// Metal definitions
#define NS_PRIVATE_IMPLEMENTATION
#define CA_PRIVATE_IMPLEMENTATION
#define MTL_PRIVATE_IMPLEMENTATION

#include 
#include 

#include 
#include 
#include 
#include 

class Timer
{
    private:
        std::chrono::high_resolution_clock::time_point start_time;
    public:
        Timer() {}
        void begin() {start_time = std::chrono::high_resolution_clock::now();}
        void end(const char * str = "Duration: ")
        {
            auto end_time = std::chrono::high_resolution_clock::now();
            std::chrono::duration duration = end_time - start_time;
            printf("%s%.6f ms\n", str, duration.count());
        }
};

int main()
{
    Timer t,tt;
    
    NS::Error* error;
    auto gpuHandler = MTL::CreateSystemDefaultDevice();
    auto commandQueue = gpuHandler->newCommandQueue();
    auto gpuFunctionsLibrary = gpuHandler->newLibrary(NS::String::string("kernel void dummyKernel(){}", NS::ASCIIStringEncoding), nullptr, &error);
    auto functionName = NS::String::string("dummyKernel", NS::ASCIIStringEncoding);
    auto gpuFunction = gpuFunctionsLibrary->newFunction(functionName);
    auto computePipelineState = gpuHandler->newComputePipelineState(gpuFunction, &error);
    auto gridSize = MTL::Size::Make(1,1,1);
    auto groupSize = MTL::Size::Make(32,1,1);

    tt.begin();
    for(int k = 0; k < 100; k += 1)
    {
        t.begin();
        auto commandBuffer = commandQueue->commandBuffer();
        auto commandEncoder = commandBuffer->computeCommandEncoder();
        commandEncoder->setComputePipelineState(computePipelineState);
        commandEncoder->dispatchThreadgroups(gridSize, groupSize);
        commandEncoder->endEncoding();
        t.end("Encoding: ");
        
        t.begin();
        commandBuffer->commit();
        t.end("Commit:   ");
        
        t.begin();
        commandBuffer->waitUntilCompleted();
        t.end("Wait:     ");
        
        double gpuTimeSec = commandBuffer->GPUEndTime() - commandBuffer->GPUStartTime();
        printf("GPU:      %.6f ms\n", gpuTimeSec * 1000);
        
        printf("---\n");
        
        //commandBuffer->release();
        //commandEncoder->release();
    }
    tt.end("Total: ");
}