package spitfire

import (
	"fmt"
	"os"
	"os/exec"
	"path/filepath"
	"runtime"
	"sync"
	"time"
)

// Array to store errors
var errors []string

var (
	repoOperationsDone bool
	repoMutex          sync.Mutex
)

// SetGlobalEnv sets the MOZILLABUILD environment variable globally for the user (or system)
func SetGlobalEnv(variable, value string, scope string) error {
	fmt.Printf("⚙️ Setting environment variable: %s=%s (scope: %s)\n", variable, value, scope)
	if runtime.GOOS == "windows" {
		var cmd *exec.Cmd
		if scope == "user" {
			cmd = exec.Command("setx", variable, value) // Set for current user
		} else if scope == "system" {
			cmd = exec.Command("setx", variable, value, "/M") // Set for system (requires admin privileges)
		} else {
			return fmt.Errorf("❌ unknown scope: %s", scope)
		}

		// Run the command
		out, err := cmd.CombinedOutput()
		if err != nil {
			return fmt.Errorf("❌ failed to set environment variable %s=%s: %v\nOutput: %s", variable, value, err, string(out))
		}
		fmt.Printf("✅ Successfully set %s=%s\n", variable, value)
		return nil
	} else {
		return fmt.Errorf("❌ global environment variable setting is not supported on non-Windows systems")
	}
}

// Run an external command like scp or rsync
func runCommand(command string, args ...string) error {
	fmt.Printf("Running command: %s %v\n", command, args)
	cmd := exec.Command(command, args...)
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr
	return cmd.Run()
}

func runCommandInDir(dir string, name string, arg ...string) error {
	cmd := exec.Command(name, arg...)
	cmd.Dir = dir
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr
	return cmd.Run()
}

// Function to resolve paths using absolute path
func ResolvePath(path string) (string, error) {
	fmt.Printf("📍 Resolving path: %s\n", path)
	// Convert Unix-style slashes to the platform's native slashes
	path = filepath.FromSlash(path)

	// Get the absolute path
	absPath, err := filepath.Abs(path)
	if err != nil {
		return "", fmt.Errorf("❌ failed to resolve path: %s, error: %v", path, err)
	}
	fmt.Printf("   └─ Resolved to: %s\n", absPath)
	return absPath, nil
}

// Function to download Mozilla source if not present
func DownloadSource(sourcePath, sourceRepo string) error {
	fmt.Println("🔍 Checking Mozilla source repository...")
	if _, err := os.Stat(sourcePath); os.IsNotExist(err) {
		fmt.Println("📥 Mozilla source not found - cloning repository...")
		if err := runCommand("hg", "clone", sourceRepo, sourcePath); err != nil {
			return fmt.Errorf("❌ failed to clone Mozilla repository: %w", err)
		}
		fmt.Println("✅ Repository cloned successfully")
	} else {
		fmt.Println("ℹ️ Mozilla source already exists")
	}
	return nil
}

// Function to discard uncommitted changes
func DiscardChanges(sourcePath string) error {
	fmt.Println("🧹 Discarding uncommitted changes...")
	if err := runCommand("hg", "revert", "--all", "--no-backup", "-R", sourcePath); err != nil {
		return fmt.Errorf("❌ failed to revert changes: %w", err)
	}
	fmt.Println("✅ Changes discarded successfully")
	return nil
}

// Function to clean build
func CleanBuild(sourcePath string, fullClean bool) error {
	fmt.Println("🧼 Cleaning build...")
	if err := runCommand("hg", "revert", "--all", "--no-backup", "-R", sourcePath); err != nil {
		return fmt.Errorf("❌ failed to revert changes: %w", err)
	}

	if fullClean {
		fmt.Println("🧹 Performing full clean (clobber)...")
		machCmd := filepath.Join(sourcePath, "mach")
		if runtime.GOOS == "windows" {
			machCmd = filepath.Join(sourcePath, "mach.bat")
		}
		cmd := exec.Command(machCmd, "clobber")
		cmd.Dir = sourcePath // Run in the source directory
		if err := cmd.Run(); err != nil {
			return fmt.Errorf("❌ failed to clean build: %w", err)
		}
		fmt.Println("✅ Build artifacts cleaned successfully")
	}
	return nil
}

// UpdateRepo updates an existing repository if not already done
func UpdateRepo(sourcePath string) error {
	repoMutex.Lock()
	defer repoMutex.Unlock()

	if repoOperationsDone {
		fmt.Println("ℹ️ Repository operations already completed - skipping update")
		return nil
	}

	const maxRetries = 3
	var success bool

	for attempt := 1; attempt <= maxRetries; attempt++ {
		fmt.Printf("🔄 Update attempt %d/%d\n", attempt, maxRetries)

		if err := runCommandInDir(sourcePath, "hg", "pull", "-u"); err != nil {
			fmt.Println("❌ Update failed - removing corrupted repository")
			os.RemoveAll(sourcePath)
			if attempt < maxRetries {
				time.Sleep(10 * time.Second)
			}
			continue
		}

		success = true
		break
	}

	if success {
		repoOperationsDone = true
		return nil
	}
	return fmt.Errorf("failed to update repository after %d attempts", maxRetries)
}

// CloneRepo clones a fresh repository if not already done
func CloneRepo(sourcePath, url string) error {
	repoMutex.Lock()
	defer repoMutex.Unlock()

	if repoOperationsDone {
		fmt.Println("ℹ️ Repository operations already completed - skipping clone")
		return nil
	}

	const maxRetries = 3
	var success bool

	parentDir := filepath.Dir(sourcePath)
	if err := os.MkdirAll(parentDir, 0755); err != nil {
		return fmt.Errorf("failed to create parent directory: %w", err)
	}

	for attempt := 1; attempt <= maxRetries; attempt++ {
		fmt.Printf("📥 Clone attempt %d/%d\n", attempt, maxRetries)

		if err := runCommand("hg", "clone", "--stream", url, sourcePath); err != nil {
			fmt.Println("❌ Clone failed - cleaning up")
			os.RemoveAll(sourcePath)
			if attempt < maxRetries {
				time.Sleep(10 * time.Second)
			}
			continue
		}

		success = true
		break
	}

	if success {
		repoOperationsDone = true
		return nil
	}
	return fmt.Errorf("failed to clone repository after %d attempts", maxRetries)
}

// Function to update patches
func UpdatePatches(patchesDir, patchesRepo, sourcePath string) {
	fmt.Println("🔄 Updating patches...")
	if _, err := os.Stat(patchesDir); err == nil {
		fmt.Println("ℹ️ Patches directory exists - updating...")
		if err := os.Chdir(patchesDir); err != nil {
			errors = append(errors, "❌ Failed to navigate to patches directory")
			return
		}

		fmt.Println("🧹 Cleaning patches directory...")
		if err := runCommand("git", "clean", "-xdf"); err != nil {
			errors = append(errors, "❌ Failed to clean patches directory")
		}

		fmt.Println("💾 Stashing local changes...")
		_ = runCommand("git", "stash", "push", "--include-untracked")

		fmt.Println("📥 Fetching updates...")
		if err := runCommand("git", "fetch"); err != nil {
			errors = append(errors, "❌ Failed to fetch updates from patches repository")
		}

		fmt.Println("🔀 Rebasing changes...")
		if runCommand("git", "show-ref", "--verify", "--quiet", "refs/heads/main") == nil {
			if err := runCommand("git", "rebase", "origin/main"); err != nil {
				errors = append(errors, "❌ Failed to rebase updates from main branch")
			}
		} else if runCommand("git", "show-ref", "--verify", "--quiet", "refs/heads/master") == nil {
			if err := runCommand("git", "rebase", "origin/master"); err != nil {
				errors = append(errors, "❌ Failed to rebase updates from master branch")
			}
		} else {
			errors = append(errors, "❌ No valid branch (main or master) found in patches repository")
			return
		}

		if runCommand("git", "stash", "list") == nil {
			fmt.Println("↩️ Restoring stashed changes...")
			_ = runCommand("git", "stash", "pop")
		} else {
			fmt.Println("ℹ️ No stash entries found - skipping pop")
		}
	} else {
		fmt.Println("📥 Cloning patches repository...")
		if err := runCommand("git", "clone", patchesRepo, patchesDir); err != nil {
			errors = append(errors, "❌ Failed to clone patches repository")
		}
	}

	fmt.Println("📂 Copying files to source directory...")
	if runtime.GOOS == "windows" || !isMsys2() {
		fmt.Println("🖥️ Using robocopy for Windows...")
		if err := runCommand("robocopy", patchesDir, sourcePath, "*", "/S", "/XF", ".git", "/XD", ".git"); err != nil {
			errors = append(errors, "❌ Failed to copy files (Windows robocopy)")
		}
	} else {
		fmt.Println("🐧 Using rsync for Unix...")
		if err := runCommand("rsync", "-av", "--exclude=.git", patchesDir+"/", sourcePath+"/"); err != nil {
			errors = append(errors, "❌ Failed to copy files (rsync)")
		}
	}
}

// Function to configure Spitfire
func Configure(sourcePath string) error {
	fmt.Println("⚙️ Configuring Spitfire...")
	if err := os.Chdir(sourcePath); err != nil {
		return fmt.Errorf("❌ failed to navigate to source directory: %w", err)
	}

	machCmd := "./mach"
	if runtime.GOOS == "windows" {
		machCmd = ".\\mach"
	}
	fmt.Println("🔧 Running mach configure...")
	return runCommand(machCmd, "configure")
}

// Function to build Spitfire
func Build(sourcePath string) error {
	fmt.Println("🔨 Building Spitfire...")
	if err := os.Chdir(sourcePath); err != nil {
		return fmt.Errorf("❌ failed to navigate to source directory: %w", err)
	}

	machCmd := "./mach"
	if runtime.GOOS == "windows" {
		machCmd = ".\\mach"
	}
	fmt.Println("🏗️ Running mach build...")
	return runCommand(machCmd, "build")
}

// Function to run the project after build
func RunProject(sourcePath string) error {
	fmt.Println("🚀 Running the project...")

	// Resolve the build directory
	fmt.Println("🔍 Resolving build directory...")
	buildDir, err := ResolveBuildDir(sourcePath)
	if err != nil {
		return fmt.Errorf("❌ error resolving build directory: %w", err)
	}
	fmt.Printf("   ├─ Build directory: %s\n", buildDir)

	// List of possible binaries
	binaries := []string{"firefox", "Firefox", "spitfire", "Spitfire"}

	var binaryPath string

	// Check for the existence of binaries
	fmt.Println("🔎 Searching for executable binary...")
	for _, binary := range binaries {
		binaryPath = filepath.Join(buildDir, binary)
		if _, err := os.Stat(binaryPath); err == nil {
			fmt.Printf("✅ Found binary: %s\n", binaryPath)
			break
		}
		binaryPath = ""
	}

	if binaryPath == "" {
		return fmt.Errorf("❌ no suitable binary found to run the project")
	}

	// Create a unique profile directory for each run
	profilePath := filepath.Join(buildDir, fmt.Sprintf("profile_%d", time.Now().UnixNano()))
	fmt.Printf("📁 Creating temporary profile: %s\n", profilePath)
	if err := os.Mkdir(profilePath, 0755); err != nil {
		return fmt.Errorf("❌ failed to create profile directory: %w", err)
	}

	// Run the binary with the new profile
	fmt.Printf("⚡ Launching: %s -no-remote -profile %s\n", binaryPath, profilePath)
	cmd := exec.Command(binaryPath, "-no-remote", "-profile", profilePath)
	cmd.Stdout = os.Stdout
	cmd.Stderr = os.Stderr
	cmd.Stdin = os.Stdin

	fmt.Printf("✅ Running binary: %s with new profile at %s\n", binaryPath, profilePath)
	runErr := cmd.Run()

	// Clean up profile directory
	fmt.Println("🧹 Cleaning up temporary profile...")
	if removeErr := os.RemoveAll(profilePath); removeErr != nil {
		fmt.Printf("⚠️ Warning: failed to delete profile directory: %v\n", removeErr)
	} else {
		fmt.Println("✅ Profile directory cleaned successfully")
	}

	if runErr != nil {
		return fmt.Errorf("❌ failed to run the project: %w", runErr)
	}

	fmt.Println("🎉 Binary execution completed successfully")
	return nil
}

// ResolveBuildDir detects the build directory dynamically
func ResolveBuildDir(sourcePath string) (string, error) {
	fmt.Println("🔍 Detecting build directory...")
	// The expected build directory pattern
	globPattern := filepath.Join(sourcePath, "obj-*")

	// Find matching directories
	matches, err := filepath.Glob(globPattern)
	if err != nil {
		return "", fmt.Errorf("❌ error resolving build directory: %v", err)
	}
	if len(matches) == 0 {
		return "", fmt.Errorf("❌ build directory not found under %s", sourcePath)
	}
	full := filepath.Join(matches[0], "dist", "bin")

	// Return the first match (assumes one build directory exists)
	return full, nil
}

// Function to print collected errors
func PrintErrors() {
	if len(errors) > 0 {
		fmt.Println("❌ The following errors occurred during execution:")
		for _, err := range errors {
			fmt.Printf("   - %s\n", err)
		}
	}
}