using UnityEngine;
using UnityEngine.EventSystems;
using UnityEngine.UI;

/// <summary>
///     UI 界面上的特效管理类 绑定在特效的最外层物体上（特效的Prefab上）
/// </summary>
public class UIParticleSystem : UIBehaviour
{
    private static Shader _replaceShader;
    private int _LastAddOrder;
    private bool _started;

    private UiMaskListener _maskListener;

    protected override void OnEnable()
    {
        base.OnEnable();
        var renders = gameObject.GetComponentsInChildren<Renderer>();
        for (var i = 0; i < renders.Length; i++)
        {
            var renderroder = renders[i].sortingOrder;
            renders[i].sortingOrder = renderroder > 0 ? renderroder : 1;
            var meshRender = renders[i].gameObject.GetComponent<MeshRendererOrder>();
            if (meshRender != null)
                meshRender.sortingOrder = renderroder > 0 ? renderroder : 1;
        }

        Init();
        if (_started)
            SetCullListening(true);
    }

    protected override void Start()
    {
        base.Start();
        var mask = gameObject.GetComponentInParent<Mask>();
        if (mask != null)
        {
            _maskListener = mask.gameObject.EnsureComponent<UiMaskListener>();
            SetCullListening(true);
        }
        _started = true;
    }

    private void SetCullListening(bool isEnable)
    {
        if (_maskListener != null)
        {
            _maskListener.onMaskUndate -= Cull;
            if (isEnable)
                _maskListener.onMaskUndate += Cull;
        }
    }
    
    public void Init()
    {
        var wndParent = gameObject.GetComponentsInParent<WindowSign>();
        if (wndParent.Length <= 0)
            return;
        wndParent[0].SetWndDirty();
    }

    protected override void OnDisable()
    {
        base.OnDisable();
        var wndParent = gameObject.GetComponentsInParent<WindowSign>();
        if (wndParent.Length <= 0)
            return;
        wndParent[0].SetWndDirty();
        SetCullListening(false);
    }
    
    public void SortParticle(int order)
    {
        if (order > 0)
            order -= _LastAddOrder;
        var renders = gameObject.GetComponentsInChildren<Renderer>();
        for (var i = 0; i < renders.Length; i++)
        {
            var renderroder = renders[i].sortingOrder;
            renderroder += order;
            renders[i].sortingOrder = renderroder > 0 ? renderroder : 1;

            var meshRender = renders[i].gameObject.GetComponent<MeshRendererOrder>();
            if (meshRender != null)
                meshRender.sortingOrder = renderroder > 0 ? renderroder : 1;
        }
        _LastAddOrder += order;
    }

    //检查一下是否是在UI的裁剪区域
    private void Cull(UiMaskListener listener)
    {
        var renderers = gameObject.GetComponentsInChildren<Renderer>();
        if (renderers.Length < 1)
            return;
        if (_maskListener != null)
        {
            var rect = _maskListener.rect;
            for (var i = 0; i < renderers.Length; i++)
            {
                var renderItem = renderers[i];
                for (var j = 0; j < renderItem.sharedMaterials.Length; j++)
                {
                    if (renderItem.sharedMaterials[j] != null)
                    {
                        var shader = renderItem.sharedMaterials[j].shader;
                        if (shader != null)
                        {
                            var cull = false;
                            if (shader.name.Contains("AdditiveAlphaWrite"))
                            {
                                if (_replaceShader == null)
                                    _replaceShader = Shader.Find("Zhanyou/Particles/AdditiveAlphaWriteMask");
                                if (_replaceShader != null)
                                {
                                    renderItem.materials[j].shader = _replaceShader;
                                    cull = true;
                                }
                            }
                            else if (shader.name.Contains("AlphaBlendAlphaWrite"))
                            {
                                cull = true;
                            }
                            if (cull)
                            {
                                var material = renderItem.materials[j];
                                material.SetFloat("_UseMask", 2);
                                material.SetVector("_ClipRect", rect);
                            }
                        }
                    }
                }
            }
        }
    }
}