import { NextResponse } from 'next/server';
import { createCallRecord, getAgentSettings, getUser } from '@/lib/firestore';

const VAPI_BASE_URL = 'https://api.vapi.ai';
const vapiPrivateKey = process.env.VAPI_PRIVATE_KEY;

export async function POST(request: Request) {
  try {
    if (!vapiPrivateKey) {
      return NextResponse.json({ error: 'Vapi not configured.' }, { status: 500 });
    }

    const body = await request.json();
    const phoneNumber = body?.phoneNumber as string | undefined;
    const scheduledTaskId = body?.scheduledTaskId as string | undefined;

    if (!phoneNumber) {
      return NextResponse.json({ error: 'Phone number is required.' }, { status: 400 });
    }

    // TODO: Get userId from auth token
    const userId = body?.userId ?? 'test-user-id';
    const user = await getUser(userId);
    if (!user || user.creditBalance < 1) {
      return NextResponse.json({ error: 'Insufficient credits.' }, { status: 400 });
    }

    const agentSettings = await getAgentSettings(userId);

    const assistantPayload = {
      name: agentSettings?.agentName ?? 'HolaCompi',
      instructions:
        agentSettings?.agentInstructions ??
        'You are HolaCompi, a helpful Spanish friend who makes phone calls on behalf of users.',
      model: 'gpt-4o-mini',
      voice: {
        provider: 'openai',
        voice: 'alloy',
      },
      language: agentSettings?.primaryCallLanguage ?? 'English',
    };

    // Create assistant dynamically based on agent settings
    const assistantResponse = await fetch(`${VAPI_BASE_URL}/assistant`, {
      method: 'POST',
      headers: {
        Authorization: `Bearer ${vapiPrivateKey}`,
        'Content-Type': 'application/json',
      },
      body: JSON.stringify(assistantPayload),
    });

    if (!assistantResponse.ok) {
      const errorText = await assistantResponse.text();
      return NextResponse.json({ error: errorText }, { status: 500 });
    }

    const assistant = await assistantResponse.json();

    // Initiate outbound call via Vapi API
    const callResponse = await fetch(`${VAPI_BASE_URL}/call`, {
      method: 'POST',
      headers: {
        Authorization: `Bearer ${vapiPrivateKey}`,
        'Content-Type': 'application/json',
      },
      body: JSON.stringify({
        assistantId: assistant.id,
        phoneNumber,
        // TODO: Adjust payload based on Vapi call schema (customer/from numbers)
      }),
    });

    if (!callResponse.ok) {
      const errorText = await callResponse.text();
      return NextResponse.json({ error: errorText }, { status: 500 });
    }

    const callData = await callResponse.json();

    await createCallRecord({
      userId,
      phoneNumber,
      status: 'initiated',
      vapiCallId: callData.id,
      assistantId: assistant.id,
      scheduledTaskId,
    });

    return NextResponse.json({ status: callData.status ?? 'initiated', callId: callData.id });
  } catch (error) {
    console.error('Vapi create call error:', error);
    return NextResponse.json({ error: 'Failed to create call.' }, { status: 500 });
  }
}