import { describe, expect, test, vi } from "vitest";
import { screen, waitFor, within } from "@testing-library/react";
import { userEvent } from "@testing-library/user-event";
import { useState } from "react";
import { CommentThread } from "../../../components/comment/CommentThread.tsx";
import type { Session } from "../../../utils/auth/storage.ts";
import type { Comment } from "../../../../shared/comment.ts";
import { calls, fail, route } from "../../fetch.ts";
import { makeComment, makeSession, wire } from "../../fixtures.ts";
import { renderWithContexts } from "../../render.tsx";

const me = makeSession({ id: "me", username: "me" });
const mod = makeSession({ id: "mod", username: "mod", role: "moderator" });

function setup(initial: Comment[], session: Session | null = me, ws = {}) {
  const user = userEvent.setup();
  function Harness() {
    const [comments, setComments] = useState(initial);
    return (
      <CommentThread
        dumpId="d1"
        comments={comments}
        currentUser={session?.user ?? null}
        onCommentCreated={(c) => setComments((prev) => [...prev, c])}
        onCommentDeleted={(id) =>
          setComments((prev) =>
            prev.map((c) => c.id === id ? { ...c, deleted: true } : c)
          )}
        onCommentUpdated={(c) =>
          setComments((prev) => prev.map((x) => x.id === c.id ? c : x))}
      />
    );
  }
  renderWithContexts(<Harness />, { session, ws });
  return user;
}

const created = (over: Partial<Comment>) => (req: { body: unknown }) =>
  wire(
    makeComment({
      dumpId: "d1",
      userId: "me",
      authorUsername: "me",
      body: (req.body as { body: string }).body,
      ...over,
    }),
  );

describe("CommentThread", () => {
  test("counts visible comments and nests replies", () => {
    setup([
      makeComment({ id: "a", body: "top" }),
      makeComment({ id: "b", parentId: "a", body: "reply" }),
      makeComment({ id: "c", deleted: true, body: "" }),
    ]);
    expect(screen.getByRole("heading", { name: "2 comments" }))
      .toBeInTheDocument();
    const top = screen.getByText("top").closest("li")!;
    expect(within(top).getByText("reply")).toBeInTheDocument();
    expect(screen.getByText("[deleted]")).toBeInTheDocument();
  });

  test("guests read but can't write, reply or like", () => {
    setup([makeComment({ body: "hello" })], null);
    expect(screen.queryByPlaceholderText("Add a comment…")).not
      .toBeInTheDocument();
    expect(screen.queryByRole("button", { name: "Reply" })).not
      .toBeInTheDocument();
    expect(screen.getByRole("button", { name: "Like" })).toHaveAttribute(
      "aria-disabled",
      "true",
    );
  });

  test("posting a comment", async () => {
    route("POST /api/dumps/:id/comments", created({ id: "new" }));
    const user = setup([]);
    const box = screen.getByPlaceholderText("Add a comment…");
    expect(screen.getByRole("button", { name: "Post comment" })).toBeDisabled();
    await user.type(box, "First!");
    await user.click(screen.getByRole("button", { name: "Post comment" }));
    await screen.findByText("First!", { selector: ".comment-body *" });
    expect(box).toHaveValue("");
    expect(calls("POST /api/dumps/:id/comments")[0].body).toEqual({
      body: "First!",
    });
    expect(screen.getByRole("heading", { name: "1 comment" }))
      .toBeInTheDocument();
  });

  test("Ctrl+Enter posts too; blank text doesn't", async () => {
    route("POST /api/dumps/:id/comments", created({}));
    const user = setup([]);
    const box = screen.getByPlaceholderText("Add a comment…");
    await user.type(box, "   ");
    await user.keyboard("{Control>}{Enter}{/Control}");
    expect(calls("POST /api/dumps/:id/comments")).toHaveLength(0);
    await user.type(box, "ok");
    await user.keyboard("{Control>}{Enter}{/Control}");
    await waitFor(() =>
      expect(calls("POST /api/dumps/:id/comments")).toHaveLength(1)
    );
  });

  test("a failed post keeps the text and says why", async () => {
    route("POST /api/dumps/:id/comments", () => fail("Comment too long", 400));
    const user = setup([]);
    const box = screen.getByPlaceholderText("Add a comment…");
    await user.type(box, "text");
    await user.click(screen.getByRole("button", { name: "Post comment" }));
    const alert = await screen.findByRole("alert");
    expect(alert).toHaveTextContent("Failed to post comment");
    expect(alert).toHaveTextContent("Comment too long");
    expect(box).toHaveValue("text");
  });

  test("the top-level Cancel only shows with text, and clears it", async () => {
    const user = setup([]);
    expect(screen.queryByRole("button", { name: "Cancel" })).not
      .toBeInTheDocument();
    await user.type(screen.getByPlaceholderText("Add a comment…"), "draft");
    await user.click(screen.getByRole("button", { name: "Cancel" }));
    expect(screen.getByPlaceholderText("Add a comment…")).toHaveValue("");
  });

  test("replying", async () => {
    route("POST /api/dumps/:id/comments", created({ id: "r", parentId: "a" }));
    const user = setup([makeComment({ id: "a", body: "parent" })]);
    await user.click(screen.getByRole("button", { name: "Reply" }));
    const box = screen.getByPlaceholderText("Write a reply…");
    await waitFor(() => expect(box).toHaveFocus());
    await user.type(box, "child");
    await user.click(screen.getByRole("button", { name: "Post reply" }));
    await waitFor(() =>
      expect(screen.queryByPlaceholderText("Write a reply…")).not
        .toBeInTheDocument()
    );
    expect(calls("POST /api/dumps/:id/comments")[0].body).toEqual({
      body: "child",
      parentId: "a",
    });
    const parent = screen.getByText("parent").closest("li")!;
    expect(within(parent).getByText("child")).toBeInTheDocument();
  });

  test("Escape backs out of a reply", async () => {
    const user = setup([makeComment({ id: "a" })]);
    await user.click(screen.getByRole("button", { name: "Reply" }));
    await user.type(
      screen.getByPlaceholderText("Write a reply…"),
      "nah{Escape}",
    );
    expect(screen.queryByPlaceholderText("Write a reply…")).not
      .toBeInTheDocument();
  });

  test("editing your own comment", async () => {
    route(
      "PATCH /api/comments/:id",
      (req) =>
        wire(
          makeComment({
            id: "a",
            userId: "me",
            authorUsername: "me",
            body: (req.body as { body: string }).body,
            updatedAt: new Date(),
          }),
        ),
    );
    const user = setup([
      makeComment({ id: "a", userId: "me", authorUsername: "me", body: "old" }),
    ]);
    await user.click(screen.getByRole("button", { name: "Edit" }));
    const box = screen.getByDisplayValue("old");
    await user.clear(box);
    await user.type(box, "new");
    await user.click(screen.getByRole("button", { name: "Save" }));
    await screen.findByText("new");
    expect(screen.getByText(/^edited/)).toBeInTheDocument();
  });

  test("saving an edit unchanged doesn't stamp it edited", async () => {
    const user = setup([makeComment({ id: "a", userId: "me", body: "same" })]);
    await user.click(screen.getByRole("button", { name: "Edit" }));
    await user.click(screen.getByRole("button", { name: "Save" }));
    await waitFor(() =>
      expect(screen.queryByRole("button", { name: "Save" })).not
        .toBeInTheDocument()
    );
    expect(calls("PATCH /api/comments/:id")).toHaveLength(0);
  });

  test("only the author or a moderator can edit and delete", () => {
    const comments = [
      makeComment({ id: "mine", userId: "me", body: "mine" }),
      makeComment({ id: "theirs", userId: "them", body: "theirs" }),
    ];
    setup(comments);
    const theirs = screen.getByText("theirs").closest("li")!;
    expect(within(theirs).queryByRole("button", { name: "Edit" })).not
      .toBeInTheDocument();
    expect(within(theirs).queryByRole("button", { name: "Delete" })).not
      .toBeInTheDocument();
    const mine = screen.getByText("mine").closest("li")!;
    expect(within(mine).getByRole("button", { name: "Delete" }))
      .toBeInTheDocument();
  });

  test("a moderator can delete anyone's", () => {
    setup([makeComment({ userId: "them", body: "theirs" })], mod);
    expect(screen.getByRole("button", { name: "Delete" })).toBeInTheDocument();
  });

  test("deleting asks first", async () => {
    route(
      "DELETE /api/comments/:id",
      () => new Response(null, { status: 204 }),
    );
    const user = setup([makeComment({ id: "a", userId: "me", body: "bye" })]);
    await user.click(screen.getByRole("button", { name: "Delete" }));
    const dialog = screen.getByRole("alertdialog");
    expect(dialog).toHaveTextContent("Delete this comment?");
    await user.click(within(dialog).getByRole("button", { name: "Delete" }));
    await screen.findByText("[deleted]");
  });

  test("a failed delete says so", async () => {
    route("DELETE /api/comments/:id", () => fail("Forbidden", 403));
    const user = setup([makeComment({ id: "a", userId: "me", body: "stays" })]);
    await user.click(screen.getByRole("button", { name: "Delete" }));
    await user.click(
      within(screen.getByRole("alertdialog")).getByRole("button", {
        name: "Delete",
      }),
    );
    expect(await screen.findByRole("alert")).toHaveTextContent(
      /couldn't be deleted/i,
    );
    expect(screen.getByText("stays")).toBeInTheDocument();
  });

  test("likes come from the live counts", async () => {
    const castCommentLike = vi.fn();
    const user = setup([makeComment({ id: "a", likeCount: 1 })], me, {
      likeCounts: { a: 5 },
      castCommentLike,
    });
    expect(screen.getByText("5")).toBeInTheDocument();
    await user.click(screen.getByRole("button", { name: "Like" }));
    expect(castCommentLike).toHaveBeenCalledWith("a", 5);
  });

  test("the timestamp links to the comment", () => {
    setup([makeComment({ id: "a" })]);
    expect(screen.getByRole("link", { name: /ago/ })).toHaveAttribute(
      "href",
      "/#comment-a",
    );
  });
});