import { NextResponse } from 'next/server';
import { prisma } from '@/lib/prisma';
import { sendTelegramNotification } from '@/lib/notifications';
import { sendWA } from '@/lib/whatsapp';

// Bu kısım normalde .env içinde olmalı
const WEBHOOK_SECRET = process.env.WEBHOOK_SIGNAL_SECRET || 'besiktasK1903*';

// RFC 2047 Decode Fonksiyonu
function decodeMimeText(text: string) {
  if (!text) return text;
  
  // Eğer metin =? ile başlıyorsa decode etmeye çalış
  return text.replace(/=\?([^?]+)\?([QB])\?([^?]+)\?=/gi, (match, charset, encoding, data) => {
    try {
      if (encoding.toUpperCase() === 'Q') {
        // Quoted-Printable decode
        return data
          .replace(/_/g, ' ')
          .replace(/=([0-9A-F]{2})/gi, (_: any, hex: string) => String.fromCharCode(parseInt(hex, 16)));
      } else if (encoding.toUpperCase() === 'B') {
        // Base64 decode
        return Buffer.from(data, 'base64').toString(charset.toLowerCase() === 'utf-8' ? 'utf8' : 'binary');
      }
    } catch (e) {
      return match;
    }
    return match;
  });
}

export async function POST(request: Request) {
  const secret = request.headers.get('x-ayristech-secret');

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

  const body = await request.json();
  const { to, event, subject: incomingSubject, snippet: incomingSnippet, from: incomingFrom } = body;

  const subject = decodeMimeText(incomingSubject || "");
  console.log(`📩 Webhook Sinyali Alındı! Alıcı: ${to} | Konu: ${subject}`);

  try {
    // 1. Mailbox Mapping kontrolü
    const mapping = await prisma.mailboxMapping.findUnique({
      where: { email: to },
      include: { user: true }
    });

    if (!mapping) {
      console.log(`[Signal] Mapping bulunamadı: ${to}`);
      return NextResponse.json({ success: true, message: 'No mapping found' });
    }

    // 2. Mail İçeriğini Belirle
    if (!incomingSubject && !incomingSnippet) {
      console.log(`[Signal] İçerik eksik, işlem durduruldu: ${to}`);
      return NextResponse.json({ success: true, message: 'No content provided' });
    }

    const mailData = {
      subject: subject || "(Konu Yok)",
      text: incomingSnippet || "",
      from: incomingFrom || "Bilinmiyor"
    };

    // 3. Bildirim Gönder (Telegram)
    const notificationResult = await sendTelegramNotification(
      mapping.userId,
      to,
      mailData.from,
      mailData.subject,
      "" // Analiz bilgisini kaldırdık
    );

    // 4. Bildirim Gönder (WhatsApp)
    // Şu an için varsayılan numaraya gönderiyoruz, ilerde User modeline alan eklenebilir.
    const waNumber = process.env.DEFAULT_WHATSAPP_NUMBER || '905543765103';
    const waMessage = `📩 *Yeni E-posta*\n\n*Gönderen:* ${mailData.from}\n*Konu:* ${mailData.subject}\n*Alıcı:* ${to}\n\n_AyrisMail Central_`;
    
    await sendWA(waNumber, waMessage);

    // 5. Bildirim Logu
    await prisma.notificationLog.create({
      data: {
        mailbox: to,
        sender: mailData.from,
        subject: mailData.subject,
        status: notificationResult.status,
        userId: mapping.userId,
        error: notificationResult.error
      }
    });

    return NextResponse.json({ 
      success: true, 
      notification: notificationResult.status,
      subject: mailData.subject
    });

  } catch (error: any) {
    console.error("[Signal Webhook] Hata:", error.message);
    return NextResponse.json({ error: error.message }, { status: 500 });
  }
}