using UnityEngine;
using System.Collections;
using UnityEngine.UI;
using System.Collections.Generic;
using vnxbqy.UI;
using System;

public class CameraUtility
{

    static List<Blur> blurs = new List<Blur>();

    public static void RegisterBlur(Blur _blur)
    {
        if (_blur == null)
        {
            return;
        }

        if (!blurs.Contains(_blur))
        {
            blurs.Add(_blur);
            _blur.enabled = false;
        }
    }

    public static void UnRegisterBlur(Blur _blur)
    {
        if (blurs.Contains(_blur))
        {
            blurs.Remove(_blur);
        }
    }

    public static void AddCullingMask(Camera _camera, int _layer)
    {
        _camera.cullingMask |= (1 << _layer);
    }

    public static void RemoveCullingMask(Camera _camera, int _layer)
    {
        _camera.cullingMask &= ~(1 << _layer);
    }

    /// <summary>
    /// 将世界坐标转换为UI的坐标
    /// </summary>
    /// <param name="_camera"></param>
    /// <param name="_position"></param>
    /// <returns></returns>
    public static Vector3 ConvertToUIPosition(Camera _camera, Vector3 _position)
    {
        if (_camera == null || CameraManager.uiCamera == null)
        {
            return Vector3.zero;
        }

        var temp = _camera.WorldToViewportPoint(_position);
        var uiposition = CameraManager.uiCamera.ViewportToWorldPoint(temp);
        uiposition.z = 0;
        return uiposition;
    }

    public static Vector3 ScreenToUIPosition(Vector3 _screenPosition)
    {
        if (CameraManager.uiCamera == null)
        {
            return Vector3.zero;
        }

        var temp = CameraManager.uiCamera.ScreenToViewportPoint(_screenPosition);
        var uiposition = CameraManager.uiCamera.ViewportToWorldPoint(temp);
        uiposition.z = 0;
        return uiposition;
    }

    static Stack<Texture2D> screenShotCutTexturePool = new Stack<Texture2D>();

    static Texture2D RequireTexture2D()
    {
        if (screenShotCutTexturePool.Count > 0)
        {
            return screenShotCutTexturePool.Pop();
        }
        else
        {
            return new Texture2D(Screen.width, Screen.height, TextureFormat.RGB24, false);
        }
    }

    static void RecycleTexture2D(Texture2D _texture)
    {
        if (_texture != null)
        {
            if (Mathf.Abs(_texture.width - ResolutionUtility.currentResolution.x) > 10 || Mathf.Abs(_texture.height - ResolutionUtility.currentResolution.y) > 10)
            {
                //Resources.UnloadAsset(_texture);
            }
            else
            {
                screenShotCutTexturePool.Push(_texture);
            }
        }
    }

    public static void ScreenShotCut(RawImage _image, Action _callBack, bool _onlySceneCamera = false, bool blur = true)
    {
        if (_image == null)
        {
            return;
        }

        var screenRect = new Rect(0, 0, ResolutionUtility.currentResolution.x - 1, ResolutionUtility.currentResolution.y - 1);
        SnxxzGame.Instance.StartCoroutine(Co_ScreenShotCut(_image, _callBack, _onlySceneCamera, blur));
    }

    static WaitForEndOfFrame waitForEndOfFrame = new WaitForEndOfFrame();
    static IEnumerator Co_ScreenShotCut(RawImage _image, Action _callBack, bool _onlySceneCamera = false, bool blur = true)
    {
        if (_onlySceneCamera)
        {
            CameraManager.uiCamera.enabled = false;
        }

        if (blur)
        {
            for (int i = 0; i < blurs.Count; i++)
            {
                if (_onlySceneCamera && blurs[i].gameObject == CameraManager.uiCamera.gameObject)
                {
                    continue;
                }

                blurs[i].enabled = true;
            }
        }

        _image.color = _image.color.SetA(0);

        yield return waitForEndOfFrame;
        var texture2d = RequireTexture2D();
        var screenRect = new Rect(0, 0, ResolutionUtility.currentResolution.x - 1, ResolutionUtility.currentResolution.y - 1);
        texture2d.ReadPixels(screenRect, 0, 0, false);
        texture2d.Apply();
        _image.texture = texture2d;
        _image.color = _image.color.SetA(1);

        for (int i = 0; i < blurs.Count; i++)
        {
            blurs[i].enabled = false;
        }

        CameraManager.uiCamera.enabled = true;

        if (_callBack != null)
        {
            _callBack();
            _callBack = null;
        }
    }

    public static void StopShotCut(RawImage _image)
    {
        if (_image.texture != null)
        {
            RecycleTexture2D((Texture2D)_image.texture);
        }
    }

    public static void ScreenShotCut(Action<Texture2D> callBack)
    {
        SnxxzGame.Instance.StartCoroutine(Co_DelayScreenShotCut(callBack));
    }

    static IEnumerator Co_DelayScreenShotCut(Action<Texture2D> callBack)
    {
        yield return waitForEndOfFrame;
        try
        { 
            var texture2d = RequireTexture2D();
            var screenRect = new Rect(0, 0, ResolutionUtility.currentResolution.x - 1, ResolutionUtility.currentResolution.y - 1);

            texture2d.ReadPixels(screenRect, 0, 0, false);
            texture2d.Apply();
            callBack(texture2d);
        }
        catch (Exception e)
        {
            Debug.LogError("截屏发生错误：" + e);
        }
        callBack = null;
    }

    public static void StopShotCut(Texture2D tex)
    {
        RecycleTexture2D(tex);
    }

}