import { NextResponse } from 'next/server';
import { collection, getDocs, getFirestore, query, where, Timestamp } from 'firebase/firestore';
import { app } from '@/lib/firebase';

export async function GET(request: Request) {
  // TODO: Secure this route using a secret header for Vercel Cron.
  const db = getFirestore(app);
  const now = Timestamp.now();

  // TODO: Add index for scheduledAt + status.
  const tasksQuery = query(
    collection(db, 'callTasks'),
    where('status', '==', 'pending'),
    where('scheduledAt', '<=', now)
  );

  const snapshot = await getDocs(tasksQuery);
  const origin = request.headers.get('origin') ?? 'http://localhost:3000';

  for (const docSnap of snapshot.docs) {
    const task = docSnap.data() as any;

    // Trigger the call (TODO: include auth)
    await fetch(`${origin}/api/vapi/create-call`, {
      method: 'POST',
      headers: { 'Content-Type': 'application/json' },
      body: JSON.stringify({
        phoneNumber: task.phoneNumber,
        userId: task.userId,
        scheduledTaskId: docSnap.id,
      }),
    });
  }

  return NextResponse.json({ processed: snapshot.size });
}