salmanoff/stimBuffApis/livoxGen1/openClCollatingAndMeshingEngine.h

#ifndef _LIVOX_GEN1_OPENCL_COLLATING_AND_MESHING_ENGINE_H
#define _LIVOX_GEN1_OPENCL_COLLATING_AND_MESHING_ENGINE_H

#include <boostAsioLinkageFix.h>
#include <cstdint>
#include <cstddef>
#include <memory>
#include <functional>
#include <iostream>
#include <stdexcept>
#include <chrono>
#define CL_TARGET_OPENCL_VERSION 120
#include <CL/cl.h>
#include <asynchronousLoop.h>
#include <callback.h>
#include <spinLock.h>
#include <user/stimulusFrame.h>
#include "stagingBuffer.h"
#include "frameAssemblyDesc.h"

namespace smo {
namespace stim_buff {

class PcloudStimulusBuffer;

class OpenClCollatingAndMeshingEngine
{
public:
	explicit OpenClCollatingAndMeshingEngine(PcloudStimulusBuffer& parent);
	~OpenClCollatingAndMeshingEngine();

	// Non-copyable, movable
	OpenClCollatingAndMeshingEngine(
		const OpenClCollatingAndMeshingEngine&) = delete;
	OpenClCollatingAndMeshingEngine& operator=(
		const OpenClCollatingAndMeshingEngine&) = delete;
	OpenClCollatingAndMeshingEngine(
		OpenClCollatingAndMeshingEngine&&) = default;
	OpenClCollatingAndMeshingEngine& operator=(
		OpenClCollatingAndMeshingEngine&&) = default;

	bool setup();
	void finalize();

	typedef std::function<void(bool, StimulusFrame&)>
		compactCollateAndMeshFrameReqCbFn;
	void compactCollateAndMeshFrameReq(
		AsynchronousLoop& asyncLoop, StimulusFrame& stimulusFrame,
		Callback<compactCollateAndMeshFrameReqCbFn> callback);

private:
	// Callback function types
	typedef std::function<void(cl_int)> compactKernelCbFn;
	typedef std::function<void(cl_int)> collateKernelCbFn;

	bool startCompactKernel(
		StagingBuffer& assemblyBuff, uint32_t nSucceeded,
		compactKernelCbFn callback);
	bool startCollateKernel(
		StagingBuffer& assemblyBuff, StagingBuffer& collationBuff,
		collateKernelCbFn callback);

	void compactKernelComplete();
	void collateKernelComplete();
	bool stop();

public:
	// Get kernel execution durations in milliseconds
	std::chrono::milliseconds getCompactKernelDuration() const;
	std::chrono::milliseconds getCollateKernelDuration() const;

private:
	PcloudStimulusBuffer& parent;

	// OpenCL infrastructure
	cl_platform_id platform;
	cl_device_id device;
	cl_context context;
	cl_command_queue commandQueue;
	cl_program slotCompactorProgram;
	cl_program collateProgram;
	cl_kernel slotCompactorKernel;
	cl_kernel collateKernel;

	// OpenCL buffers
	cl_mem clAssemblyBuffer;
	cl_mem clCollationBuffer;

	// State tracking
	SpinLock shouldAcceptRequestsLock;
	bool shouldAcceptRequests;
	bool compactIsRunning;
	bool collateIsRunning;
	cl_event currentCompactKernelEvent;
	cl_event currentCollateKernelEvent;

	// Memory tracking
	void* assemblyBufferPtr;
	size_t assemblyBufferSize;
	void* collationBufferPtr;
	size_t collationBufferSize;
	// Mapped buffer pointers (for zero-copy synchronization)
	void* mappedAssemblyBuffer;
	void* mappedCollationBuffer;

	// Frame descriptor (cached from setup)
	std::shared_ptr<FrameAssemblyDesc> frameAssemblyDesc;

	// Callback storage
	compactKernelCbFn compactKernelCb;
	collateKernelCbFn collateKernelCb;

	// Timestamp tracking for kernel execution
	std::chrono::high_resolution_clock::time_point compactKernelStartTime;
	std::chrono::high_resolution_clock::time_point compactKernelEndTime;
	std::chrono::high_resolution_clock::time_point collateKernelStartTime;
	std::chrono::high_resolution_clock::time_point collateKernelEndTime;

	// Static callbacks for OpenCL events
	static void CL_CALLBACK compactKernelEventCallback(
		cl_event event, cl_int event_command_exec_status, void* user_data);
	static void CL_CALLBACK collateKernelEventCallback(
		cl_event event, cl_int event_command_exec_status, void* user_data);

	// Private helper methods
	bool compileAndPrepareKernel(
		const char* kernelSource, size_t kernelSourceLen,
		const char* kernelName, cl_program& program, cl_kernel& kernel);
	bool compileAndPrepareKernels();
	bool setupSlotCompactorsArgs(
		StagingBuffer& assemblyBuff, uint32_t nSucceeded);
	bool setupCollateDgramsArgs(StagingBuffer& assemblyBuff);

	// Generic buffer mapping/unmapping for zero-copy synchronization
	bool mapBuffer(
		cl_mem buffer, size_t size, cl_map_flags mapFlags, void*& mappedPtr);
	bool unmapBuffer(cl_mem buffer, void*& mappedPtr);

	// Wrapper functions for specific buffers
	bool mapAssemblyBuffer(cl_map_flags mapFlags = CL_MAP_READ);
	bool unmapAssemblyBuffer();
	bool mapCollationBuffer(cl_map_flags mapFlags = CL_MAP_READ);
	bool unmapCollationBuffer();

	// Forward declaration for continuation class
	class CompactCollateAndMeshFrameReq;

	// Unified kernel start function
	template<typename SetupArgsFn, typename ValidateBuffersFn>
	bool startKernel(
		cl_kernel kernel,
		cl_event* eventPtr,
		SetupArgsFn setupArgsFn,
		ValidateBuffersFn validateBuffersFn,
		size_t globalWorkSize,
		void (CL_CALLBACK *eventCallback)(cl_event, cl_int, void*),
		const char* kernelName,
		bool& isRunning)
	{
		if (isRunning)
		{
			std::cerr << __func__ << ": already running, call stop() first"
				<< std::endl;
			return false;
		}

		// Validate buffers
		validateBuffersFn();

		// Set up kernel arguments
		if (!setupArgsFn()) {
			return false;
		}

		// Enqueue kernel execution
		cl_int err = clEnqueueNDRangeKernel(
			commandQueue, kernel, 1, nullptr, &globalWorkSize, nullptr,
			0, nullptr, eventPtr);

		if (err != CL_SUCCESS)
		{
			std::cerr << __func__ << ": failed to enqueue " << kernelName
				<< " kernel: " << err << std::endl;
			return false;
		}

		// Set up callback using static member function
		err = clSetEventCallback(
			*eventPtr, CL_COMPLETE, eventCallback, this);

		if (err != CL_SUCCESS)
		{
			std::cerr << __func__ << ": failed to set event callback: " << err
				<< std::endl;
			clReleaseEvent(*eventPtr);
			*eventPtr = nullptr;
			return false;
		}

		// Force queue flush to ensure event processing and callback invocation
		err = clFlush(commandQueue);
		if (err != CL_SUCCESS)
		{
			std::cerr << __func__ << ": failed to flush queue: " << err
				<< std::endl;
			clReleaseEvent(*eventPtr);
			*eventPtr = nullptr;
			return false;
		}

		isRunning = true;
		return true;
	}
};

} // namespace stim_buff
} // namespace smo

#endif // _LIVOX_GEN1_OPENCL_COLLATING_AND_MESHING_ENGINE_H