package cluster

import (
	"context"
	"fmt"
	"os"
	"path/filepath"
	"strings"

	"github.com/spf13/cobra"

	"github.com/wild-cloud/wild-cli/internal/config"
	"github.com/wild-cloud/wild-cli/internal/environment"
	"github.com/wild-cloud/wild-cli/internal/external"
	"github.com/wild-cloud/wild-cli/internal/output"
)

var (
	servicesSkipInstall bool
)

func newServicesCommand() *cobra.Command {
	cmd := &cobra.Command{
		Use:   "services",
		Short: "Manage cluster services",
		Long: `Deploy and manage essential cluster services.

This command provides cluster service management including generation and deployment.

Examples:
  wild cluster services deploy
  wild cluster services deploy --skip-install`,
	}

	cmd.AddCommand(
		newServicesDeployCommand(),
	)

	return cmd
}

func newServicesDeployCommand() *cobra.Command {
	cmd := &cobra.Command{
		Use:   "deploy",
		Short: "Deploy cluster services",
		Long: `Deploy essential cluster services like ingress, DNS, and monitoring.

This generates service configurations and installs core Kubernetes services
including MetalLB, Traefik, cert-manager, and others.

Examples:
  wild cluster services deploy
  wild cluster services deploy --skip-install`,
		RunE: runServicesDeploy,
	}

	cmd.Flags().BoolVar(&servicesSkipInstall, "skip-install", false, "generate service configs but skip installation")

	return cmd
}

func runServicesDeploy(cmd *cobra.Command, args []string) error {
	output.Header("Cluster Services Deployment")

	// Initialize environment
	env := environment.New()
	if err := env.RequiresProject(); err != nil {
		return err
	}

	// Check external tools
	toolManager := external.NewManager()
	if err := toolManager.CheckTools(cmd.Context(), []string{"kubectl"}); err != nil {
		return fmt.Errorf("required tools not available: %w", err)
	}

	// Load configuration
	configMgr := config.NewManager(env.ConfigPath(), env.SecretsPath())

	// Check cluster configuration
	clusterName, err := getRequiredConfig(configMgr, "cluster.name", "")
	if err != nil {
		return fmt.Errorf("cluster configuration is missing: %w", err)
	}

	output.Info("Cluster: " + clusterName)

	// Check kubectl connectivity
	kubectl := toolManager.Kubectl()
	if err := checkKubectlConnectivity(cmd.Context(), kubectl); err != nil {
		return fmt.Errorf("kubectl is not configured or cluster is not accessible: %w", err)
	}

	output.Success("Cluster is accessible")

	// Phase 1: Generate cluster services setup files
	output.Info("\n=== Phase 1: Generating Service Configurations ===")
	if err := generateClusterServices(cmd.Context(), env, configMgr); err != nil {
		return fmt.Errorf("generating service configurations: %w", err)
	}

	// Phase 2: Install cluster services
	if !servicesSkipInstall {
		output.Info("\n=== Phase 2: Installing Cluster Services ===")
		if err := installClusterServices(cmd.Context(), env, kubectl); err != nil {
			return fmt.Errorf("installing cluster services: %w", err)
		}
	} else {
		output.Info("Skipping cluster services installation (--skip-install specified)")
		output.Info("You can install them later with: wild cluster services deploy")
	}

	// Summary output
	output.Success("Cluster Services Deployment Complete!")
	output.Info("")

	if !servicesSkipInstall {
		// Get internal domain for next steps
		internalDomain, err := configMgr.Get("cloud.internalDomain")
		domain := "your-internal-domain"
		if err == nil && internalDomain != nil {
			if domainStr, ok := internalDomain.(string); ok {
				domain = domainStr
			}
		}

		output.Info("Next steps:")
		output.Info("  1. Access the dashboard at: https://dashboard." + domain)
		output.Info("  2. Get the dashboard token with: wild dashboard token")
		output.Info("")
		output.Info("To verify components, run:")
		output.Info("  - kubectl get pods -n cert-manager")
		output.Info("  - kubectl get pods -n externaldns")
		output.Info("  - kubectl get pods -n kubernetes-dashboard")
		output.Info("  - kubectl get clusterissuers")
	} else {
		output.Info("Next steps:")
		output.Info("  1. Ensure your cluster is running and kubectl is configured")
		output.Info("  2. Install services with: wild cluster services deploy")
		output.Info("  3. Verify components are running correctly")
	}

	return nil
}

// checkKubectlConnectivity checks if kubectl can connect to the cluster
func checkKubectlConnectivity(ctx context.Context, kubectl *external.KubectlTool) error {
	// Try to get cluster info
	_, err := kubectl.Execute(ctx, "cluster-info")
	if err != nil {
		return fmt.Errorf("cluster not accessible: %w", err)
	}
	return nil
}

// generateClusterServices generates cluster service configurations
func generateClusterServices(ctx context.Context, env *environment.Environment, configMgr *config.Manager) error {
	// This function replicates wild-cluster-services-generate functionality
	output.Info("Generating cluster services setup files...")

	wcRoot := env.WCRoot()
	if wcRoot == "" {
		return fmt.Errorf("WC_ROOT not set")
	}

	sourceDir := filepath.Join(wcRoot, "setup", "cluster-services")
	destDir := filepath.Join(env.WildCloudDir(), "setup", "cluster-services")

	// Check if source directory exists
	if _, err := os.Stat(sourceDir); os.IsNotExist(err) {
		return fmt.Errorf("cluster setup source directory not found: %s", sourceDir)
	}

	// Force regeneration, removing existing files
	if _, err := os.Stat(destDir); err == nil {
		output.Info("Force regeneration enabled, removing existing files...")
		if err := os.RemoveAll(destDir); err != nil {
			return fmt.Errorf("removing existing setup directory: %w", err)
		}
	}

	// Create destination directory
	setupBaseDir := filepath.Join(env.WildCloudDir(), "setup")
	if err := os.MkdirAll(setupBaseDir, 0755); err != nil {
		return fmt.Errorf("creating setup directory: %w", err)
	}

	// Copy README if it doesn't exist
	readmePath := filepath.Join(setupBaseDir, "README.md")
	if _, err := os.Stat(readmePath); os.IsNotExist(err) {
		sourceReadme := filepath.Join(wcRoot, "setup", "README.md")
		if _, err := os.Stat(sourceReadme); err == nil {
			if err := copyFile(sourceReadme, readmePath); err != nil {
				output.Warning("Failed to copy README.md: " + err.Error())
			}
		}
	}

	// Create destination directory
	if err := os.MkdirAll(destDir, 0755); err != nil {
		return fmt.Errorf("creating destination directory: %w", err)
	}

	// Copy and compile cluster setup files
	output.Info("Copying and compiling cluster setup files from repository...")

	// First, copy root-level files from setup/cluster-services/
	if err := copyRootServiceFiles(sourceDir, destDir); err != nil {
		return fmt.Errorf("copying root service files: %w", err)
	}

	// Then, process each service directory
	if err := processServiceDirectories(sourceDir, destDir, configMgr); err != nil {
		return fmt.Errorf("processing service directories: %w", err)
	}

	// Verify required configuration
	if err := verifyServiceConfiguration(configMgr); err != nil {
		output.Warning("Configuration verification warnings: " + err.Error())
	}

	output.Success("Cluster setup files copied and compiled")
	output.Info("Generated setup directory: " + destDir)

	// List available services
	services, err := getAvailableServices(destDir)
	if err != nil {
		return fmt.Errorf("listing available services: %w", err)
	}

	output.Info("Available services:")
	for _, service := range services {
		output.Info("  - " + service)
	}

	return nil
}

// installClusterServices installs the cluster services
func installClusterServices(ctx context.Context, env *environment.Environment, kubectl *external.KubectlTool) error {
	setupDir := filepath.Join(env.WildCloudDir(), "setup", "cluster-services")

	// Check if cluster setup directory exists
	if _, err := os.Stat(setupDir); os.IsNotExist(err) {
		return fmt.Errorf("cluster services setup directory not found: %s", setupDir)
	}

	output.Info("Installing cluster services...")

	// Install services in dependency order
	servicesToInstall := []string{
		"metallb",
		"longhorn",
		"traefik",
		"coredns",
		"cert-manager",
		"externaldns",
		"kubernetes-dashboard",
		"nfs",
		"docker-registry",
	}

	// Filter to only include services that actually exist
	existingServices := []string{}
	for _, service := range servicesToInstall {
		installScript := filepath.Join(setupDir, service, "install.sh")
		if _, err := os.Stat(installScript); err == nil {
			existingServices = append(existingServices, service)
		}
	}

	if len(existingServices) == 0 {
		return fmt.Errorf("no installable services found")
	}

	output.Info(fmt.Sprintf("Services to install: %v", existingServices))

	// Install services
	installedCount := 0
	failedCount := 0

	for _, service := range existingServices {
		output.Info(fmt.Sprintf("\n--- Installing %s ---", service))

		installScript := filepath.Join(setupDir, service, "install.sh")
		if err := runServiceInstaller(ctx, setupDir, service, installScript); err != nil {
			output.Error(fmt.Sprintf("%s installation failed: %v", service, err))
			failedCount++
		} else {
			output.Success(fmt.Sprintf("%s installed successfully", service))
			installedCount++
		}
	}

	// Summary
	output.Info("\nInstallation Summary:")
	output.Success(fmt.Sprintf("Successfully installed: %d services", installedCount))
	if failedCount > 0 {
		output.Warning(fmt.Sprintf("Failed to install: %d services", failedCount))
	}

	if failedCount == 0 {
		output.Success("All cluster services installed successfully!")
	} else {
		return fmt.Errorf("some services failed to install")
	}

	return nil
}

// Helper functions (reused from setup/services.go with minimal modifications)

// copyRootServiceFiles copies root-level files from source to destination
func copyRootServiceFiles(sourceDir, destDir string) error {
	entries, err := os.ReadDir(sourceDir)
	if err != nil {
		return err
	}

	for _, entry := range entries {
		if !entry.IsDir() {
			srcPath := filepath.Join(sourceDir, entry.Name())
			dstPath := filepath.Join(destDir, entry.Name())
			output.Info("  Copying: " + entry.Name())
			if err := copyFile(srcPath, dstPath); err != nil {
				return err
			}
		}
	}

	return nil
}

// processServiceDirectories processes each service directory
func processServiceDirectories(sourceDir, destDir string, configMgr *config.Manager) error {
	entries, err := os.ReadDir(sourceDir)
	if err != nil {
		return err
	}

	// Create template engine
	engine, err := config.NewTemplateEngine(configMgr)
	if err != nil {
		return fmt.Errorf("creating template engine: %w", err)
	}

	for _, entry := range entries {
		if !entry.IsDir() {
			continue
		}

		serviceName := entry.Name()
		serviceDir := filepath.Join(sourceDir, serviceName)
		destServiceDir := filepath.Join(destDir, serviceName)

		output.Info("Processing service: " + serviceName)

		// Create destination service directory
		if err := os.MkdirAll(destServiceDir, 0755); err != nil {
			return err
		}

		// Process service files
		if err := processServiceFiles(serviceDir, destServiceDir, engine); err != nil {
			return fmt.Errorf("processing service %s: %w", serviceName, err)
		}
	}

	return nil
}

// processServiceFiles processes files in a service directory
func processServiceFiles(serviceDir, destServiceDir string, engine *config.TemplateEngine) error {
	entries, err := os.ReadDir(serviceDir)
	if err != nil {
		return err
	}

	for _, entry := range entries {
		srcPath := filepath.Join(serviceDir, entry.Name())
		dstPath := filepath.Join(destServiceDir, entry.Name())

		if entry.Name() == "kustomize.template" {
			// Compile kustomize.template to kustomize directory
			if entry.IsDir() {
				output.Info("  Compiling kustomize templates")
				kustomizeDir := filepath.Join(destServiceDir, "kustomize")
				if err := processTemplateDirectory(srcPath, kustomizeDir, engine); err != nil {
					return err
				}
			}
		} else if entry.IsDir() {
			// Copy other directories recursively
			if err := copyDir(srcPath, dstPath); err != nil {
				return err
			}
		} else {
			// Process individual files
			if err := processServiceFile(srcPath, dstPath, engine); err != nil {
				return err
			}
		}
	}

	return nil
}

// processServiceFile processes a single service file
func processServiceFile(srcPath, dstPath string, engine *config.TemplateEngine) error {
	content, err := os.ReadFile(srcPath)
	if err != nil {
		return err
	}

	// Check if file contains template syntax
	if strings.Contains(string(content), "{{") {
		output.Info("  Compiling: " + filepath.Base(srcPath))
		processed, err := engine.Process(string(content))
		if err != nil {
			return fmt.Errorf("processing template: %w", err)
		}
		return os.WriteFile(dstPath, []byte(processed), 0644)
	} else {
		return copyFile(srcPath, dstPath)
	}
}

// processTemplateDirectory processes an entire template directory
func processTemplateDirectory(srcDir, dstDir string, engine *config.TemplateEngine) error {
	if err := os.RemoveAll(dstDir); err != nil && !os.IsNotExist(err) {
		return err
	}

	return filepath.Walk(srcDir, func(path string, info os.FileInfo, err error) error {
		if err != nil {
			return err
		}

		relPath, err := filepath.Rel(srcDir, path)
		if err != nil {
			return err
		}

		dstPath := filepath.Join(dstDir, relPath)

		if info.IsDir() {
			return os.MkdirAll(dstPath, info.Mode())
		}

		content, err := os.ReadFile(path)
		if err != nil {
			return err
		}

		// Process template content
		if strings.Contains(string(content), "{{") {
			processed, err := engine.Process(string(content))
			if err != nil {
				return fmt.Errorf("processing template %s: %w", relPath, err)
			}
			content = []byte(processed)
		}

		// Create parent directory
		if err := os.MkdirAll(filepath.Dir(dstPath), 0755); err != nil {
			return err
		}

		return os.WriteFile(dstPath, content, info.Mode())
	})
}

// verifyServiceConfiguration verifies required configuration
func verifyServiceConfiguration(configMgr *config.Manager) error {
	missingConfig := []string{}

	// Check essential configuration values
	requiredConfigs := []string{
		"cluster.name",
		"cloud.domain",
		"cluster.ipAddressPool",
		"operator.email",
	}

	for _, configPath := range requiredConfigs {
		if value, err := configMgr.Get(configPath); err != nil || value == nil {
			missingConfig = append(missingConfig, configPath)
		}
	}

	if len(missingConfig) > 0 {
		return fmt.Errorf("missing required configuration values: %v", missingConfig)
	}

	return nil
}

// getAvailableServices returns list of available services
func getAvailableServices(setupDir string) ([]string, error) {
	var services []string

	entries, err := os.ReadDir(setupDir)
	if err != nil {
		return nil, err
	}

	for _, entry := range entries {
		if entry.IsDir() {
			installScript := filepath.Join(setupDir, entry.Name(), "install.sh")
			if _, err := os.Stat(installScript); err == nil {
				services = append(services, entry.Name())
			}
		}
	}

	return services, nil
}

// runServiceInstaller runs a service installation script
func runServiceInstaller(ctx context.Context, setupDir, serviceName, installScript string) error {
	// Change to the service directory and run install.sh
	serviceDir := filepath.Join(setupDir, serviceName)

	// Execute the install script using bash
	bashTool := external.NewBaseTool("bash", "bash")

	// Change to the service directory by setting working directory in the execution context
	oldDir, err := os.Getwd()
	if err != nil {
		return fmt.Errorf("getting current directory: %w", err)
	}

	if err := os.Chdir(serviceDir); err != nil {
		return fmt.Errorf("changing to service directory: %w", err)
	}
	defer func() {
		_ = os.Chdir(oldDir)
	}()

	_, err = bashTool.Execute(ctx, "install.sh")
	if err != nil {
		return fmt.Errorf("install script failed: %w", err)
	}

	return nil
}

// copyFile copies a single file
func copyFile(src, dst string) error {
	data, err := os.ReadFile(src)
	if err != nil {
		return err
	}

	return os.WriteFile(dst, data, 0644)
}

// copyDir recursively copies a directory
func copyDir(src, dst string) error {
	entries, err := os.ReadDir(src)
	if err != nil {
		return err
	}

	if err := os.MkdirAll(dst, 0755); err != nil {
		return err
	}

	for _, entry := range entries {
		srcPath := filepath.Join(src, entry.Name())
		dstPath := filepath.Join(dst, entry.Name())

		if entry.IsDir() {
			if err := copyDir(srcPath, dstPath); err != nil {
				return err
			}
		} else {
			if err := copyFile(srcPath, dstPath); err != nil {
				return err
			}
		}
	}

	return nil
}