#pragma once

#include "RuntimeStore.h"

#include <cstdint>
#include <mutex>
#include <string>
#include <vector>

struct RuntimeSnapshotVersions
{
	uint64_t renderStateVersion = 0;
	uint64_t parameterStateVersion = 0;
};

struct RuntimeRenderStateSnapshot
{
	RuntimeSnapshotVersions versions;
	unsigned outputWidth = 0;
	unsigned outputHeight = 0;
	std::vector<RuntimeRenderState> states;
};

class RuntimeSnapshotProvider
{
public:
	explicit RuntimeSnapshotProvider(RuntimeStore& runtimeStore);

	bool BuildLayerPassFragmentShaderSources(const std::string& layerId, std::vector<ShaderPassBuildSource>& passSources, std::string& error) const;
	unsigned GetMaxTemporalHistoryFrames() const;
	RuntimeSnapshotVersions GetVersions() const;
	void AdvanceFrame();
	RuntimeRenderStateSnapshot PublishRenderStateSnapshot(unsigned outputWidth, unsigned outputHeight) const;
	bool TryPublishRenderStateSnapshot(unsigned outputWidth, unsigned outputHeight, RuntimeRenderStateSnapshot& snapshot) const;
	bool TryRefreshPublishedSnapshotParameters(RuntimeRenderStateSnapshot& snapshot) const;
	void RefreshDynamicRenderStateFields(std::vector<RuntimeRenderState>& states) const;

private:
	bool TryGetPublishedRenderStateSnapshot(unsigned outputWidth, unsigned outputHeight,
		const RuntimeSnapshotVersions& versions, RuntimeRenderStateSnapshot& snapshot) const;
	void StorePublishedRenderStateSnapshot(const RuntimeRenderStateSnapshot& snapshot) const;
	static bool SnapshotMatches(const RuntimeRenderStateSnapshot& snapshot, unsigned outputWidth, unsigned outputHeight,
		const RuntimeSnapshotVersions& versions);

	RuntimeStore& mRuntimeStore;
	mutable std::mutex mPublishedSnapshotMutex;
	mutable bool mHasPublishedRenderStateSnapshot = false;
	mutable RuntimeRenderStateSnapshot mPublishedRenderStateSnapshot;
};