using UnityEngine;
using UnityEngine.UI;

namespace GameFramework
{
    /// <summary>
    /// 主菜单 UI 控制器。
    /// 支持开始游戏、设置、制作人员、退出游戏。
    /// 修复：场景重载后自动重新查找 UI 引用，避免 DontDestroyOnLoad 导致的空引用问题。
    /// </summary>
    public class MainMenuUIController : MonoBehaviour
    {
        [Header("Buttons")]
        [SerializeField] Button startButton;
        [SerializeField] Button settingsButton;
        [SerializeField] Button creditsButton;
        [SerializeField] Button quitButton;
        [SerializeField] Button storyReplayButton;

        [Header("剧情 PV")]
        [SerializeField] StoryPVPlayer storyPVPlayer;

        [Header("Settings Panel")]
        [SerializeField] GameObject settingsPanel;
        [SerializeField] Button settingsBackButton;

        [Header("Credits Panel")]
        [SerializeField] GameObject creditsPanel;
        [SerializeField] Button creditsCloseButton;

        [Header("新手引导")]
        [SerializeField] GameObject guidePanel;
        [SerializeField] Button guideStartButton;

        void Start()
        {
            // 自动查找（解决场景重载后引用失效问题）
            if (startButton == null)
                startButton = FindButton("StartButton");
            if (settingsButton == null)
                settingsButton = FindButton("SettingsButton");
            if (creditsButton == null)
                creditsButton = FindButton("CreditsButton");
            if (quitButton == null)
                quitButton = FindButton("QuitButton");
            if (storyReplayButton == null)
                storyReplayButton = FindButton("StoryReplayButton");
            if (storyPVPlayer == null)
            {
                // 使用 FindObjectsByType 包含 inactive 对象，避免找不到隐藏的 VideoOverlay
                var players = FindObjectsByType<StoryPVPlayer>(FindObjectsInactive.Include, FindObjectsSortMode.None);
                if (players.Length > 0)
                    storyPVPlayer = players[0];
            }

            if (settingsPanel == null)
                settingsPanel = GameObject.Find("SettingsPanel");
            if (settingsBackButton == null && settingsPanel != null)
                settingsBackButton = settingsPanel.GetComponentInChildren<Button>();

            if (creditsPanel == null)
                creditsPanel = GameObject.Find("CreditsPanel");
            if (creditsCloseButton == null && creditsPanel != null)
                creditsCloseButton = creditsPanel.GetComponentInChildren<Button>();

            if (guidePanel == null)
            {
                // transform.Find 可以找到非激活的子对象
                var guideTr = transform.Find("GuidePanel");
                guidePanel = guideTr != null ? guideTr.gameObject : null;
            }
            if (guideStartButton == null && guidePanel != null)
                guideStartButton = guidePanel.GetComponentInChildren<Button>(true);

            // 绑定按钮事件
            if (startButton != null)
                startButton.onClick.AddListener(OnStartClick);
            if (settingsButton != null)
                settingsButton.onClick.AddListener(OnSettingsClick);
            if (creditsButton != null)
                creditsButton.onClick.AddListener(OnCreditsClick);
            if (quitButton != null)
                quitButton.onClick.AddListener(OnQuitClick);
            if (storyReplayButton != null)
            {
                // 避免 Inspector 中已绑定的事件导致重复触发
                storyReplayButton.onClick.RemoveAllListeners();
                storyReplayButton.onClick.AddListener(OnStoryReplayClick);
            }

            if (settingsBackButton != null)
                settingsBackButton.onClick.AddListener(OnSettingsBackClick);
            if (creditsCloseButton != null)
                creditsCloseButton.onClick.AddListener(OnCreditsCloseClick);

            if (guideStartButton != null)
                guideStartButton.onClick.AddListener(OnGuideStartClick);

            // 确保面板初始关闭
            if (settingsPanel != null)
                settingsPanel.SetActive(false);
            if (creditsPanel != null)
                creditsPanel.SetActive(false);
            if (guidePanel != null)
                guidePanel.SetActive(false);
        }

        Button FindButton(string name)
        {
            var btn = GameObject.Find(name);
            return btn != null ? btn.GetComponent<Button>() : null;
        }

        void OnStartClick()
        {
            // 显示新手引导页，而非直接进入游戏
            if (guidePanel != null)
            {
                guidePanel.SetActive(true);
                Debug.Log("[MainMenu] 显示新手引导页");
            }
            else if (SceneLoader.Instance != null)
            {
                // 没有引导页则直接进入游戏
                SceneLoader.Instance.LoadGameplayScene();
            }
        }

        void OnGuideStartClick()
        {
            if (guidePanel != null)
                guidePanel.SetActive(false);

            if (SceneLoader.Instance != null)
                SceneLoader.Instance.LoadGameplayScene();
        }

        void OnSettingsClick()
        {
            if (settingsPanel != null)
                settingsPanel.SetActive(true);
        }

        void OnSettingsBackClick()
        {
            if (settingsPanel != null)
                settingsPanel.SetActive(false);
        }

        void OnCreditsClick()
        {
            if (creditsPanel != null)
            {
                creditsPanel.SetActive(true);
                Debug.Log($"[MainMenu] Showing credits panel: {creditsPanel.name}");
            }
            else
            {
                Debug.LogWarning("[MainMenu] creditsPanel not found! Make sure a GameObject named 'CreditsPanel' exists in the scene.");
            }
        }

        void OnCreditsCloseClick()
        {
            if (creditsPanel != null)
                creditsPanel.SetActive(false);
        }

        void OnQuitClick()
        {
#if UNITY_EDITOR
            UnityEditor.EditorApplication.isPlaying = false;
#else
            Application.Quit();
#endif
        }

        void OnStoryReplayClick()
        {
            if (storyPVPlayer != null)
            {
                Debug.Log($"[MainMenu] 播放 PV, StoryPVPlayer on: {storyPVPlayer.gameObject.name}");
                storyPVPlayer.Play();
            }
            else
            {
                Debug.LogWarning("[MainMenu] StoryPVPlayer 未配置！");
            }
        }
    }
}