import {
  captureEmails,
  createUser,
  db,
  insertComment,
  insertDump,
  insertPlaylist,
  post,
  test,
} from "../helpers.ts";
import { assert, assertEquals, assertFalse } from "@std/assert";
import {
  buildDigest,
  PERIOD_MS,
  sendDueDigests,
  syncDigestSchedules,
} from "../../services/digest-service.ts";
import {
  getSettings,
  updateSettings,
} from "../../services/settings-service.ts";

const DAY = 86_400_000;
const ago = (ms: number) => new Date(Date.now() - ms).toISOString();
const week = () =>
  [new Date(Date.now() - 7 * DAY), new Date(Date.now() + 60_000)] as const;

function notify(
  userId: string,
  type: string,
  data: object,
  createdAt = ago(DAY),
) {
  db.prepare(
    `INSERT INTO notifications (id, user_id, type, data, read, created_at) VALUES (?, ?, ?, ?, 0, ?);`,
  ).run(crypto.randomUUID(), userId, type, JSON.stringify(data), createdAt);
}

function follow(
  followerId: string,
  target: { user?: string; playlist?: string },
) {
  db.prepare(
    `INSERT INTO follows (id, follower_id, followed_user_id, followed_playlist_id, created_at) VALUES (?, ?, ?, ?, ?);`,
  ).run(
    crypto.randomUUID(),
    followerId,
    target.user ?? null,
    target.playlist ?? null,
    ago(DAY),
  );
}

function vote(dumpId: string, n: number) {
  db.prepare(`UPDATE dumps SET vote_count = ? WHERE id = ?;`).run(n, dumpId);
}

function schedule(userId: string, cadence: string, windowStart: string) {
  db.prepare(
    `INSERT OR REPLACE INTO digest_schedule (user_id, cadence, window_start) VALUES (?, ?, ?);`,
  ).run(userId, cadence, windowStart);
}

const windowOf = (userId: string, cadence: string) =>
  (db.prepare(
    `SELECT window_start FROM digest_schedule WHERE user_id = ? AND cadence = ?;`,
  ).get(userId, cadence) as { window_start: string } | undefined)?.window_start;

test("buildDigest: the weekly digest gathers activity, network, top and community", async () => {
  const reader = await createUser();
  const friend = await createUser({ invitedBy: reader.id });
  const stranger = await createUser();
  const mine = insertDump({ userId: reader.id, title: "My dump" });
  vote(mine.id, 3);
  const commentId = insertComment({
    dumpId: mine.id,
    userId: friend.id,
    body: "Loved **this** [link](https://x.test)",
  });
  notify(reader.id, "dump_commented", {
    commenterId: friend.id,
    commenterUsername: friend.username,
    commentId,
    dumpId: mine.id,
    dumpTitle: "My dump",
  });
  notify(reader.id, "user_followed", {
    followerId: friend.id,
    followerUsername: friend.username,
  });
  for (let i = 0; i < 3; i++) {
    notify(reader.id, "dump_upvoted", {
      voterId: friend.id,
      voterUsername: friend.username,
      dumpId: mine.id,
      dumpTitle: "My dump",
    });
  }
  // Before the period: not counted.
  notify(reader.id, "user_followed", { followerUsername: "old" }, ago(9 * DAY));

  follow(reader.id, { user: friend.id });
  const posted = insertDump({ userId: friend.id, title: "Friend's post" });
  vote(posted.id, 5);
  insertDump({ userId: friend.id, title: "Private", isPrivate: true });
  insertDump({ userId: friend.id, title: "Too old", createdAt: ago(10 * DAY) });
  const mix = insertPlaylist({ userId: stranger.id, title: "Mix" });
  follow(reader.id, { playlist: mix.id });
  const added = insertDump({ userId: stranger.id, title: "Added <b>" });
  db.prepare(
    `INSERT INTO playlist_dumps (playlist_id, dump_id, position, added_at) VALUES (?, ?, 0, ?);`,
  ).run(mix.id, added.id, ago(DAY));
  // Posted by someone followed and added to a followed playlist: listed once.
  db.prepare(
    `INSERT INTO playlist_dumps (playlist_id, dump_id, position, added_at) VALUES (?, ?, 1, ?);`,
  ).run(mix.id, posted.id, ago(DAY));

  const [from, to] = week();
  const digest =
    (buildDigest(reader.id, reader.username, "weekly", from, to, "tok"))!;

  assertEquals(digest.activity?.counts, {
    comments: 1,
    followers: 1,
    upvotes: 3,
  });
  assertEquals(digest.activity?.total, 5);
  assertEquals(digest.activity?.highlights.map((h) => h.kind), [
    "comment",
    "userFollow",
  ]);
  assertEquals(digest.activity?.highlights[0].quote, "Loved this link");

  assertEquals(digest.network?.dumps.map((d) => [d.title, d.addedTo]), [
    ["Friend's post", undefined],
    ["Added <b>", "Mix"],
  ]);
  assertEquals(digest.top.map((d) => [d.title, d.mine]), [
    ["Friend's post", false],
    ["My dump", true],
  ]);
  assertEquals(
    digest.community?.members.map((m) => [m.username, m.invitedBy]),
    [
      [friend.username, reader.username],
      [stranger.username, null],
    ],
  );
  assertEquals(digest.community?.totals.dumps, 3);
  assert(digest.links.unsubscribe.includes("/unsubscribe?token="));
});

test("buildDigest: the monthly recap has no personal sections, and nothing makes no digest", async () => {
  const reader = await createUser({ createdAt: ago(40 * DAY) });
  const [from, to] = [
    new Date(Date.now() - 30 * DAY),
    new Date(Date.now() + 60_000),
  ];
  assertEquals(
    buildDigest(reader.id, reader.username, "monthly", from, to, "tok"),
    null,
  );

  const other = await createUser({ createdAt: ago(40 * DAY) });
  notify(reader.id, "user_followed", { followerUsername: other.username });
  const d = insertDump({ userId: other.id, title: "Hit" });
  vote(d.id, 2);
  insertDump({ userId: other.id, title: "No votes" });
  const recap =
    (buildDigest(reader.id, reader.username, "monthly", from, to, "tok"))!;
  assertEquals(recap.activity, null);
  assertEquals(recap.network, null);
  assertEquals(recap.top.map((t) => t.title), ["Hit"]);
});

test("sendDueDigests: sends what's due in the reader's style, once, and moves the period on", async () => {
  using mail = captureEmails();
  const reader = await createUser({ createdAt: ago(20 * DAY) });
  const other = await createUser({ createdAt: ago(20 * DAY) });
  updateSettings(reader.id, { style: "geocities", colorScheme: "dark" });
  const d = insertDump({
    userId: other.id,
    title: "Worth a look",
    createdAt: ago(3 * DAY),
  });
  vote(d.id, 1);
  const start = ago(PERIOD_MS.weekly + DAY);
  schedule(reader.id, "weekly", start);
  schedule(reader.id, "monthly", ago(DAY));
  schedule(other.id, "weekly", ago(DAY));
  schedule(other.id, "monthly", ago(DAY));

  assertEquals(await sendDueDigests(), 1);
  assertEquals(mail.sent.length, 1);
  const email = mail.sent[0];
  assertEquals(email.to, reader.email);
  assert(email.subject.startsWith("Your week on gerbeur"));
  assert(email.html.includes("Worth a look"));
  assert(email.html.includes("#1b1b46"), "GeoCities' dark card");
  assertFalse(email.html.includes("prefers-color-scheme"));
  assertEquals(
    email.headers?.["List-Unsubscribe-Post"],
    "List-Unsubscribe=One-Click",
  );
  assertEquals(
    windowOf(reader.id, "weekly"),
    new Date(new Date(start).getTime() + PERIOD_MS.weekly).toISOString(),
  );

  // Nothing is due any more.
  assertEquals(await sendDueDigests(), 0);

  // The header's link turns the weekly digest off, in one click.
  const link = email.headers!["List-Unsubscribe"].slice(1, -1);
  const res = await post(new URL(link).pathname + new URL(link).search, {
    headers: { "Content-Type": "application/x-www-form-urlencoded" },
  });
  assertEquals(res.status, 200);
  assertEquals(getSettings(reader.id).digestWeekly, false);
  assertEquals(getSettings(reader.id).digestMonthly, true);
  syncDigestSchedules(new Date());
  assertEquals(windowOf(reader.id, "weekly"), undefined);
});

test("sendDueDigests: an empty digest isn't sent, a late one covers the last period, and admin@localhost is skipped", async () => {
  using mail = captureEmails();
  const quiet = await createUser({ createdAt: ago(60 * DAY) });
  schedule(quiet.id, "weekly", ago(PERIOD_MS.weekly + DAY));
  assertEquals(await sendDueDigests(), 0);
  assert(windowOf(quiet.id, "weekly")! > ago(2 * DAY));

  const late = await createUser({ createdAt: ago(60 * DAY) });
  const d = insertDump({ userId: quiet.id, title: "Recent" });
  vote(d.id, 1);
  schedule(late.id, "weekly", ago(5 * PERIOD_MS.weekly));
  const local = await createUser({
    email: "admin@localhost",
    createdAt: ago(60 * DAY),
  });
  schedule(local.id, "weekly", ago(PERIOD_MS.weekly + DAY));
  const before = Date.now();
  // Quiet's next period has only begun.
  assertEquals(await sendDueDigests(), 1);
  assertEquals(mail.sent.map((m) => m.to), [late.email]);
  // The late one's period is the last week, so the next starts now.
  assert(new Date(windowOf(late.id, "weekly")!).getTime() >= before);
  assert(windowOf(local.id, "weekly")! > ago(2 * DAY));
});

test("syncDigestSchedules: new users start now, a turned-off cadence loses its row", async () => {
  const user = await createUser();
  const now = new Date();
  syncDigestSchedules(now);
  assertEquals(windowOf(user.id, "weekly"), now.toISOString());
  assertEquals(windowOf(user.id, "monthly"), now.toISOString());
  updateSettings(user.id, { digestMonthly: false });
  syncDigestSchedules(new Date(now.getTime() + 1000));
  assertEquals(windowOf(user.id, "weekly"), now.toISOString());
  assertEquals(windowOf(user.id, "monthly"), undefined);
});

test("unsubscribe: a bad or other kind of token is refused", async () => {
  const user = await createUser();
  assertEquals((await post("/api/users/unsubscribe?token=nope")).status, 400);
  assertEquals(
    (await post(`/api/users/unsubscribe?token=${user.token}`)).status,
    400,
  );
  assertEquals((await post("/api/users/unsubscribe")).status, 400);
});