import { NextRequest } from 'next/server';
import { db } from '@/lib/db';
import { auth } from '@/lib/auth';
import { apiErrors, successResponse } from '@/lib/api-response';
import { checkRateLimit, rateLimitHeaders, RATE_LIMIT_CONFIGS } from '@/lib/rate-limit';

const MAX_Q_LENGTH = 100;
const RESULTS_PER_CATEGORY = 5;

// GET /api/search?q=term — search projects, workspaces, and videos accessible to the user
export async function GET(request: NextRequest) {
  try {
    const session = await auth();
    if (!session?.user?.id) {
      return apiErrors.unauthorized();
    }

    const userId = session.user.id;

    const cfg = RATE_LIMIT_CONFIGS['search'];
    const rl = await checkRateLimit(userId, 'search', cfg);
    if (!rl.allowed) {
      return new Response(
        JSON.stringify({ error: 'Too many requests. Please try again later.' }),
        { status: 429, headers: { 'Content-Type': 'application/json', ...rateLimitHeaders(rl, cfg.maxRequests) } }
      );
    }

    const { searchParams } = new URL(request.url);
    const term = (searchParams.get('q') ?? '').trim();

    if (term.length < 2) {
      return successResponse({ projects: [], workspaces: [], videos: [] });
    }

    if (term.length > MAX_Q_LENGTH) {
      return apiErrors.badRequest('Query too long.');
    }

    // Access filter reused across queries
    const projectAccessFilter = {
      OR: [
        { ownerId: userId },
        { members: { some: { userId } } },
        { workspace: { members: { some: { userId } } } },
      ],
    };

    const workspaceAccessFilter = {
      OR: [
        { ownerId: userId },
        { members: { some: { userId } } },
      ],
    };

    const [projects, workspaces, videos] = await Promise.all([
      db.project.findMany({
        where: {
          AND: [
            projectAccessFilter,
            {
              OR: [
                { name: { contains: term, mode: 'insensitive' } },
                { description: { contains: term, mode: 'insensitive' } },
              ],
            },
          ],
        },
        select: {
          id: true,
          name: true,
          description: true,
          workspace: { select: { id: true, name: true } },
        },
        take: RESULTS_PER_CATEGORY,
      }),

      db.workspace.findMany({
        where: {
          AND: [
            workspaceAccessFilter,
            {
              OR: [
                { name: { contains: term, mode: 'insensitive' } },
                { description: { contains: term, mode: 'insensitive' } },
              ],
            },
          ],
        },
        select: {
          id: true,
          name: true,
          description: true,
        },
        take: RESULTS_PER_CATEGORY,
      }),

      db.video.findMany({
        where: {
          project: projectAccessFilter,
          title: { contains: term, mode: 'insensitive' },
        },
        select: {
          id: true,
          title: true,
          projectId: true,
          project: { select: { id: true, name: true } },
        },
        take: RESULTS_PER_CATEGORY,
      }),
    ]);

    const response = successResponse({ projects, workspaces, videos });
    response.headers.set('Cache-Control', 'private, no-store');
    return response;
  } catch (err) {
    console.error('[search] error:', err);
    return apiErrors.internalError();
  }
}