import { exec, spawn, net, promisify, EventEmitter, execAsync } from './plugins.js';

export interface ClamAVLogEvent {
  timestamp: string;
  message: string;
  type: 'update' | 'scan' | 'system' | 'error';
}

export class ClamAVManager extends EventEmitter {
  private containerId: string | null = null;
  private containerName = 'clamav-daemon';
  private imageTag = 'clamav/clamav:latest';
  private port = 3310;
  private logs: ClamAVLogEvent[] = [];

  constructor() {
    super();
  }

  public getLogs(): ClamAVLogEvent[] {
    return this.logs;
  }

  /**
   * Start the ClamAV container if it's not already running
   */
  public async startContainer(): Promise<void> {
    try {
      console.log('[ClamAV] Starting container initialization...');
      
      // Check if container is already running
      const { stdout: psOutput } = await execAsync('docker ps --filter name=' + this.containerName);
      if (psOutput.includes(this.containerName)) {
        console.log('[ClamAV] Container is already running');
        this.containerId = (await execAsync(`docker ps -q --filter name=${this.containerName}`)).stdout.trim();
        console.log('[ClamAV] Container ID:', this.containerId);
        this.attachLogWatcher();
        await this.waitForInitialization();
        return;
      }

      // Check if container exists but is stopped
      const { stdout: psaOutput } = await execAsync('docker ps -a --filter name=' + this.containerName);
      if (psaOutput.includes(this.containerName)) {
        console.log('[ClamAV] Found stopped container, starting it...');
        await execAsync(`docker start ${this.containerName}`);
        this.containerId = (await execAsync(`docker ps -q --filter name=${this.containerName}`)).stdout.trim();
        console.log('[ClamAV] Started existing container, ID:', this.containerId);
      } else {
        // Create and start new container
        console.log('[ClamAV] Creating new container...');
        const { stdout } = await execAsync(
          `docker run -d --name ${this.containerName} -p ${this.port}:3310 ${this.imageTag}`
        );
        this.containerId = stdout.trim();
        console.log('[ClamAV] Created new container, ID:', this.containerId);
      }

      this.attachLogWatcher();
      console.log('[ClamAV] Waiting for initialization...');
      await this.waitForInitialization();
      console.log('[ClamAV] Container successfully initialized');
    } catch (error) {
      console.error('[ClamAV] Error starting container:', error);
      throw error;
    }
  }

  /**
   * Stop the ClamAV container
   */
  public async stopContainer(): Promise<void> {
    if (!this.containerId) {
      console.log('No ClamAV container is running');
      return;
    }

    try {
      await execAsync(`docker stop ${this.containerId}`);
      console.log('Stopped ClamAV container');
    } catch (error) {
      console.error('Error stopping ClamAV container:', error);
      throw error;
    }
  }

  /**
   * Manually trigger a database update
   */
  public async updateDatabase(): Promise<void> {
    if (!this.containerId) {
      throw new Error('ClamAV container is not running');
    }

    try {
      // First check if freshclam is already running
      const { stdout: psOutput } = await execAsync(`docker exec ${this.containerId} ps aux | grep freshclam`);
      if (psOutput.includes('/usr/local/sbin/freshclam -d')) {
        console.log('Freshclam daemon is already running');
        // Wait a bit to ensure database is updated
        await new Promise(resolve => setTimeout(resolve, 2000));
        return;
      }

      // If not running as daemon, try to update manually
      const { stdout, stderr } = await execAsync(`docker exec ${this.containerId} freshclam --no-warnings`);
      console.log('Database update output:', stdout);
      if (stderr) {
        console.error('Database update errors:', stderr);
      }
    } catch (error) {
      // Check if the error is due to freshclam already running
      if (error.stderr?.includes('ERROR: Problem with internal logger') || 
          error.stdout?.includes('Resource temporarily unavailable')) {
        console.log('Freshclam is already running, skipping manual update');
        return;
      }
      console.error('Error updating ClamAV database:', error);
      throw error;
    }
  }

  /**
   * Get the current database version information
   */
  public async getDatabaseInfo(): Promise<string> {
    if (!this.containerId) {
      throw new Error('ClamAV container is not running');
    }

    try {
      // Try both .cld and .cvd files since ClamAV can use either format
      try {
        const { stdout } = await execAsync(`docker exec ${this.containerId} sigtool --info /var/lib/clamav/daily.cld`);
        return stdout;
      } catch {
        const { stdout } = await execAsync(`docker exec ${this.containerId} sigtool --info /var/lib/clamav/daily.cvd`);
        return stdout;
      }
    } catch (error) {
      console.error('Error getting database info:', error);
      throw error;
    }
  }

  /**
   * Watch container logs and emit events for different types of log messages
   */
  private attachLogWatcher(): void {
    if (!this.containerId) return;

    const logProcess = spawn('docker', ['logs', '-f', this.containerId]);

    logProcess.stdout.on('data', (data) => {
      const lines = data.toString().split('\n');
      lines.forEach(line => {
        if (!line.trim()) return;

        const event: ClamAVLogEvent = {
          timestamp: new Date().toISOString(),
          message: line,
          type: this.determineLogType(line)
        };

        this.logs.push(event);
        this.emit('log', event);
        console.log(`[ClamAV ${event.type}] ${event.message}`);
      });
    });

    logProcess.stderr.on('data', (data) => {
      const event: ClamAVLogEvent = {
        timestamp: new Date().toISOString(),
        message: data.toString(),
        type: 'error'
      };

      this.logs.push(event);
      this.emit('log', event);
      console.error(`[ClamAV error] ${event.message}`);
    });

    logProcess.on('error', (error) => {
      console.error('Error in log watcher:', error);
    });
  }

  /**
   * Determine the type of log message
   */
  private determineLogType(logMessage: string): ClamAVLogEvent['type'] {
    const lowerMessage = logMessage.toLowerCase();
    if (lowerMessage.includes('update') || lowerMessage.includes('freshclam')) {
      return 'update';
    } else if (lowerMessage.includes('scan') || lowerMessage.includes('found')) {
      return 'scan';
    } else if (lowerMessage.includes('error') || lowerMessage.includes('warning')) {
      return 'error';
    }
    return 'system';
  }

  /**
   * Wait for ClamAV to initialize by checking both logs and service readiness
   */
  private async waitForInitialization(): Promise<void> {
    return new Promise((resolve, reject) => {
      if (!this.containerId) {
        reject(new Error('Container ID not set'));
        return;
      }

      let timeout: NodeJS.Timeout;
      let checkCount = 0;
      const maxChecks = 60; // Check for 60 seconds
      const startTime = Date.now();

      // Check service readiness
      const checkService = async () => {
        try {
          const elapsedTime = Math.round((Date.now() - startTime) / 1000);
          console.log(`[ClamAV] Checking service readiness (attempt ${checkCount + 1}, ${elapsedTime}s elapsed)...`);

          // First check if the service is accepting connections
          const client = new net.Socket();
          await new Promise<void>((resolveConn, rejectConn) => {
            const connectTimeout = setTimeout(() => {
              client.destroy();
              rejectConn(new Error('Connection timeout'));
            }, 1000);

            client.connect(this.port, 'localhost', () => {
              clearTimeout(connectTimeout);
              client.end();
              resolveConn();
            });
            
            client.on('error', (err) => {
              clearTimeout(connectTimeout);
              rejectConn(err);
            });
          });

          // Verify the service is responding to commands
          const { stdout } = await execAsync(`echo PING | nc localhost ${this.port}`);
          if (!stdout.includes('PONG')) {
            throw new Error('Service not responding to commands');
          }

          // If we can connect and get a PONG, the service is ready
          console.log('[ClamAV] Service is accepting connections and responding to commands');
          cleanup();
          resolve();
        } catch (error) {
          // Service not ready yet, will retry
          if (checkCount >= maxChecks) {
            cleanup();
            reject(new Error(`ClamAV initialization timed out after ${maxChecks} seconds. Last error: ${error.message}`));
            return;
          }
          checkCount++;
        }
      };

      const cleanup = () => {
        clearTimeout(timeout);
        clearInterval(serviceCheck);
      };

      const serviceCheck = setInterval(checkService, 1000);

      timeout = setTimeout(() => {
        cleanup();
        reject(new Error('ClamAV initialization timed out after 60 seconds'));
      }, 60000);

      // Start initial service check
      checkService();
    });
  }
}