import { NextResponse } from 'next/server';
import { getServerSession } from 'next-auth';
import { authOptions } from '@/lib/auth';
import { markEmailReadStatus } from '@/lib/services/email-service';

// Global cache reference (will be moved to a proper cache solution in the future)
declare global {
  var emailListCache: { [key: string]: { data: any, timestamp: number } };
}

// Helper function to invalidate cache for a specific folder
const invalidateCache = (userId: string, folder?: string) => {
  if (!global.emailListCache) return;
  
  Object.keys(global.emailListCache).forEach(key => {
    // If folder is provided, only invalidate that folder's cache
    if (folder) {
      if (key.includes(`${userId}:${folder}`)) {
        delete global.emailListCache[key];
      }
    } else {
      // Otherwise invalidate all user's caches
      if (key.startsWith(`${userId}:`)) {
        delete global.emailListCache[key];
      }
    }
  });
};

// Mark email as read
export async function POST(
  request: Request,
  { params }: { params: { id: string } }
) {
  try {
    const session = await getServerSession(authOptions);
    if (!session?.user?.id) {
      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 });
    }

    const { id: emailId } = params;
    if (!emailId) {
      return NextResponse.json({ error: 'Email ID is required' }, { status: 400 });
    }

    const { folder = 'INBOX', accountId, isRead = true } = await request.json();

    // Extract account ID from folder name if present and none was explicitly provided
    const folderAccountId = folder.includes(':') ? folder.split(':')[0] : accountId;
    
    // Use the most specific account ID available
    const effectiveAccountId = folderAccountId || accountId || 'default';
    
    // Normalize folder name by removing account prefix if present
    const normalizedFolder = folder.includes(':') ? folder.split(':')[1] : folder;

    // Log operation details for debugging
    console.log(`Marking email ${emailId} as ${isRead ? 'read' : 'unread'} in folder ${normalizedFolder} for account ${effectiveAccountId}`);

    const success = await markEmailReadStatus(
      session.user.id,
      emailId,
      isRead,
      normalizedFolder,
      effectiveAccountId
    );

    if (!success) {
      return NextResponse.json(
        { error: 'Failed to mark email as read' },
        { status: 500 }
      );
    }

    return NextResponse.json({ success: true });
  } catch (error) {
    console.error('Error marking email as read:', error);
    return NextResponse.json(
      { error: 'Internal server error' },
      { status: 500 }
    );
  }
}