import { createServerFn } from "@tanstack/react-start";
import { assertBelowCap, CAPS } from "~/server/limits";
import { z } from "zod";
import { requireViewer, viewerMiddleware } from "./middleware";
import { all, batch, first, placeholders, run, stmt } from "~/server/db";
import { randomId } from "~/server/crypto";
import { requireRepoAccess } from "~/server/repos";
import { loadIssue, applyLabels, issueUrl } from "~/server/issues";
import { addIssueEvent } from "~/server/pulls";
import { emitNotification } from "~/server/events/emit";
import { notFoundError } from "~/server/errors";
import { labelColor, repoRef } from "~/lib/validation";
import type { LabelInfo } from "./issues";

export const setIssueLabels = createServerFn({ method: "POST" })
  .middleware([viewerMiddleware])
  .validator(repoRef.extend({ number: z.number().int(), labels: z.array(z.string()).max(50) }))
  .handler(async ({ data, context }) => {
    const viewer = requireViewer(context.viewer);
    const access = await requireRepoAccess(data.owner, data.repo, viewer, "write");
    const issue = await loadIssue(access.repo.id, data.number);
    if (!issue) throw notFoundError("Issue not found");
    await applyLabels(access.repo.id, issue.id, data.labels);
    await addIssueEvent(issue.id, viewer.id, "labeled", { labels: data.labels });
    return { ok: true };
  });

export const setIssueAssignees = createServerFn({ method: "POST" })
  .middleware([viewerMiddleware])
  .validator(repoRef.extend({ number: z.number().int(), usernames: z.array(z.string()).max(10) }))
  .handler(async ({ data, context }) => {
    const viewer = requireViewer(context.viewer);
    const access = await requireRepoAccess(data.owner, data.repo, viewer, "write");
    const issue = await loadIssue(access.repo.id, data.number);
    if (!issue) throw notFoundError("Issue not found");
    const users = data.usernames.length
      ? await all<{ id: string }>(
          `SELECT a.id FROM accounts a JOIN users u ON u.account_id = a.id WHERE a.name IN (${placeholders(data.usernames.length)})`,
          ...data.usernames,
        )
      : [];
    await batch([
      stmt("DELETE FROM issue_assignees WHERE issue_id = ?", issue.id),
      ...users.map((user) => stmt("INSERT INTO issue_assignees (issue_id, user_id) VALUES (?, ?)", issue.id, user.id)),
    ]);
    await addIssueEvent(issue.id, viewer.id, "assigned", { usernames: data.usernames });
    if (users.length > 0) {
      await emitNotification({
        repoId: access.repo.id,
        issueId: null,
        actorId: viewer.id,
        reason: "assigned",
        title: `You were assigned ${access.repo.owner_name}/${access.repo.name}#${issue.number}`,
        url: issueUrl(access.repo, issue),
        mentionText: null,
        directRecipients: users.map((user) => user.id),
      });
    }
    return { ok: true };
  });

export const setIssueLock = createServerFn({ method: "POST" })
  .middleware([viewerMiddleware])
  .validator(repoRef.extend({ number: z.number().int(), locked: z.boolean() }))
  .handler(async ({ data, context }) => {
    const viewer = requireViewer(context.viewer);
    const access = await requireRepoAccess(data.owner, data.repo, viewer, "write");
    const issue = await loadIssue(access.repo.id, data.number);
    if (!issue) throw notFoundError("Issue not found");
    await run("UPDATE issues SET locked = ? WHERE id = ?", data.locked ? 1 : 0, issue.id);
    await addIssueEvent(issue.id, viewer.id, data.locked ? "locked" : "unlocked", {});
    return { ok: true };
  });

export const listLabels = createServerFn({ method: "GET" })
  .middleware([viewerMiddleware])
  .validator(repoRef)
  .handler(async ({ data, context }) => {
    const { repo } = await requireRepoAccess(data.owner, data.repo, context.viewer, "read");
    return all<LabelInfo & { open_count: number }>(
      `SELECT l.id, l.name, l.color, l.description,
         (SELECT COUNT(*) FROM issue_labels il JOIN issues i ON i.id = il.issue_id WHERE il.label_id = l.id AND i.state = 'open') AS open_count
       FROM labels l WHERE l.repo_id = ? ORDER BY l.name`,
      repo.id,
    );
  });

export const saveLabel = createServerFn({ method: "POST" })
  .middleware([viewerMiddleware])
  .validator(
    repoRef.extend({
      id: z.string().nullable(),
      name: z.string().trim().min(1).max(50),
      color: labelColor,
      description: z.string().max(100).nullable(),
    }),
  )
  .handler(async ({ data, context }) => {
    const { repo } = await requireRepoAccess(data.owner, data.repo, context.viewer, "write");
    if (!data.id)
      assertBelowCap(
        (await first<{ count: number }>("SELECT COUNT(*) AS count FROM labels WHERE repo_id = ?", repo.id))?.count ?? 0,
        CAPS.labelsPerRepo,
        "labels",
      );
    if (data.id) {
      await run(
        "UPDATE labels SET name = ?, color = ?, description = ? WHERE id = ? AND repo_id = ?",
        data.name,
        data.color,
        data.description,
        data.id,
        repo.id,
      );
    } else {
      await run(
        "INSERT INTO labels (id, repo_id, name, color, description) VALUES (?, ?, ?, ?, ?)",
        randomId(),
        repo.id,
        data.name,
        data.color,
        data.description,
      );
    }
    return { ok: true };
  });

export const deleteLabel = createServerFn({ method: "POST" })
  .middleware([viewerMiddleware])
  .validator(repoRef.extend({ id: z.string() }))
  .handler(async ({ data, context }) => {
    const { repo } = await requireRepoAccess(data.owner, data.repo, context.viewer, "write");
    await run("DELETE FROM labels WHERE id = ? AND repo_id = ?", data.id, repo.id);
    return { ok: true };
  });

export const listAssignable = createServerFn({ method: "GET" })
  .middleware([viewerMiddleware])
  .validator(repoRef)
  .handler(async ({ data, context }) => {
    const { repo } = await requireRepoAccess(data.owner, data.repo, context.viewer, "read");
    return all<{ name: string }>(
      `SELECT a.name FROM accounts a WHERE a.id = ?1 AND a.kind = 'user'
       UNION SELECT a.name FROM collaborators c JOIN accounts a ON a.id = c.user_id WHERE c.repo_id = ?2
       UNION SELECT a.name FROM org_members m JOIN accounts a ON a.id = m.user_id WHERE m.org_id = ?1
       ORDER BY 1`,
      repo.owner_id,
      repo.id,
    );
  });