package main

import (
	"fmt"
	"log"
	"os"
	"os/exec"
	"path/filepath"
	"strconv"
	"strings"
	"sync"
	"time"

	spm "weforge.xyz/Spitfire/SPM"
)

// -------------------------------------------------------------------
// GLOBALS
// -------------------------------------------------------------------
var (
	copyingInProgress int32
	updateStatusMsg   string
	browserCmd        *exec.Cmd
	browserMutex      sync.Mutex // Protects the lock file map
	isBackgroundMode  bool
)

// StateFile holds the update state from our INI
type StateFile struct {
	IsUpdating bool
	Progress   int32
	Stage      string // "Idle","Downloading","Decompressing","ReadyToInstall","Installing","Complete","Failed"
}

// -------------------------------------------------------------------
// LOG INIT
// -------------------------------------------------------------------
func init() {
	log.SetFlags(0)
	log.SetPrefix("[UPDATER] ")
}

// -------------------------------------------------------------------
// INI Helpers
// -------------------------------------------------------------------
func getSpmDir() string {
	installDir, err := spm.GetDefaultInstallDir()
	if err != nil {
		log.Println("Warning: Using '.' for spmDir =>", err)
		return "."
	}
	spmDir := filepath.Join(installDir, "spm")
	_ = os.MkdirAll(spmDir, 0755)
	return spmDir
}

func getStateFilePath() string {
	return filepath.Join(getSpmDir(), "update_state.ini")
}

func WriteState(isUpdating bool, progress int32, stage string) {
	content := "[UpdateState]\n" +
		fmt.Sprintf("IsUpdating=%v\n", isUpdating) +
		fmt.Sprintf("Progress=%d\n", progress) +
		fmt.Sprintf("Stage=%s\n", stage)
	_ = os.WriteFile(getStateFilePath(), []byte(content), 0644)
}

func ReadState() StateFile {
	sf := StateFile{}
	data, err := os.ReadFile(getStateFilePath())
	if err != nil {
		return sf
	}

	lines := strings.Split(string(data), "\n")
	for _, line := range lines {
		line = strings.TrimSpace(line)
		if line == "" || strings.HasPrefix(line, "[") {
			continue
		}
		parts := strings.SplitN(line, "=", 2)
		if len(parts) != 2 {
			continue
		}
		key := strings.TrimSpace(parts[0])
		val := strings.TrimSpace(parts[1])
		switch key {
		case "IsUpdating":
			sf.IsUpdating = (val == "true")
		case "Progress":
			if i, errAtoi := strconv.Atoi(val); errAtoi == nil {
				sf.Progress = int32(i)
			}
		case "Stage":
			sf.Stage = val
		}
	}
	return sf
}

// -------------------------------------------------------------------
// BROWSER
// -------------------------------------------------------------------
// LaunchBrowser starts the browser and creates a unique lock file in the spmdir.
func LaunchBrowser() {
	spmDir := getSpmDir()

	// Generate a unique lock file name (based on timestamp)
	lockFileName := fmt.Sprintf("browser_lock_%d.lock", time.Now().UnixNano())
	lockFilePath := filepath.Join(spmDir, lockFileName)

	// Create the lock file
	file, err := os.Create(lockFilePath)
	if err != nil {
		fmt.Println("Failed to create lock file:", err)
		return
	}
	file.Close()

	// Run the browser process and wait for it to finish
	fmt.Println("Starting browser...")
	err = spm.RunAndWait()
	if err != nil {
		fmt.Println("Browser process encountered an error:", err)
	}

	// Remove the lock file after the browser finishes
	fmt.Printf("Removing lock file: %s\n", lockFilePath)
	err = os.Remove(lockFilePath)
	if err != nil {
		fmt.Println("Failed to remove lock file:", err)
	} else {
		fmt.Println("Lock file removed successfully.")
	}
}

// IsBrowserRunning checks if there are any browser lock files in the spmdir.
func IsBrowserRunning() bool {
	spmDir := getSpmDir()

	// Look for lock files in the spmdir
	lockFiles, err := filepath.Glob(filepath.Join(spmDir, "browser_lock_*.lock"))
	if err != nil {
		fmt.Println("Error checking for lock files:", err)
		return false
	}

	// Return true if at least one lock file is found
	return len(lockFiles) > 0
}

// -------------------------------------------------------------------
// BACKGROUND SERVICE
// -------------------------------------------------------------------
func runBackgroundUpdater() {
	// Delete the update_state.ini file on startup
	stateFilePath := getStateFilePath()
	if _, err := os.Stat(stateFilePath); err == nil {
		err = os.Remove(stateFilePath)
		if err != nil {
			log.Printf("Failed to delete state file %s: %v\n", stateFilePath, err)
		} else {
			log.Printf("Deleted state file: %s\n", stateFilePath)
		}
	} else {
		log.Printf("State file does not exist, no need to delete: %s\n", stateFilePath)
	}

	// Remove all lock files in the spmdir
	spmDir := getSpmDir()
	lockFilePattern := filepath.Join(spmDir, "browser_lock_*.lock")
	lockFiles, err := filepath.Glob(lockFilePattern)
	if err != nil {
		log.Printf("Failed to scan for lock files in %s: %v\n", spmDir, err)
	} else {
		for _, lockFile := range lockFiles {
			err := os.Remove(lockFile)
			if err != nil {
				log.Printf("Failed to delete lock file %s: %v\n", lockFile, err)
			} else {
				log.Printf("Deleted lock file: %s\n", lockFile)
			}
		}
	}

	log.Println("Background updater started (no GUI).")

	// Start a separate goroutine to periodically update the progress in update_state.ini
	go func() {
		for {
			// Get current progress and task from spm
			progress, task := spm.GetProgress()

			// Determine if the updater is in "Copying files to install directory" stage
			isUpdating := task == "Copying files to install directory"

			// Write the state to the update_state.ini file
			WriteState(isUpdating, int32(progress), task)

			// Sleep for 1 hour before updating the progress again
			time.Sleep(1 * time.Hour)
		}
	}()

	// Main loop for periodic AutoDownloadUpdates and AutoInstallUpdates
	for {
		// Run AutoDownloadUpdates every 10 seconds
		err := spm.AutoDownloadUpdates()
		if err != nil {
			log.Printf("AutoDownloadUpdates failed: %v\n", err)
			WriteState(false, 0, fmt.Sprintf("Update failed: %v", err))
			time.Sleep(10 * time.Second)
			continue
		}

		// Check if the browser is running
		if IsBrowserRunning() {
			log.Println("Browser is running. Waiting before installing updates.")
			time.Sleep(10 * time.Second)
			continue
		}

		// If the browser is not running, run AutoInstallUpdates
		log.Println("\nBrowser is not running. Starting installation of updates.")
		err = spm.AutoInstallUpdates()
		if err != nil {
			log.Printf("AutoInstallUpdates failed: %v\n", err)
			WriteState(false, 0, fmt.Sprintf("Installation failed: %v", err))
			time.Sleep(10 * time.Second)
			continue
		}

		// Write to update_state.ini indicating updates are complete
		WriteState(false, 100, "Complete")
		log.Println("Updates installed successfully. Waiting before next check.")

		// Wait 10 seconds before checking again
		time.Sleep(10 * time.Second)
	}
}

// -------------------------------------------------------------------
// MAIN
// -------------------------------------------------------------------
func main() {
	if len(os.Args) > 1 && os.Args[1] == "--update-service" {
		isBackgroundMode = true
		runBackgroundUpdater()
		return
	} else {
		log.Println("Launcher started (foreground mode).")
		ShowUpdateWindow()
	}
	fmt.Println("Exiting launcher.")
}