# MusicInfo —— 对标 POC/assets/root/musicinfo.py：默认曲目常量 + 上次战场曲目持久化。
#
# 参考（musicinfo.py）：
#   METIN2THEMA = "M2BG.mp3"
#   loginMusic  = "login_window.mp3"
#   createMusic = "characterselect.mp3"
#   selectMusic = "characterselect.mp3"
#   fieldMusic  = METIN2THEMA
#   SaveLastPlayFieldMusic() / LoadLastPlayFieldMusic()  →  文件 "BGM/lastplay.inf"
#
# 用法：
#   const MusicInfo = preload("res://musicinfo.gd")
#   MusicInfo.fieldMusic                       # -> "M2BG.mp3"
#   MusicInfo.save_last_play_field_music("x.mp3")
#   MusicInfo.load_last_play_field_music()     # -> "x.mp3" 或 ""
extends RefCounted

const METIN2THEMA := "M2BG.mp3"
const loginMusic := "login_window.mp3"
const createMusic := "characterselect.mp3"
const selectMusic := "characterselect.mp3"      # 选人页
const fieldMusic := METIN2THEMA

# 参考写死 "BGM/lastplay.inf"（相对客户端目录）；Godot 侧落到用户可写目录。
const LAST_PLAY_DIR := "user://BGM"
const LAST_PLAY_PATH := "user://BGM/lastplay.inf"

# musicInfo.SaveLastPlayFieldMusic(name)
static func save_last_play_field_music(name: String) -> void:
	if name == "":
		return
	DirAccess.make_dir_recursive_absolute(LAST_PLAY_DIR)
	var f := FileAccess.open(LAST_PLAY_PATH, FileAccess.WRITE)
	if f:
		f.store_string(name)
		f.close()

# musicInfo.LoadLastPlayFieldMusic() -> 曲目名（无记录时空串）
static func load_last_play_field_music() -> String:
	if not FileAccess.file_exists(LAST_PLAY_PATH):
		return ""
	var f := FileAccess.open(LAST_PLAY_PATH, FileAccess.READ)
	if f == null:
		return ""
	var s := f.get_as_text()
	f.close()
	return s.strip_edges()