#include "sky.h"
#include "IVideoDriver.h"
#include "ISceneManager.h"
#include "ICameraSceneNode.h"
#include "S3DVertex.h"
#include "utility.h" // MYMIN
#include "tile.h" // getTexturePath
#include "noise.h" // easeCurve
#include "main.h" // g_profiler
#include "profiler.h"

//! constructor
Sky::Sky(scene::ISceneNode* parent, scene::ISceneManager* mgr, s32 id):
		scene::ISceneNode(parent, mgr, id),
		m_first_update(true),
		m_brightness(0.5),
		m_cloud_brightness(0.5),
		m_bgcolor_bright_f(1,1,1,1),
		m_skycolor_bright_f(1,1,1,1),
		m_cloudcolor_bright_f(1,1,1,1)
{
	setAutomaticCulling(scene::EAC_OFF);
	Box.MaxEdge.set(0,0,0);
	Box.MinEdge.set(0,0,0);

	// create material

	video::SMaterial mat;
	mat.Lighting = false;
	mat.ZBuffer = video::ECFN_NEVER;
	mat.ZWriteEnable = false;
	mat.AntiAliasing=0;
	mat.TextureLayer[0].TextureWrapU = video::ETC_CLAMP_TO_EDGE;
	mat.TextureLayer[0].TextureWrapV = video::ETC_CLAMP_TO_EDGE;
	mat.BackfaceCulling = false;

	m_materials[0] = mat;

	m_materials[1] = mat;
	//m_materials[1].MaterialType = video::EMT_TRANSPARENT_VERTEX_ALPHA;
	m_materials[1].MaterialType = video::EMT_TRANSPARENT_ALPHA_CHANNEL;

	m_materials[2] = mat;
	m_materials[2].setTexture(0, mgr->getVideoDriver()->getTexture(
			getTexturePath("sunrisebg.png").c_str()));
	m_materials[2].MaterialType = video::EMT_TRANSPARENT_ALPHA_CHANNEL;
	//m_materials[2].MaterialType = video::EMT_TRANSPARENT_ADD_COLOR;

	for(u32 i=0; i<SKY_STAR_COUNT; i++){
		m_stars[i] = v3f(
			myrand_range(-10000,10000),
			myrand_range(-10000,10000),
			myrand_range(-10000,10000)
		);
		m_stars[i].normalize();
	}
}

void Sky::OnRegisterSceneNode()
{
	if (IsVisible)
		SceneManager->registerNodeForRendering(this, scene::ESNRP_SKY_BOX);

	scene::ISceneNode::OnRegisterSceneNode();
}

const core::aabbox3d<f32>& Sky::getBoundingBox() const
{
	return Box;
}

//! renders the node.
void Sky::render()
{
	video::IVideoDriver* driver = SceneManager->getVideoDriver();
	scene::ICameraSceneNode* camera = SceneManager->getActiveCamera();

	if (!camera || !driver)
		return;
	
	ScopeProfiler sp(g_profiler, "Sky::render()", SPT_AVG);

	// draw perspective skybox

	core::matrix4 translate(AbsoluteTransformation);
	translate.setTranslation(camera->getAbsolutePosition());

	// Draw the sky box between the near and far clip plane
	const f32 viewDistance = (camera->getNearValue() + camera->getFarValue()) * 0.5f;
	core::matrix4 scale;
	scale.setScale(core::vector3df(viewDistance, viewDistance, viewDistance));

	driver->setTransform(video::ETS_WORLD, translate * scale);
	
	if(m_sunlight_seen)
	{
		float sunsize = 0.07;
		video::SColorf suncolor_f(1, 1, 0, 1);
		suncolor_f.r = 1;
		suncolor_f.g = MYMAX(0.3, MYMIN(1.0, 0.7+m_time_brightness*(0.5)));
		suncolor_f.b = MYMAX(0.0, m_brightness*0.95);
		video::SColorf suncolor2_f(1, 1, 1, 1);
		suncolor_f.r = 1;
		suncolor_f.g = MYMAX(0.3, MYMIN(1.0, 0.85+m_time_brightness*(0.5)));
		suncolor_f.b = MYMAX(0.0, m_brightness);

		float moonsize = 0.04;
		video::SColorf mooncolor_f(0.50, 0.57, 0.65, 1);
		video::SColorf mooncolor2_f(0.85, 0.875, 0.9, 1);
		
		float nightlength = 0.41;
		float wn = nightlength / 2;
		float wicked_time_of_day = 0;
		if(m_time_of_day > wn && m_time_of_day < 1.0 - wn)
			wicked_time_of_day = (m_time_of_day - wn)/(1.0-wn*2)*0.5 + 0.25;
		else if(m_time_of_day < 0.5)
			wicked_time_of_day = m_time_of_day / wn * 0.25;
		else
			wicked_time_of_day = 1.0 - ((1.0-m_time_of_day) / wn * 0.25);
		/*std::cerr<<"time_of_day="<<m_time_of_day<<" -> "
				<<"wicked_time_of_day="<<wicked_time_of_day<<std::endl;*/

		video::SColor suncolor = suncolor_f.toSColor();
		video::SColor suncolor2 = suncolor2_f.toSColor();
		video::SColor mooncolor = mooncolor_f.toSColor();
		video::SColor mooncolor2 = mooncolor2_f.toSColor();

		const f32 t = 1.0f;
		const f32 o = 0.0f;
		static const u16 indices[4] = {0,1,2,3};
		video::S3DVertex vertices[4];

		driver->setMaterial(m_materials[2]);
		{
			float mid1 = 0.25;
			float mid = (wicked_time_of_day < 0.5 ? mid1 : (1.0 - mid1));
			float a_ = 1.0 - fabs(wicked_time_of_day - mid) * 35.0;
			float a = easeCurve(MYMAX(0, MYMIN(1, a_)));
			//std::cerr<<"a_="<<a_<<" a="<<a<<std::endl;
			video::SColor c(255,255,255,255);
			float y = -(1.0 - a) * 0.2;
			vertices[0] = video::S3DVertex(-1,-0.05+y,-1, 0,0,1, c, t, t);
			vertices[1] = video::S3DVertex( 1,-0.05+y,-1, 0,0,1, c, o, t);
			vertices[2] = video::S3DVertex( 1, 0.2+y,-1, 0,0,1, c, o, o);
			vertices[3] = video::S3DVertex(-1, 0.2+y,-1, 0,0,1, c, t, o);
			for(u32 i=0; i<4; i++){
				if(wicked_time_of_day < 0.5)
					// Switch from -Z (south) to +X (east)
					vertices[i].Pos.rotateXZBy(90);
				else
					// Switch from -Z (south) to -X (west)
					vertices[i].Pos.rotateXZBy(-90);
			}
			driver->drawIndexedTriangleFan(&vertices[0], 4, indices, 2);
		}

		driver->setMaterial(m_materials[1]);
		
		// Draw sun
		if(wicked_time_of_day > 0.15 && wicked_time_of_day < 0.85)
		{
			float d = sunsize * 1.7;
			video::SColor c = suncolor;
			c.setAlpha(0.05*255);
			vertices[0] = video::S3DVertex(-d,-d,-1, 0,0,1, c, t, t);
			vertices[1] = video::S3DVertex( d,-d,-1, 0,0,1, c, o, t);
			vertices[2] = video::S3DVertex( d, d,-1, 0,0,1, c, o, o);
			vertices[3] = video::S3DVertex(-d, d,-1, 0,0,1, c, t, o);
			for(u32 i=0; i<4; i++){
				// Switch from -Z (south) to +X (east)
				vertices[i].Pos.rotateXZBy(90);
				vertices[i].Pos.rotateXYBy(wicked_time_of_day * 360 - 90);
			}
			driver->drawIndexedTriangleFan(&vertices[0], 4, indices, 2);

			d = sunsize * 1.2;
			c = suncolor;
			c.setAlpha(0.15*255);
			vertices[0] = video::S3DVertex(-d,-d,-1, 0,0,1, c, t, t);
			vertices[1] = video::S3DVertex( d,-d,-1, 0,0,1, c, o, t);
			vertices[2] = video::S3DVertex( d, d,-1, 0,0,1, c, o, o);
			vertices[3] = video::S3DVertex(-d, d,-1, 0,0,1, c, t, o);
			for(u32 i=0; i<4; i++){
				// Switch from -Z (south) to +X (east)
				vertices[i].Pos.rotateXZBy(90);
				vertices[i].Pos.rotateXYBy(wicked_time_of_day * 360 - 90);
			}
			driver->drawIndexedTriangleFan(&vertices[0], 4, indices, 2);

			d = sunsize;
			vertices[0] = video::S3DVertex(-d,-d,-1, 0,0,1, suncolor, t, t);
			vertices[1] = video::S3DVertex( d,-d,-1, 0,0,1, suncolor, o, t);
			vertices[2] = video::S3DVertex( d, d,-1, 0,0,1, suncolor, o, o);
			vertices[3] = video::S3DVertex(-d, d,-1, 0,0,1, suncolor, t, o);
			for(u32 i=0; i<4; i++){
				// Switch from -Z (south) to +X (east)
				vertices[i].Pos.rotateXZBy(90);
				vertices[i].Pos.rotateXYBy(wicked_time_of_day * 360 - 90);
			}
			driver->drawIndexedTriangleFan(&vertices[0], 4, indices, 2);

			d = sunsize * 0.7;
			vertices[0] = video::S3DVertex(-d,-d,-1, 0,0,1, suncolor2, t, t);
			vertices[1] = video::S3DVertex( d,-d,-1, 0,0,1, suncolor2, o, t);
			vertices[2] = video::S3DVertex( d, d,-1, 0,0,1, suncolor2, o, o);
			vertices[3] = video::S3DVertex(-d, d,-1, 0,0,1, suncolor2, t, o);
			for(u32 i=0; i<4; i++){
				// Switch from -Z (south) to +X (east)
				vertices[i].Pos.rotateXZBy(90);
				vertices[i].Pos.rotateXYBy(wicked_time_of_day * 360 - 90);
			}
			driver->drawIndexedTriangleFan(&vertices[0], 4, indices, 2);
		}
		// Draw moon
		if(wicked_time_of_day < 0.3 || wicked_time_of_day > 0.7)
		{
			float d = moonsize * 1.9;
			video::SColor c = mooncolor;
			c.setAlpha(0.05*255);
			vertices[0] = video::S3DVertex(-d,-d,-1, 0,0,1, c, t, t);
			vertices[1] = video::S3DVertex( d,-d,-1, 0,0,1, c, o, t);
			vertices[2] = video::S3DVertex( d, d,-1, 0,0,1, c, o, o);
			vertices[3] = video::S3DVertex(-d, d,-1, 0,0,1, c, t, o);
			for(u32 i=0; i<4; i++){
				// Switch from -Z (south) to -X (west)
				vertices[i].Pos.rotateXZBy(-90);
				vertices[i].Pos.rotateXYBy(wicked_time_of_day * 360 - 90);
			}
			driver->drawIndexedTriangleFan(&vertices[0], 4, indices, 2);
			
			d = moonsize * 1.3;
			c = mooncolor;
			c.setAlpha(0.15*255);
			vertices[0] = video::S3DVertex(-d,-d,-1, 0,0,1, c, t, t);
			vertices[1] = video::S3DVertex( d,-d,-1, 0,0,1, c, o, t);
			vertices[2] = video::S3DVertex( d, d,-1, 0,0,1, c, o, o);
			vertices[3] = video::S3DVertex(-d, d,-1, 0,0,1, c, t, o);
			for(u32 i=0; i<4; i++){
				// Switch from -Z (south) to -X (west)
				vertices[i].Pos.rotateXZBy(-90);
				vertices[i].Pos.rotateXYBy(wicked_time_of_day * 360 - 90);
			}
			driver->drawIndexedTriangleFan(&vertices[0], 4, indices, 2);
			
			d = moonsize;
			vertices[0] = video::S3DVertex(-d,-d,-1, 0,0,1, mooncolor, t, t);
			vertices[1] = video::S3DVertex( d,-d,-1, 0,0,1, mooncolor, o, t);
			vertices[2] = video::S3DVertex( d, d,-1, 0,0,1, mooncolor, o, o);
			vertices[3] = video::S3DVertex(-d, d,-1, 0,0,1, mooncolor, t, o);
			for(u32 i=0; i<4; i++){
				// Switch from -Z (south) to -X (west)
				vertices[i].Pos.rotateXZBy(-90);
				vertices[i].Pos.rotateXYBy(wicked_time_of_day * 360 - 90);
			}
			driver->drawIndexedTriangleFan(&vertices[0], 4, indices, 2);
			
			float d2 = moonsize * 0.6;
			vertices[0] = video::S3DVertex(-d,-d,-1, 0,0,1, mooncolor2, t, t);
			vertices[1] = video::S3DVertex( d2,-d,-1, 0,0,1, mooncolor2, o, t);
			vertices[2] = video::S3DVertex( d2, d2,-1, 0,0,1, mooncolor2, o, o);
			vertices[3] = video::S3DVertex(-d, d2,-1, 0,0,1, mooncolor2, t, o);
			for(u32 i=0; i<4; i++){
				// Switch from -Z (south) to -X (west)
				vertices[i].Pos.rotateXZBy(-90);
				vertices[i].Pos.rotateXYBy(wicked_time_of_day * 360 - 90);
			}
			driver->drawIndexedTriangleFan(&vertices[0], 4, indices, 2);
		}
		// Stars
		do{
			float starbrightness = MYMAX(0, MYMIN(1,
					(0.285 - fabs(wicked_time_of_day < 0.5 ?
					wicked_time_of_day : (1.0 - wicked_time_of_day))) * 10));
			float f = starbrightness;
			video::SColor starcolor(255, f*120,f*120,f*120);
			if(starcolor.getBlue() < m_skycolor.getBlue())
				break;
			u16 indices[SKY_STAR_COUNT*4];
			video::S3DVertex vertices[SKY_STAR_COUNT*4];
			for(u32 i=0; i<SKY_STAR_COUNT; i++){
				indices[i*4+0] = i*4+0;
				indices[i*4+1] = i*4+1;
				indices[i*4+2] = i*4+2;
				indices[i*4+3] = i*4+3;
				v3f p = m_stars[i];
				core::CMatrix4<f32> a;
				float d = 0.005;
				a.buildRotateFromTo(v3f(0,1,0), v3f(d,1,0));
				v3f p1 = p;
				a.rotateVect(p1);
				a.buildRotateFromTo(v3f(0,1,0), v3f(d,1+d/2,d));
				v3f p2 = p;
				a.rotateVect(p2);
				a.buildRotateFromTo(v3f(0,1,0), v3f(0,1,d));
				v3f p3 = p;
				a.rotateVect(p3);
				p.rotateXYBy(wicked_time_of_day * 360 - 90);
				p1.rotateXYBy(wicked_time_of_day * 360 - 90);
				p2.rotateXYBy(wicked_time_of_day * 360 - 90);
				p3.rotateXYBy(wicked_time_of_day * 360 - 90);
				vertices[i*4+0].Pos = p;
				vertices[i*4+0].Color = starcolor;
				vertices[i*4+1].Pos = p1;
				vertices[i*4+1].Color = starcolor;
				vertices[i*4+2].Pos = p2;
				vertices[i*4+2].Color = starcolor;
				vertices[i*4+3].Pos = p3;
				vertices[i*4+3].Color = starcolor;
			}
			driver->drawVertexPrimitiveList(vertices, SKY_STAR_COUNT*4,
					indices, SKY_STAR_COUNT, video::EVT_STANDARD,
					scene::EPT_QUADS, video::EIT_16BIT);
		}while(0);
		
		for(u32 j=0; j<2; j++)
		{
			vertices[0] = video::S3DVertex(-1,-1.0,-1, 0,0,1, m_skycolor, t, t);
			vertices[1] = video::S3DVertex( 1,-1.0,-1, 0,0,1, m_skycolor, o, t);
			vertices[2] = video::S3DVertex( 1,-0.02,-1, 0,0,1, m_skycolor, o, o);
			vertices[3] = video::S3DVertex(-1,-0.02,-1, 0,0,1, m_skycolor, t, o);
			for(u32 i=0; i<4; i++){
				//if(wicked_time_of_day < 0.5)
				if(j==0)
					// Switch from -Z (south) to +X (east)
					vertices[i].Pos.rotateXZBy(90);
				else
					// Switch from -Z (south) to -X (west)
					vertices[i].Pos.rotateXZBy(-90);
			}
			driver->drawIndexedTriangleFan(&vertices[0], 4, indices, 2);
		}
	}
}

void Sky::update(float time_of_day, float time_brightness,
		float direct_brightness, bool sunlight_seen)
{
	// Stabilize initial brightness and color values by flooding updates
	if(m_first_update){
		/*dstream<<"First update with time_of_day="<<time_of_day
				<<" time_brightness="<<time_brightness
				<<" direct_brightness="<<direct_brightness
				<<" sunlight_seen="<<sunlight_seen<<std::endl;*/
		m_first_update = false;
		for(u32 i=0; i<100; i++){
			update(time_of_day, time_brightness, direct_brightness,
					sunlight_seen);
		}
		return;
	}

	m_time_of_day = time_of_day;
	m_time_brightness = time_brightness;
	m_sunlight_seen = sunlight_seen;
	
	bool is_dawn = (time_brightness >= 0.20 && time_brightness < 0.50);

	video::SColorf bgcolor_bright_normal_f(170./255,200./255,230./255, 1.0);
	video::SColorf bgcolor_bright_indoor_f(100./255,100./255,100./255, 1.0);
	//video::SColorf bgcolor_bright_dawn_f(0.666,200./255*0.7,230./255*0.5,1.0);
	//video::SColorf bgcolor_bright_dawn_f(0.666,0.549,0.220,1.0);
	//video::SColorf bgcolor_bright_dawn_f(0.666*1.2,0.549*1.0,0.220*1.0, 1.0);
	video::SColorf bgcolor_bright_dawn_f(0.666*1.2,0.549*1.0,0.220*1.2,1.0);

	video::SColorf skycolor_bright_normal_f =
			video::SColor(255, 140, 186, 250);
	video::SColorf skycolor_bright_dawn_f =
			video::SColor(255, 180, 186, 250);
	
	video::SColorf cloudcolor_bright_normal_f =
			video::SColor(255, 240,240,255);
	//video::SColorf cloudcolor_bright_dawn_f(1.0, 0.591, 0.4);
	//video::SColorf cloudcolor_bright_dawn_f(1.0, 0.65, 0.44);
	video::SColorf cloudcolor_bright_dawn_f(1.0, 0.7, 0.5);

	if(sunlight_seen){
		//m_brightness = m_brightness * 0.95 + direct_brightness * 0.05;
		m_brightness = m_brightness * 0.95 + time_brightness * 0.05;
	}
	else{
		if(direct_brightness < m_brightness)
			m_brightness = m_brightness * 0.95 + direct_brightness * 0.05;
		else
			m_brightness = m_brightness * 0.98 + direct_brightness * 0.02;
	}
	
	m_clouds_visible = true;
	float color_change_fraction = 0.98;
	if(sunlight_seen){
		if(is_dawn){
			m_bgcolor_bright_f = m_bgcolor_bright_f.getInterpolated(
					bgcolor_bright_dawn_f, color_change_fraction);
			m_skycolor_bright_f = m_skycolor_bright_f.getInterpolated(
					skycolor_bright_dawn_f, color_change_fraction);
			m_cloudcolor_bright_f = m_cloudcolor_bright_f.getInterpolated(
					cloudcolor_bright_dawn_f, color_change_fraction);
		} else {
			m_bgcolor_bright_f = m_bgcolor_bright_f.getInterpolated(
					bgcolor_bright_normal_f, color_change_fraction);
			m_skycolor_bright_f = m_skycolor_bright_f.getInterpolated(
					skycolor_bright_normal_f, color_change_fraction);
			m_cloudcolor_bright_f = m_cloudcolor_bright_f.getInterpolated(
					cloudcolor_bright_normal_f, color_change_fraction);
		}
	} else {
		m_bgcolor_bright_f = m_bgcolor_bright_f.getInterpolated(
				bgcolor_bright_indoor_f, color_change_fraction);
		m_cloudcolor_bright_f = m_cloudcolor_bright_f.getInterpolated(
				cloudcolor_bright_normal_f, color_change_fraction);
		m_skycolor_bright_f = m_skycolor_bright_f.getInterpolated(
				bgcolor_bright_indoor_f, color_change_fraction);
		m_clouds_visible = false;
	}
	video::SColor bgcolor_bright = m_bgcolor_bright_f.toSColor();
	m_bgcolor = video::SColor(
			255,
			bgcolor_bright.getRed() * m_brightness,
			bgcolor_bright.getGreen() * m_brightness,
			bgcolor_bright.getBlue() * m_brightness);
	
	video::SColor skycolor_bright = m_skycolor_bright_f.toSColor();
	m_skycolor = video::SColor(
			255,
			skycolor_bright.getRed() * m_brightness,
			skycolor_bright.getGreen() * m_brightness,
			skycolor_bright.getBlue() * m_brightness);
	
	float cloud_direct_brightness = 0;
	if(sunlight_seen){
		cloud_direct_brightness = time_brightness;
		if(time_brightness >= 0.2 && time_brightness < 0.7)
				cloud_direct_brightness *= 1.3;
	} else {
		cloud_direct_brightness = direct_brightness;
	}
	m_cloud_brightness = m_cloud_brightness * 0.95 +
			cloud_direct_brightness * (1.0 - 0.95);
	m_cloudcolor_f = video::SColorf(
			m_cloudcolor_bright_f.getRed() * m_cloud_brightness,
			m_cloudcolor_bright_f.getGreen() * m_cloud_brightness,
			m_cloudcolor_bright_f.getBlue() * m_cloud_brightness,
			1.0);

}