#include "externals.hh"
#include "dof.hh"
#include "profiling.hh"
#include "globals.hh"

namespace {
	static const std::string Name_( "DoF" );
}

#define PSTART() T_Profiler::Profiler.start( Name_ )
#define PEND() do { glFinish( ); T_Profiler::Profiler.end( Name_ ); } while ( 0 )


T_DoFPass::T_DoFPass(
		__rw__ T_Texture& imageInput ,
		__rw__ T_Texture& depthInput )
	: imageInput_( imageInput ) , depthInput_( depthInput ) ,
		txPass1_( imageInput.width( ) , imageInput.height( ) ,
				E_TexType::RGB16F ) ,
		txOutput_( imageInput.width( ) , imageInput.height( ) ,
				E_TexType::RGB16F ) ,
		rtPass1_( T_RendertargetSetup( ).add( txPass1_ ).create( ) ) ,
		rtPass2_( T_RendertargetSetup( ).add( txOutput_ ).create( ) ) ,
		filterParams_{ 15 , 25 , 100 , 16 } ,
		nSamples_( 16 )
{
	txPass1_.wrap( E_TexWrap::CLAMP_EDGE );

	spPass1_ = Globals::Shaders( ).pipeline({
			"fullscreen.v.glsl" , "dof-pass1.f.glsl" });
	spPass2_ = Globals::Shaders( ).pipeline({
			"fullscreen.v.glsl" , "dof-pass2.f.glsl" });
}

void T_DoFPass::render( )
{
	PSTART( );
	enum {
		U_INPUT		= 0 ,
		U_DEPTH		= 1 ,
		U_PARAMS	= 2 ,
		U_SAMPLES	= 3 ,
		U_RES_TIME	= 4
	};

	auto& tm( Globals::Textures( ) );
	rtPass1_.activate( );
	if ( spPass1_.valid( ) ) {
		const auto id( spPass1_.program( E_ShaderType::FRAGMENT ) );
		spPass1_.enable( );
		glProgramUniform1i( id , U_INPUT , 0 );
		glProgramUniform1i( id , U_DEPTH , 1 );
		glProgramUniform4fv( id , U_PARAMS , 1 , filterParams_ );
		glProgramUniform1f( id , U_SAMPLES , nSamples_ );
		glProgramUniform3f( id , U_RES_TIME , imageInput_.width( ) ,
				imageInput_.height( ) ,
				0 );

		tm.bind( 0 , imageInput_ , *tm.sampler( "linear-edge" ) );
		tm.bind( 1 , depthInput_ , *tm.sampler( "linear-edge" ) );

		glDrawArrays( GL_TRIANGLE_STRIP , 0 , 4 );
	}
	rtPass2_.activate( );
	if ( spPass2_.valid( ) ) {
		const auto id( spPass2_.program( E_ShaderType::FRAGMENT ) );
		spPass2_.enable( );
		glProgramUniform1i( id , U_INPUT , 0 );
		glProgramUniform1i( id , U_DEPTH , 1 );
		glProgramUniform4fv( id , U_PARAMS , 1 , filterParams_ );
		glProgramUniform1f( id , U_SAMPLES , nSamples_ );
		glProgramUniform3f( id , U_RES_TIME ,
				imageInput_.width( ) ,
				imageInput_.height( ) ,
				0 );

		tm.bind( 0 , txPass1_ , *tm.sampler( "linear-edge" ) );

		glDrawArrays( GL_TRIANGLE_STRIP , 0 , 4 );
	}
	PEND( );
}

void T_DoFPass::makeUI( )
{
	if ( !ImGui::CollapsingHeader( "Depth of field" ) ) {
		return;
	}

	ImGui::DragFloat( "Sharp distance" , filterParams_ , .25 , 0.25 , 1000 );
	ImGui::DragFloat( "Sharp range" , &filterParams_[ 1 ] , .1 , 0.1 , 100 );
	ImGui::DragFloat( "Blur falloff" , &filterParams_[ 2 ] , .5 , 0.5 , 1000 );
	ImGui::DragFloat( "Max blur" , &filterParams_[ 3 ] , .1 , .1 , 100 );

	ImGui::DragInt( "Samples" , &nSamples_ , .2 , 1 , 32 );
}