using System;
using UnityEngine;
using UnityEngine.Serialization;

namespace UltimateWater.Internal
{
	[Serializable]
	public class Blur
	{
		[FormerlySerializedAs("blurComputeShader")]
		[HideInInspector]
		[SerializeField]
		protected ComputeShader _BlurComputeShader;

		[FormerlySerializedAs("blurShader")]
		[HideInInspector]
		[SerializeField]
		private Shader _BlurShader;

		[FormerlySerializedAs("computeShaderKernelIndex")]
		[SerializeField]
		[HideInInspector]
		private int _ComputeShaderKernelIndex;

		[Range(0f, 10f)]
		[SerializeField]
		[FormerlySerializedAs("iterations")]
		private int _Iterations = 1;

		[SerializeField]
		[FormerlySerializedAs("size")]
		private float _Size = 0.005f;

		private Material _BlurMaterial;

		private int _PassIndex;

		protected ComputeBuffer _ShaderWeights;

		public int Iterations
		{
			get
			{
				return _Iterations;
			}
			set
			{
				float totalSize = TotalSize;
				_Iterations = value;
				TotalSize = totalSize;
			}
		}

		public float Size
		{
			get
			{
				return _Size;
			}
			set
			{
				_Size = value;
			}
		}

		public float TotalSize
		{
			get
			{
				return _Size * (float)_Iterations;
			}
			set
			{
				_Size = value / (float)_Iterations;
			}
		}

		public Material BlurMaterial
		{
			get
			{
				if (_BlurMaterial == null)
				{
					if (_BlurShader == null)
					{
						Validate();
					}
					_BlurMaterial = new Material(_BlurShader)
					{
						hideFlags = HideFlags.DontSave
					};
				}
				return _BlurMaterial;
			}
			set
			{
				_BlurMaterial = value;
			}
		}

		public int PassIndex
		{
			get
			{
				return _PassIndex;
			}
			set
			{
				_PassIndex = value;
			}
		}

		public virtual void Validate(string shaderName, string computeShaderName = null, int kernelIndex = 0)
		{
			_BlurShader = Shader.Find(shaderName);
			if (computeShaderName != null)
			{
				_BlurComputeShader = Resources.Load<ComputeShader>(computeShaderName);
				_ComputeShaderKernelIndex = kernelIndex;
			}
			else
			{
				_BlurComputeShader = null;
			}
		}

		public void Dispose()
		{
			if (_BlurMaterial != null)
			{
				UnityEngine.Object.DestroyImmediate(_BlurMaterial);
			}
			if (_ShaderWeights != null)
			{
				_ShaderWeights.Release();
				_ShaderWeights = null;
			}
		}

		public void Validate()
		{
			Validate("UltimateWater/Utilities/Blur", "Shaders/Blurs");
		}

		public void Apply(RenderTexture target)
		{
			if (_Iterations != 0)
			{
				ApplyPixelShader(target);
			}
		}

		protected void ApplyComputeShader(RenderTexture target)
		{
			if (_ShaderWeights == null)
			{
				_ShaderWeights = new ComputeBuffer(4, 16);
				_ShaderWeights.SetData(new Color[4]
				{
					new Color(0.324f, 0.324f, 0.324f, 1f),
					new Color(0.232f, 0.232f, 0.232f, 1f),
					new Color(0.0855f, 0.0855f, 0.0855f, 1f),
					new Color(0.0205f, 0.0205f, 0.0205f, 1f)
				});
			}
			int num;
			switch (target.width)
			{
			case 128:
				num = _ComputeShaderKernelIndex;
				break;
			case 256:
				num = _ComputeShaderKernelIndex + 2;
				break;
			default:
				num = _ComputeShaderKernelIndex + 4;
				break;
			}
			int num2 = num;
			TemporaryRenderTexture temporary = RenderTexturesCache.GetTemporary(target.width, target.height, 0, target.format, true, true);
			_BlurComputeShader.SetBuffer(num2, "weights", _ShaderWeights);
			_BlurComputeShader.SetTexture(num2, "_MainTex", target);
			_BlurComputeShader.SetTexture(num2, "_Output", (RenderTexture)temporary);
			_BlurComputeShader.Dispatch(num2, 1, target.height, 1);
			num2++;
			_BlurComputeShader.SetBuffer(num2, "weights", _ShaderWeights);
			_BlurComputeShader.SetTexture(num2, "_MainTex", (RenderTexture)temporary);
			_BlurComputeShader.SetTexture(num2, "_Output", target);
			_BlurComputeShader.Dispatch(num2, target.width, 1, 1);
			temporary.Dispose();
		}

		protected void ApplyPixelShader(RenderTexture target)
		{
			Material blurMaterial = BlurMaterial;
			FilterMode filterMode = target.filterMode;
			target.filterMode = FilterMode.Bilinear;
			RenderTexture temporary = RenderTexture.GetTemporary(target.width, target.height, 0, target.format);
			temporary.filterMode = FilterMode.Bilinear;
			temporary.name = "[UWS] Blur - ApplyPixelShader temporary";
			for (int i = 0; i < _Iterations; i++)
			{
				float num = _Size * (1f + (float)i * 0.5f);
				blurMaterial.SetVector(ShaderVariables.Offset, new Vector4(num, 0f, 0f, 0f));
				Graphics.Blit(target, temporary, blurMaterial, _PassIndex);
				blurMaterial.SetVector(ShaderVariables.Offset, new Vector4(0f, num, 0f, 0f));
				Graphics.Blit(temporary, target, blurMaterial, _PassIndex);
			}
			target.filterMode = filterMode;
			RenderTexture.ReleaseTemporary(temporary);
		}
	}
}