import { NextResponse } from 'next/server';
import { Timestamp } from 'firebase/firestore';
import { getCallByVapiCallId, getUser, updateCallRecord, updateUserCredits } from '@/lib/firestore';

export async function POST(request: Request) {
  try {
    const payload = await request.json();
    const eventType = payload?.event || payload?.type;
    const callPayload = payload?.call || payload?.data?.call || payload;
    const vapiCallId = callPayload?.id as string | undefined;

    if (!vapiCallId) {
      return NextResponse.json({ error: 'Missing call id.' }, { status: 400 });
    }

    const callRecord = await getCallByVapiCallId(vapiCallId);
    if (!callRecord) {
      return NextResponse.json({ error: 'Call record not found.' }, { status: 404 });
    }

    if (eventType === 'call-started' || eventType === 'call.started') {
      await updateCallRecord(callRecord.id, {
        status: 'started',
        startedAt: Timestamp.now(),
      });
    }

    if (eventType === 'call-failed' || eventType === 'call.failed') {
      await updateCallRecord(callRecord.id, {
        status: 'failed',
        endedAt: Timestamp.now(),
      });
    }

    if (eventType === 'call-ended' || eventType === 'call.ended') {
      const durationSeconds =
        Number(callPayload?.durationSeconds) ||
        Number(callPayload?.duration) ||
        0;
      const creditsUsed = Math.ceil(durationSeconds / 60);

      await updateCallRecord(callRecord.id, {
        status: 'ended',
        endedAt: Timestamp.now(),
        durationSeconds,
        creditsUsed,
        recordingUrl: callPayload?.recordingUrl || callPayload?.recording?.url,
        transcript: callPayload?.transcript || callPayload?.summary,
      });

      const user = await getUser(callRecord.userId);
      if (user) {
        const newBalance = Math.max(0, user.creditBalance - creditsUsed);
        await updateUserCredits(callRecord.userId, newBalance);
      }
    }

    return NextResponse.json({ received: true });
  } catch (error) {
    console.error('Vapi webhook error:', error);
    return NextResponse.json({ error: 'Webhook processing failed.' }, { status: 500 });
  }
}