using Echovoid.Runtime.Behavior.Rendering;
using UnityEngine;
using UnityEngine.Rendering;
using UnityEngine.Rendering.Universal;

namespace SLSFramework.Rendering.PostProcessing
{
    [System.Serializable, VolumeComponentMenu("SLS/Postprocessing/Advanced Chromatic Aberration")]
    public class AdvancedChromaticAberration : ScriptablePostProcessorVolume
    {
        // 建议放在 PostProcess 之后，作为最终的镜头效果
        public override CustomPostProcessInjectionPoint InjectionPoint => CustomPostProcessInjectionPoint.AfterPostProcess;
        public override int OrderInInjectionPoint => 20;

        [Header("Main Settings")]
        [Tooltip("色散总强度")]
        public ClampedFloatParameter intensity = new(0f, 0f, 1f);

        [Tooltip("扩散中心点 (0.5, 0.5 为屏幕中心)")]
        public Vector2Parameter center = new(new Vector2(0.5f, 0.5f));

        [Tooltip("RGB 分离权重。控制每个通道向外扩散的程度。\n例如 (1, 0, -1) 会让红蓝向相反方向分离，绿色不动。")]
        public Vector3Parameter channelSplit = new(new Vector3(1f, 0f, -1f));

        [Header("Dispersion Map (Broken Glass/Glitch)")]
        [Tooltip("输入的噪波贴图，用于打乱色散的方向")]
        public TextureParameter dispersionMap = new(null);
        
        [Tooltip("贴图对色散方向的影响力")]
        public ClampedFloatParameter dispersionStrength = new(0f, 0f, 2f);

        [Header("Jitter (Temporal Instability)")]
        [Tooltip("UV 采样抖动强度")]
        public ClampedFloatParameter jitterIntensity = new(0f, 0f, 1f);
        
        [Tooltip("抖动速度")]
        public FloatParameter jitterSpeed = new(10f);

        [Header("Masking")]
        [Tooltip("中心保留清晰的半径 (0-1)")]
        public ClampedFloatParameter maskRadius = new(0.2f, 0f, 1f);
        
        [Tooltip("遮罩边缘的软硬度")]
        public ClampedFloatParameter maskHardness = new(0.2f, 0.01f, 1f);

        public override string GetShaderName() => "SLS/Postprocessing/AdvancedChromaticAberration";

        public override void Render(CommandBuffer cmd, ref RenderingData renderingData, RTHandle source, RTHandle destination)
        {
            if (material == null) return;

            // Pack Params 1
            Vector4 p1 = new Vector4(
                intensity.value,
                center.value.x,
                center.value.y,
                maskRadius.value
            );
            
            // Pack Params 2
            Vector4 p2 = new Vector4(
                jitterIntensity.value,
                jitterSpeed.value,
                dispersionStrength.value,
                maskHardness.value
            );

            material.SetVector(InternalShaderHelpers.ID._ACA_Params1, p1);
            material.SetVector(InternalShaderHelpers.ID._ACA_Params2, p2);
            material.SetVector(InternalShaderHelpers.ID._ACA_Split, channelSplit.value);

            if (dispersionMap.value != null)
            {
                material.SetTexture(InternalShaderHelpers.ID._DispersionMap, dispersionMap.value);
            }

            Blitter.BlitCameraTexture(cmd, source, destination, material, 0);
        }

        public override bool IsActive()
        {
            // 只要有强度，或者有抖动，就需要渲染
            return intensity.value > 0f || jitterIntensity.value > 0f;
        }
    }
}