import { repoDb, stmt } from "./scoped-db";
import { addIssueEvent } from "./pulls";
import type { PullRow } from "./pulls";
import { ownerAccountIds, ownersToRequest, pullCodeOwners } from "./codeowners";
import { accountsById } from "./people";
import { emitNotification } from "./events/emit";
import { pullUrl } from "./pull-access";
import type { RepoRow, Viewer } from "~/lib/types";
import { issuesChanged } from "./repo-state";

async function notifyRequested(repo: RepoRow, pull: PullRow, actor: Viewer, userIds: string[]) {
  await emitNotification({
    repoId: repo.id,
    issueId: null,
    actorId: actor.id,
    reason: "review_requested",
    title: `${actor.name} requested your review on ${repo.owner_name}/${repo.name}#${pull.number}`,
    url: pullUrl(repo, pull.number),
    mentionText: null,
    directRecipients: userIds,
  });
}

/** Auto-requests reviews from CODEOWNERS of the changed files who have not reviewed yet. */
export async function requestCodeOwnerReviews(
  pull: PullRow,
  baseRepo: RepoRow,
  headRepo: RepoRow,
  actor: Viewer,
): Promise<void> {
  const { owned } = await pullCodeOwners(pull, baseRepo, headRepo);
  if (owned.size === 0) return;
  const candidates = ownersToRequest(owned, await ownerAccountIds(owned), pull.author_id);
  if (candidates.length === 0) return;
  const reviewed = new Set(
    (
      await repoDb(pull.repo_id).all<{ author_id: string }>(
        "SELECT DISTINCT author_id FROM reviews WHERE issue_id = ? AND state != 'dismissed'",
        pull.issue_id,
      )
    ).map((row) => row.author_id),
  );
  const wanted = candidates.filter((id) => !reviewed.has(id));
  if (wanted.length === 0) return;
  const now = Date.now();
  await repoDb(pull.repo_id).batch(
    wanted.map((id) =>
      stmt(
        "INSERT OR IGNORE INTO review_requests (issue_id, user_id, created_at, code_owner) VALUES (?, ?, ?, 1)",
        pull.issue_id,
        id,
        now,
      ),
    ),
  );
  const people = await accountsById(wanted);
  await addIssueEvent(pull, actor.id, "review_requested", {
    usernames: wanted.map((id) => people.get(id)?.name ?? "ghost"),
    codeOwners: true,
  });
  issuesChanged(baseRepo.id, [pull.issue_id]);
  await notifyRequested(baseRepo, pull, actor, wanted);
}

/** Asks a previous reviewer to look again after new changes. */
export async function rerequestReview(repo: RepoRow, pull: PullRow, actor: Viewer, userId: string): Promise<boolean> {
  const db = repoDb(pull.repo_id);
  const reviewed = await db.first(
    "SELECT 1 FROM reviews WHERE issue_id = ? AND author_id = ? LIMIT 1",
    pull.issue_id,
    userId,
  );
  if (!reviewed) return false;
  await db.run(
    `INSERT INTO review_requests (issue_id, user_id, created_at) VALUES (?, ?, ?)
     ON CONFLICT (issue_id, user_id) DO UPDATE SET created_at = excluded.created_at`,
    pull.issue_id,
    userId,
    Date.now(),
  );
  issuesChanged(repo.id, [pull.issue_id]);
  const people = await accountsById([userId]);
  await addIssueEvent(pull, actor.id, "review_requested", {
    usernames: [people.get(userId)?.name ?? "ghost"],
    rerequested: true,
  });
  await notifyRequested(repo, pull, actor, [userId]);
  return true;
}