// Small pure helpers: slugs, pagination, permissions, rate limiting, image
// sniffing, self-links and the favicon codepoint.
import "./setup.ts";
import {
  assert,
  assertEquals,
  assertFalse,
  assertMatch,
  assertThrows,
} from "@std/assert";
import { FakeTime } from "@std/testing/time";
import { makeSlug, slugify, UUID_RE } from "../lib/slugify.ts";
import {
  isReservedSlug,
  isSlugAvailable,
  isValidSlugFormat,
} from "../lib/reserved-slugs.ts";
import { parsePagination } from "../lib/pagination.ts";
import { can, hasPermission, ROLE_PERMISSIONS } from "../lib/permissions.ts";
import { takeToken } from "../lib/rate-limit.ts";
import { detectImageMime, validateImageUpload } from "../lib/upload.ts";
import { isSelfUrl } from "../lib/self-url.ts";
import { emojiToCodepoint } from "../lib/site-icons.ts";
import { APIException } from "../model/interfaces.ts";
import { PNG } from "./helpers.ts";

Deno.test("slugify: lowercases, strips accents, dashes the rest", () => {
  assertEquals(slugify("Hello, World!"), "hello-world");
  assertEquals(slugify("Crème brûlée à Paris"), "creme-brulee-a-paris");
  assertEquals(slugify("  --already--dashed--  "), "already-dashed");
  assertEquals(slugify("日本語"), "untitled");
  assertEquals(slugify(""), "untitled");
  assertEquals(slugify("x".repeat(100)).length, 60);
});

Deno.test("makeSlug: suffixes the first 8 characters of the id", () => {
  const id = "0123abcd-0000-4000-8000-000000000000";
  assertEquals(makeSlug("My Song", id), "my-song-0123abcd");
  assert(UUID_RE.test(id));
  assertFalse(UUID_RE.test("my-song-0123abcd"));
});

Deno.test("category slugs: format and reserved words", () => {
  assert(isValidSlugFormat("music"));
  assert(isValidSlugFormat("lo-fi-2"));
  for (const bad of ["Music", "-music", "music-", "lo--fi", "lo fi", ""]) {
    assertFalse(isValidSlugFormat(bad), bad);
  }
  assert(isReservedSlug("dumps"));
  assert(isReservedSlug("api"));
  assertFalse(isReservedSlug("music"));
  assert(isSlugAvailable("music"));
  assertFalse(isSlugAvailable("users"));
  assertFalse(isSlugAvailable("Nope"));
});

Deno.test("parsePagination: defaults, bounds and garbage", () => {
  const p = (q: string, def?: number) =>
    parsePagination(new URLSearchParams(q), def);
  assertEquals(p(""), { page: 1, limit: 20 });
  assertEquals(p("page=3&limit=5"), { page: 3, limit: 5 });
  assertEquals(p("page=0&limit=0"), { page: 1, limit: 20 });
  assertEquals(p("page=-4&limit=-1"), { page: 1, limit: 1 });
  assertEquals(p("limit=1000"), { page: 1, limit: 100 });
  assertEquals(p("page=abc&limit=xyz"), { page: 1, limit: 20 });
  assertEquals(p("", 7), { page: 1, limit: 7 });
});

Deno.test("permissions: admin has all, moderator moderates, user nothing", () => {
  for (const perm of ROLE_PERMISSIONS.admin) {
    assert(hasPermission("admin", perm));
  }
  assert(hasPermission("moderator", "dump:moderate"));
  assert(hasPermission("moderator", "chat:moderate"));
  assertFalse(hasPermission("moderator", "user:manage"));
  assertFalse(hasPermission("moderator", "category:manage"));
  assertEquals(ROLE_PERMISSIONS.user, []);
  assert(
    can({ userId: "x", username: "x", role: "admin", exp: 0 }, "user:manage"),
  );
  assertFalse(
    can({ userId: "x", username: "x", role: "user", exp: 0 }, "dump:moderate"),
  );
});

Deno.test("takeToken: bursts to capacity, then refills over time", () => {
  using time = new FakeTime();
  const key = `test:${crypto.randomUUID()}`;
  const limit = { capacity: 3, refill: 1 }; // one token a second
  assert(takeToken(key, limit));
  assert(takeToken(key, limit));
  assert(takeToken(key, limit));
  assertFalse(takeToken(key, limit));
  time.tick(500);
  assertFalse(takeToken(key, limit));
  time.tick(500);
  assert(takeToken(key, limit));
  assertFalse(takeToken(key, limit));
  // Refill never exceeds capacity.
  time.tick(60_000);
  assert(takeToken(key, limit));
  assert(takeToken(key, limit));
  assert(takeToken(key, limit));
  assertFalse(takeToken(key, limit));
  // Keys are independent.
  assert(takeToken(`${key}:other`, limit));
});

Deno.test("detectImageMime: sniffs magic bytes, not names", () => {
  assertEquals(detectImageMime(PNG), "image/png");
  assertEquals(
    detectImageMime(new Uint8Array([0xff, 0xd8, 0xff, 0xe0])),
    "image/jpeg",
  );
  assertEquals(
    detectImageMime(new TextEncoder().encode("GIF89a")),
    "image/gif",
  );
  assertEquals(
    detectImageMime(new TextEncoder().encode("RIFF\0\0\0\0WEBPVP8 ")),
    "image/webp",
  );
  assertEquals(
    detectImageMime(new TextEncoder().encode("RIFF\0\0\0\0WAVEfmt ")),
    null,
  );
  assertEquals(
    detectImageMime(new TextEncoder().encode("<svg xmlns=...>")),
    null,
  );
  assertEquals(detectImageMime(new Uint8Array()), null);
});

Deno.test("validateImageUpload: rejects non-images and anything over 5 MB", () => {
  assertEquals(validateImageUpload(PNG), "image/png");
  assertThrows(
    () => validateImageUpload(new TextEncoder().encode("<html>")),
    APIException,
    "not a recognised image",
  );
  const big = new Uint8Array(5 * 1024 * 1024 + 1);
  big.set(PNG);
  assertThrows(() => validateImageUpload(big), APIException, "too large");
});

Deno.test("isSelfUrl: this site's dump, user and playlist pages only", () => {
  // GERBEUR_PUBLIC_URL is http://gerbeur.test in the suite.
  assert(isSelfUrl(new URL("http://gerbeur.test/dumps/abc")));
  assert(isSelfUrl(new URL("https://GERBEUR.test/users/bob")));
  assert(isSelfUrl(new URL("http://gerbeur.test/playlists/p-1")));
  assertFalse(isSelfUrl(new URL("http://gerbeur.test/dumps/abc/edit")));
  assertFalse(isSelfUrl(new URL("http://gerbeur.test/search")));
  assertFalse(isSelfUrl(new URL("http://elsewhere.test/users/bob")));
});

Deno.test("emojiToCodepoint: Twemoji file naming", () => {
  assertEquals(emojiToCodepoint("🚚"), "1f69a");
  // A lone variation selector is dropped…
  assertEquals(emojiToCodepoint("❤️"), "2764");
  // …but kept inside a ZWJ sequence.
  assertMatch(emojiToCodepoint("🏳️‍🌈"), /^1f3f3-fe0f-200d-1f308$/);
});