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

namespace SLSUtilities.Rendering.PostProcessing
{
    [System.Serializable, VolumeComponentMenu("SLS/Postprocessing/Space Pulse (Shockwave)")]
    public class SpacePulse : ScriptablePostProcessorVolume
    {
        public override CustomPostProcessInjectionPoint InjectionPoint => CustomPostProcessInjectionPoint.AfterPostProcess;
        public override int OrderInInjectionPoint => 56;

        [Header("Animation")]
        [Tooltip("The progress of the pulse. 0 = far center, 1+ = hits the camera and disappears. Drive this value using C#/Timeline.")]
        public ClampedFloatParameter pulseProgress = new(0f, 0f, 2f);
        
        [Header("Appearance")]
        [Tooltip("Emission Color of the pulse shockwave. Alpha controls the core brightness.")]
        public ColorParameter color = new(new Color(0f, 1f, 1f, 1f), true, true, true);
        [Tooltip("Thickness of the shockwave ring.")]
        public ClampedFloatParameter thickness = new(0.1f, 0.01f, 0.5f);
        
        [Header("Distortion")]
        [Tooltip("How strongly it warps/refracts the background pixels (positive pushes out, negative pulls in).")]
        public ClampedFloatParameter distortion = new(0.05f, -0.2f, 0.2f);
        [Tooltip("Chromatic aberration split on the edges of the pulse.")]
        public ClampedFloatParameter chromaticAberration = new(0.02f, 0f, 0.1f);

        [Header("Center")]
        [Tooltip("The vanishing point from where the pulse originates (0.5, 0.5 is screen center).")]
        public Vector2Parameter vfxCenter = new(new Vector2(0.5f, 0.5f));

        public override string GetShaderName() => "SLS/Postprocessing/SpacePulse";
        public override bool IsActive() => pulseProgress.value > 0f && pulseProgress.value < 1.5f;
        
        public override void Render(CommandBuffer cmd, ref RenderingData renderingData, RTHandle source, RTHandle target)
        {
            if (material == null) return;
            
            material.SetColor(InternalShaderHelpers.ID._SpacePulseColor, color.value);
            
            // Pack params into Vector4 for single pass
            Vector4 p = new Vector4(pulseProgress.value, thickness.value, distortion.value, chromaticAberration.value);
            material.SetVector(InternalShaderHelpers.ID._SpacePulseParams, p);
            material.SetVector(InternalShaderHelpers.ID._SpacePulseCenter, vfxCenter.value);

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