic,
-          } satisfies CreatePlaylistRequest,
-        ),
-      });
-      const body = parseAPIResponse<RawPlaylist>(await res.json());
-      if (!body.success) {
-        setError(body.error.message);
-        return;
-      }
-      const playlist = deserializePlaylist(body.data as RawPlaylist);
-      if (dumpId) {
-        await authFetch(
-          `${API_URL}/api/playlists/${playlist.id}/dumps/${dumpId}`,
-          { method: "POST" },
-        );
-      }
-      onCreated(playlist);
-    } catch {
-      setError(t`Failed to create playlist`);
-    } finally {
-      setSubmitting(false);
+  const onSubmit = form.submit(async ({ title, description, isPublic }) => {
+    const playlist = deserializePlaylist(
+      await expectOk<RawPlaylist>(
+        await authFetch(`${API_URL}/api/playlists`, {
+          method: "POST",
+          headers: { "Content-Type": "application/json" },
+          body: JSON.stringify(
+            {
+              title: title.trim(),
+              description: description.trim() || undefined,
+              isPublic,
+            } satisfies CreatePlaylistRequest,
+          ),
+        }),
+      ),
+    );
+    if (dumpId) {
+      await authFetch(
+        `${API_URL}/api/playlists/${playlist.id}/dumps/${dumpId}`,
+        { method: "POST" },
+      );
     }
-  };
+    onCreated(playlist);
+  });
 
   return (
-    <form className="modal-new-playlist-form" onSubmit={handleSubmit}>
-      <CountedInput
-        type="text"
-        placeholder={t`Title`}
-        value={title}
-        onChange={(e) => setTitle(e.target.value)}
-        autoFocus
-        required
-        maxLength={VALIDATION.PLAYLIST_TITLE_MAX}
-      />
-      <TextEditor
-        placeholder={t`Description (optional)`}
-        value={description}
-        onChange={setDescription}
-        rows={3}
-        maxLength={VALIDATION.PLAYLIST_DESCRIPTION_MAX}
-      />
-      <div className="visibility-toggle">
-        <button
-          type="button"
-          className={isPublic ? "active" : ""}
-          onClick={() => setIsPublic(true)}
-        >
-          <Trans>Public</Trans>
-        </button>
-        <button
-          type="button"
-          className={!isPublic ? "active" : ""}
-          onClick={() => setIsPublic(false)}
-        >
-          <Trans>Private</Trans>
-        </button>
-      </div>
-      {error && (
-        <ErrorCard title={t`Failed to create playlist`} message={error} />
-      )}
-      <div className="form-actions">
-        <div className="form-actions-right">
-          <button
-            type="button"
-            className="form-cancel"
-            onClick={onCancel}
-          >
-            <Trans>Cancel</Trans>
-          </button>
-          <button
-            type="submit"
-            className="btn-primary"
-            disabled={submitting ||
-              description.length > VALIDATION.PLAYLIST_DESCRIPTION_MAX}
-          >
-            {submitting
-              ? <Trans>Creating…</Trans>
-              : dumpId
-              ? <Trans>Create & Add</Trans>
-              : <Trans>Create</Trans>}
-          </button>
-        </div>
-      </div>
-    </form>
+    <FormProvider {...form}>
+      <form className="form" onSubmit={onSubmit}>
+        <TextField<Values>
+          name="title"
+          placeholder={t`Title`}
+          autoFocus
+          rules={{ required: true }}
+          maxLength={VALIDATION.PLAYLIST_TITLE_MAX}
+          showCount
+        />
+        <RichTextField<Values>
+          name="description"
+          placeholder={t`Description (optional)`}
+          rows={3}
+          maxLength={VALIDATION.PLAYLIST_DESCRIPTION_MAX}
+          rules={{ maxLength: VALIDATION.PLAYLIST_DESCRIPTION_MAX }}
+        />
+        <VisibilityToggle<Values> name="isPublic" />
+        <FormError title={t`Failed to create playlist`} />
+        <FormActions onCancel={onCancel}>
+          <SubmitButton pendingLabel={<Trans>Creating…</Trans>}>
+            {dumpId ? <Trans>Create & Add</Trans> : <Trans>Create</Trans>}
+          </SubmitButton>
+        </FormActions>
+      </form>
+    </FormProvider>
   );
 }

src/components/form/FileField.tsx

@@ -0,0 +1,56 @@
+import {
+  Controller,
+  type FieldValues,
+  type Path,
+  type RegisterOptions,
+  useFormContext,
+} from "react-hook-form";
+
+import { FileDropZone } from "../FileDropZone.tsx";
+
+interface FileFieldProps<T extends FieldValues> {
+  name: Path<T>;
+  label?: string;
+  hint?: string;
+  showLimit?: boolean;
+  disabled?: boolean;
+  rules?: RegisterOptions<T, Path<T>>;
+}
+
+/** `Controller`-wrapped {@link FileDropZone} bound to react-hook-form. */
+export function FileField<T extends FieldValues>({
+  name,
+  label,
+  hint,
+  showLimit,
+  disabled,
+  rules,
+}: FileFieldProps<T>) {
+  const { control, formState: { errors } } = useFormContext<T>();
+  const error = errors[name];
+
+  return (
+    <div className="form-field">
+      <Controller
+        name={name}
+        control={control}
+        rules={rules}
+        render={({ field }) => (
+          <FileDropZone
+            file={(field.value as File | null) ?? null}
+            onChange={field.onChange}
+            label={label}
+            hint={hint}
+            showLimit={showLimit}
+            disabled={disabled}
+          />
+        )}
+      />
+      {error?.message && (
+        <span className="form-hint form-hint--error">
+          {String(error.message)}
+        </span>
+      )}
+    </div>
+  );
+}

src/components/form/FormActions.tsx

@@ -0,0 +1,39 @@
+import type { ReactNode } from "react";
+import { Trans } from "@lingui/react/macro";
+
+interface FormActionsProps {
+  children: ReactNode;
+  onCancel?: () => void;
+  cancelLabel?: ReactNode;
+  disabled?: boolean;
+}
+
+/**
+ * Right-aligned form action row: an optional Cancel button followed by the
+ * submit control(s). Standardizes the `.form-actions > .form-actions-right`
+ * markup duplicated across forms.
+ */
+export function FormActions({
+  children,
+  onCancel,
+  cancelLabel,
+  disabled,
+}: FormActionsProps) {
+  return (
+    <div className="form-actions">
+      <div className="form-actions-right">
+        {onCancel && (
+          <button
+            type="button"
+            className="form-cancel"
+            onClick={onCancel}
+            disabled={disabled}
+          >
+            {cancelLabel ?? <Trans>Cancel</Trans>}
+          </button>
+        )}
+        {children}
+      </div>
+    </div>
+  );
+}

src/components/form/FormError.tsx

@@ -0,0 +1,16 @@
+import { t } from "@lingui/core/macro";
+import { useFormState } from "react-hook-form";
+
+import { ErrorCard } from "../ErrorCard.tsx";
+
+/**
+ * Renders the form's root error (set by {@link useApiForm}'s `submit` on a
+ * thrown/failed request) through the shared {@link ErrorCard}. One consistent
+ * place for server/submit errors across every form.
+ */
+export function FormError({ title }: { title?: string }) {
+  const { errors } = useFormState();
+  const message = errors.root?.message;
+  if (!message) return null;
+  return <ErrorCard title={title ?? t`Something went wrong`} message={message} />;
+}

src/components/form/RichTextField.tsx

@@ -0,0 +1,81 @@
+import { useId } from "react";
+import {
+  Controller,
+  type FieldValues,
+  type Path,
+  type RegisterOptions,
+  useFormContext,
+} from "react-hook-form";
+
+import { TextEditor, type TextEditorHandle } from "../TextEditor.tsx";
+
+interface RichTextFieldProps<T extends FieldValues> {
+  name: Path<T>;
+  label?: string;
+  placeholder?: string;
+  rows?: number;
+  maxLength?: number;
+  autoResize?: boolean;
+  disabled?: boolean;
+  rules?: RegisterOptions<T, Path<T>>;
+  /** Forwarded to the underlying TextEditor so callers can focus it. */
+  editorRef?: React.Ref<TextEditorHandle>;
+  /** Ctrl/Cmd+Enter handler (e.g. submit the comment). */
+  onSubmit?: () => void;
+}
+
+/**
+ * Rich-text field: a `Controller`-wrapped {@link TextEditor} (mentions, emoji,
+ * image upload, char count) bound to react-hook-form via the surrounding
+ * `FormProvider`.
+ */
+export function RichTextField<T extends FieldValues>({
+  name,
+  label,
+  placeholder,
+  rows,
+  maxLength,
+  autoResize,
+  disabled,
+  rules,
+  editorRef,
+  onSubmit,
+}: RichTextFieldProps<T>) {
+  const id = useId();
+  const { control, formState: { errors } } = useFormContext<T>();
+  const error = errors[name];
+
+  return (
+    <div className="form-field">
+      {label && (
+        <label className="form-label" htmlFor={id}>
+          {label}
+        </label>
+      )}
+      <Controller
+        name={name}
+        control={control}
+        rules={rules}
+        render={({ field }) => (
+          <TextEditor
+            ref={editorRef}
+            id={id}
+            value={field.value ?? ""}
+            onChange={field.onChange}
+            placeholder={placeholder}
+            rows={rows}
+            maxLength={maxLength}
+            autoResize={autoResize}
+            disabled={disabled}
+            onSubmit={onSubmit}
+          />
+        )}
+      />
+      {error?.message && (
+        <span className="form-hint form-hint--error">
+          {String(error.message)}
+        </span>
+      )}
+    </div>
+  );
+}

src/components/form/SegmentedField.tsx

@@ -0,0 +1,82 @@
+import type { ReactNode } from "react";
+import { Trans } from "@lingui/react/macro";
+import {
+  Controller,
+  type FieldValues,
+  type Path,
+  useFormContext,
+} from "react-hook-form";
+
+interface SegmentedOption<V> {
+  value: V;
+  label: ReactNode;
+}
+
+interface SegmentedFieldProps<T extends FieldValues, V> {
+  name: Path<T>;
+  options: SegmentedOption<V>[];
+  label?: string;
+  disabled?: boolean;
+}
+
+/**
+ * Segmented control (the `.visibility-toggle` style) bound to react-hook-form.
+ * Generic over the field value, so it works for booleans, string unions, etc.
+ */
+export function SegmentedField<T extends FieldValues, V>({
+  name,
+  options,
+  label,
+  disabled,
+}: SegmentedFieldProps<T, V>) {
+  const { control } = useFormContext<T>();
+
+  return (
+    <div className="form-field">
+      {label && <span className="form-label">{label}</span>}
+      <Controller
+        name={name}
+        control={control}
+        render={({ field }) => (
+          <div className="visibility-toggle">
+            {options.map((opt) => (
+              <button
+                key={String(opt.value)}
+                type="button"
+                className={field.value === opt.value ? "active" : ""}
+                disabled={disabled}
+                onClick={() => field.onChange(opt.value)}
+              >
+                {opt.label}
+              </button>
+            ))}
+          </div>
+        )}
+      />
+    </div>
+  );
+}
+
+/**
+ * Public/Private toggle on a boolean field (default `isPublic`). Forms that
+ * persist `isPrivate` should still bind this to an `isPublic` field and invert
+ * at submit time.
+ */
+export function VisibilityToggle<T extends FieldValues>({
+  name,
+  disabled,
+}: {
+  name: Path<T>;
+  disabled?: boolean;
+}) {
+  return (
+    <SegmentedField<T, boolean>
+      name={name}
+      disabled={disabled}
+      options={[
+        { value: true, label: <Trans>Public</Trans> },
+        { value: false, label: <Trans>Private</Trans> },
+      ]}
+    />
+  );
+}

src/components/form/SubmitButton.tsx

@@ -0,0 +1,30 @@
+import type { ReactNode } from "react";
+import { useFormState } from "react-hook-form";
+
+interface SubmitButtonProps {
+  children: ReactNode;
+  /** Replaces the label while the form is submitting (e.g. "Saving…"). */
+  pendingLabel?: ReactNode;
+  disabled?: boolean;
+  className?: string;
+}
+
+/**
+ * Submit button that reflects react-hook-form's `isSubmitting` from the
+ * surrounding `FormProvider`: it disables itself while submitting and swaps in
+ * `pendingLabel`. Standardizes the hand-rolled "Save → Saving…" pattern.
+ */
+export function SubmitButton({
+  children,
+  pendingLabel,
+  disabled,
+  className = "btn-primary",
+}: SubmitButtonProps) {
+  const { isSubmitting } = useFormState();
+
+  return (
+    <button type="submit" className={className} disabled={isSubmitting || disabled}>
+      {isSubmitting && pendingLabel != null ? pendingLabel : children}
+    </button>
+  );
+}

src/components/form/TextField.tsx

@@ -0,0 +1,90 @@
+import { useId } from "react";
+import {
+  type FieldValues,
+  type Path,
+  type RegisterOptions,
+  useFormContext,
+  useWatch,
+} from "react-hook-form";
+
+import { charCountClass } from "../../utils/charCount.ts";
+
+interface TextFieldProps<T extends FieldValues> {
+  name: Path<T>;
+  label?: string;
+  type?: "text" | "email" | "password" | "url" | "search";
+  placeholder?: string;
+  autoComplete?: string;
+  autoFocus?: boolean;
+  disabled?: boolean;
+  rules?: RegisterOptions<T, Path<T>>;
+  /** Cap input length at `max` (native `maxLength`). */
+  maxLength?: number;
+  /** Show a live `n / maxLength` counter. Requires `maxLength`. */
+  showCount?: boolean;
+}
+
+/** Live `n / max` counter; isolated so only counted fields subscribe to value. */
+function CharCounter<T extends FieldValues>(
+  { name, max }: { name: Path<T>; max: number },
+) {
+  const value = useWatch({ name }) as string | undefined;
+  const len = value?.length ?? 0;
+  return (
+    <span className={`text-editor-count${charCountClass(len, max)}`}>
+      {len} / {max}
+    </span>
+  );
+}
+
+/**
+ * Native text input wired to react-hook-form via the surrounding `FormProvider`.
+ * Renders a label, the input (with an optional character counter), and a
+ * validation hint sourced from `formState.errors[name]`.
+ */
+export function TextField<T extends FieldValues>({
+  name,
+  label,
+  type = "text",
+  placeholder,
+  autoComplete,
+  autoFocus,
+  disabled,
+  rules,
+  maxLength,
+  showCount = false,
+}: TextFieldProps<T>) {
+  const id = useId();
+  const { register, formState: { errors } } = useFormContext<T>();
+  const error = errors[name];
+  const counted = showCount && maxLength != null;
+
+  return (
+    <div className="form-field">
+      {label && (
+        <label className="form-label" htmlFor={id}>
+          {label}
+        </label>
+      )}
+      <div className={counted ? "input-with-count" : undefined}>
+        <input
+          id={id}
+          type={type}
+          placeholder={placeholder}
+          autoComplete={autoComplete}
+          autoFocus={autoFocus}
+          disabled={disabled}
+          maxLength={maxLength}
+          aria-invalid={error ? true : undefined}
+          {...register(name, rules)}
+        />
+        {counted && <CharCounter<T> name={name} max={maxLength} />}
+      </div>
+      {error?.message && (
+        <span className="form-hint form-hint--error">
+          {String(error.message)}
+        </span>
+      )}
+    </div>
+  );
+}

src/components/form/index.ts

@@ -0,0 +1,9 @@
+export { expectOk, useApiForm } from "./useApiForm.ts";
+export { TextField } from "./TextField.tsx";
+export { RichTextField } from "./RichTextField.tsx";
+export { SegmentedField, VisibilityToggle } from "./SegmentedField.tsx";
+export { FileField } from "./FileField.tsx";
+export { SubmitButton } from "./SubmitButton.tsx";
+export { FormActions } from "./FormActions.tsx";
+export { FormError } from "./FormError.tsx";
+export { FormProvider } from "react-hook-form";

src/components/form/useApiForm.ts

@@ -0,0 +1,59 @@
+import { useCallback } from "react";
+import {
+  type FieldValues,
+  type SubmitHandler,
+  useForm,
+  type UseFormProps,
+  type UseFormReturn,
+} from "react-hook-form";
+
+import { friendlyFetchError } from "../../utils/apiError.ts";
+import { parseAPIResponse } from "../../model.ts";
+
+export interface UseApiFormReturn<T extends FieldValues> extends UseFormReturn<T> {
+  /**
+   * Wraps an async submit handler with the shared API-form lifecycle: clears the
+   * previous root error, runs the handler while RHF keeps `formState.isSubmitting`
+   * true, and on a thrown error surfaces a single root error via
+   * `friendlyFetchError`. Pair it with {@link expectOk} so API-level failures and
+   * network failures both become root errors through one code path. Returns the
+   * `onSubmit` handler to spread onto `<form onSubmit={...}>`.
+   */
+  submit: (
+    handler: SubmitHandler<T>,
+  ) => (e?: React.BaseSyntheticEvent) => Promise<void>;
+}
+
+export function useApiForm<T extends FieldValues>(
+  options?: UseFormProps<T>,
+): UseApiFormReturn<T> {
+  const form = useForm<T>(options);
+  const { handleSubmit, setError, clearErrors } = form;
+
+  const submit = useCallback(
+    (handler: SubmitHandler<T>) =>
+      handleSubmit(async (values, event) => {
+        clearErrors("root");
+        try {
+          await handler(values, event);
+        } catch (err) {
+          setError("root", { message: friendlyFetchError(err) });
+        }
+      }),
+    [handleSubmit, setError, clearErrors],
+  );
+
+  return { ...form, submit };
+}
+
+/**
+ * Reads a fetch `Response` through the standard API envelope and returns the
+ * payload, throwing the server's message on `success: false`. A thrown error
+ * here (or a network `TypeError` from the `fetch` itself) is caught by
+ * {@link useApiForm}'s `submit` and rendered as the form's root error.
+ */
+export async function expectOk<T>(res: Response): Promise<T> {
+  const body = parseAPIResponse<T>(await res.json());
+  if (!body.success) throw new Error(body.error.message);
+  return body.data;
+}

src/pages/DumpEdit.tsx

@@ -15,9 +15,20 @@ import { friendlyFetchError } from "../utils/apiError.ts";
 import { ConfirmModal } from "../components/ConfirmModal.tsx";
 import RichContentCard from "../components/RichContentCard.tsx";
 import FilePreview from "../components/FilePreview.tsx";
-import { TextEditor } from "../components/TextEditor.tsx";
 import { FileDropZone } from "../components/FileDropZone.tsx";
 import { ImagePicker } from "../components/ImagePicker.tsx";
+import {
+  expectOk,
+  FormError,
+  FormProvider,
+  RichTextField,
+  SubmitButton,
+  TextField,
+  useApiForm,
+  VisibilityToggle,
+} from "../components/form/index.ts";
+import { useAuth } from "../hooks/useAuth.ts";
+import { Controller } from "react-hook-form";
 
 type DumpEditState =
   | { status: "loading" }
@@ -30,11 +41,6 @@ export function DumpEdit() {
   const { authFetch, token } = useRequiredAuth();
 
   const [state, setState] = useState<DumpEditState>({ status: "loading" });
-  const [url, setUrl] = useState("");
-  const [title, setTitle] = useState("");
-  const [comment, setComment] = useState("");
-  const [isPrivate, setIsPrivate] = useState(false);
-  const [newFile, setNewFile] = useState<File | null>(null);
   const [confirmDelete, setConfirmDelete] = useState(false);
   const [refreshing, setRefreshing] = useState(false);
   const [thumbUploading, setThumbUploading] = useState(false);
@@ -52,12 +58,7 @@ export function DumpEdit() {
         const apiResponse = parseAPIResponse<RawDump>(await res.json());
 
         if (apiResponse.success) {
-          const dump: Dump = deserializeDump(apiResponse.data);
-          setUrl(dump.url ?? "");
-          setTitle(dump.title);
-          setComment(dump.comment ?? "");
-          setIsPrivate(dump.isPrivate);
-          setState({ status: "loaded", dump });
+          setState({ status: "loaded", dump: deserializeDump(apiResponse.data) });
         } else {
           setState({ status: "error", error: apiResponse.error.message });
         }
@@ -67,56 +68,6 @@ export function DumpEdit() {
     })();
   }, [selectedDump, token]);
 
-  const handleSave = async () => {
-    const trimmedTitle = title.trim();
-    if (
-      state.status !== "loaded" ||
-      comment.length > VALIDATION.DUMP_COMMENT_MAX ||
-      !trimmedTitle || trimmedTitle.length > VALIDATION.DUMP_TITLE_MAX
-    ) return;
-
-    let res: Response;
-
-    if (state.dump.kind === "file" && newFile) {
-      const formData = new FormData();
-      formData.append("file", newFile);
-      formData.append("title", trimmedTitle);
-      if (comment.trim()) formData.append("comment", comment.trim());
-      res = await authFetch(`${API_URL}/api/dumps/${state.dump.id}/file`, {
-        method: "PUT",
-        body: formData,
-      });
-    } else {
-      const body: UpdateDumpRequest = state.dump.kind === "url"
-        ? {
-          url: url.trim() || undefined,
-          title: trimmedTitle,
-          comment: comment.trim() || undefined,
-          isPrivate,
-        }
-        : {
-          title: trimmedTitle,
-          comment: comment.trim() || undefined,
-          isPrivate,
-        };
-      res = await authFetch(`${API_URL}/api/dumps/${state.dump.id}`, {
-        method: "PUT",
-        body: JSON.stringify(body),
-      });
-    }
-
-    const apiResponse = parseAPIResponse<RawDump>(await res.json());
-    if (!apiResponse.success) {
-      setState({ status: "error", error: apiResponse.error.message });
-      return;
-    }
-
-    const updatedDump: Dump = deserializeDump(apiResponse.data);
-    setState({ status: "loaded", dump: updatedDump });
-    setNewFile(null);
-    navigate(dumpUrl(updatedDump), { state: { dump: updatedDump } });
-  };
-
   const handleRefreshMetadata = async () => {
     if (state.status !== "loaded" || state.dump.kind !== "url") return;
 
@@ -128,8 +79,7 @@ export function DumpEdit() {
       );
       const apiResponse = await res.json();
       if (apiResponse.success) {
-        const updatedDump: Dump = deserializeDump(apiResponse.data);
-        setState({ status: "loaded", dump: updatedDump });
+        setState({ status: "loaded", dump: deserializeDump(apiResponse.data) });
       }
     } finally {
       setRefreshing(false);
@@ -274,138 +224,17 @@ export function DumpEdit() {
           )}
         </div>
 
-        <form
-          className="dump-form"
-          onSubmit={(e) => {
-            e.preventDefault();
-            handleSave();
-          }}
-        >
-          <div className="form-group">
-            <label>
-              <Trans>Thumbnail</Trans>
-            </label>
-            <div className="dump-edit-thumbnail-row">
-              <ImagePicker
-                src={currentThumbnailSrc}
-                size={64}
-                onChange={handleThumbnailChange}
-                uploading={thumbUploading}
-              />
-              {dump.thumbnailMime && (
-                <button
-                  type="button"
-                  className="btn-border"
-                  onClick={handleThumbnailReset}
-                  disabled={thumbUploading}
-                >
-                  <Trans>Reset to default</Trans>
-                </button>
-              )}
-            </div>
-          </div>
-
-          <div className="form-group">
-            <label htmlFor="title">
-              <Trans>Title</Trans>
-            </label>
-            <input
-              id="title"
-              type="text"
-              value={title}
-              onChange={(e) => setTitle(e.currentTarget.value)}
-              maxLength={VALIDATION.DUMP_TITLE_MAX}
-              required
-            />
-          </div>
-
-          {dump.kind === "url"
-            ? (
-              <div className="form-group">
-                <label htmlFor="url">
-                  <Trans>URL</Trans>
-                </label>
-                <input
-                  id="url"
-                  type="url"
-                  value={url}
-                  onChange={(e) => setUrl(e.currentTarget.value)}
-                  placeholder="https://..."
-                  required
-                />
-              </div>
-            )
-            : (
-              <div className="form-group">
-                <p className="dump-file-notice">
-                  <strong>{dump.fileName}</strong>
-                  {dump.fileSize != null && ` — ${formatBytes(dump.fileSize)}`}
-                </p>
-                <FileDropZone
-                  file={newFile}
-                  onChange={setNewFile}
-                  label={t`Replace file`}
-                  hint={t`Drop a replacement here`}
-                  showLimit={false}
-                />
-              </div>
-            )}
-
-          <div className="form-group">
-            <label htmlFor="comment">
-              <Trans>Why?</Trans>
-            </label>
-            <TextEditor
-              id="comment"
-              value={comment}
-              onChange={setComment}
-              placeholder={t`What makes it worth it?`}
-              rows={3}
-              maxLength={VALIDATION.DUMP_COMMENT_MAX}
-            />
-          </div>
-
-          <div className="visibility-toggle">
-            <button
-              type="button"
-              className={!isPrivate ? "active" : ""}
-              onClick={() => setIsPrivate(false)}
-            >
-              <Trans>Public</Trans>
-            </button>
-            <button
-              type="button"
-              className={isPrivate ? "active" : ""}
-              onClick={() => setIsPrivate(true)}
-            >
-              <Trans>Private</Trans>
-            </button>
-          </div>
-
-          <div className="form-actions">
-            <button
-              type="button"
-              onClick={() => setConfirmDelete(true)}
-              className="btn-danger"
-            >
-              <Trans>Delete dump</Trans>
-            </button>
-            <div className="form-actions-right">
-              <Link to={dumpUrl(dump)} className="form-cancel">
-                <Trans>Cancel</Trans>
-              </Link>
-              <button
-                type="submit"
-                className="btn-primary"
-                disabled={comment.length > VALIDATION.DUMP_COMMENT_MAX ||
-                  !title.trim() ||
-                  title.trim().length > VALIDATION.DUMP_TITLE_MAX}
-              >
-                <Trans>Save</Trans>
-              </button>
-            </div>
-          </div>
-        </form>
+        <DumpEditForm
+          key={dump.id}
+          dump={dump}
+          currentThumbnailSrc={currentThumbnailSrc}
+          thumbUploading={thumbUploading}
+          onThumbnailChange={handleThumbnailChange}
+          onThumbnailReset={handleThumbnailReset}
+          onRequestDelete={() => setConfirmDelete(true)}
+          onSaved={(updated) =>
+            navigate(dumpUrl(updated), { state: { dump: updated } })}
+        />
       </div>
       {confirmDelete && (
         <ConfirmModal
@@ -418,3 +247,180 @@ export function DumpEdit() {
     </PageShell>
   );
 }
+
+interface DumpEditFormProps {
+  dump: Dump;
+  currentThumbnailSrc: string | null;
+  thumbUploading: boolean;
+  onThumbnailChange: (file: File) => void;
+  onThumbnailReset: () => void;
+  onRequestDelete: () => void;
+  onSaved: (dump: Dump) => void;
+}
+
+interface EditValues {
+  title: string;
+  url: string;
+  comment: string;
+  isPublic: boolean;
+  newFile: File | null;
+}
+
+function DumpEditForm({
+  dump,
+  currentThumbnailSrc,
+  thumbUploading,
+  onThumbnailChange,
+  onThumbnailReset,
+  onRequestDelete,
+  onSaved,
+}: DumpEditFormProps) {
+  const { authFetch } = useAuth();
+  const form = useApiForm<EditValues>({
+    defaultValues: {
+      title: dump.title,
+      url: dump.url ?? "",
+      comment: dump.comment ?? "",
+      isPublic: !dump.isPrivate,
+      newFile: null,
+    },
+  });
+
+  const onSubmit = form.submit(
+    async ({ title, url, comment, isPublic, newFile }) => {
+      const trimmedTitle = title.trim();
+      const isPrivate = !isPublic;
+      let res: Response;
+
+      if (dump.kind === "file" && newFile) {
+        const formData = new FormData();
+        formData.append("file", newFile);
+        formData.append("title", trimmedTitle);
+        if (comment.trim()) formData.append("comment", comment.trim());
+        res = await authFetch(`${API_URL}/api/dumps/${dump.id}/file`, {
+          method: "PUT",
+          body: formData,
+        });
+      } else {
+        const body: UpdateDumpRequest = dump.kind === "url"
+          ? {
+            url: url.trim() || undefined,
+            title: trimmedTitle,
+            comment: comment.trim() || undefined,
+            isPrivate,
+          }
+          : {
+            title: trimmedTitle,
+            comment: comment.trim() || undefined,
+            isPrivate,
+          };
+        res = await authFetch(`${API_URL}/api/dumps/${dump.id}`, {
+          method: "PUT",
+          body: JSON.stringify(body),
+        });
+      }
+
+      onSaved(deserializeDump(await expectOk<RawDump>(res)));
+    },
+  );
+
+  return (
+    <FormProvider {...form}>
+      <form className="form" onSubmit={onSubmit}>
+        <FormError title={t`Could not save`} />
+
+        <div className="form-field">
+          <span className="form-label">
+            <Trans>Thumbnail</Trans>
+          </span>
+          <div className="dump-edit-thumbnail-row">
+            <ImagePicker
+              src={currentThumbnailSrc}
+              size={64}
+              onChange={onThumbnailChange}
+              uploading={thumbUploading}
+            />
+            {dump.thumbnailMime && (
+              <button
+                type="button"
+                className="btn-border"
+                onClick={onThumbnailReset}
+                disabled={thumbUploading}
+              >
+                <Trans>Reset to default</Trans>
+              </button>
+            )}
+          </div>
+        </div>
+
+        <TextField<EditValues>
+          name="title"
+          label={t`Title`}
+          maxLength={VALIDATION.DUMP_TITLE_MAX}
+          rules={{ required: true }}
+        />
+
+        {dump.kind === "url"
+          ? (
+            <TextField<EditValues>
+              name="url"
+              type="url"
+              label={t`URL`}
+              placeholder="https://..."
+              rules={{ required: true }}
+            />
+          )
+          : (
+            <div className="form-field">
+              <p className="dump-file-notice">
+                <strong>{dump.fileName}</strong>
+                {dump.fileSize != null && ` — ${formatBytes(dump.fileSize)}`}
+              </p>
+              <Controller
+                name="newFile"
+                control={form.control}
+                render={({ field }) => (
+                  <FileDropZone
+                    file={field.value}
+                    onChange={field.onChange}
+                    label={t`Replace file`}
+                    hint={t`Drop a replacement here`}
+                    showLimit={false}
+                  />
+                )}
+              />
+            </div>
+          )}
+
+        <RichTextField<EditValues>
+          name="comment"
+          label={t`Why?`}
+          placeholder={t`What makes it worth it?`}
+          rows={3}
+          maxLength={VALIDATION.DUMP_COMMENT_MAX}
+          rules={{ maxLength: VALIDATION.DUMP_COMMENT_MAX }}
+        />
+
+        <VisibilityToggle<EditValues> name="isPublic" />
+
+        <div className="form-actions">
+          <button
+            type="button"
+            onClick={onRequestDelete}
+            className="btn-danger"
+          >
+            <Trans>Delete dump</Trans>
+          </button>
+          <div className="form-actions-right">
+            <Link to={dumpUrl(dump)} className="form-cancel">
+              <Trans>Cancel</Trans>
+            </Link>
+            <SubmitButton>
+              <Trans>Save</Trans>
+            </SubmitButton>
+          </div>
+        </div>
+      </form>
+    </FormProvider>
+  );
+}

src/pages/PlaylistDetail.tsx

@@ -11,6 +11,7 @@ import { Trans } from "@lingui/react/macro";
 import { API_URL, VALIDATION } from "../config/api.ts";
 import { CountedInput } from "../components/CountedInput.tsx";
 import type {
+  Playlist,
   PlaylistWithDumps,
   RawDump,
   RawPlaylist,
@@ -22,7 +23,6 @@ import {
   deserializeDump,
   deserializePlaylist,
   deserializePlaylistWithDumps,
-  parseAPIResponse,
 } from "../model.ts";
 import { playlistUrl } from "../utils/urls.ts";
 import { useAuth } from "../hooks/useAuth.ts";
@@ -36,9 +36,16 @@ import { ImagePicker } from "../components/ImagePicker.tsx";
 import { Markdown } from "../components/Markdown.tsx";
 import { TextEditor } from "../components/TextEditor.tsx";
 import { FollowPlaylistButton } from "../components/FollowButton.tsx";
-import { ErrorCard } from "../components/ErrorCard.tsx";
 import { Tooltip } from "../components/Tooltip.tsx";
 import { friendlyFetchError } from "../utils/apiError.ts";
+import { Controller } from "react-hook-form";
+import {
+  expectOk,
+  FormError,
+  FormProvider,
+  SubmitButton,
+  useApiForm,
+} from "../components/form/index.ts";
 
 type LoadState =
   | { status: "loading" }
@@ -88,14 +95,7 @@ export function PlaylistDetail() {
   const [dragOverIndex, setDragOverIndex] = useState<number | null>(null);
 
   const [editOpen, setEditOpen] = useState(false);
-  const [editTitle, setEditTitle] = useState("");
-  const [editDescription, setEditDescription] = useState("");
-  const [editIsPublic, setEditIsPublic] = useState(true);
-  const [editSaving, setEditSaving] = useState(false);
-  const [editError, setEditError] = useState<string | null>(null);
   const [confirmDelete, setConfirmDelete] = useState(false);
-  const [imageFile, setImageFile] = useState<File | null>(null);
-  const [imagePreview, setImagePreview] = useState<string | null>(null);
 
   // Mirrors activeDumpIds for use in effects without adding it as a dep.
   // Updated on every render via useLayoutEffect so it's always current.
@@ -522,68 +522,11 @@ export function PlaylistDetail() {
       .catch(() => {});
   };
 
-  const openEdit = () => {
-    if (state.status !== "loaded") return;
-    setEditTitle(state.playlist.title);
-    setEditDescription(state.playlist.description ?? "");
-    setEditIsPublic(state.playlist.isPublic);
-    setImageFile(null);
-    setImagePreview(null);
-    setEditError(null);
-    setEditOpen(true);
-  };
+  const openEdit = () => setEditOpen(true);
 
-  const handleEditSave = async () => {
-    if (
-      !playlistId || state.status !== "loaded" ||
-      editDescription.length > VALIDATION.PLAYLIST_DESCRIPTION_MAX
-    ) return;
-    setEditSaving(true);
-    setEditError(null);
-    try {
-      const updateRes = await authFetch(
-        `${API_URL}/api/playlists/${playlistId}`,
-        {
-          method: "PUT",
-          headers: { "Content-Type": "application/json" },
-          body: JSON.stringify(
-            {
-              ...(editTitle !== state.playlist.title
-                ? { title: editTitle }
-                : {}),
-              ...(editDescription !== (state.playlist.description ?? "")
-                ? { description: editDescription || null }
-                : {}),
-              isPublic: editIsPublic,
-            } satisfies UpdatePlaylistRequest,
-          ),
-        },
-      );
-      const updateJson = parseAPIResponse<RawPlaylist>(await updateRes.json());
-      const updatedPlaylist = updateJson.success
-        ? deserializePlaylist(updateJson.data)
-        : null;
-
-      if (imageFile) {
-        const fd = new FormData();
-        fd.append("file", imageFile);
-        await authFetch(`${API_URL}/api/playlists/${playlistId}/image`, {
-          method: "POST",
-          body: fd,
-        });
-      }
-
-      setEditOpen(false);
-      if (updatedPlaylist) {
-        navigate(playlistUrl(updatedPlaylist), { replace: true });
-      } else {
-        fetchPlaylist();
-      }
-    } catch (err) {
-      setEditError(friendlyFetchError(err));
-    } finally {
-      setEditSaving(false);
-    }
+  const handleEditSaved = (updated: Playlist) => {
+    setEditOpen(false);
+    navigate(playlistUrl(updated), { replace: true });
   };
 
   const handleDelete = async () => {
@@ -636,125 +579,49 @@ export function PlaylistDetail() {
         <div className="playlist-detail-header-top">
           {editOpen
             ? (
-              <ImagePicker
-                src={imagePreview ??
-                  (playlist.imageMime
-                    ? `${API_URL}/api/playlists/${playlist.id}/image`
-                    : null)}
-                alt="Cover"
-                size={72}
-                onChange={(file) => {
-                  setImageFile(file);
-                  setImagePreview(URL.createObjectURL(file));
-                }}
+              <PlaylistEditForm
+                playlist={playlist}
+                onCancel={() => setEditOpen(false)}
+                onRequestDelete={() => setConfirmDelete(true)}
+                onSaved={handleEditSaved}
               />
             )
-            : playlist.imageMime && (
-              <img
-                src={`${API_URL}/api/playlists/${playlist.id}/image`}
-                alt=""
-                className="playlist-detail-img"
-              />
-            )}
-
-          <div className="playlist-detail-content">
-            {editOpen
-              ? (
-                <div className="playlist-detail-title-row">
-                  <CountedInput
-                    className="playlist-edit-input"
-                    value={editTitle}
-                    onChange={(e) => setEditTitle(e.target.value)}
-                    autoFocus
-                    maxLength={VALIDATION.PLAYLIST_TITLE_MAX}
+            : (
+              <>
+                {playlist.imageMime && (
+                  <img
+                    src={`${API_URL}/api/playlists/${playlist.id}/image`}
+                    alt=""
+                    className="playlist-detail-img"
                   />
-                  <button
-                    type="button"
-                    className="btn-primary"
-                    disabled={editSaving ||
-                      editDescription.length >
-                        VALIDATION.PLAYLIST_DESCRIPTION_MAX}
-                    onClick={handleEditSave}
-                  >
-                    {editSaving ? <Trans>Saving…</Trans> : <Trans>Save</Trans>}
-                  </button>
-                  <button
-                    type="button"
-                    className="form-cancel"
-                    onClick={() => setEditOpen(false)}
-                  >
-                    <Trans>Cancel</Trans>
-                  </button>
-                  <button
-                    type="button"
-                    className="btn-danger"
-                    onClick={() => setConfirmDelete(true)}
-                  >
-                    <Trans>Delete</Trans>
-                  </button>
-                </div>
-              )
-              : (
-                <div className="playlist-detail-title-row">
-                  <h1 className="playlist-detail-title">{playlist.title}</h1>
-                  {!isOwner && (
-                    <FollowPlaylistButton
-                      targetPlaylistId={playlist.id}
-                      isPublic={playlist.isPublic}
-                    />
-                  )}
-                  {isOwner && (
-                    <button
-                      type="button"
-                      className="playlist-edit-btn"
-                      onClick={openEdit}
-                    >
-                      <Trans>Edit</Trans>
-                    </button>
-                  )}
-                </div>
-              )}
-
-            {editOpen
-              ? (
-                <TextEditor
-                  className="playlist-edit-textarea"
-                  value={editDescription}
-                  onChange={setEditDescription}
-                  placeholder={t`Description (optional)`}
-                  autoResize
-                  rows={1}
-                  maxLength={VALIDATION.PLAYLIST_DESCRIPTION_MAX}
-                />
-              )
-              : playlist.description && (
-                <Markdown className="playlist-detail-description">
-                  {playlist.description}
-                </Markdown>
-              )}
-
-            <div className="playlist-detail-meta">
-              {editOpen
-                ? (
-                  <div className="visibility-toggle playlist-edit-toggle">
-                    <button
-                      type="button"
-                      className={editIsPublic ? "active" : ""}
-                      onClick={() => setEditIsPublic(true)}
-                    >
-                      <Trans>Public</Trans>
-                    </button>
-                    <button
-                      type="button"
-                      className={!editIsPublic ? "active" : ""}
-                      onClick={() => setEditIsPublic(false)}
-                    >
-                      <Trans>Private</Trans>
-                    </button>
+                )}
+                <div className="playlist-detail-content">
+                  <div className="playlist-detail-title-row">
+                    <h1 className="playlist-detail-title">{playlist.title}</h1>
+                    {!isOwner && (
+                      <FollowPlaylistButton
+                        targetPlaylistId={playlist.id}
+                        isPublic={playlist.isPublic}
+                      />
+                    )}
+                    {isOwner && (
+                      <button
+                        type="button"
+                        className="playlist-edit-btn"
+                        onClick={openEdit}
+                      >
+                        <Trans>Edit</Trans>
+                      </button>
+                    )}
                   </div>
-                )
-                : (
-                  <>
+
+                  {playlist.description && (
+                    <Markdown className="playlist-detail-description">
+                      {playlist.description}
+                    </Markdown>
+                  )}
+
+                  <div className="playlist-detail-meta">
                     <span
                       className={`playlist-badge${
                         playlist.isPublic ? "" : " playlist-badge--private"
@@ -788,13 +655,10 @@ export function PlaylistDetail() {
                         </span>
                       </Tooltip>
                     )}
-                  </>
-                )}
-            </div>
-            {editError && (
-              <ErrorCard title={t`Failed to save`} message={editError} />
+                  </div>
+                </div>
+              </>
             )}
-          </div>
         </div>
       </div>
 
@@ -887,3 +751,173 @@ export function PlaylistDetail() {
     </PageShell>
   );
 }
+
+interface PlaylistEditFormProps {
+  playlist: PlaylistWithDumps;
+  onCancel: () => void;
+  onRequestDelete: () => void;
+  onSaved: (playlist: Playlist) => void;
+}
+
+interface EditValues {
+  title: string;
+  description: string;
+  isPublic: boolean;
+  image: File | null;
+}
+
+function PlaylistEditForm(
+  { playlist, onCancel, onRequestDelete, onSaved }: PlaylistEditFormProps,
+) {
+  const { authFetch } = useAuth();
+  const [imagePreview, setImagePreview] = useState<string | null>(null);
+  const form = useApiForm<EditValues>({
+    defaultValues: {
+      title: playlist.title,
+      description: playlist.description ?? "",
+      isPublic: playlist.isPublic,
+      image: null,
+    },
+  });
+  const description = form.watch("description");
+
+  const onSubmit = form.submit(
+    async ({ title, description, isPublic, image }) => {
+      const updated = deserializePlaylist(
+        await expectOk<RawPlaylist>(
+          await authFetch(`${API_URL}/api/playlists/${playlist.id}`, {
+            method: "PUT",
+            headers: { "Content-Type": "application/json" },
+            body: JSON.stringify(
+              {
+                ...(title !== playlist.title ? { title } : {}),
+                ...(description !== (playlist.description ?? "")
+                  ? { description: description || null }
+                  : {}),
+                isPublic,
+              } satisfies UpdatePlaylistRequest,
+            ),
+          }),
+        ),
+      );
+
+      if (image) {
+        const fd = new FormData();
+        fd.append("file", image);
+        await authFetch(`${API_URL}/api/playlists/${playlist.id}/image`, {
+          method: "POST",
+          body: fd,
+        });
+      }
+
+      onSaved(updated);
+    },
+  );
+
+  return (
+    <FormProvider {...form}>
+      {/* `display: contents` keeps the image-beside-content flex layout while
+          still giving us a real <form> for submit + Enter handling. */}
+      <form style={{ display: "contents" }} onSubmit={onSubmit}>
+        <Controller
+          name="image"
+          control={form.control}
+          render={({ field }) => (
+            <ImagePicker
+              src={imagePreview ??
+                (playlist.imageMime
+                  ? `${API_URL}/api/playlists/${playlist.id}/image`
+                  : null)}
+              alt="Cover"
+              size={72}
+              onChange={(file) => {
+                field.onChange(file);
+                setImagePreview(URL.createObjectURL(file));
+              }}
+            />
+          )}
+        />
+
+        <div className="playlist-detail-content playlist-edit-content">
+          <Controller
+            name="title"
+            control={form.control}
+            render={({ field }) => (
+              <CountedInput
+                className="playlist-edit-input"
+                value={field.value}
+                onChange={field.onChange}
+                autoFocus
+                placeholder={t`Playlist title`}
+                maxLength={VALIDATION.PLAYLIST_TITLE_MAX}
+              />
+            )}
+          />
+
+          <Controller
+            name="description"
+            control={form.control}
+            render={({ field }) => (
+              <TextEditor
+                className="playlist-edit-textarea"
+                value={field.value}
+                onChange={field.onChange}
+                placeholder={t`Description (optional)`}
+                autoResize
+                rows={2}
+                maxLength={VALIDATION.PLAYLIST_DESCRIPTION_MAX}
+              />
+            )}
+          />
+
+          <Controller
+            name="isPublic"
+            control={form.control}
+            render={({ field }) => (
+              <div className="visibility-toggle playlist-edit-toggle">
+                <button
+                  type="button"
+                  className={field.value ? "active" : ""}
+                  onClick={() => field.onChange(true)}
+                >
+                  <Trans>Public</Trans>
+                </button>
+                <button
+                  type="button"
+                  className={!field.value ? "active" : ""}
+                  onClick={() => field.onChange(false)}
+                >
+                  <Trans>Private</Trans>
+                </button>
+              </div>
+            )}
+          />
+
+          <FormError title={t`Failed to save`} />
+
+          <div className="form-actions">
+            <button
+              type="button"
+              className="btn-danger"
+              onClick={onRequestDelete}
+            >
+              <Trans>Delete</Trans>
+            </button>
+            <div className="form-actions-right">
+              <button type="button" className="form-cancel" onClick={onCancel}>
+                <Trans>Cancel</Trans>
+              </button>
+              <SubmitButton
+                pendingLabel={<Trans>Saving…</Trans>}
+                disabled={description.length >
+                  VALIDATION.PLAYLIST_DESCRIPTION_MAX}
+              >
+                <Trans>Save</Trans>
+              </SubmitButton>
+            </div>
+          </div>
+        </div>
+      </form>
+    </FormProvider>
+  );
+}

src/pages/ResetPassword.tsx

@@ -4,27 +4,42 @@ import { t } from "@lingui/core/macro";
 import { Trans } from "@lingui/react/macro";
 
 import { API_URL, VALIDATION } from "../config/api.ts";
-import { ErrorCard } from "../components/ErrorCard.tsx";
 import { PageShell } from "../components/PageShell.tsx";
+import {
+  expectOk,
+  FormError,
+  FormProvider,
+  SubmitButton,
+  TextField,
+  useApiForm,
+} from "../components/form/index.ts";
 
-type State =
-  | { status: "idle" }
-  | { status: "submitting" }
-  | { status: "done" }
-  | { status: "error"; error: string };
+interface Values {
+  newPassword: string;
+  confirm: string;
+}
 
 export function ResetPassword() {
   const [params] = useSearchParams();
   const navigate = useNavigate();
   const token = params.get("token") ?? "";
+  const [done, setDone] = useState(false);
 
-  const [newPassword, setNewPassword] = useState("");
-  const [confirm, setConfirm] = useState("");
-  const [state, setState] = useState<State>({ status: "idle" });
+  const form = useApiForm<Values>({
+    mode: "onChange",
+    defaultValues: { newPassword: "", confirm: "" },
+  });
 
-  const mismatch = confirm.length > 0 && newPassword !== confirm;
-  const tooShort = newPassword.length > 0 &&
-    newPassword.length < VALIDATION.PASSWORD_MIN;
+  const onSubmit = form.submit(async ({ newPassword }) => {
+    await expectOk(
+      await fetch(`${API_URL}/api/users/reset-password`, {
+        method: "POST",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify({ token, newPassword }),
+      }),
+    );
+    setDone(true);
+  });
 
   if (!token) {
     return (
@@ -48,7 +63,7 @@ export function ResetPassword() {
     );
   }
 
-  if (state.status === "done") {
+  if (done) {
     return (
       <PageShell centered>
         <div className="auth-card">
@@ -70,31 +85,6 @@ export function ResetPassword() {
     );
   }
 
-  const handleSubmit = async (e: React.SubmitEvent) => {
-    e.preventDefault();
-    if (mismatch || tooShort || !newPassword) return;
-
-    setState({ status: "submitting" });
-    try {
-      const res = await fetch(`${API_URL}/api/users/reset-password`, {
-        method: "POST",
-        headers: { "Content-Type": "application/json" },
-        body: JSON.stringify({ token, newPassword }),
-      });
-      const body = await res.json();
-      if (body.success) {
-        setState({ status: "done" });
-      } else {
-        setState({
-          status: "error",
-          error: body.error?.message ?? t`Unknown error`,
-        });
-      }
-    } catch {
-      setState({ status: "error", error: t`Could not connect to server` });
-    }
-  };
-
   return (
     <PageShell centered>
       <div className="auth-card">
@@ -102,57 +92,40 @@ export function ResetPassword() {
           <Trans>Set new password</Trans>
         </h1>
 
-        {state.status === "error" && (
-          <ErrorCard title={t`Reset failed`} message={state.error} />
-        )}
-
-        <form onSubmit={handleSubmit} className="auth-form">
-          <div className="form-group">
-            <input
+        <FormProvider {...form}>
+          <form onSubmit={onSubmit} className="form">
+            <FormError title={t`Reset failed`} />
+            <TextField<Values>
+              name="newPassword"
               type="password"
               placeholder={t`New password`}
-              value={newPassword}
-              onChange={(e) => setNewPassword(e.target.value)}
               autoComplete="new-password"
-              minLength={VALIDATION.PASSWORD_MIN}
-              maxLength={VALIDATION.PASSWORD_MAX}
-              required
               autoFocus
-              disabled={state.status === "submitting"}
+              maxLength={VALIDATION.PASSWORD_MAX}
+              rules={{
+                required: true,
+                minLength: {
+                  value: VALIDATION.PASSWORD_MIN,
+                  message: t`At least ${VALIDATION.PASSWORD_MIN} characters`,
+                },
+              }}
             />
-            {tooShort && (
-              <span className="auth-field-hint auth-field-hint--error">
-                <Trans>At least {VALIDATION.PASSWORD_MIN} characters</Trans>
-              </span>
-            )}
-          </div>
-          <div className="form-group">
-            <input
+            <TextField<Values>
+              name="confirm"
               type="password"
               placeholder={t`Confirm new password`}
-              value={confirm}
-              onChange={(e) => setConfirm(e.target.value)}
               autoComplete="new-password"
-              required
-              disabled={state.status === "submitting"}
+              rules={{
+                required: true,
+                validate: (value, values) =>
+                  value === values.newPassword || t`Passwords do not match`,
+              }}
             />
-            {mismatch && (
-              <span className="auth-field-hint auth-field-hint--error">
-                <Trans>Passwords do not match</Trans>
-              </span>
-            )}
-          </div>
-          <button
-            type="submit"
-            className="btn-primary"
-            disabled={state.status === "submitting" || mismatch || tooShort ||
-              !newPassword || !confirm}
-          >
-            {state.status === "submitting"
-              ? <Trans>Saving…</Trans>
-              : <Trans>Set new password</Trans>}
-          </button>
-        </form>
+            <SubmitButton pendingLabel={<Trans>Saving…</Trans>}>
+              <Trans>Set new password</Trans>
+            </SubmitButton>
+          </form>
+        </FormProvider>
 
         <p className="auth-card-footer">
           <Link to="/login">

src/pages/UserLogin.tsx

@@ -1,5 +1,4 @@
 import { useState } from "react";
-import type { SubmitEvent } from "react";
 import { useNavigate } from "react-router";
 import { t } from "@lingui/core/macro";
 import { Trans } from "@lingui/react/macro";
@@ -8,77 +7,48 @@ import { API_URL } from "../config/api.ts";
 import {
   deserializeAuthResponse,
   type LoginRequest,
-  parseAPIResponse,
   type RawAuthResponse,
 } from "../model.ts";
 import { useAuth } from "../hooks/useAuth.ts";
 import { PageShell } from "../components/PageShell.tsx";
-import { ErrorCard } from "../components/ErrorCard.tsx";
-import { friendlyFetchError } from "../utils/apiError.ts";
+import {
+  expectOk,
+  FormError,
+  FormProvider,
+  SubmitButton,
+  TextField,
+  useApiForm,
+} from "../components/form/index.ts";
 
-type LoginState =
-  | { status: "idle" }
-  | { status: "submitting" }
-  | { status: "error"; error: string };
+interface LoginValues {
+  username: string;
+  password: string;
+}
 
-type ResetState =
-  | { status: "idle" }
-  | { status: "submitting" }
-  | { status: "sent" }
-  | { status: "error"; error: string };
+interface ResetValues {
+  email: string;
+}
 
 export function UserLogin() {
   const navigate = useNavigate();
   const { login } = useAuth();
-
-  const [loginState, setLoginState] = useState<LoginState>({ status: "idle" });
   const [showReset, setShowReset] = useState(false);
-  const [resetEmail, setResetEmail] = useState("");
-  const [resetState, setResetState] = useState<ResetState>({ status: "idle" });
 
-  const handleSubmit = async (e: SubmitEvent<HTMLFormElement>) => {
-    e.preventDefault();
-    setLoginState({ status: "submitting" });
+  const form = useApiForm<LoginValues>({
+    defaultValues: { username: "", password: "" },
+  });
 
-    const formData = new FormData(e.currentTarget);
-    const username = formData.get("username") as string;
-    const password = formData.get("password") as string;
-
-    try {
-      const res = await fetch(`${API_URL}/api/users/login`, {
+  const onSubmit = form.submit(async ({ username, password }) => {
+    const data = await expectOk<RawAuthResponse>(
+      await fetch(`${API_URL}/api/users/login`, {
         method: "POST",
         headers: { "Content-Type": "application/json" },
         body: JSON.stringify({ username, password } satisfies LoginRequest),
-      });
-
-      const apiResponse = parseAPIResponse<RawAuthResponse>(await res.json());
-
-      if (apiResponse.success) {
-        login(deserializeAuthResponse(apiResponse.data));
-        navigate("/");
-      } else {
-        setLoginState({ status: "error", error: apiResponse.error.message });
-      }
-    } catch (err) {
-      setLoginState({ status: "error", error: friendlyFetchError(err) });
-    }
-  };
-
-  const handleResetRequest = async (e: React.SubmitEvent) => {
-    e.preventDefault();
-    if (!resetEmail.trim()) return;
-    setResetState({ status: "submitting" });
-    try {
-      await fetch(`${API_URL}/api/users/request-password-reset`, {
-        method: "POST",
-        headers: { "Content-Type": "application/json" },
-        body: JSON.stringify({ email: resetEmail.trim() }),
-      });
-      setResetState({ status: "sent" });
-    } catch {
-      setResetState({ status: "error", error: t`Could not connect to server` });
-    }
-  };
+      }),
+    );
+    login(deserializeAuthResponse(data));
+    navigate("/");
+  });
 
   return (
     <PageShell centered>
@@ -87,98 +57,38 @@ export function UserLogin() {
           <Trans>Log in</Trans>
         </h1>
 
-        {loginState.status === "error" && (
-          <ErrorCard title={t`Login failed`} message={loginState.error} />
-        )}
-
-        <form onSubmit={handleSubmit} className="auth-form">
-          <input
-            name="username"
-            type="text"
-            placeholder={t`Username`}
-            required
-            disabled={loginState.status === "submitting"}
-            autoFocus
-          />
-          <input
-            name="password"
-            type="password"
-            placeholder={t`Password`}
-            required
-            disabled={loginState.status === "submitting"}
-          />
-          <button
-            type="submit"
-            className="btn-primary"
-            disabled={loginState.status === "submitting"}
-          >
-            {loginState.status === "submitting"
-              ? <Trans>Logging in…</Trans>
-              : <Trans>Log in</Trans>}
-          </button>
-        </form>
+        <FormProvider {...form}>
+          <form onSubmit={onSubmit} className="form">
+            <FormError title={t`Login failed`} />
+            <TextField<LoginValues>
+              name="username"
+              placeholder={t`Username`}
+              autoFocus
+              rules={{ required: true }}
+            />
+            <TextField<LoginValues>
+              name="password"
+              type="password"
+              placeholder={t`Password`}
+              rules={{ required: true }}
+            />
+            <SubmitButton pendingLabel={<Trans>Logging in…</Trans>}>
+              <Trans>Log in</Trans>
+            </SubmitButton>
+          </form>
+        </FormProvider>
 
         <p className="auth-card-footer">
           <button
             type="button"
             className="auth-link-btn"
-            onClick={() => {
-              setShowReset((v) => !v);
-              setResetState({ status: "idle" });
-              setResetEmail("");
-            }}
+            onClick={() => setShowReset((v) => !v)}
           >
             <Trans>Forgot password?</Trans>
           </button>
         </p>
 
-        {showReset && (
-          <div className="auth-reset-panel">
-            {resetState.status === "sent"
-              ? (
-                <p className="auth-reset-sent">
-                  <Trans>
-                    If that address is registered you'll receive a reset link
-                    shortly.
-                  </Trans>
-                </p>
-              )
-              : (
-                <>
-                  {resetState.status === "error" && (
-                    <ErrorCard
-                      title={t`Request failed`}
-                      message={resetState.error}
-                    />
-                  )}
-                  <form
-                    onSubmit={handleResetRequest}
-                    className="auth-form auth-reset-form"
-                  >
-                    <input
-                      type="email"
-                      placeholder={t`Your email address`}
-                      value={resetEmail}
-                      onChange={(e) => setResetEmail(e.target.value)}
-                      required
-                      autoFocus
-                      disabled={resetState.status === "submitting"}
-                    />
-                    <button
-                      type="submit"
-                      className="btn-primary"
-                      disabled={resetState.status === "submitting" ||
-                        !resetEmail.trim()}
-                    >
-                      {resetState.status === "submitting"
-                        ? <Trans>Sending…</Trans>
-                        : <Trans>Send reset link</Trans>}
-                    </button>
-                  </form>
-                </>
-              )}
-          </div>
-        )}
+        {showReset && <ResetRequestPanel />}
 
         <p className="auth-card-footer">
           <Trans>This is a mirage.</Trans>
@@ -187,3 +97,49 @@ export function UserLogin() {
     </PageShell>
   );
 }
+
+function ResetRequestPanel() {
+  const [sent, setSent] = useState(false);
+  const form = useApiForm<ResetValues>({ defaultValues: { email: "" } });
+
+  const onSubmit = form.submit(async ({ email }) => {
+    await fetch(`${API_URL}/api/users/request-password-reset`, {
+      method: "POST",
+      headers: { "Content-Type": "application/json" },
+      body: JSON.stringify({ email: email.trim() }),
+    });
+    setSent(true);
+  });
+
+  if (sent) {
+    return (
+      <div className="auth-reset-panel">
+        <p className="auth-reset-sent">
+          <Trans>
+            If that address is registered you'll receive a reset link shortly.
+          </Trans>
+        </p>
+      </div>
+    );
+  }
+
+  return (
+    <div className="auth-reset-panel">
+      <FormProvider {...form}>
+        <form onSubmit={onSubmit} className="form auth-reset-form">
+          <FormError title={t`Request failed`} />
+          <TextField<ResetValues>
+            name="email"
+            type="email"
+            placeholder={t`Your email address`}
+            autoFocus
+            rules={{ required: true }}
+          />
+          <SubmitButton pendingLabel={<Trans>Sending…</Trans>}>
+            <Trans>Send reset link</Trans>
+          </SubmitButton>
+        </form>
+      </FormProvider>
+    </div>
+  );
+}

src/pages/UserPublicProfile.tsx

@@ -55,6 +55,14 @@ import { Markdown } from "../components/Markdown.tsx";
 import { ChangePasswordModal } from "../components/ChangePasswordModal.tsx";
 import { TabBar } from "../components/TabBar.tsx";
 import { useTabParam } from "../hooks/useTabParam.ts";
+import { Controller } from "react-hook-form";
+import {
+  expectOk,
+  FormError,
+  FormProvider,
+  SubmitButton,
+  useApiForm,
+} from "../components/form/index.ts";
 
 function InviteButton() {
   const { authFetch } = useAuth();
@@ -292,14 +300,7 @@ export function UserPublicProfile() {
   const fileInputRef = useRef<HTMLInputElement>(null);
 
   const [descEditing, setDescEditing] = useState(false);
-  const [descDraft, setDescDraft] = useState("");
-  const [descSaving, setDescSaving] = useState(false);
-  const [descError, setDescError] = useState<string | null>(null);
-
   const [emailEditing, setEmailEditing] = useState(false);
-  const [emailDraft, setEmailDraft] = useState("");
-  const [emailSaving, setEmailSaving] = useState(false);
-  const [emailError, setEmailError] = useState<string | null>(null);
   const prevMyVotesRef = useRef<Set<string> | null>(null);
 
   const [changePasswordOpen, setChangePasswordOpen] = useState(false);
@@ -674,72 +675,22 @@ export function UserPublicProfile() {
     }
   };
 
-  const handleEmailSave = async () => {
-    if (state.status !== "loaded") return;
-    setEmailSaving(true);
-    setEmailError(null);
-    try {
-      const res = await authFetch(`${API_URL}/api/users/me`, {
-        method: "PATCH",
-        headers: { "Content-Type": "application/json" },
-        body: JSON.stringify(
-          { email: emailDraft.trim() } satisfies UpdateUserRequest,
-        ),
-      });
-      const body = parseAPIResponse<RawPublicUser>(await res.json());
-      if (!body.success) {
-        setEmailError(body.error.message);
-        return;
-      }
-      const storedRaw = localStorage.getItem("authResponse");
-      if (storedRaw) {
-        const prev = deserializeAuthResponse(JSON.parse(storedRaw));
-        login({ ...prev, user: { ...prev.user, email: emailDraft.trim() } });
-      }
-      setEmailEditing(false);
-    } catch {
-      setEmailError(t`Failed to save`);
-    } finally {
-      setEmailSaving(false);
+  const handleEmailSaved = (email: string) => {
+    const storedRaw = localStorage.getItem("authResponse");
+    if (storedRaw) {
+      const prev = deserializeAuthResponse(JSON.parse(storedRaw));
+      login({ ...prev, user: { ...prev.user, email } });
     }
+    setEmailEditing(false);
   };
 
-  const handleDescSave = async () => {
-    if (
-      state.status !== "loaded" ||
-      descDraft.length > VALIDATION.USER_DESCRIPTION_MAX
-    ) return;
-    setDescSaving(true);
-    setDescError(null);
-    try {
-      const res = await authFetch(`${API_URL}/api/users/me`, {
-        method: "PATCH",
-        headers: { "Content-Type": "application/json" },
-        body: JSON.stringify(
-          {
-            description: descDraft.trim() || undefined,
-          } satisfies UpdateUserRequest,
-        ),
-      });
-      const body = parseAPIResponse<RawPublicUser>(await res.json());
-      if (!body.success) {
-        setDescError(body.error.message);
-        return;
-      }
-      setState((s) =>
-        s.status === "loaded"
-          ? {
-            ...s,
-            user: { ...s.user, description: descDraft.trim() || undefined },
-          }
-          : s
-      );
-      setDescEditing(false);
-    } catch {
-      setDescError(t`Failed to save`);
-    } finally {
-      setDescSaving(false);
-    }
+  const handleDescSaved = (description: string | undefined) => {
+    setState((s) =>
+      s.status === "loaded"
+        ? { ...s, user: { ...s.user, description } }
+        : s
+    );
+    setDescEditing(false);
   };
 
   if (state.status === "loading") {
@@ -826,59 +777,16 @@ export function UserPublicProfile() {
             {isOwnProfile && (
               emailEditing
                 ? (
-                  <form
-                    className="profile-email-editor"
-                    onSubmit={(e) => {
-                      e.preventDefault();
-                      handleEmailSave();
-                    }}
-                  >
-                    <input
-                      type="email"
-                      className="profile-email-input"
-                      value={emailDraft}
-                      onChange={(e) => setEmailDraft(e.currentTarget.value)}
-                      onKeyDown={(e) => {
-                        if (e.key === "Escape") setEmailEditing(false);
-                      }}
-                      disabled={emailSaving}
-                      autoFocus
-                    />
-                    <div className="profile-email-actions">
-                      <button
-                        type="submit"
-                        className="profile-email-btn profile-email-btn--save"
-                        disabled={emailSaving || !emailDraft.trim()}
-                      >
-                        {emailSaving
-                          ? <Trans>Saving…</Trans>
-                          : <Trans>Save</Trans>}
-                      </button>
-                      <button
-                        type="button"
-                        className="profile-email-btn profile-email-btn--cancel"
-                        onClick={() => setEmailEditing(false)}
-                        disabled={emailSaving}
-                      >
-                        <Trans>Cancel</Trans>
-                      </button>
-                    </div>
-                    {emailError && (
-                      <ErrorCard
-                        title={t`Failed to save`}
-                        message={emailError}
-                      />
-                    )}
-                  </form>
+                  <EmailEditor
+                    initialEmail={me?.email ?? ""}
+                    onCancel={() => setEmailEditing(false)}
+                    onSaved={handleEmailSaved}
+                  />
                 )
                 : (
                   <p
                     className="profile-email-display"
-                    onClick={() => {
-                      setEmailDraft(me?.email ?? "");
-                      setEmailError(null);
-                      setEmailEditing(true);
-                    }}
+                    onClick={() => setEmailEditing(true)}
                     title="Edit email"
                   >
                     {me?.email ?? t`Add email…`}
@@ -916,39 +824,11 @@ export function UserPublicProfile() {
         <div className="profile-description">
           {descEditing
             ? (
-              <div className="profile-description-editor">
-                <TextEditor
-                  className="comment-reply-textarea"
-                  value={descDraft}
-                  onChange={setDescDraft}
-                  onSubmit={handleDescSave}
-                  placeholder={t`Who am I?`}
-                  autoResize
-                  maxLength={VALIDATION.USER_DESCRIPTION_MAX}
-                />
-                <div className="profile-description-actions">
-                  <button
-                    type="button"
-                    className="btn-primary"
-                    onClick={handleDescSave}
-                    disabled={descSaving ||
-                      descDraft.length > VALIDATION.USER_DESCRIPTION_MAX}
-                  >
-                    {descSaving ? <Trans>Saving…</Trans> : <Trans>Save</Trans>}
-                  </button>
-                  <button
-                    type="button"
-                    className="btn-border"
-                    onClick={() => setDescEditing(false)}
-                    disabled={descSaving}
-                  >
-                    <Trans>Cancel</Trans>
-                  </button>
-                  {descError && (
-                    <ErrorCard title={t`Failed to save`} message={descError} />
-                  )}
-                </div>
-              </div>
+              <DescriptionEditor
+                initialDescription={profileUser.description ?? ""}
+                onCancel={() => setDescEditing(false)}
+                onSaved={handleDescSaved}
+              />
             )
             : (
               <div
@@ -956,11 +836,7 @@ export function UserPublicProfile() {
                   isOwnProfile ? " profile-description-view--editable" : ""
                 }`}
                 onClick={isOwnProfile
-                  ? () => {
-                    setDescDraft(profileUser.description ?? "");
-                    setDescError(null);
-                    setDescEditing(true);
-                  }
+                  ? () => setDescEditing(true)
                   : undefined}
               >
                 {profileUser.description
@@ -1548,3 +1424,136 @@ function FollowedUserCard({ user }: { user: PublicUser }) {
     </li>
   );
 }
+
+interface EmailEditorProps {
+  initialEmail: string;
+  onCancel: () => void;
+  onSaved: (email: string) => void;
+}
+
+function EmailEditor({ initialEmail, onCancel, onSaved }: EmailEditorProps) {
+  const { authFetch } = useAuth();
+  const form = useApiForm<{ email: string }>({
+    defaultValues: { email: initialEmail },
+  });
+  const email = form.watch("email");
+  const submitting = form.formState.isSubmitting;
+
+  const onSubmit = form.submit(async ({ email }) => {
+    await expectOk<RawPublicUser>(
+      await authFetch(`${API_URL}/api/users/me`, {
+        method: "PATCH",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify(
+          { email: email.trim() } satisfies UpdateUserRequest,
+        ),
+      }),
+    );
+    onSaved(email.trim());
+  });
+
+  return (
+    <FormProvider {...form}>
+      <form className="profile-email-editor" onSubmit={onSubmit}>
+        <input
+          type="email"
+          className="profile-email-input"
+          {...form.register("email")}
+          onKeyDown={(e) => {
+            if (e.key === "Escape") onCancel();
+          }}
+          disabled={submitting}
+          autoFocus
+        />
+        <div className="profile-email-actions">
+          <SubmitButton
+            className="profile-email-btn profile-email-btn--save"
+            pendingLabel={<Trans>Saving…</Trans>}
+            disabled={!email.trim()}
+          >
+            <Trans>Save</Trans>
+          </SubmitButton>
+          <button
+            type="button"
+            className="profile-email-btn profile-email-btn--cancel"
+            onClick={onCancel}
+            disabled={submitting}
+          >
+            <Trans>Cancel</Trans>
+          </button>
+        </div>
+        <FormError title={t`Failed to save`} />
+      </form>
+    </FormProvider>
+  );
+}
+
+interface DescriptionEditorProps {
+  initialDescription: string;
+  onCancel: () => void;
+  onSaved: (description: string | undefined) => void;
+}
+
+function DescriptionEditor(
+  { initialDescription, onCancel, onSaved }: DescriptionEditorProps,
+) {
+  const { authFetch } = useAuth();
+  const form = useApiForm<{ description: string }>({
+    defaultValues: { description: initialDescription },
+  });
+  const description = form.watch("description");
+  const submitting = form.formState.isSubmitting;
+
+  const onSubmit = form.submit(async ({ description }) => {
+    const trimmed = description.trim() || undefined;
+    await expectOk<RawPublicUser>(
+      await authFetch(`${API_URL}/api/users/me`, {
+        method: "PATCH",
+        headers: { "Content-Type": "application/json" },
+        body: JSON.stringify(
+          { description: trimmed } satisfies UpdateUserRequest,
+        ),
+      }),
+    );
+    onSaved(trimmed);
+  });
+
+  return (
+    <FormProvider {...form}>
+      <form className="profile-description-editor" onSubmit={onSubmit}>
+        <Controller
+          name="description"
+          control={form.control}
+          render={({ field }) => (
+            <TextEditor
+              className="comment-reply-textarea"
+              value={field.value}
+              onChange={field.onChange}
+              onSubmit={() => void onSubmit()}
+              placeholder={t`Who am I?`}
+              autoResize
+              maxLength={VALIDATION.USER_DESCRIPTION_MAX}
+            />
+          )}
+        />
+        <div className="profile-description-actions">
+          <SubmitButton
+            pendingLabel={<Trans>Saving…</Trans>}
+            disabled={description.length > VALIDATION.USER_DESCRIPTION_MAX}
+          >
+            <Trans>Save</Trans>
+          </SubmitButton>
+          <button
+            type="button"
+            className="form-cancel"
+            onClick={onCancel}
+            disabled={submitting}
+          >
+            <Trans>Cancel</Trans>
+          </button>
+          <FormError title={t`Failed to save`} />
+        </div>
+      </form>
+    </FormProvider>
+  );
+}

src/pages/UserRegister.tsx

@@ -1,5 +1,4 @@
 import { useEffect, useState } from "react";
-import type { SubmitEvent } from "react";
 import { Link, useNavigate, useSearchParams } from "react-router";
 import { t } from "@lingui/core/macro";
 import { Trans } from "@lingui/react/macro";
@@ -7,24 +6,31 @@ import { Trans } from "@lingui/react/macro";
 import { API_URL, VALIDATION } from "../config/api.ts";
 import {
   deserializeAuthResponse,
-  parseAPIResponse,
   type RawAuthResponse,
   type RegisterRequest,
 } from "../model.ts";
 import { useAuth } from "../hooks/useAuth.ts";
 import { PageShell } from "../components/PageShell.tsx";
 import { ErrorCard } from "../components/ErrorCard.tsx";
-import { friendlyFetchError } from "../utils/apiError.ts";
+import {
+  expectOk,
+  FormError,
+  FormProvider,
+  SubmitButton,
+  TextField,
+  useApiForm,
+} from "../components/form/index.ts";
 
 type TokenState =
   | { status: "checking" }
   | { status: "invalid" }
   | { status: "valid" };
 
-type FormState =
-  | { status: "idle" }
-  | { status: "submitting" }
-  | { status: "error"; error: string };
+interface Values {
+  username: string;
+  email: string;
+  password: string;
+}
 
 export function UserRegister() {
   const navigate = useNavigate();
@@ -35,9 +41,12 @@ export function UserRegister() {
   const [tokenState, setTokenState] = useState<TokenState>(() =>
     token ? { status: "checking" } : { status: "invalid" }
   );
-  const [formState, setFormState] = useState<FormState>({ status: "idle" });
   const [prevToken, setPrevToken] = useState(token);
 
+  const form = useApiForm<Values>({
+    defaultValues: { username: "", email: "", password: "" },
+  });
+
   if (prevToken !== token) {
     setPrevToken(token);
     setTokenState(token ? { status: "checking" } : { status: "invalid" });
@@ -52,41 +61,20 @@ export function UserRegister() {
       .catch(() => setTokenState({ status: "invalid" }));
   }, [token]);
 
-  const handleSubmit = async (e: SubmitEvent<HTMLFormElement>) => {
-    e.preventDefault();
-    setFormState({ status: "submitting" });
-
-    const formData = new FormData(e.currentTarget);
-    const username = formData.get("username") as string;
-    const password = formData.get("password") as string;
-    const email = formData.get("email") as string;
-
-    try {
-      const res = await fetch(`${API_URL}/api/users/register`, {
+  const onSubmit = form.submit(async ({ username, email, password }) => {
+    const data = await expectOk<RawAuthResponse>(
+      await fetch(`${API_URL}/api/users/register`, {
         method: "POST",
         headers: { "Content-Type": "application/json" },
         body: JSON.stringify(
-          {
-            username,
-            password,
-            inviteToken: token,
-            email,
-          } satisfies RegisterRequest,
+          { username, password, inviteToken: token, email } satisfies
+            RegisterRequest,
         ),
-      });
-
-      const apiResponse = parseAPIResponse<RawAuthResponse>(await res.json());
-
-      if (apiResponse.success) {
-        login(deserializeAuthResponse(apiResponse.data));
-        navigate("/");
-      } else {
-        setFormState({ status: "error", error: apiResponse.error.message });
-      }
-    } catch (err) {
-      setFormState({ status: "error", error: friendlyFetchError(err) });
-    }
-  };
+      }),
+    );
+    login(deserializeAuthResponse(data));
+    navigate("/");
+  });
 
   if (tokenState.status === "checking") {
     return (
@@ -118,48 +106,49 @@ export function UserRegister() {
           <Trans>Register</Trans>
         </h1>
 
-        {formState.status === "error" && (
-          <ErrorCard title={t`Registration failed`} message={formState.error} />
-        )}
-
-        <form onSubmit={handleSubmit} className="auth-form">
-          <input
-            name="username"
-            type="text"
-            placeholder={t`Username`}
-            required
-            pattern={`[a-zA-Z0-9_]{${VALIDATION.USERNAME_MIN},${VALIDATION.USERNAME_MAX}}`}
-            title={t`${VALIDATION.USERNAME_MIN}–${VALIDATION.USERNAME_MAX} characters: letters, numbers, or underscores`}
-            maxLength={VALIDATION.USERNAME_MAX}
-            disabled={formState.status === "submitting"}
-            autoFocus
-          />
-          <input
-            name="email"
-            type="email"
-            placeholder={t`Email address`}
-            required
-            disabled={formState.status === "submitting"}
-          />
-          <input
-            name="password"
-            type="password"
-            placeholder={t`Password (min. ${VALIDATION.PASSWORD_MIN} characters)`}
-            required
-            minLength={VALIDATION.PASSWORD_MIN}
-            maxLength={VALIDATION.PASSWORD_MAX}
-            disabled={formState.status === "submitting"}
-          />
-          <button
-            type="submit"
-            className="btn-primary"
-            disabled={formState.status === "submitting"}
-          >
-            {formState.status === "submitting"
-              ? <Trans>Registering…</Trans>
-              : <Trans>Register</Trans>}
-          </button>
-        </form>
+        <FormProvider {...form}>
+          <form onSubmit={onSubmit} className="form">
+            <FormError title={t`Registration failed`} />
+            <TextField<Values>
+              name="username"
+              placeholder={t`Username`}
+              autoFocus
+              maxLength={VALIDATION.USERNAME_MAX}
+              rules={{
+                required: true,
+                pattern: {
+                  value: new RegExp(
+                    `^[a-zA-Z0-9_]{${VALIDATION.USERNAME_MIN},${VALIDATION.USERNAME_MAX}}$`,
+                  ),
+                  message:
+                    t`${VALIDATION.USERNAME_MIN}–${VALIDATION.USERNAME_MAX} characters: letters, numbers, or underscores`,
+                },
+              }}
+            />
+            <TextField<Values>
+              name="email"
+              type="email"
+              placeholder={t`Email address`}
+              rules={{ required: true }}
+            />
+            <TextField<Values>
+              name="password"
+              type="password"
+              placeholder={t`Password (min. ${VALIDATION.PASSWORD_MIN} characters)`}
+              maxLength={VALIDATION.PASSWORD_MAX}
+              rules={{
+                required: true,
+                minLength: {
+                  value: VALIDATION.PASSWORD_MIN,
+                  message: t`At least ${VALIDATION.PASSWORD_MIN} characters`,
+                },
+              }}
+            />
+            <SubmitButton pendingLabel={<Trans>Registering…</Trans>}>
+              <Trans>Register</Trans>
+            </SubmitButton>
+          </form>
+        </FormProvider>
 
         <p className="auth-card-footer">
           <Trans>

src/themes/brutalist.css

@@ -176,7 +176,8 @@
 [data-style="brutalist"] .rich-content-thumbnail-btn,
 [data-style="brutalist"] .user-menu-trigger,
 [data-style="brutalist"] .nav-search-btn,
-[data-style="brutalist"] .auth-link-btn {
+[data-style="brutalist"] .auth-link-btn,
+[data-style="brutalist"] .form-cancel {
   border: none;
   box-shadow: none;
 }
@@ -186,7 +187,9 @@
 [data-style="brutalist"] .nav-search-btn:hover:not(:disabled),
 [data-style="brutalist"] .nav-search-btn:active,
 [data-style="brutalist"] .auth-link-btn:hover:not(:disabled),
-[data-style="brutalist"] .auth-link-btn:active {
+[data-style="brutalist"] .auth-link-btn:active,
+[data-style="brutalist"] .form-cancel:hover:not(:disabled),
+[data-style="brutalist"] .form-cancel:active {
   transform: none;
   box-shadow: none;
 }
@@ -287,10 +290,8 @@
   border-color: var(--color-border) !important;
 }
 
-[data-style="brutalist"] .dump-form input:focus,
-[data-style="brutalist"] .dump-form textarea:focus,
-[data-style="brutalist"] .auth-form input:focus,
-[data-style="brutalist"] .auth-form textarea:focus,
+[data-style="brutalist"] .form input:focus,
+[data-style="brutalist"] .form textarea:focus,
 [data-style="brutalist"] .mention-textarea-wrap textarea:focus {
   box-shadow: 2px 2px 0 var(--color-accent);
 }