using TMPro;
using UnityEngine;
using UnityEngine.UI;
using UnityEngine.EventSystems;
using BaseGames.Core;

namespace BaseGames.UI
{
    /// <summary>
    /// 设置面板控制器（架构 10_UIModule §7）。
    /// 驱动 SettingsManager 的音量与画面设置，并从当前配置初始化控件值。
    /// </summary>
    public class SettingsPanelController : MonoBehaviour, IFocusable
    {
        // ISettingsService 通过 ServiceLocator 获取，无需 Inspector 直接注入具体类，
        // 支持测试场景替换 Mock 实现。
        private ISettingsService _settings;

        [Header("音量滑条")]
        [SerializeField] private Slider _masterVolume;
        [SerializeField] private Slider _bgmVolume;
        [SerializeField] private Slider _sfxVolume;
        [SerializeField] private Slider _ambientVolume;

        [Header("画面")]
        [SerializeField] private Toggle      _vSyncToggle;
        [SerializeField] private TMP_Dropdown _fpsDropdown;    // 30 / 60 / 120 / 无限

        [Header("按键重绑定")]
        [SerializeField] private GameObject _rebindPanelRoot;  // RebindPanel GameObject

        private static readonly int[] FpsOptions = { 30, 60, 120, -1 };

        private void OnEnable()
        {
            _settings = ServiceLocator.GetOrDefault<ISettingsService>();
            if (_settings == null) return;
            var data = _settings.Current;

            // 初始化控件值（先移除监听再设置值再添加，防止面板重开时重复注册）
            InitSlider(_masterVolume, data.MasterVolume,  v => _settings.SetMasterVolume(v));
            InitSlider(_bgmVolume,    data.BGMVolume,     v => _settings.SetBGMVolume(v));
            InitSlider(_sfxVolume,    data.SFXVolume,     v => _settings.SetSFXVolume(v));
            InitSlider(_ambientVolume,data.AmbientVolume, v => _settings.SetAmbientVolume(v));

            if (_vSyncToggle != null)
            {
                _vSyncToggle.onValueChanged.RemoveAllListeners();
                _vSyncToggle.isOn = data.VSync;
                _vSyncToggle.onValueChanged.AddListener(v => _settings.SetVSync(v));
            }

            if (_fpsDropdown != null)
            {
                _fpsDropdown.onValueChanged.RemoveAllListeners();
                int idx = System.Array.IndexOf(FpsOptions, data.TargetFPS);
                _fpsDropdown.value = idx >= 0 ? idx : 1; // default 60
                _fpsDropdown.onValueChanged.AddListener(i =>
                    _settings.SetTargetFrameRate(FpsOptions[Mathf.Clamp(i, 0, FpsOptions.Length - 1)]));
            }

            // 手柄导航：打开设置面板时将焦点置于主音量滑条
            EventSystem.current?.SetSelectedGameObject(_masterVolume?.gameObject);
        }

        // ── 辅助 ──────────────────────────────────────────────────────────────

        private static void InitSlider(Slider slider, float value, UnityEngine.Events.UnityAction<float> onChange)
        {
            if (slider == null) return;
            slider.onValueChanged.RemoveAllListeners();
            slider.value = value;
            slider.onValueChanged.AddListener(onChange);
        }

        // ── IFocusable ────────────────────────────────────────────────────────

        /// <summary>面板恢复为栈顶时将焦点移回主音量滑条。</summary>
        public void OnFocusRestored()
            => EventSystem.current?.SetSelectedGameObject(_masterVolume?.gameObject);
    }
}