package library

import (
	"database/sql"
	"strings"

	"git.noroutes.net/NoRoutes/vibetunes/internal/database"
)

// DirEntry is one immediate child of a directory in filesystem-style
// browsing (Subsonic's getIndexes/getMusicDirectory): either a
// subdirectory (Dir=true) or a media file.
type DirEntry struct {
	Name string
	Dir  bool
	File *database.MediaFile // set when Dir is false
}

// ListDirectory returns the immediate children of subPath within a music
// folder ("" for the folder root), built from media_files.relative_path.
// This is the foundation for filesystem-style browsing, kept separate
// from the ID3/tag model in library/index.go so neither is faked in
// terms of the other.
func ListDirectory(db *sql.DB, folderID, subPath string) ([]DirEntry, error) {
	files, err := database.ListMediaFilesForFolder(db, folderID)
	if err != nil {
		return nil, err
	}

	prefix := strings.Trim(subPath, "/")
	seen := make(map[string]bool)
	var out []DirEntry
	for _, f := range files {
		if f.Missing {
			continue
		}
		rel := f.RelativePath
		if prefix != "" {
			if !strings.HasPrefix(rel, prefix+"/") {
				continue
			}
			rel = rel[len(prefix)+1:]
		}
		parts := strings.SplitN(rel, "/", 2)
		name := parts[0]
		if name == "" || seen[name] {
			continue
		}
		if len(parts) == 2 {
			seen[name] = true
			out = append(out, DirEntry{Name: name, Dir: true})
			continue
		}
		seen[name] = true
		out = append(out, DirEntry{Name: name, Dir: false, File: f})
	}
	return out, nil
}