// Uniform data to be passed from application -> shader.
cbuffer Uniforms {
  float4x4 u_Projection;
  float4x4 u_View;
  float4x4 u_Model;
  float4 u_Color;
  int u_HasTexture; // Changed from bool to int for compatibility
}

// Per-vertex attributes to be assembled from bound vertex buffers.
struct AssembledVertex {
  float3 position : POSITION;
  float2 texcoord : TEXCOORD0;
};

// Output of the vertex shader, and input to the fragment shader.
struct CoarseVertex {
  float2 texcoord : TEXCOORD0;
  float4 position : SV_Position; // Needed for rasterization
};

// Output of the fragment shader.
struct Fragment {
  float4 color : SV_Target; // SV_Target is required for color output
};

// Combined Texture and Sampler (avoids linking issues)
Texture2D textureMap;
SamplerState textureSampler;

// Vertex Shader
[shader("vertex")]
CoarseVertex vertexMain(AssembledVertex assembledVertex) {
  CoarseVertex output;

  // Transform vertex position using Model-View-Projection matrix
  float4 worldPosition = mul(u_Model, float4(assembledVertex.position, 1.0));
  float4 viewPosition = mul(u_View, worldPosition);
  output.position = mul(u_Projection, viewPosition);

  // Pass through texture coordinates
  output.texcoord = assembledVertex.texcoord;

  return output;
}

// Fragment Shader
[shader("fragment")]
Fragment fragmentMain(CoarseVertex coarseVertex) {
  Fragment output;

  // Sample the texture if a texture is bound
  if (u_HasTexture != 0) {
    output.color = textureMap.Sample(textureSampler, coarseVertex.texcoord);
  } else {
    // Use the uniform color if no texture is bound
    output.color = u_Color;
  }

  return output;
}