/*
 * NOTE: This endpoint is now mostly for backward compatibility.
 * The main email list API (/api/courrier) now fetches full email content,
 * so individual email fetching is typically not needed.
 * This is kept for cases where individual email access is still required
 * or when using older client code.
 */

import { NextResponse } from 'next/server';
import { getServerSession } from 'next-auth';
import { authOptions } from '@/app/api/auth/[...nextauth]/route';
import { getEmailContent, markEmailReadStatus } from '@/lib/services/email-service';
import { getCachedEmailContent, invalidateEmailContentCache } from '@/lib/redis';

export async function GET(
  request: Request,
  context: { params: { id: string } }
) {
  try {
    const session = await getServerSession(authOptions);
    if (!session || !session.user?.id) {
      return NextResponse.json(
        { error: "Not authenticated" },
        { status: 401 }
      );
    }

    // Await params as per Next.js requirements
    const params = await context.params;
    const id = params?.id;
    if (!id) {
      return NextResponse.json(
        { error: "Missing email ID" },
        { status: 400 }
      );
    }

    const { searchParams } = new URL(request.url);
    const folder = searchParams.get("folder") || "INBOX";
    const accountId = searchParams.get("accountId");

    try {
      // Try to get email from Redis cache first
      const cachedEmail = await getCachedEmailContent(session.user.id, accountId || 'default', id);
      if (cachedEmail) {
        console.log(`Using cached email content for ${session.user.id}:${id}`);
        return NextResponse.json(cachedEmail);
      }
      
      console.log(`Cache miss for email content ${session.user.id}:${id}, fetching from IMAP`);
      
      // Use the email service to fetch the email content
      const email = await getEmailContent(session.user.id, id, folder, accountId || undefined);
      
      // Return the complete email object
      return NextResponse.json(email);
    } catch (error: any) {
      console.error("Error fetching email content:", error);
      return NextResponse.json(
        { error: "Failed to fetch email content", message: error.message },
        { status: 500 }
      );
    }
  } catch (error: any) {
    console.error("Error in GET:", error);
    return NextResponse.json(
      { error: "Internal server error", message: error.message },
      { status: 500 }
    );
  }
}

// Add a route to mark email as read
export async function POST(
  request: Request,
  context: { params: { id: string } }
) {
  try {
    const session = await getServerSession(authOptions);
    if (!session || !session.user?.id) {
      return NextResponse.json(
        { error: "Not authenticated" },
        { status: 401 }
      );
    }

    // Await params as per Next.js requirements
    const params = await context.params;
    const id = params?.id;
    if (!id) {
      return NextResponse.json(
        { error: "Missing email ID" },
        { status: 400 }
      );
    }

    const { action } = await request.json();
    
    if (action !== 'mark-read' && action !== 'mark-unread') {
      return NextResponse.json(
        { error: "Invalid action. Supported actions: mark-read, mark-unread" },
        { status: 400 }
      );
    }

    const { searchParams } = new URL(request.url);
    const folder = searchParams.get("folder") || "INBOX";
    const accountId = searchParams.get("accountId");

    // Use the email service to mark the email
    const success = await markEmailReadStatus(
      session.user.id,
      id,
      action === 'mark-read',
      folder
    );

    if (!success) {
      return NextResponse.json(
        { error: `Failed to ${action === 'mark-read' ? 'mark email as read' : 'mark email as unread'}` },
        { status: 500 }
      );
    }

    // Invalidate cache for this email
    await invalidateEmailContentCache(session.user.id, accountId || 'default', id);
    
    return NextResponse.json({ success: true });
  } catch (error: any) {
    console.error("Error in POST:", error);
    return NextResponse.json(
      { error: "Internal server error", message: error.message },
      { status: 500 }
    );
  }
}