import { NextResponse } from 'next/server';
import { createAdminClient } from '@/lib/supabase/admin';
import { createClient } from '@/lib/supabase/server';
import { createClient as createSupabaseClient } from '@supabase/supabase-js';

export const runtime = 'nodejs';

export async function POST(request: Request) {
  // Cookie 기반 또는 Bearer 토큰 기반 인증 모두 지원
  const authHeader = request.headers.get('authorization');
  let user = null;

  if (authHeader?.startsWith('Bearer ')) {
    const token = authHeader.slice(7);
    const client = createSupabaseClient(
      process.env.NEXT_PUBLIC_SUPABASE_URL!,
      process.env.NEXT_PUBLIC_SUPABASE_ANON_KEY!,
    );
    const { data } = await client.auth.getUser(token);
    user = data?.user ?? null;
  } else {
    const supabase = await createClient();
    const { data } = await supabase.auth.getUser();
    user = data?.user ?? null;
  }

  if (!user) return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });

  const body = await request.json();
  const token = (body.token as string | undefined)?.trim();
  if (!token) return NextResponse.json({ error: '견적서 코드를 입력해주세요' }, { status: 400 });

  const admin = createAdminClient();

  const { data: quote, error } = await admin
    .from('quotes')
    .select('id, status, user_id, client_email')
    .eq('public_token', token)
    .single();

  if (error || !quote) {
    return NextResponse.json({ error: '견적서를 찾을 수 없습니다. 코드를 다시 확인해주세요.' }, { status: 404 });
  }
  if (quote.status === 'draft') {
    return NextResponse.json({ error: '아직 발송되지 않은 견적서입니다.' }, { status: 400 });
  }
  if (quote.user_id && quote.user_id !== user.id) {
    return NextResponse.json({ error: '이미 다른 계정에 연결된 견적서입니다.' }, { status: 400 });
  }
  if (quote.user_id === user.id) {
    return NextResponse.json({ success: true, quoteId: quote.id, alreadyLinked: true });
  }

  const { error: updateErr } = await admin
    .from('quotes')
    .update({ user_id: user.id, updated_at: new Date().toISOString() })
    .eq('id', quote.id);

  if (updateErr) return NextResponse.json({ error: updateErr.message }, { status: 500 });

  return NextResponse.json({ success: true, quoteId: quote.id });
}