import { NextResponse } from 'next/server';
import { getServerSession } from 'next-auth';
import { authOptions } from "@/app/api/auth/options";
import { getCachedEmailCredentials, getCachedImapSession } from '@/lib/redis';
import { prisma } from '@/lib/prisma';
import { getMailboxes } from '@/lib/services/email-service';
import { ImapFlow } from 'imapflow';

export async function GET() {
  // Verify auth
  const session = await getServerSession(authOptions);
  if (!session?.user?.id) {
    return NextResponse.json(
      { error: 'Unauthorized' },
      { status: 401 }
    );
  }
  
  const userId = session.user.id;
  const debugData: any = {
    userId,
    timestamp: new Date().toISOString(),
    redis: {
      emailCredentials: null,
      session: null
    },
    database: {
      accounts: [],
      schema: null
    },
    imap: {
      connectionAttempt: false,
      connected: false,
      folders: []
    }
  };
  
  // Check Redis cache for credentials
  try {
    const credentials = await getCachedEmailCredentials(userId, 'default');
    if (credentials) {
      debugData.redis.emailCredentials = {
        found: true,
        email: credentials.email,
        host: credentials.host,
        port: credentials.port,
        hasPassword: !!credentials.password,
        hasSmtp: !!credentials.smtp_host
      };
    } else {
      debugData.redis.emailCredentials = { found: false };
    }
  } catch (e) {
    debugData.redis.emailCredentials = { 
      error: e instanceof Error ? e.message : 'Unknown error'
    };
  }
  
  // Check Redis for session data (which contains folders)
  try {
    const sessionData = await getCachedImapSession(userId);
    if (sessionData) {
      debugData.redis.session = {
        found: true,
        lastActive: new Date(sessionData.lastActive).toISOString(),
        hasFolders: !!sessionData.mailboxes,
        folderCount: sessionData.mailboxes?.length || 0,
        folders: sessionData.mailboxes || []
      };
    } else {
      debugData.redis.session = { found: false };
    }
  } catch (e) {
    debugData.redis.session = { 
      error: e instanceof Error ? e.message : 'Unknown error'
    };
  }
  
  // Try to get database schema information to help diagnose issues
  try {
    const schemaInfo = await prisma.$queryRaw`
      SELECT column_name, data_type, is_nullable 
      FROM information_schema.columns
      WHERE table_name = 'MailCredentials'
      AND table_schema = 'public'
      ORDER BY ordinal_position
    `;
    debugData.database.schema = schemaInfo;
  } catch (e) {
    debugData.database.schemaError = e instanceof Error ? e.message : 'Unknown error';
  }
  
  // Check database for accounts
  try {
    const accounts = await prisma.mailCredentials.findMany({
      where: { userId },
      select: {
        id: true,
        email: true,
        host: true,
        port: true
      }
    });
    
    // Also try to get additional fields from raw query
    const accountsWithMetadata = await Promise.all(accounts.map(async (account) => {
      try {
        const rawAccount = await prisma.$queryRaw`
          SELECT display_name, color, smtp_host, smtp_port, smtp_secure, secure
          FROM "MailCredentials" 
          WHERE id = ${account.id}
        `;
        
        const metadata = Array.isArray(rawAccount) && rawAccount.length > 0 
          ? rawAccount[0] 
          : {};
          
        return {
          ...account,
          display_name: metadata.display_name,
          color: metadata.color,
          smtp_host: metadata.smtp_host,
          smtp_port: metadata.smtp_port,
          smtp_secure: metadata.smtp_secure,
          secure: metadata.secure
        };
      } catch (e) {
        return {
          ...account,
          _queryError: e instanceof Error ? e.message : 'Unknown error'
        };
      }
    }));
    
    debugData.database.accounts = accountsWithMetadata;
    debugData.database.accountCount = accounts.length;
  } catch (e) {
    debugData.database.error = e instanceof Error ? e.message : 'Unknown error';
  }
  
  // Try to get IMAP folders for the main account
  if (debugData.redis.emailCredentials?.found || debugData.database.accountCount > 0) {
    try {
      debugData.imap.connectionAttempt = true;
      
      // Use cached credentials
      const credentials = await getCachedEmailCredentials(userId, 'default');
      
      if (credentials && credentials.email && credentials.password) {
        const client = new ImapFlow({
          host: credentials.host,
          port: credentials.port,
          secure: true,
          auth: {
            user: credentials.email,
            pass: credentials.password,
          },
          logger: false,
          tls: {
            rejectUnauthorized: false
          }
        });
        
        await client.connect();
        debugData.imap.connected = true;
        
        // Get folders
        const folders = await getMailboxes(client);
        debugData.imap.folders = folders;
        
        // Close connection
        await client.logout();
      } else {
        debugData.imap.error = "No valid credentials found";
      }
    } catch (e) {
      debugData.imap.error = e instanceof Error ? e.message : 'Unknown error';
    }
  }
  
  return NextResponse.json(debugData);
}