#pragma once
#ifndef REAL_BUILD
# include "externals.hh"
#endif


struct T_ProfilerSamples
{
	float sum;
	uint32_t nSamples;
};


struct T_Profiler
{
	static constexpr uint32_t Samples = 4;
	static constexpr uint32_t History = 4;
	static constexpr uint32_t Invalid = 0xffffffff;

	~T_Profiler( );

	void clear( );

	void startFrame( );
	void start( T_String const& section );
	void end( T_String const& section );
	void endFrame( );

	uint32_t sections( ) const noexcept
		{ return sections_.size( ); }

	T_String const& nameOf(
			const uint32_t section ) const
		{ return sections_[ section ]; }

	float durationOf( const uint32_t section ) const
		{ return secDurations_[ section ]; }
	float startOf( const uint32_t section ) const
		{ return secStarts_[ section ]; }

	void makeUI( );
	bool& uiEnabled( ) { return uiEnabled_; }

    private:
	using T_SamplesList_ = T_StaticArray< T_ProfilerSamples , History >;
	using T_Data_ = T_Array< T_SamplesList_ >;

	void extendGPUQueries( ) noexcept;
	static void addSample(
			T_SamplesList_& list ,
			uint64_t duration ) noexcept;

	uint32_t find( T_String const& section ) const;
	static float computeDuration(
			T_SamplesList_ const& list ) noexcept;

	uint32_t previous_;
	uint32_t current_;

	T_Array< T_String > sections_;
	T_Array< uint32_t > chain_;
	T_Array< uint32_t > parents_;
	T_Data_ samples_;
	T_Array< uint64_t > cpuStarts_;

	T_Array< float > secCPUDurations_;
	T_Array< float > secGPUDurations_;
	T_Array< float > secDurations_;
	T_Array< float > secStarts_;

	bool uiEnabled_ = false;
	T_Array< bool > displayed_;

	T_Array< GLuint > gpuQueries_{ T_Array< GLuint >( 64 ) };
	T_Data_ gpuSamples_;
};