using System.Collections;
using System.Collections.Generic;

using UnityEngine;
using UnityEngine.AI;
using UnityEngine.Events;
using UnityEngine.SceneManagement;
using UnityEngine.UI;

public class SceneLoader : MonoBehaviour
{
    public static SceneLoader Instance;

    public List<Vector3> ztPositions;
    public List<Vector3> ztRotations;

    /// <summary>
    /// 当前展厅索引
    /// </summary>
    public static int currentIndex = -1;

    public Slider slider;           // 滑动条
    int currentProgress;            // 当前进度
    int targetProgress;             // 目标进度

    public bool isAllLoaded;

    void Awake()
    {
        Instance = this;
    }

    private void Start()
    {
        currentProgress = 0;
        targetProgress = 0;

        GameObject obj = GameObject.Find("BtnExLoader" + currentIndex);
        if (obj != null)
        {
            obj.GetComponent<Image>().color = Color.cyan;
        }
    }

    AsyncOperation asyncOperation;

    /// <summary>
    /// 异步加载场景
    /// </summary>
    public IEnumerator LoadScene(int index)
    {
        if (index != currentIndex)
        {
            if (isAllLoaded)
            {
                SetCameraPosition(index);
                AudioManager.Instance.PlayBg(index);
            }
            else
            {
                slider.gameObject.SetActive(true);

                asyncOperation = SceneManager.LoadSceneAsync("ZT" + index);
                //  不允许场景立即激活 
                // 异步进度在 allowSceneActivation= false时，会卡在0.89999的一个值
                asyncOperation.allowSceneActivation = false;
                // 当异步加载小于0.9f的时候
                while (asyncOperation.progress < 0.9f)
                {
                    targetProgress = (int)(asyncOperation.progress * 100);
                    yield return LoadProgress();
                }
                //  循环后，当前进度已经为90了，所以需要设置目标进度到100；继续循环
                targetProgress = 100;

                yield return LoadProgress();

                currentIndex = index;
                asyncOperation.allowSceneActivation = true;
                asyncOperation.completed += AsyncOperation_completed;
                slider.gameObject.SetActive(false);
                currentProgress = 0;
                targetProgress = 0;
            }
        }
    }

    private void AsyncOperation_completed(AsyncOperation obj)
    {
        AudioManager.Instance.PlayBg(currentIndex);
    }

    public void SetCameraPosition(int index)
    {
        NavMeshAgent agent = FindObjectOfType<NavMeshAgent>();
        if (agent != null)
            agent.enabled = false;

        if (ztPositions.Count > index)
        {
            CommonData.MainCamera.transform.localPosition = ztPositions[index];
        }
        if (ztRotations.Count > index)
        {
            CommonData.MainCamera.transform.localRotation = Quaternion.Euler(ztRotations[index]);
        }

        if (agent != null)
            agent.enabled = true;
    }

    ShowPoint currentSPInfo;
    public void SetCameraPosition(ShowPoint info)
    {
        //if (currentIndex != info.ZT_Index)
        //{
        //    currentIndex = info.ZT_Index;
        //    AudioManager.Instance.PlayBg(currentIndex);
        //}
        currentSPInfo = info;
        LoadSceneData(info.ZT_Index, SetPostionOnLoaded );

    }

    void SetPostionOnLoaded()
    {
        SetCameraPosition(currentSPInfo.Position, currentSPInfo.Rotation);
    }

    public void SetCameraPosition(Vector3 pos, Vector3 rot)
    {
        NavMeshAgent agent = FindObjectOfType<NavMeshAgent>();
        if (agent != null)
            agent.enabled = false;

        CommonData.MainCamera.transform.localPosition = pos;
        CommonData.MainCamera.transform.localRotation = Quaternion.Euler(rot);

        if (agent != null)
            agent.enabled = true;
    }

    /// <summary>
    /// 由于需要两次调用，在这里进行简单封装
    /// </summary>
    /// <returns>等一帧</returns>
    private IEnumerator LoadProgress()
    {
        yield return new WaitForEndOfFrame();
        // 当前进度 < 目标进度时
        while (currentProgress < targetProgress)
        {
            ++currentProgress;
            slider.value = (float)currentProgress / 100;
            yield return new WaitForEndOfFrame();
        }
    }

    public void LoadSceneData(int newIndex, UnityAction onDataLoaded)
    {
        if (newIndex != SceneLoader.currentIndex)
        {
            SceneLoader.currentIndex = newIndex;
            LoadData(newIndex, onDataLoaded);
            AudioManager.Instance.PlayBg(newIndex);
        }
        else
        {
            if (onDataLoaded != null)
            {
                onDataLoaded();
            }
        }
    }

    void LoadData(int index, UnityAction onDataLoaded)
    {
        StartCoroutine(DataLoader<Data>.LoadDataDictionary(string.Format("SpotsZT{0}.json", index), onDataLoaded));
        StartCoroutine(DataLoader<Data>.LoadDataList(string.Format("Data_ZT{0}.json", index)));
    }
}