import { NextRequest, NextResponse } from "next/server";
import { prisma } from "@/lib/prisma";

/**
 * app/api/webhooks/mail/route.ts
 * 
 * Webhook endpoint for incoming mail notifications.
 * Uses Prisma to look up user mappings in the database.
 */

export async function POST(req: NextRequest) {
  let aliciMail = "Bilinmiyor";
  let sender = "Bilinmiyor";
  let subject = "(Konu Yok)";

  try {
    const data = await req.json();
    console.log("[Mail Webhook] Gelen Payload:", JSON.stringify(data));
    
    // Extract basic info from the incoming payload (Mailcow handles these fields)
    aliciMail = (data.to || data.rcpt || "").toLowerCase().trim();
    sender = data.from || "Bilinmiyor";
    subject = data.subject || "(Konu Yok)";
    
    console.log(`[Mail Webhook] İşleniyor: ${sender} -> ${aliciMail}`);

    // 1. Find mapping in database
    const mapping = await prisma.mailboxMapping.findUnique({
      where: { email: aliciMail },
      include: { user: true },
    });

    if (mapping?.user) {
      const { user } = mapping;
      const targetChatId = user.telegramId;

      if (targetChatId && process.env.TELEGRAM_BOT_TOKEN) {
        const message = `🔔 *Yeni Mail Geldi!*\n\n📧 *Alıcı:* ${aliciMail}\n👤 *Gönderen:* ${sender}\n📝 *Konu:* ${subject}`;
        const telegramUrl = `https://api.telegram.org/bot${process.env.TELEGRAM_BOT_TOKEN}/sendMessage`;
        
        let status = "SENT";
        let errorDetail = null;

        try {
          const res = await fetch(telegramUrl, {
            method: "POST",
            headers: { "Content-Type": "application/json" },
            body: JSON.stringify({
              chat_id: targetChatId,
              text: message,
              parse_mode: "Markdown",
            }),
          });

          if (!res.ok) {
            status = "FAILED";
            errorDetail = `Telegram API Error: ${res.status} ${await res.text()}`;
          }
        } catch (err: any) {
          status = "FAILED";
          errorDetail = `Network Error: ${err.message}`;
        }

        // Log successful/failed delivery
        await prisma.notificationLog.create({
          data: {
            mailbox: aliciMail,
            sender,
            subject,
            status,
            error: errorDetail,
            userId: user.id,
          },
        });
      } else {
        // Log that user was found but notification skipped
        await prisma.notificationLog.create({
          data: {
            mailbox: aliciMail,
            sender,
            subject,
            status: "FAILED",
            error: !process.env.TELEGRAM_BOT_TOKEN ? "Bot token missing" : "User has no Telegram ID",
            userId: user.id,
          },
        });
      }
    } else {
      console.log(`[Webhook] Sahibi bilinmeyen veya eşleşmeyen mail: ${aliciMail}`);
      
      // Log unmapped mail
      await prisma.notificationLog.create({
        data: {
          mailbox: aliciMail,
          sender,
          subject,
          status: "FAILED",
          error: "No user mapping found for this email",
        },
      });
    }

    return NextResponse.json({ status: "ok" });
  } catch (error: any) {
    console.error(`[Mail Webhook] Hata: ${error.message}`);
    
    // Attempt to log the fatal error if we have enough info
    try {
      await prisma.notificationLog.create({
        data: {
          mailbox: aliciMail,
          sender,
          subject,
          status: "FAILED",
          error: `Fatal Error: ${error.message}`,
        },
      });
    } catch (dbErr) {
      console.error("[Mail Webhook] Could not even log the error to DB");
    }

    return NextResponse.json({ error: "İşlem başarısız" }, { status: 500 });
  }
}