import { NextResponse } from 'next/server';
import { getServerSession } from 'next-auth';
import { authOptions } from '@/app/api/auth/[...nextauth]/route';
import { getMailboxes } from '@/lib/services/email-service';
import { ImapFlow } from 'imapflow';
import { prisma } from '@/lib/prisma';
import { getCachedEmailCredentials } from '@/lib/redis';

export async function GET(request: Request) {
  // Verify auth
  const session = await getServerSession(authOptions);
  if (!session?.user?.id) {
    return NextResponse.json(
      { error: 'Unauthorized' },
      { status: 401 }
    );
  }
  
  const { searchParams } = new URL(request.url);
  const accountId = searchParams.get('accountId');
  const userId = session.user.id;
  
  try {
    // If specific accountId is provided, get folders for that account
    if (accountId) {
      // Get account from database
      const account = await prisma.mailCredentials.findFirst({
        where: { 
          id: accountId,
          userId 
        },
        select: {
          email: true,
          password: true,
          host: true,
          port: true
        }
      });
      
      if (!account) {
        return NextResponse.json(
          { error: 'Account not found' },
          { status: 404 }
        );
      }
      
      // Connect to IMAP server for this account
      const client = new ImapFlow({
        host: account.host,
        port: account.port,
        secure: true,
        auth: {
          user: account.email,
          pass: account.password,
        },
        logger: false,
        tls: {
          rejectUnauthorized: false
        }
      });
      
      try {
        await client.connect();
        
        // Get folders for this account
        const folders = await getMailboxes(client);
        
        // Close connection
        await client.logout();
        
        return NextResponse.json({
          accountId,
          email: account.email,
          folders
        });
      } catch (error) {
        return NextResponse.json(
          { 
            error: 'Failed to connect to IMAP server',
            details: error instanceof Error ? error.message : 'Unknown error' 
          },
          { status: 500 }
        );
      }
    } else {
      // Get all accounts for this user
      const accounts = await prisma.mailCredentials.findMany({
        where: { userId },
        select: {
          id: true,
          email: true,
          password: true,
          host: true,
          port: true
        }
      });
      
      if (accounts.length === 0) {
        return NextResponse.json({
          accounts: []
        });
      }
      
      // Fetch folders for each account individually
      const accountsWithFolders = await Promise.all(accounts.map(async (account) => {
        try {
          // Connect to IMAP server for this specific account
          const client = new ImapFlow({
            host: account.host,
            port: account.port,
            secure: true,
            auth: {
              user: account.email,
              pass: account.password,
            },
            logger: false,
            tls: {
              rejectUnauthorized: false
            }
          });
          
          await client.connect();
          
          // Get folders for this account
          const folders = await getMailboxes(client);
          
          // Close connection
          await client.logout();
          
          // Add display_name and color from database
          const metadata = await prisma.$queryRaw`
            SELECT display_name, color 
            FROM "MailCredentials" 
            WHERE id = ${account.id}
          `;
          
          const displayMetadata = Array.isArray(metadata) && metadata.length > 0 ? metadata[0] : {};
          
          return {
            id: account.id,
            email: account.email,
            display_name: displayMetadata.display_name || account.email,
            color: displayMetadata.color || "#0082c9",
            folders
          };
        } catch (error) {
          console.error(`Error fetching folders for account ${account.email}:`, error);
          // Return fallback folders on error
          return {
            id: account.id,
            email: account.email,
            folders: ['INBOX', 'Sent', 'Drafts', 'Trash'] // Fallback folders on error
          };
        }
      }));
      
      return NextResponse.json({
        accounts: accountsWithFolders
      });
    }
  } catch (error) {
    return NextResponse.json(
      { 
        error: 'Failed to get account folders',
        details: error instanceof Error ? error.message : 'Unknown error' 
      },
      { status: 500 }
    );
  }
}