package cli

import (
	"context"
	"fmt"
	"strings"
	"time"

	"git.eeqj.de/sneak/vaultik/internal/log"
	"git.eeqj.de/sneak/vaultik/internal/s3"
	"github.com/spf13/cobra"
	"go.uber.org/fx"
)

// StoreApp contains dependencies for store commands
type StoreApp struct {
	S3Client   *s3.Client
	Shutdowner fx.Shutdowner
}

// NewStoreCommand creates the store command and subcommands
func NewStoreCommand() *cobra.Command {
	cmd := &cobra.Command{
		Use:   "store",
		Short: "Storage information commands",
		Long:  "Commands for viewing information about the S3 storage backend",
	}

	// Add subcommands
	cmd.AddCommand(newStoreInfoCommand())

	return cmd
}

// newStoreInfoCommand creates the 'store info' subcommand
func newStoreInfoCommand() *cobra.Command {
	return &cobra.Command{
		Use:   "info",
		Short: "Display storage information",
		Long:  "Shows S3 bucket configuration and storage statistics including snapshots and blobs",
		RunE: func(cmd *cobra.Command, args []string) error {
			return runWithApp(cmd.Context(), func(app *StoreApp) error {
				return app.Info(cmd.Context())
			})
		},
	}
}

// Info displays storage information
func (app *StoreApp) Info(ctx context.Context) error {
	// Get bucket info
	bucketName := app.S3Client.BucketName()
	endpoint := app.S3Client.Endpoint()

	fmt.Printf("Storage Information\n")
	fmt.Printf("==================\n\n")
	fmt.Printf("S3 Configuration:\n")
	fmt.Printf("  Endpoint: %s\n", endpoint)
	fmt.Printf("  Bucket:   %s\n\n", bucketName)

	// Count snapshots by listing metadata/ prefix
	snapshotCount := 0
	snapshotCh := app.S3Client.ListObjectsStream(ctx, "metadata/", true)
	snapshotDirs := make(map[string]bool)

	for object := range snapshotCh {
		if object.Err != nil {
			return fmt.Errorf("listing snapshots: %w", object.Err)
		}
		// Extract snapshot ID from path like metadata/2024-01-15-143052-hostname/
		parts := strings.Split(object.Key, "/")
		if len(parts) >= 2 && parts[0] == "metadata" && parts[1] != "" {
			snapshotDirs[parts[1]] = true
		}
	}
	snapshotCount = len(snapshotDirs)

	// Count blobs and calculate total size by listing blobs/ prefix
	blobCount := 0
	var totalSize int64

	blobCh := app.S3Client.ListObjectsStream(ctx, "blobs/", false)
	for object := range blobCh {
		if object.Err != nil {
			return fmt.Errorf("listing blobs: %w", object.Err)
		}
		if !strings.HasSuffix(object.Key, "/") { // Skip directories
			blobCount++
			totalSize += object.Size
		}
	}

	fmt.Printf("Storage Statistics:\n")
	fmt.Printf("  Snapshots:  %d\n", snapshotCount)
	fmt.Printf("  Blobs:      %d\n", blobCount)
	fmt.Printf("  Total Size: %s\n", formatBytes(totalSize))

	return nil
}

// formatBytes formats bytes into human-readable format
func formatBytes(bytes int64) string {
	const unit = 1024
	if bytes < unit {
		return fmt.Sprintf("%d B", bytes)
	}
	div, exp := int64(unit), 0
	for n := bytes / unit; n >= unit; n /= unit {
		div *= unit
		exp++
	}
	return fmt.Sprintf("%.1f %cB", float64(bytes)/float64(div), "KMGTPE"[exp])
}

// runWithApp creates the FX app and runs the given function
func runWithApp(ctx context.Context, fn func(*StoreApp) error) error {
	var result error
	rootFlags := GetRootFlags()

	// Use unified config resolution
	configPath, err := ResolveConfigPath()
	if err != nil {
		return err
	}

	err = RunWithApp(ctx, AppOptions{
		ConfigPath: configPath,
		LogOptions: log.LogOptions{
			Verbose: rootFlags.Verbose,
			Debug:   rootFlags.Debug,
		},
		Modules: []fx.Option{
			s3.Module,
			fx.Provide(func(s3Client *s3.Client, shutdowner fx.Shutdowner) *StoreApp {
				return &StoreApp{
					S3Client:   s3Client,
					Shutdowner: shutdowner,
				}
			}),
		},
		Invokes: []fx.Option{
			fx.Invoke(func(app *StoreApp, shutdowner fx.Shutdowner) {
				result = fn(app)
				// Shutdown after command completes
				go func() {
					time.Sleep(100 * time.Millisecond) // Brief delay to ensure clean shutdown
					if err := shutdowner.Shutdown(); err != nil {
						log.Error("Failed to shutdown", "error", err)
					}
				}()
			}),
		},
	})

	if err != nil {
		return err
	}
	return result
}