import { NextResponse } from 'next/server';
import { z } from 'zod';
import { runScan } from '@/lib/ai/scanner';
import { aiErrorMessage, clientIpHash, consumeQuota, currentUserId, getAnonId } from '@/lib/ai/request';

export const runtime = 'nodejs';
export const maxDuration = 120;

const Body = z.object({
  mode: z.enum(['photo', 'url', 'text']),
  images: z.array(z.object({ data: z.string().min(100).max(2_800_000), mediaType: z.enum(['image/jpeg', 'image/png', 'image/webp']) })).max(5).optional(),
  thumbnails: z.array(z.string().max(80_000)).max(3).optional(),
  url: z.string().url().max(2000).optional(),
  text: z.string().max(4000).optional(),
});

export async function POST(req: Request) {
  let body: z.infer<typeof Body>;
  try {
    body = Body.parse(await req.json());
  } catch (err) {
    return NextResponse.json({ error: 'Invalid request', detail: err instanceof Error ? err.message : String(err) }, { status: 400 });
  }
  if (body.mode === 'photo' && !body.images?.length) return NextResponse.json({ error: 'Add at least one photo' }, { status: 400 });
  if (body.mode === 'url' && !body.url) return NextResponse.json({ error: 'Paste a listing URL' }, { status: 400 });
  if (body.mode === 'text' && !body.text?.trim()) return NextResponse.json({ error: 'Describe the item' }, { status: 400 });

  const [userId, ipHash, anonId] = await Promise.all([currentUserId(), clientIpHash(), getAnonId()]);
  const quota = await consumeQuota('scanner', { userId, ipHash });
  if (!quota.ok) return NextResponse.json({ error: `Daily scanner limit reached (${quota.limit}). Sign in for a higher limit.` }, { status: 429 });

  try {
    const result = await runScan({
      mode: body.mode,
      images: body.images?.map((i) => ({ data: i.data, mediaType: i.mediaType })),
      thumbnails: body.thumbnails,
      url: body.url,
      text: body.text,
      userId,
      anonId,
      ipHash,
    });
    return NextResponse.json({ ...result, quota: { used: quota.used, limit: quota.limit } });
  } catch (err) {
    const e = aiErrorMessage(err);
    return NextResponse.json({ error: e.message }, { status: e.status });
  }
}