package main

import (
	"crypto/rand"
	"encoding/hex"
	"flag"
	"fmt"
	"log"
	"os"
	"os/signal"
	"strings"
	"syscall"
	"time"

	"jiggablend/internal/logger"
	"jiggablend/internal/runner"
)

// Removed SecretsFile - runners now generate ephemeral instance IDs

func main() {
	log.Printf("Runner starting up...")

	// Create client early so we can clean it up on panic
	var client *runner.Client

	defer func() {
		if r := recover(); r != nil {
			log.Printf("Runner panicked: %v", r)
			// Clean up workspace even on panic
			if client != nil {
				client.CleanupWorkspace()
			}
			os.Exit(1)
		}
	}()

	var (
		managerURL    = flag.String("manager", getEnv("MANAGER_URL", "http://localhost:8080"), "Manager URL")
		name          = flag.String("name", getEnv("RUNNER_NAME", ""), "Runner name")
		hostname      = flag.String("hostname", getEnv("RUNNER_HOSTNAME", ""), "Runner hostname")
		apiKeyFlag   = flag.String("api-key", getEnv("API_KEY", ""), "API key for authentication")
		logDir        = flag.String("log-dir", getEnv("LOG_DIR", "./logs"), "Log directory")
		logMaxSize    = flag.Int("log-max-size", getEnvInt("LOG_MAX_SIZE", 100), "Maximum log file size in MB before rotation")
		logMaxBackups = flag.Int("log-max-backups", getEnvInt("LOG_MAX_BACKUPS", 5), "Maximum number of rotated log files to keep")
		logMaxAge     = flag.Int("log-max-age", getEnvInt("LOG_MAX_AGE", 30), "Maximum age in days for rotated log files")
	)
	flag.Parse()
	log.Printf("Flags parsed, hostname: %s", *hostname)

	if *hostname == "" {
		*hostname, _ = os.Hostname()
	}

	// Always generate a random runner ID suffix on startup
	// This ensures every runner has a unique local identifier
	runnerIDStr := generateShortID()
	log.Printf("Generated runner ID suffix: %s", runnerIDStr)

	// Generate runner name with ID if not provided
	if *name == "" {
		*name = fmt.Sprintf("runner-%s-%s", *hostname, runnerIDStr)
	} else {
		// Append ID to provided name to ensure uniqueness
		*name = fmt.Sprintf("%s-%s", *name, runnerIDStr)
	}

	// Initialize logger (writes to both stdout and log file with rotation)
	// Use runner-specific log file name based on the final name
	sanitizedName := strings.ReplaceAll(*name, "/", "_")
	sanitizedName = strings.ReplaceAll(sanitizedName, "\\", "_")
	logFileName := fmt.Sprintf("runner-%s.log", sanitizedName)

	if err := logger.Init(*logDir, logFileName, *logMaxSize, *logMaxBackups, *logMaxAge); err != nil {
		log.Fatalf("Failed to initialize logger: %v", err)
	}
	defer func() {
		if l := logger.GetDefault(); l != nil {
			l.Close()
		}
	}()
	log.Printf("Logger initialized, continuing with startup...")
	log.Printf("Log rotation configured: max_size=%dMB, max_backups=%d, max_age=%d days", *logMaxSize, *logMaxBackups, *logMaxAge)

	log.Printf("About to create client...")
	client = runner.NewClient(*managerURL, *name, *hostname)
	log.Printf("Client created successfully")

	// Clean up any orphaned workspace directories from previous runs
	client.CleanupWorkspace()

	// Probe capabilities once at startup (before any registration attempts)
	log.Printf("Probing runner capabilities...")
	client.ProbeCapabilities()
	capabilities := client.GetCapabilities()
	capList := []string{}
	for cap, value := range capabilities {
		// Only show boolean true capabilities and numeric GPU counts
		if enabled, ok := value.(bool); ok && enabled {
			capList = append(capList, cap)
		} else if count, ok := value.(int); ok && count > 0 {
			capList = append(capList, fmt.Sprintf("%s=%d", cap, count))
		} else if count, ok := value.(float64); ok && count > 0 {
			capList = append(capList, fmt.Sprintf("%s=%.0f", cap, count))
		}
	}
	if len(capList) > 0 {
		log.Printf("Detected capabilities: %s", strings.Join(capList, ", "))
	} else {
		log.Printf("Warning: No capabilities detected")
	}

	// Register with API key (with retry logic)
	if *apiKeyFlag == "" {
		log.Fatalf("API key required (use --api-key or set API_KEY env var)")
	}

	// Retry registration with exponential backoff
	backoff := 1 * time.Second
	maxBackoff := 30 * time.Second
	maxRetries := 10
	retryCount := 0

	var runnerID int64

	for {
		var err error
		runnerID, _, _, err = client.Register(*apiKeyFlag)
		if err == nil {
			log.Printf("Registered runner with ID: %d", runnerID)
			break
		}

		// Check if it's a token error (invalid/expired/used token) - shutdown immediately
		errMsg := err.Error()
		if strings.Contains(errMsg, "token error:") {
			log.Fatalf("Registration failed (token error): %v", err)
		}

		// Only retry on connection errors or other retryable errors
		retryCount++
		if retryCount >= maxRetries {
			log.Fatalf("Failed to register runner after %d attempts: %v", maxRetries, err)
		}

		log.Printf("Registration failed (attempt %d/%d): %v, retrying in %v", retryCount, maxRetries, err, backoff)
		time.Sleep(backoff)
		backoff *= 2
		if backoff > maxBackoff {
			backoff = maxBackoff
		}
	}

	// Start WebSocket connection with reconnection
	go client.ConnectWebSocketWithReconnect()

	// Start heartbeat loop (for WebSocket ping/pong and HTTP fallback)
	go client.HeartbeatLoop()

	// ProcessTasks is now handled via WebSocket, but kept for HTTP fallback
	// WebSocket will handle task assignment automatically
	log.Printf("Runner started, connecting to manager via WebSocket...")

	// Set up signal handlers to kill processes on shutdown
	sigChan := make(chan os.Signal, 1)
	signal.Notify(sigChan, os.Interrupt, syscall.SIGTERM)

	go func() {
		sig := <-sigChan
		log.Printf("Received signal: %v, killing all processes and cleaning up...", sig)
		client.KillAllProcesses()
		// Cleanup happens in defer, but also do it here for good measure
		client.CleanupWorkspace()
		os.Exit(0)
	}()

	// Block forever
	select {}
}


func getEnv(key, defaultValue string) string {
	if value := os.Getenv(key); value != "" {
		return value
	}
	return defaultValue
}

func getEnvInt(key string, defaultValue int) int {
	if value := os.Getenv(key); value != "" {
		var result int
		if _, err := fmt.Sscanf(value, "%d", &result); err == nil {
			return result
		}
	}
	return defaultValue
}

// generateShortID generates a short random ID (8 hex characters)
func generateShortID() string {
	bytes := make([]byte, 4)
	if _, err := rand.Read(bytes); err != nil {
		// Fallback to timestamp-based ID if crypto/rand fails
		return fmt.Sprintf("%x", os.Getpid()^int(time.Now().Unix()))
	}
	return hex.EncodeToString(bytes)
}