package phases

import (
	"fmt"
	"os"
	"path/filepath"
	"time"

	"deb-bootc-compose/internal/types"
)

// BuildPhase handles package building using the build system
type BuildPhase struct {
	PhaseBase
}

// NewBuildPhase creates a new BuildPhase
func NewBuildPhase() *BuildPhase {
	return &BuildPhase{
		PhaseBase: NewPhaseBase("build", []string{"gather"}),
	}
}

// Run executes the build phase
func (p *BuildPhase) Run(engine types.Engine) error {
	logger := engine.GetLogger()
	logger.Printf("Starting build phase")
	
	// Get build system
	buildSystem := engine.GetBuildSystem()
	if buildSystem == nil {
		logger.Printf("No build system configured, skipping build phase")
		return nil
	}
	
	// Test build system connection
	if err := buildSystem.TestConnection(); err != nil {
		return fmt.Errorf("build system connection failed: %w", err)
	}
	
	// Get treefile and process variants
	treefile := engine.GetTreefile()
	
	for _, variant := range treefile.Variants {
		for _, arch := range variant.Architectures {
			logger.Printf("Building variant %s for architecture %s", variant.Name, arch)
			
			// Create build work directory
			buildWorkDir := filepath.Join(engine.GetWorkDir(), "variants", variant.Name, arch, "build")
			if err := os.MkdirAll(buildWorkDir, 0755); err != nil {
				return fmt.Errorf("failed to create build work directory: %w", err)
			}
			
			// Build packages for this variant/architecture
			if err := p.buildVariant(engine, buildWorkDir, variant, arch); err != nil {
				return fmt.Errorf("failed to build variant %s for architecture %s: %w", variant.Name, arch, err)
			}
			
			logger.Printf("Completed building variant %s for architecture %s", variant.Name, arch)
		}
	}
	
	logger.Printf("Build phase completed successfully")
	return nil
}

// buildVariant builds packages for a specific variant and architecture
func (p *BuildPhase) buildVariant(engine types.Engine, workDir string, variant types.Variant, arch string) error {
	logger := engine.GetLogger()
	buildSystem := engine.GetBuildSystem()
	
	// Get packages for this variant
	packages := engine.GetTreefile().GetPackagesForVariant(variant.Name, arch)
	
	// Create build environment
	logger.Printf("Creating build environment for architecture %s", arch)
	buildEnv, err := buildSystem.CreateBuildEnvironment(arch)
	if err != nil {
		return fmt.Errorf("failed to create build environment: %w", err)
	}
	
	// Ensure cleanup of build environment
	defer func() {
		if err := buildSystem.CleanupBuildEnvironment(buildEnv); err != nil {
			logger.Printf("Warning: failed to cleanup build environment: %v", err)
		}
	}()
	
	// Collect all packages to build
	allPackages := make([]string, 0)
	allPackages = append(allPackages, packages.Required...)
	allPackages = append(allPackages, packages.Optional...)
	allPackages = append(allPackages, packages.Recommended...)
	allPackages = append(allPackages, packages.Development...)
	allPackages = append(allPackages, packages.Kernel...)
	allPackages = append(allPackages, packages.Bootloader...)
	
	// Remove duplicates
	uniquePackages := make(map[string]bool)
	for _, pkg := range allPackages {
		uniquePackages[pkg] = true
	}
	
	// Build each package
	buildResults := make([]*types.BuildResult, 0)
	for pkgName := range uniquePackages {
		logger.Printf("Building package: %s", pkgName)
		
		// Build the package
		result, err := buildSystem.BuildPackage(pkgName, arch)
		if err != nil {
			logger.Printf("Warning: failed to build package %s: %v", pkgName, err)
			continue
		}
		
		// Wait for build to complete
		completedResult, err := buildSystem.WaitForBuild(result.ID, 30*time.Minute)
		if err != nil {
			logger.Printf("Warning: failed to wait for build of package %s: %v", pkgName, err)
			continue
		}
		
		if completedResult == nil {
			logger.Printf("Warning: build result is nil for package %s", pkgName)
			continue
		}
		
		buildResults = append(buildResults, completedResult)
		logger.Printf("Successfully built package: %s", pkgName)
	}
	
	// Write build results
	if err := p.writeBuildResults(workDir, buildResults); err != nil {
		return fmt.Errorf("failed to write build results: %w", err)
	}
	
	// Write build summary
	if err := p.writeBuildSummary(workDir, buildResults, variant, arch); err != nil {
		return fmt.Errorf("failed to write build summary: %w", err)
	}
	
	logger.Printf("Built %d packages for variant %s on architecture %s", len(buildResults), variant.Name, arch)
	return nil
}

// writeBuildResults writes build results to files
func (p *BuildPhase) writeBuildResults(workDir string, results []*types.BuildResult) error {
	// Create results directory
	resultsDir := filepath.Join(workDir, "results")
	if err := os.MkdirAll(resultsDir, 0755); err != nil {
		return fmt.Errorf("failed to create results directory: %w", err)
	}
	
	// Write successful builds
	successful := make([]string, 0)
	failed := make([]string, 0)
	
	for _, result := range results {
		if result.Result == "success" {
			successful = append(successful, result.PackageName)
		} else {
			failed = append(failed, result.PackageName)
		}
	}
	
	// Write successful packages
	if err := p.writePackageList(resultsDir, "successful", successful); err != nil {
		return fmt.Errorf("failed to write successful packages: %w", err)
	}
	
	// Write failed packages
	if err := p.writePackageList(resultsDir, "failed", failed); err != nil {
		return fmt.Errorf("failed to write failed packages: %w", err)
	}
	
	return nil
}

// writeBuildSummary writes a summary of the build process
func (p *BuildPhase) writeBuildSummary(workDir string, results []*types.BuildResult, variant types.Variant, arch string) error {
	summaryFile := filepath.Join(workDir, "build-summary.txt")
	
	summary := fmt.Sprintf(`Build Summary for Variant: %s
Architecture: %s
Timestamp: %s

Total Packages: %d
Successful Builds: %d
Failed Builds: %d

Successful Packages:
`, variant.Name, arch, time.Now().Format(time.RFC3339), len(results), 
		len(results), 0) // For now, assume all successful
	
	// Count successful builds
	successfulCount := 0
	for _, result := range results {
		if result.Result == "success" {
			successfulCount++
			summary += fmt.Sprintf("  - %s\n", result.PackageName)
		}
	}
	
	summary += fmt.Sprintf("\nFailed Packages:\n")
	failedCount := 0
	for _, result := range results {
		if result.Result != "success" {
			failedCount++
			summary += fmt.Sprintf("  - %s (%s)\n", result.PackageName, result.Result)
		}
	}
	
	// Update counts
	summary = fmt.Sprintf(`Build Summary for Variant: %s
Architecture: %s
Timestamp: %s

Total Packages: %d
Successful Builds: %d
Failed Builds: %d

Successful Packages:
`, variant.Name, arch, time.Now().Format(time.RFC3339), len(results), 
		successfulCount, failedCount) + summary
	
	if err := os.WriteFile(summaryFile, []byte(summary), 0644); err != nil {
		return fmt.Errorf("failed to write build summary: %w", err)
	}
	
	return nil
}

// writePackageList writes a list of packages to a file
func (p *BuildPhase) writePackageList(dir, name string, packages []string) error {
	if len(packages) == 0 {
		return nil
	}
	
	filename := filepath.Join(dir, name+".txt")
	content := ""
	for _, pkg := range packages {
		content += pkg + "\n"
	}
	
	if err := os.WriteFile(filename, []byte(content), 0644); err != nil {
		return fmt.Errorf("failed to write package list %s: %w", name, err)
	}
	
	return nil
}