package steamimmich

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

func listScreenshots(steamUserdataDir string) (map[string][]string, error) {
	if _, err := os.Stat(steamUserdataDir); os.IsNotExist(err) {
		return nil, err
	}

	// Pattern: userdata/<steamid>/760/remote/<appid>/screenshots
	reAppDir := regexp.MustCompile(`.*/760/remote/([0-9]+)/screenshots$`)

	screenshotFiles := make(map[string][]string)

	err := filepath.WalkDir(steamUserdataDir, func(path string, d os.DirEntry, err error) error {
		if err != nil {
			return nil
		}
		if !d.IsDir() {
			return nil
		}

		if reAppDir.MatchString(path) {
			appid := reAppDir.FindStringSubmatch(path)[1]
			files, _ := os.ReadDir(path)
			for _, f := range files {
				if f.IsDir() {
					continue
				}
				name := strings.ToLower(f.Name())
				if strings.HasSuffix(name, ".jpg") ||
					strings.HasSuffix(name, ".jpeg") ||
					strings.HasSuffix(name, ".png") {
					fullPath := filepath.Join(path, f.Name())
					screenshotFiles[appid] = append(screenshotFiles[appid], fullPath)
				}
			}
		}
		return nil
	})

	if err != nil {
		return nil, err
	}

	return screenshotFiles, nil
}