using System.IO;
using UnityEngine;

namespace BaseGames.Core
{
    /// <summary>
    /// 全局设置管理器。从 GlobalSettingsSO 读取默认值，从文件加载用户覆盖。
    /// </summary>
    [DefaultExecutionOrder(-800)]
    public class SettingsManager : MonoBehaviour
    {
        private const string SettingsFileName = "settings.json";

        [SerializeField] private GlobalSettingsSO _defaultSettings;

        private GlobalSettingsData _current;
        private string SettingsFilePath => Path.Combine(Application.persistentDataPath, SettingsFileName);

        public GlobalSettingsData Current => _current;

        /// <summary>由 GameManager.Awake 调用。读取设置文件，应用音量/分辨率。</summary>
        public void Initialize()
        {
            _current = Load() ?? _defaultSettings?.CreateDefault() ?? new GlobalSettingsData();
            Apply(_current);
        }

        private GlobalSettingsData Load()
        {
            if (!File.Exists(SettingsFilePath)) return null;
            try
            {
                var json = File.ReadAllText(SettingsFilePath);
                return JsonUtility.FromJson<GlobalSettingsData>(json);
            }
            catch
            {
                return null;
            }
        }

        public void Save()
        {
            try
            {
                var json = JsonUtility.ToJson(_current, true);
                File.WriteAllText(SettingsFilePath, json);
            }
            catch (System.Exception e)
            {
                Debug.LogWarning($"[SettingsManager] 设置保存失败: {e.Message}");
            }
        }

        private void Apply(GlobalSettingsData data)
        {
            QualitySettings.vSyncCount = data.VSync ? 1 : 0;
            if (!data.VSync) Application.targetFrameRate = data.TargetFPS;

            if (data.FullScreen)
                Screen.fullScreenMode = FullScreenMode.FullScreenWindow;
        }

        // ── 音量设置（调用 AudioManager，Phase 1 接通）────────────────────
        public void SetMasterVolume(float v)  { _current.MasterVolume  = v; Save(); }
        public void SetBGMVolume(float v)     { _current.BGMVolume     = v; Save(); }
        public void SetSFXVolume(float v)     { _current.SFXVolume     = v; Save(); }
        public void SetAmbientVolume(float v) { _current.AmbientVolume = v; Save(); }

        // ── 画面设置 ──────────────────────────────────────────────────────
        public void SetResolution(int w, int h, FullScreenMode mode)
        {
            Screen.SetResolution(w, h, mode);
            _current.FullScreen = (mode != FullScreenMode.Windowed);
            Save();
        }
        public void SetVSync(bool enabled)
        {
            _current.VSync = enabled;
            QualitySettings.vSyncCount = enabled ? 1 : 0;
            Save();
        }
        public void SetTargetFrameRate(int fps)
        {
            _current.TargetFPS = fps;
            if (!_current.VSync) Application.targetFrameRate = fps;
            Save();
        }

        public void SetLanguage(string localeCode)
        {
            _current.Language = localeCode;
            Save();
        }
    }
}