using System.IO;
using UnityEngine;
using UnityEngine.UI;
using System.Collections;

public class GameManager : MonoBehaviour
{
    public BeatmapManager beatmapManager;  // 负责加载和管理谱面
    public NoteSpawner noteSpawner;       // 音符生成器
    public AudioSource musicSource;       // 音乐播放器
    [Header("paths")]
    // 变量声明不再从静态变量中读取
    public string JSONPath;
    public string audioPath;
    public string bgPicPath;

    // Optional: sprite renderer to show background image
    public SpriteRenderer backgroundRenderer;

    // NEW: UI Text to display banflag content from pressStart
    [Header("Debug / Test")]
    public Text banflagTextUI;

    private bool pauseSubscribed = false;

    private void SubscribeToPauseManager()
    {
        if (pauseSubscribed) return;
        // prefer the singleton, but try to find in scene if null
        var pm = PauseManager.Instance ?? FindObjectOfType<PauseManager>();
        if (pm != null)
        {
            pm.OnPauseStateChanged += HandlePauseStateChanged;
            pauseSubscribed = true;
        }
    }

    private void UnsubscribeFromPauseManager()
    {
        if (!pauseSubscribed) return;
        var pm = PauseManager.Instance ?? FindObjectOfType<PauseManager>();
        if (pm != null)
        {
            pm.OnPauseStateChanged -= HandlePauseStateChanged;
        }
        pauseSubscribed = false;
    }

    private void OnEnable()
    {
        SubscribeToPauseManager();
    }

    private void OnDisable()
    {
        UnsubscribeFromPauseManager();
    }

    private void HandlePauseStateChanged(bool isPaused)
    {
        if (musicSource != null)
        {
            if (isPaused)
            {
                musicSource.Pause();
            }
            else
            {
                musicSource.UnPause();
            }
        }
    }

    void Start()
    {
        Debug.Log("GameManager Start() 被调用");

        // 检查关键组件是否为空
        if (beatmapManager == null) Debug.LogError("beatmapManager 未赋值！");
        if (noteSpawner == null) Debug.LogError("noteSpawner 未赋值！");
        if (musicSource == null) Debug.LogError("musicSource 未赋值！");

        // 如果 pressStart 已经读取了 banflag 内容，则把它显示在 UI（如果分配了）
        if (banflagTextUI != null && !string.IsNullOrEmpty(pressStart.banflagContent))
        {
            banflagTextUI.text = pressStart.banflagContent;
            Debug.Log("Displayed banflag content from pressStart into banflagTextUI.");
        }

        // 在 test mode 下使用外部路径预加载资源并暂停系统，等待按空格继续
        if (GameConfig.testMode)
        {
            // 延迟赋值：在 Start() 中获取静态路径，此时 pressStart.cs 已经运行并更新了它们
            JSONPath = pressStart.testmode_beatmapJSON_path;
            audioPath = pressStart.testmode_audioFile_path;
            bgPicPath = pressStart.testmode_bgPicFile_path;

            Debug.Log("Test mode active: using external paths to preload assets");

            // also update banflag UI if content exists
            if (banflagTextUI != null && !string.IsNullOrEmpty(pressStart.banflagContent))
            {
                banflagTextUI.text = pressStart.banflagContent;
            }

            StartCoroutine(HandleTestModeStartup());
            return;
        }
        else
        {
            StartCoroutine(HandleNormalModeStartup());
        }
    }

    private IEnumerator HandleTestModeStartup()
    {
        // Preload audio from audioPath (absolute)
        if (!string.IsNullOrEmpty(audioPath))
        {
            if (!File.Exists(audioPath))
            {
                Debug.LogError($"TestMode audio file not found: {audioPath}");
            }
            else
            {
                // 注意：这里仍然使用过时的 WWW，建议替换为 UnityWebRequest
                string url = "file://" + audioPath;
                using (var www = new WWW(url))
                {
                    yield return www;
                    if (!string.IsNullOrEmpty(www.error))
                    {
                        Debug.LogError($"加载测试模式音频失败: {www.error}");
                    }
                    else
                    {
                        try
                        {
                            AudioClip clip = www.GetAudioClip(false, false);
                            if (clip == null)
                            {
                                Debug.LogError("从文件获取 AudioClip 失败");
                            }
                            else
                            {
                                musicSource.clip = clip;
                                musicSource.loop = false;
                                Debug.Log("TestMode audio loaded into AudioSource");
                            }
                        }
                        catch (System.Exception ex)
                        {
                            Debug.LogError($"将音频设置到 AudioSource 时出错: {ex}");
                        }
                    }
                }
            }
        }
        else
        {
            Debug.LogWarning("TestMode audioPath 未配置。");
        }

        // Preload background image into sprite renderer
        if (backgroundRenderer != null)
        {
            if (!string.IsNullOrEmpty(bgPicPath))
            {
                if (!File.Exists(bgPicPath))
                {
                    Debug.LogError($"TestMode background image not found: {bgPicPath}");
                }
                else
                {
                    byte[] imgBytes = null;
                    try
                    {
                        imgBytes = File.ReadAllBytes(bgPicPath);
                    }
                    catch (System.Exception ex)
                    {
                        Debug.LogError($"读取背景图片文件出错: {ex}");
                    }

                    if (imgBytes != null)
                    {
                        Texture2D tex = new Texture2D(2, 2);
                        if (tex.LoadImage(imgBytes))
                        {
                            Sprite s = Sprite.Create(tex, new Rect(0, 0, tex.width, tex.height), new Vector2(0.5f, 0.5f));
                            backgroundRenderer.sprite = s;

                            // 【修改点：设置 SpriteRenderer 透明度为 255 (1.0f)】
                            Color color = backgroundRenderer.color;
                            color.a = 1.0f;
                            backgroundRenderer.color = color;

                            // 保持比例不变的最大适应由场景布局决定，记录 assignment
                            Debug.Log("Background sprite assigned (ensure your SpriteRenderer size fits scene)");
                        }
                        else
                        {
                            Debug.LogError($"无法从字节创建 Texture2D: {bgPicPath}");
                        }
                    }
                }
            }
            else
            {
                Debug.LogWarning("TestMode bgPicPath 未配置。");
            }
        }
        else
        {
            Debug.LogWarning("backgroundRenderer 未配置，跳过背景加载。");
        }

        // Read JSON from JSONPath and parse via BeatmapManager.ParseJsonOnly
        if (!string.IsNullOrEmpty(JSONPath))
        {
            if (!File.Exists(JSONPath))
            {
                Debug.LogError($"TestMode beatmap JSON not found: {JSONPath}");
                yield break; // abort
            }

            string jsonContent = null;
            try
            {
                jsonContent = File.ReadAllText(JSONPath);
            }
            catch (System.Exception ex)
            {
                Debug.LogError($"读取 TestMode JSON 文件出错: {ex}");
                yield break;
            }

            bool parsed = beatmapManager.ParseJsonOnly(jsonContent);
            if (!parsed)
            {
                Debug.LogError("ParseJsonOnly 失败，停止启动测试模式。");
                yield break;
            }

            // Do not start spawning yet. We will start after unpausing.
            Debug.Log("Beatmap parsed (deferred start). Ready to unpause.");
        }
        else
        {
            Debug.LogError("TestMode JSONPath 未配置。");
            yield break;
        }

        // Pause the system until Space pressed
        // Ensure we are subscribed before invoking pause so we track audio state
        SubscribeToPauseManager();
        PauseManager.Instance?.Pause(true);
        UpdateStatusOnConsole("Paused: press Space to start playback");

        // Wait for space key down (use unscaled input loop)
        while (!Input.GetKeyDown(KeyCode.Space))
        {
            yield return null;
        }

        // Resume using PauseManager
        PauseManager.Instance?.Pause(false);

        // Start spawning using the parsed beatmap
        if (beatmapManager.beatmap != null)
        {
            beatmapManager.LoadBeatmap(beatmapManager.beatmap);
        }
        else
        {
            Debug.LogError("启动播放失败：beatmap 未解析或为空");
            yield break;
        }

        // If audio clip was loaded into musicSource.clip, play now with delay from parsed globalDelaySeconds
        float delaySeconds = beatmapManager != null ? beatmapManager.globalDelaySeconds : 0f;
        if (musicSource.clip != null)
        {
            if (delaySeconds > 0f)
            {
                musicSource.PlayDelayed(delaySeconds);
                Debug.Log($"Scheduled test-mode music to play after {delaySeconds} seconds.");
            }
            else
            {
                musicSource.Play();
            }
        }
        else
        {
            Debug.LogWarning("TestMode: no audio clip loaded into AudioSource; skipping play.");
        }

        UpdateStatusOnConsole("Playback started");
    }

    private IEnumerator HandleNormalModeStartup()
    {
        // 加载谱面但不生成音符
        string beatmapFilePath = Path.Combine(Application.streamingAssetsPath, "Emilia_demo.json");

        if (!File.Exists(beatmapFilePath))
        {
            Debug.LogError($"谱面文件不存在: {beatmapFilePath}");
            yield break;
        }

        string json = File.ReadAllText(beatmapFilePath);
        bool parsed = beatmapManager.ParseJsonOnly(json);
        if (!parsed)
        {
            Debug.LogError("ParseJsonOnly 失败");
            yield break;
        }

        // 暂停系统
        SubscribeToPauseManager();
        PauseManager.Instance?.Pause(true);
        UpdateStatusOnConsole("Paused: press Space to start playback");

        // 等待空格
        while (!Input.GetKeyDown(KeyCode.Space))
        {
            yield return null;
        }

        // 恢复
        PauseManager.Instance?.Pause(false);

        // 生成音符
        if (beatmapManager.beatmap != null)
        {
            noteSpawner.LoadBeatmap(beatmapManager.beatmap);
        }
        else
        {
            Debug.LogError("beatmap 未解析");
            yield break;
        }

        // 播放背景音乐（延迟播放由 beatmapManager.globalDelaySeconds 决定）
        if (!string.IsNullOrEmpty(beatmapManager.parsedMusicFile))
        {
            AudioClip musicClip = Resources.Load<AudioClip>(beatmapManager.parsedMusicFile);
            if (musicClip == null)
            {
                Debug.LogError($"音乐文件加载失败: {beatmapManager.parsedMusicFile}");
            }
            else
            {
                musicSource.clip = musicClip;
                float delay = beatmapManager.globalDelaySeconds;
                if (delay > 0f)
                {
                    musicSource.PlayDelayed(delay);
                    Debug.Log($"Scheduled music to play after {delay} seconds.");
                }
                else
                {
                    musicSource.Play();
                }
            }
        }
        else
        {
            Debug.LogError("谱面中 musicFile 为空！");
        }

        UpdateStatusOnConsole("Playback started");
    }

    private void UpdateStatusOnConsole(string message)
    {
        Debug.Log(message);
    }
}