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// Sampler cache - deduplicates samplers across effects
#pragma once
#include <map>

// Forward declarations (users must include gpu.h)
struct WGPUDeviceImpl;
typedef struct WGPUDeviceImpl* WGPUDevice;
struct WGPUSamplerImpl;
typedef struct WGPUSamplerImpl* WGPUSampler;

#include "platform/platform.h"

struct SamplerSpec {
  WGPUAddressMode u, v;
  WGPUFilterMode mag, min;
  uint16_t anisotropy;

  bool operator<(const SamplerSpec& o) const {
    if (u != o.u) return u < o.u;
    if (v != o.v) return v < o.v;
    if (mag != o.mag) return mag < o.mag;
    if (min != o.min) return min < o.min;
    return anisotropy < o.anisotropy;
  }
};

class SamplerCache {
  std::map<SamplerSpec, WGPUSampler> cache_;
  SamplerCache() = default;

public:
  static SamplerCache& Get() {
    static SamplerCache instance;
    return instance;
  }

  WGPUSampler get_or_create(WGPUDevice device, const SamplerSpec& spec) {
    auto it = cache_.find(spec);
    if (it != cache_.end()) return it->second;

    WGPUSamplerDescriptor desc{};
    desc.addressModeU = spec.u;
    desc.addressModeV = spec.v;
    desc.magFilter = spec.mag;
    desc.minFilter = spec.min;
    desc.maxAnisotropy = spec.anisotropy;
    WGPUSampler sampler = wgpuDeviceCreateSampler(device, &desc);
    cache_[spec] = sampler;
    return sampler;
  }

  // Common presets
  static SamplerSpec linear() {
    return {WGPUAddressMode_Repeat, WGPUAddressMode_Repeat,
            WGPUFilterMode_Linear, WGPUFilterMode_Linear, 1};
  }
  static SamplerSpec clamp() {
    return {WGPUAddressMode_ClampToEdge, WGPUAddressMode_ClampToEdge,
            WGPUFilterMode_Linear, WGPUFilterMode_Linear, 1};
  }
};