using System.IO;

namespace Melskin.Appearance
{
    /// <summary>
    /// 主题偏好存储：简单文本文件：第一行 ThemeMode，第二行 ThemePalette
    /// 文件位置：%LOCALAPPDATA%\{LibraryNamespace}\theme.pref
    /// </summary>
    internal static class ThemePreferenceStore
    {
        private static readonly string Folder =
            Path.Combine(Environment.GetFolderPath(Environment.SpecialFolder.LocalApplicationData),
                ThemeManager.LibraryNamespace ?? "AppTheme");

        private static readonly string FilePath = Path.Combine(Folder, "theme.pref");

        public static void Save(ThemeMode themeMode, ThemePalette palette)
        {
            try
            {
                if (!Directory.Exists(Folder))
                    Directory.CreateDirectory(Folder);

                File.WriteAllLines(FilePath, new[] { themeMode.ToString(), palette.ToString() });
            }
            catch
            {
                // 忽略写入异常
            }
        }

        /// <summary>
        /// 读取偏好；成功返回 true，否则 false。不存在或解析失败不抛异常。
        /// </summary>
        public static bool TryLoad(out ThemeMode? mode, out ThemePalette? palette)
        {
            mode = null;
            palette = null;
            try
            {
                if (!File.Exists(FilePath))
                    return false;

                var lines = File.ReadAllLines(FilePath);
                if (lines.Length > 0 && Enum.TryParse(lines[0], true, out ThemeMode m))
                    mode = m;
                if (lines.Length > 1 && Enum.TryParse(lines[1], true, out ThemePalette p))
                    palette = p;

                return mode.HasValue || palette.HasValue;
            }
            catch
            {
                return false;
            }
        }
    }
}