package scanner

import (
	"os"
	"path/filepath"
	"strings"
	"time"
)

var videoExtensions = map[string]bool{
	".mkv":  true,
	".mp4":  true,
	".avi":  true,
	".m4v":  true,
	".webm": true,
	".ts":   true,
	".mov":  true,
}

type MediaFile struct {
	Path    string    `json:"-"`
	RelPath string    `json:"rel_path"`
	Name    string    `json:"name"`
	Size    int64     `json:"size"`
	ModTime time.Time `json:"mod_time"`
}

// DisplayName converts a filename into a human-readable display name.
func DisplayName(filename string) string {
	name := strings.TrimSuffix(filename, filepath.Ext(filename))
	name = strings.ReplaceAll(name, ".", " ")
	name = strings.ReplaceAll(name, "_", " ")
	return name
}

// Scan recursively walks rootDir and returns all video files found.
func Scan(rootDir string) ([]MediaFile, error) {
	var files []MediaFile

	err := filepath.WalkDir(rootDir, func(path string, d os.DirEntry, err error) error {
		if err != nil {
			return nil // skip inaccessible paths
		}
		if d.IsDir() {
			return nil
		}

		ext := strings.ToLower(filepath.Ext(d.Name()))
		if !videoExtensions[ext] {
			return nil
		}

		info, err := d.Info()
		if err != nil {
			return nil
		}

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

		files = append(files, MediaFile{
			Path:    path,
			RelPath: relPath,
			Name:    DisplayName(d.Name()),
			Size:    info.Size(),
			ModTime: info.ModTime(),
		})

		return nil
	})

	return files, err
}