// Aggressive process cleanup utility
import { exec } from 'child_process'
import { promisify } from 'util'

const execAsync = promisify(exec)

class AggressiveCleanup {
  private static instance: AggressiveCleanup
  private cleanupInterval: NodeJS.Timeout | null = null
  private isRunning = false
  private isInitialized = false

  private constructor() {
    // Don't auto-start - let startup.ts control it
  }

  static getInstance(): AggressiveCleanup {
    if (!AggressiveCleanup.instance) {
      AggressiveCleanup.instance = new AggressiveCleanup()
    }
    return AggressiveCleanup.instance
  }

  startPeriodicCleanup() {
    if (this.isInitialized) {
      console.log('🔄 Aggressive cleanup already initialized')
      return
    }

    this.isInitialized = true
    console.log('🚀 Starting aggressive cleanup system')

    // In development, use on-demand cleanup instead of periodic
    if (process.env.NODE_ENV === 'development') {
      console.log('🔧 Development mode: Using on-demand cleanup (triggered after analysis)')
      console.log('✅ On-demand cleanup system ready')
      return
    }

    // Production: Clean up every 10 minutes (longer intervals)
    this.cleanupInterval = setInterval(async () => {
      try {
        await this.cleanupOrphanedProcesses()
      } catch (error) {
        console.error('Error in periodic cleanup:', error)
      }
    }, 10 * 60 * 1000) // 10 minutes

    // Also run initial cleanup after 60 seconds
    setTimeout(() => {
      this.cleanupOrphanedProcesses().catch(console.error)
    }, 60000)

    console.log('✅ Periodic cleanup system started (10 min intervals)')
  }

  async cleanupOrphanedProcesses(): Promise<void> {
    if (this.isRunning) return
    
    this.isRunning = true
    const isDevelopment = process.env.NODE_ENV === 'development'
    const cleanupType = isDevelopment ? 'gentle' : 'aggressive'
    
    console.log(`🧹 Running ${cleanupType} cleanup for orphaned processes...`)

    try {
      // Check for active analysis sessions
      try {
        const { progressTracker } = await import('./progress-tracker')
        const activeSessions = progressTracker.getActiveSessions()
        
        if (activeSessions.length > 0) {
          console.log(`⚠️  Skipping cleanup - ${activeSessions.length} active analysis sessions: ${activeSessions.join(', ')}`)
          return
        }
        
        console.log('✅ No active analysis sessions, proceeding with cleanup')
      } catch (importError) {
        console.error('❌ Error importing progress tracker:', importError)
        console.log('⚠️  Skipping cleanup due to import error')
        return
      }

      // Find and kill orphaned chromium processes
      const chromiumProcesses = await this.findChromiumProcesses()
      
      if (chromiumProcesses.length > 0) {
        console.log(`Found ${chromiumProcesses.length} chromium processes, cleaning up...`)
        
        for (const pid of chromiumProcesses) {
          try {
            if (isDevelopment) {
              // In development, use gentler SIGTERM first
              console.log(`🔧 Dev mode: Gentle shutdown of process ${pid}`)
              await execAsync(`kill -TERM ${pid}`)
              // Give process 3 seconds to shut down gracefully
              await new Promise(resolve => setTimeout(resolve, 3000))
              
              // Check if process is still running
              try {
                await execAsync(`kill -0 ${pid}`)
                // Process still running, force kill
                console.log(`⚠️  Process ${pid} didn't shut down gracefully, force killing`)
                await execAsync(`kill -9 ${pid}`)
              } catch {
                // Process already dead, that's good
                console.log(`✅ Process ${pid} shut down gracefully`)
              }
            } else {
              // Production: immediate force kill
              await execAsync(`kill -9 ${pid}`)
              console.log(`✅ Killed process ${pid}`)
            }
          } catch (error) {
            // Process might already be dead
            console.log(`ℹ️  Process ${pid} may already be terminated`)
          }
        }
      } else {
        console.log('✅ No orphaned chromium processes found')
      }

      // Clean up temp directories
      try {
        await execAsync('rm -rf /tmp/puppeteer_dev_chrome_profile-* 2>/dev/null || true')
        console.log('✅ Cleaned up temp directories')
      } catch (error) {
        // Ignore errors
      }

      // Clean up shared memory
      try {
        await execAsync('rm -rf /dev/shm/.org.chromium.* 2>/dev/null || true')
        console.log('✅ Cleaned up shared memory')
      } catch (error) {
        // Ignore errors
      }

    } catch (error) {
      console.error(`Error in ${cleanupType} cleanup:`, error)
    } finally {
      this.isRunning = false
    }
  }

  private async findChromiumProcesses(): Promise<string[]> {
    try {
      const { stdout } = await execAsync('ps aux | grep -E "(chromium|chrome)" | grep -v grep | awk \'{print $2}\'')
      return stdout.trim().split('\n').filter((pid: string) => pid && pid !== '')
    } catch (error) {
      return []
    }
  }

  async forceCleanup(): Promise<void> {
    console.log('🚨 Force cleanup initiated...')
    
    // Stop periodic cleanup
    if (this.cleanupInterval) {
      clearInterval(this.cleanupInterval)
    }

    // Run aggressive cleanup
    await this.cleanupOrphanedProcesses()
    
    // Kill all chromium processes
    try {
      await execAsync('pkill -9 -f "chromium" 2>/dev/null || true')
      await execAsync('pkill -9 -f "chrome" 2>/dev/null || true')
      console.log('✅ Force killed all browser processes')
    } catch (error) {
      console.error('Error in force cleanup:', error)
    }
  }

  // New method for on-demand cleanup after analysis
  async runPostAnalysisCleanup(): Promise<void> {
    console.log('🧹 Post-analysis cleanup triggered...')
    
    // Small delay to ensure analysis processes are fully closed
    await new Promise(resolve => setTimeout(resolve, 2000))
    
    await this.cleanupOrphanedProcesses()
  }

  stop(): void {
    if (this.cleanupInterval) {
      clearInterval(this.cleanupInterval)
      this.cleanupInterval = null
    }
  }
}

// Initialize the aggressive cleanup
const aggressiveCleanup = AggressiveCleanup.getInstance()

export default aggressiveCleanup