#pragma once
#include "sync.hh"
#include "opast.hh"

namespace ops {

using namespace ebcl;

enum E_OpType
{
	OP_END ,
	//
	OP_CALL ,
	OP_RET ,
	//
	OP_SKIP ,
	OP_COND_SKIP ,
	//
	OP_RES_STACK ,
	OP_PUSH ,
	OP_POP ,
	OP_DUP ,
	//
	OP_LOAD ,
	OP_SLOAD ,
	OP_CONST ,
	//
	OP_FP_LOAD ,
	OP_FP_STORE ,
	OP_FP_SLOAD ,
	OP_FP_SSTORE ,
	OP_FP_SSTORE_INT ,
	//
	OP_FP_CMP ,
	OP_FP_ADD ,
	OP_FP_SUB ,
	OP_FP_MUL ,
	OP_FP_DIV ,
	OP_FP_POW ,
	//
	OP_FP_NEG ,
	OP_FP_INV ,
	OP_FP_NOT ,
	OP_FP_SIN ,
	OP_FP_COS ,
	OP_FP_TAN ,
	OP_FP_SQRT ,
	OP_FP_EXP ,
	OP_FP_LN ,
	//
	OP_INIT_PIPELINE ,
	OP_INIT_PROGRAM ,
	OP_INIT_SAMPLER ,
	OP_INIT_TEXTURE ,
	OP_FB_ATTACH ,
	//
	OP_USE_FRAMEBUFFER ,
	OP_FB_TOGGLE ,
	OP_USE_PIPELINE ,
	OP_USE_PROGRAM ,
	OP_USE_TEXTURE ,
	OP_UNIFORMS ,
	OP_VIEWPORT ,
	//
	OP_FULLSCREEN ,
	OP_CLEAR ,
	//
	OP_UI_PENTER ,
	OP_UI_PEXIT ,
	OP_UI_INPUT_DFT ,
	OP_UI_ODBG ,
};

M_LSHIFT_OP( T_StringBuilder , E_OpType );
uint32_t ArgumentsFor( E_OpType op ) noexcept;
int32_t DeltaMainStack( E_OpType op ) noexcept;
int32_t DeltaFPUStack( E_OpType op ) noexcept;


struct T_Op
{
	static constexpr int MAX_ARGS = 2;

	E_OpType op;
	T_SRDLocation location;
	uint32_t args[ MAX_ARGS ];

	T_Op( const E_OpType op ,
			T_SRDLocation const& location ,
			const uint32_t arg0 = 0 ) noexcept
		: op( op ) , location( location ) ,
			args{ arg0 }
	{ }

	T_Op( const E_OpType op ,
			T_SRDLocation const& location ,
			std::initializer_list< uint32_t > a ) noexcept
		: op( op ) , location( location )
	{
		assert( a.size( ) <= MAX_ARGS );
		auto it = a.begin( );
		for ( auto i = 0u ; i < a.size( ) ; i ++ , ++it ) {
			args[ i ] = *it;
		}
	}
};
M_LSHIFT_OP( T_StringBuilder , T_Op const& );


union T_OpValue
{
	int32_t i;
	uint32_t u;
	float f;
};

struct T_OpProgram
{
	T_MultiArray< T_Op > ops;		// All operations
	uint32_t init ,				// Index of initialisation function
		 frame;				// Index of frame rendering function

	T_Array< T_OpValue > constants;		// Constants values
	uint32_t nVariables{ 0 };		// Amount of variables

	T_Array< T_String > inputs;		// Input definitions

	uint32_t nPrograms{ 0 } ,		// Amount of programs
		 nFramebuffers{ 0 } ,		// Amount of framebuffers
		 nPipelines{ 0 } ,		// Amount of pipelines
		 nSamplers{ 0 } ,		// Amount of samplers
		 nTextures{ 0 };		// Amount of textures
	T_Array< T_String > progNames;		// GLSL program files

	T_Array< T_String > uiStrings;		// UI strings for profiling, etc.
};
using P_OpProgram = T_OwnPtr< T_OpProgram >;

struct T_OpContext
{
	T_OpProgram& program;		// The program

	uint32_t instrPtr;		// Instruction pointer
	bool aborted;			// Did the program fail?

	T_Array< T_OpValue > values;	// VM data
	T_Array< T_OpValue > stack;	// Main VM stack

	double x87stack[ 8 ];		// x87 FPU emulation stack
	int x87sp;			// x87 FPU emulation stack pointer
};

class X_OpFailure : public std::exception
{
    public:
	X_OpFailure( ) = delete;
	DEF_COPY( X_OpFailure );
	DEF_MOVE( X_OpFailure );

	X_OpFailure( T_Op const& op ,
		T_String error ) noexcept;

	T_Op const& op( ) const noexcept
		{ return *op_; }
	T_String const& error( ) const noexcept
		{ return error_; }

	char const* what( ) const noexcept override;

    private:
	T_Op const* op_;
	T_String error_;
	T_String fullMessage_;
};

class T_Compiler : public A_PrivateImplementation
{
    public:
	T_Compiler( ) noexcept;

	P_OpProgram compile(
			opast::T_ParserOutput const& input ) noexcept;
};

} // namespace ops


/*= FIXME OLD VERSION BELOW ====================================================*/

namespace cops {

	struct T_Program;

	struct T_Context
	{
		T_Program const* program;

		T_KeyValueTable< T_String , float > vars;

		T_Array< float > opStack;

		T_Context& store(
			T_String const& name ,
			const float value );
	};

	class X_OpFailure : public std::exception
	{
	    public:
		X_OpFailure( ) = delete;
		DEF_COPY( X_OpFailure );
		DEF_MOVE( X_OpFailure );

		X_OpFailure(
			T_String const& source ,
			uint32_t line ,
			T_String&& error ) noexcept;

		T_String const& source( ) const noexcept
			{ return source_; }
		uint32_t line( ) const noexcept
			{ return line_; }
		T_String const& error( ) const noexcept
			{ return error_; }

		char const* what( ) const noexcept override;

	    private:
		T_String source_;
		uint32_t line_;
		T_String error_;
		T_String fullMessage_;
	};

	/*--------------------------------------------------------------------*/

	enum E_Op
	{
		OP_LOAD_CONSTANT ,
		OP_LOAD_VARIABLE ,
		OP_LOAD_INPUT ,
		OP_STORE_VARIABLE ,
		//
		OP_ADD , OP_MUL ,
		OP_NEG , OP_INV ,
		//
		OP_DUP , OP_XCHG ,
		//
		OP_SET_UNIFORM ,
		OP_USE_PIPELINE ,
		OP_USE_TEXTURE ,
		OP_USE_FRAMEBUFFER ,
		OP_SET_VIEWPORT ,
		//
		OP_CLEAR ,
		OP_FULLSCREEN ,
		//
		OP_CALL
	};

	struct T_Op
	{
		explicit T_Op(
			const E_Op op );
		virtual ~T_Op( ) = 0;

		E_Op op( ) const noexcept
			{ return op_; }

		virtual void execute(
			T_Context& ctx ) const = 0;

		T_String source{};
		uint32_t line{0};

	    protected:
		X_OpFailure error(
			ebcl::T_StringBuilder& message ) const noexcept;
		X_OpFailure error(
			T_String const& message ) const noexcept;

	    private:
		E_Op op_;
	};
	using P_Op = T_OwnPtr< T_Op >;
	using T_Operations = T_Array< P_Op >;

	template< typename T >
	inline T_Operations& operator <<(
			T_Operations& ops ,
			T&& item )
	{
		ops.add( NewOwned< T >( std::move( item ) ) );
		return ops;
	}

	void Execute(
		T_Operations const& operations ,
		T_Context& context );

	/*--------------------------------------------------------------------*/

	struct T_Function
	{
		T_String name;
		uint32_t arguments;
		T_Operations operations;

		T_Function( T_String const& name ,
				const uint32_t arguments )
			: name( name ) , arguments( arguments )
		{ }
		DEF_COPY( T_Function );
		DEF_MOVE( T_Function );
	};

	struct T_Program
	{
		T_ObjectTable< T_String , T_Function > functions;
		T_Operations main;

		T_Program( )
			: functions( []( T_Function const& f ) -> T_String {
						return f.name;
					} )
		{ }

		T_Operations& function(
				T_String const& name ,
				const uint32_t args );

		void execute( T_Context& context )
		{
			context.program = this;
			Execute( main , context );
		}
	};

	/*====================================================================*/

	struct OPLoadConstant : public T_Op
	{
		explicit OPLoadConstant(
			const float constant );
		void execute(
			T_Context& ctx ) const override;
		float constant;
	};

	struct OPLoadVariable : public T_Op
	{
		explicit OPLoadVariable(
			T_String const& variable );
		void execute(
			T_Context& ctx ) const override;
		T_String variable;
	};

	struct OPLoadInput : public T_Op
	{
		explicit OPLoadInput(
			T_String const& input );
		void execute(
			T_Context& ctx ) const override;
		T_String input;
	};

	struct OPStoreVariable : public T_Op
	{
		explicit OPStoreVariable(
			T_String const& variable );
		void execute(
			T_Context& ctx ) const override;
		T_String variable;
	};

	/*--------------------------------------------------------------------*/

	struct OPAdd : public T_Op
	{
		OPAdd( ) : T_Op( OP_ADD ) {}
		void execute(
			T_Context& ctx ) const override;
	};

	struct OPMul : public T_Op
	{
		OPMul( ) : T_Op( OP_MUL ) {}
		void execute(
			T_Context& ctx ) const override;
	};

	struct OPNeg : public T_Op
	{
		OPNeg( ) : T_Op( OP_NEG ) {}
		void execute(
			T_Context& ctx ) const override;
	};

	struct OPInv : public T_Op
	{
		OPInv( ) : T_Op( OP_INV ) {}
		void execute(
			T_Context& ctx ) const override;
	};

	/*--------------------------------------------------------------------*/

	struct OPDup : public T_Op
	{
		explicit OPDup( uint32_t stackIndex = 0 );
		void execute(
			T_Context& ctx ) const override;
		uint32_t stackIndex;
	};

	struct OPXchg : public T_Op
	{
		explicit OPXchg( uint32_t stackIndex = 1 );
		void execute(
			T_Context& ctx ) const override;
		uint32_t stackIndex;
	};

	/*--------------------------------------------------------------------*/

	struct OPSetUniform : public T_Op
	{
		OPSetUniform(
			const uint32_t count ,
			const bool integer );
		void execute(
			T_Context& ctx ) const override;

		uint32_t count;
		bool integer;
	};

	struct OPUsePipeline : public T_Op
	{
		explicit OPUsePipeline(
			const uint32_t index );
		void execute(
			T_Context& ctx ) const override;

		uint32_t pipeline;
	};

	struct OPUseTexture : public T_Op
	{
		OPUseTexture(
			const uint32_t binding ,
			const uint32_t texture ,
			const uint32_t sampler = 0 );
		void execute(
			T_Context& ctx ) const override;

		uint32_t binding;
		uint32_t texture;
		uint32_t sampler;
	};

	struct OPUseFramebuffer : public T_Op
	{
		explicit OPUseFramebuffer(
			const uint32_t framebuffer );
		void execute(
			T_Context& ctx ) const override;

		uint32_t framebuffer;
	};

	struct OPSetViewport : public T_Op
	{
		OPSetViewport( ) : T_Op( OP_SET_VIEWPORT ) { }
		void execute(
			T_Context& ctx ) const override;
	};

	/*--------------------------------------------------------------------*/

	struct OPClear : public T_Op
	{
		OPClear( ) : T_Op( OP_CLEAR ) { }
		void execute(
			T_Context& ctx ) const override;
	};

	struct OPFullscreen : public T_Op
	{
		OPFullscreen( ) : T_Op( OP_FULLSCREEN ) { }
		void execute(
			T_Context& ctx ) const override;
	};

	/*--------------------------------------------------------------------*/

	struct OPCall : public T_Op
	{
		explicit OPCall(
			T_String const& function );
		void execute(
			T_Context& ctx ) const override;

		T_String function;
	};

} // namespace cops