// This file is part of the 64k demo project.
// It declares the FlashEffect - brief white flash on beat hits.

#pragma once

#include "gpu/effect.h"
#include "gpu/gpu.h"
#include "gpu/uniform_helper.h"

// Parameters for FlashEffect (set at construction time)
struct FlashEffectParams {
  float color[3] = {1.0f, 1.0f, 1.0f}; // Default: white
  float decay_rate = 0.98f;            // Default: fast decay
  float trigger_threshold = 0.7f;      // Default: trigger on strong beats
};

// Uniform data sent to GPU shader
// IMPORTANT: Must match WGSL struct layout with proper alignment
// vec3<f32> in WGSL has 16-byte alignment, not 12-byte!
struct FlashUniforms {
  float flash_intensity; // offset 0
  float intensity;       // offset 4
  float _pad1[2];        // offset 8-15 (padding for vec3 alignment)
  float color[3];        // offset 16-27 (vec3 aligned to 16 bytes)
  float _pad2;           // offset 28-31
};
static_assert(sizeof(FlashUniforms) == 32,
              "FlashUniforms must be 32 bytes for WGSL alignment");

class FlashEffect : public PostProcessEffect {
 public:
  // Backward compatibility constructor (uses default params)
  FlashEffect(const GpuContext& ctx);
  // New parameterized constructor
  FlashEffect(const GpuContext& ctx, const FlashEffectParams& params);
  void render(WGPURenderPassEncoder pass, float time, float beat,
              float intensity, float aspect_ratio) override;
  void update_bind_group(WGPUTextureView input_view) override;

 private:
  FlashEffectParams params_;
  UniformBuffer<FlashUniforms> uniforms_;
  float flash_intensity_ = 0.0f;
};