import { NextRequest, NextResponse } from 'next/server';
import { withAuth } from '@/lib/api-guards';
import { setupLogRedaction } from '@/lib/log-redactor';

setupLogRedaction();

export const POST = withAuth(async (req, { session, prisma }) => {
  try {
    const body = await req.json();
    const { period, simulateOnly } = body;

    if (!period || !/^\d{4}-\d{2}$/.test(period)) {
      return NextResponse.json(
        { error: 'El período es obligatorio y debe tener formato YYYY-MM.' },
        { status: 400 }
      );
    }

    const isDev = process.env.IS_E2E_TEST === 'true' || process.env.NODE_ENV === 'development';
    const signature = isDev
      ? (process.env.N8N_WEBHOOK_SECRET_DEV || 'qUHuPqPjA65psdtwQU7zgp/DVkvd1xXk2WP/vzbnEdc=')
      : (process.env.N8N_WEBHOOK_SECRET || 'Ecjb2s33tHJppNBDJ/DxXEjHWKow8bNWmsQrk1sQKyQ=');

    // Local bypass for E2E tests to prevent cloud n8n routing back to localhost
    if (process.env.IS_E2E_TEST === 'true') {
      console.log('E2E Test Mode: Running calculation locally via n8n endpoints...');
      const localPort = process.env.PORT || '3015';
      const localBase = `http://localhost:${localPort}`;

      // 1. Fetch calculation data locally
      const fetchRes = await fetch(`${localBase}/api/n8n/fetch-calculation-data?period=${period}`, {
        headers: { 'x-n8n-signature': signature }
      });
      if (!fetchRes.ok) {
        throw new Error(`Fetch calculation data failed: ${await fetchRes.text()}`);
      }
      const data = await fetchRes.json();

      // 2. Process formula locally
      const processRes = await fetch(`${localBase}/api/n8n/process-formula`, {
        method: 'POST',
        headers: {
          'Content-Type': 'application/json',
          'x-n8n-signature': signature
        },
        body: JSON.stringify({
          period,
          simulateOnly,
          ...data
        })
      });
      if (!processRes.ok) {
        throw new Error(`Process formula failed: ${await processRes.text()}`);
      }
      const processData = await processRes.json();

      // 3. Save settlements locally (if not simulated)
      if (!simulateOnly) {
        const saveRes = await fetch(`${localBase}/api/n8n/save-settlements`, {
          method: 'POST',
          headers: {
            'Content-Type': 'application/json',
            'x-n8n-signature': signature
          },
          body: JSON.stringify({
            period,
            simulateOnly: false,
            results: processData.results,
            uploaderId: session.userId
          })
        });
        if (!saveRes.ok) {
          throw new Error(`Save settlements failed: ${await saveRes.text()}`);
        }
      }

      return NextResponse.json({
        success: true,
        code: 'SETTLEMENTS_CALCULATED',
        metadata: processData.metadata,
        simulated: processData.results
      }, { status: 201 });
    }

    // Determine target n8n webhook URL for dev/prod environment
    const webhookBase = process.env.N8N_API_URL || 'https://n8n.gaboggamer.online';
    const webhookPath = isDev ? 'webhook-test/calculate-settlements' : 'webhook/calculate-settlements';
    const webhookUrl = `${webhookBase}/${webhookPath}`;

    console.log(`Triggering n8n settlement calculation webhook at ${webhookUrl}...`);

    const n8nRes = await fetch(webhookUrl, {
      method: 'POST',
      headers: {
        'Content-Type': 'application/json',
        'x-n8n-signature': signature
      },
      body: JSON.stringify({
        period,
        simulateOnly,
        uploaderId: session.userId
      })
    });

    if (!n8nRes.ok) {
      const errText = await n8nRes.text();
      console.error(`n8n webhook calculation failed with status ${n8nRes.status}:`, errText);
      return NextResponse.json(
        { error: `Error del motor de cálculo externo (n8n): ${n8nRes.status}` },
        { status: 502 }
      );
    }

    const n8nData = await n8nRes.json();
    return NextResponse.json(n8nData, { status: 201 });

  } catch (err: any) {
    console.error('Settlement calculation trigger error:', err);
    return NextResponse.json(
      { error: err.message || 'Error al calcular las liquidaciones.' },
      { status: 500 }
    );
  }
}, ['admin', 'analyst']);