#include "behavior.h"

#include <uf/utils/renderer/renderer.h>

#include <uf/utils/math/transform.h>
#include <uf/utils/math/physics.h>
#include <uf/utils/camera/camera.h>

namespace {
	struct {
		size_t current = 0;
		std::vector<uf::Object*> lights;
	} roundRobin;
}

UF_BEHAVIOR_REGISTER_CPP(ext::LightBehavior)
#define this (&self)
void ext::LightBehavior::initialize( uf::Object& self ) {
	auto& metadata = this->getComponent<ext::LightBehavior::Metadata>();
	auto& metadataJson = this->getComponent<uf::Serializer>();
	auto& transform = this->getComponent<pod::Transform<>>();
	auto& camera = this->getComponent<uf::Camera>();
	auto& scene = uf::scene::getCurrentScene();
	auto& controller = scene.getController();
	auto& sceneMetadata = scene.getComponent<uf::Serializer>();

	if ( !sceneMetadata["system"]["lights"]["round robin hook bound"].as<bool>() ) {
		sceneMetadata["system"]["lights"]["round robin hook bound"] = true;
		scene.addHook("game:Frame.Start", [&]( const ext::json::Value& payload ){
			if ( ++::roundRobin.current >= ::roundRobin.lights.size() ) ::roundRobin.current = 0;
		});
	}
/*
	if ( !metadataJson["light"]["bias"]["shader"].is<float>() ) {
		metadataJson["light"]["bias"]["shader"] = 0.000000005f;
	}
*/
	if ( !metadataJson["light"]["bias"]["constant"].is<float>() ) {
		metadataJson["light"]["bias"]["constant"] = 0.00005f;
	}
	if ( !metadataJson["light"]["type"].is<std::string>() ) {
		metadataJson["light"]["type"] = "point";
	}
	if ( !ext::json::isArray( metadataJson["light"]["color"] ) ) {
		metadataJson["light"]["color"][0] = 1; //metadataJson["light"]["color"]["random"].as<bool>() ? (rand() % 100) / 100.0 : 1;
		metadataJson["light"]["color"][1] = 1; //metadataJson["light"]["color"]["random"].as<bool>() ? (rand() % 100) / 100.0 : 1;
		metadataJson["light"]["color"][2] = 1; //metadataJson["light"]["color"]["random"].as<bool>() ? (rand() % 100) / 100.0 : 1;
	}
#if UF_USE_OPENGL
	metadataJson["light"]["shadows"] = false;
#endif
	if ( !sceneMetadata["system"]["config"]["engine"]["scenes"]["lights"]["shadows"].as<bool>() ) {
		metadataJson["light"]["shadows"] = false;
	}
	if ( metadataJson["light"]["shadows"].as<bool>() ) {
		auto& cameraTransform = camera.getTransform();
		cameraTransform.reference = &transform;
		camera.setStereoscopic(false);
		if ( ext::json::isArray( metadataJson["light"]["radius"] ) ) {
			auto bounds = camera.getBounds();
			bounds.x = metadataJson["light"]["radius"][0].as<float>();
			bounds.y = metadataJson["light"]["radius"][1].as<float>();
			camera.setBounds(bounds);
		}
		if ( ext::json::isArray( metadataJson["light"]["resolution"] ) ) {
			camera.setSize( uf::vector::decode( metadataJson["light"]["resolution"], pod::Vector2ui{ uf::renderer::settings::width, uf::renderer::settings::height } ) );
		} else if ( metadataJson["light"]["resolution"].is<float>() ) {
			size_t size = metadataJson["light"]["resolution"].as<size_t>();
			camera.setSize( {size, size} );
		} else {
			camera.setSize( pod::Vector2ui{ uf::renderer::settings::width, uf::renderer::settings::height } );
		}
		
		::roundRobin.lights.emplace_back(this);

		auto& renderMode = this->getComponent<uf::renderer::RenderTargetRenderMode>();
		renderMode.metadata["type"] = "depth";
		renderMode.metadata["depth bias"] = metadataJson["light"]["bias"];
		renderMode.metadata["renderMode"] = metadataJson["renderMode"];

		if ( metadataJson["light"]["type"].as<std::string>() == "point" ) {
			metadataJson["light"]["fov"] = 90.0f;
			renderMode.metadata["subpasses"] = 6;
		}
		if ( metadataJson["light"]["fov"].is<float>() ) {
			camera.setFov( metadataJson["light"]["fov"].as<float>() );
		}
		camera.updateView();
		camera.updateProjection();
		
		std::string name = "RT:" + std::to_string((int) this->getUid());
		uf::renderer::addRenderMode( &renderMode, name );
		renderMode.blitter.process = false;
		auto& cameraSize = camera.getSize();
		renderMode.width = cameraSize.x;
		renderMode.height = cameraSize.y;
	//	UF_DEBUG_MSG(this->getName() << ": " << renderMode.metadata << " | " << metadataJson["light"]);
	}

	metadata.serialize = [&](){
		metadataJson["light"]["color"] = uf::vector::encode( metadata.color );
		metadataJson["light"]["power"] = metadata.power;
		metadataJson["light"]["bias"]["shader"] = metadata.bias;
		metadataJson["light"]["shadows"] = metadata.shadows;
		metadataJson["system"]["renderer"]["mode"] = metadata.renderer.mode;
		metadataJson["light"]["external update"] = metadata.renderer.external;
		metadataJson["system"]["renderer"]["timer"] = metadata.renderer.limiter;
		switch ( metadata.type ) {
			case 0: metadataJson["light"]["type"] = "point"; break;
			case 1: metadataJson["light"]["type"] = "spot"; break;
			case 2: metadataJson["light"]["type"] = "spot"; break;
		}
	};
	metadata.deserialize = [&](){
		metadata.color = uf::vector::decode( metadataJson["light"]["color"], pod::Vector3f{1,1,1} );
		metadata.power = metadataJson["light"]["power"].as<float>();
		metadata.bias = metadataJson["light"]["bias"]["shader"].as<float>();
		metadata.shadows = metadataJson["light"]["shadows"].as<bool>();
		metadata.renderer.mode = metadataJson["system"]["renderer"]["mode"].as<std::string>();
		metadata.renderer.rendered = false;
		metadata.renderer.external = metadataJson["light"]["external update"].as<bool>();
		metadata.renderer.limiter = metadataJson["system"]["renderer"]["timer"].as<float>();
		if ( metadataJson["light"]["type"].is<size_t>() ) {
			metadata.type = metadataJson["light"]["type"].as<size_t>();
		} else if ( metadataJson["light"]["type"].is<std::string>() ) {
			std::string lightType = metadataJson["light"]["type"].as<std::string>();
			if ( lightType == "point" ) metadata.type = 0;
			else if ( lightType == "spot" ) metadata.type = 1;
		}
	};
	this->addHook( "object:UpdateMetadata.%UID%", metadata.deserialize);
	metadata.deserialize();
}
void ext::LightBehavior::tick( uf::Object& self ) {
#if !UF_ENV_DREAMCAST
	auto& metadata = this->getComponent<ext::LightBehavior::Metadata>();
	auto& metadataJson = this->getComponent<uf::Serializer>();
	if ( this->hasComponent<uf::renderer::RenderTargetRenderMode>() ) {
		auto& renderMode = this->getComponent<uf::renderer::RenderTargetRenderMode>();
		renderMode.setTarget("");
	}
#if UF_ENTITY_METADATA_USE_JSON
	metadata.deserialize();
#else
	if ( !metadata.color ) metadata.color = uf::vector::decode( metadataJson["light"]["color"], pod::Vector3f{1,1,1} );
	if ( !metadata.power ) metadata.power = metadataJson["light"]["power"].as<float>();
	if ( !metadata.bias ) metadata.bias = metadataJson["light"]["bias"]["shader"].as<float>();
	if ( !metadata.shadows ) metadata.shadows = metadataJson["light"]["shadows"].as<bool>();
	if (  metadata.renderer.mode == "" ) metadata.renderer.mode = metadataJson["system"]["renderer"]["mode"].as<std::string>();
	if ( !metadata.renderer.external ) metadata.renderer.external = metadataJson["light"]["external update"].as<bool>();
	if ( !metadata.renderer.limiter ) metadata.renderer.limiter = metadataJson["system"]["renderer"]["timer"].as<float>();
	if ( !metadata.type ) {
		if ( metadataJson["light"]["type"].is<size_t>() ) {
			metadata.type = metadataJson["light"]["type"].as<size_t>();
		} else if ( metadataJson["light"]["type"].is<std::string>() ) {
			std::string lightType = metadataJson["light"]["type"].as<std::string>();
			if ( lightType == "point" ) metadata.type = 1;
			else if ( lightType == "spot" ) metadata.type = 2;
		}
		if ( metadataJson["light"]["dynamic"].as<bool>() ) metadata.type = -metadata.type;
	}
#endif
#if 0
	// light fade action
	if ( ext::json::isObject( metadataJson["light"]["fade"] ) ) {
		if ( ext::json::isNull( metadataJson["light"]["backup"]["power"] ) ) {
			metadataJson["light"]["backup"]["power"] = metadataJson["light"]["power"];
		}
		if ( ext::json::isNull( metadataJson["light"]["backup"]["color"] ) ) {
			metadataJson["light"]["backup"]["color"] = metadataJson["light"]["color"];
		}
		// fade towards
		int direction = metadataJson["light"]["fade"]["increment"].as<bool>() ? 1 : -1;
		metadataJson["light"]["fade"]["timer"] = metadataJson["light"]["fade"]["timer"].as<float>() + metadataJson["light"]["fade"]["rate"].as<float>() * uf::physics::time::delta * direction;

		// 0 .. delta .. 1 .. (1 + timeout * 0.5)
		if ( direction == 1 && metadataJson["light"]["fade"]["timer"].as<float>() >= 0.5f * metadataJson["light"]["fade"]["timeout"].as<float>() + 1.0f ) {
			metadataJson["light"]["fade"]["increment"] = false;
		} else if ( direction == -1 && metadataJson["light"]["fade"]["timer"].as<float>() <= -0.5f * metadataJson["light"]["fade"]["timeout"].as<float>() ) {
			metadataJson["light"]["fade"]["increment"] = true;
		}
		{
			float delta = metadataJson["light"]["fade"]["timer"].as<float>();
			delta = std::clamp( delta, 0.f, 1.f );
			if ( metadataJson["light"]["fade"]["power"].is<double>() ) {
				metadataJson["light"]["power"] = uf::math::lerp( metadataJson["light"]["backup"]["power"].as<float>(), metadataJson["light"]["fade"]["power"].as<float>(), delta );
			}
			if ( ext::json::isArray( metadataJson["light"]["fade"]["color"] ) ) {
				pod::Vector3f fadeColor; {
					fadeColor.x = metadataJson["light"]["fade"]["color"][0].as<float>();
					fadeColor.y = metadataJson["light"]["fade"]["color"][1].as<float>();
					fadeColor.z = metadataJson["light"]["fade"]["color"][2].as<float>();
				}
				pod::Vector3f origColor; {
					origColor.x = metadataJson["light"]["backup"]["color"][0].as<float>();
					origColor.y = metadataJson["light"]["backup"]["color"][1].as<float>();
					origColor.z = metadataJson["light"]["backup"]["color"][2].as<float>();
				}
				pod::Vector3f color = uf::vector::lerp( origColor, fadeColor, delta );

				metadataJson["light"]["color"][0] = color[0];
				metadataJson["light"]["color"][1] = color[1];
				metadataJson["light"]["color"][2] = color[2];
			}
		}
	}
	// light flicker action
	if ( ext::json::isObject( metadataJson["light"]["flicker"] ) ) {
		float r = (rand() % 100) / 100.0;
		float rate = metadataJson["light"]["flicker"]["rate"].as<float>();
		if ( ext::json::isNull( metadataJson["light"]["backup"]["power"] ) ) {
			metadataJson["light"]["backup"]["power"] = metadataJson["light"]["power"];
		}
		metadataJson["light"]["flicker"]["timer"] = metadataJson["light"]["flicker"]["timer"].as<float>() + uf::physics::time::delta;
		if ( metadataJson["light"]["flicker"]["timer"].as<float>() >= metadataJson["light"]["flicker"]["timeout"].as<float>() ) {
			metadataJson["light"]["flicker"]["timer"] = 0;
			metadataJson["light"]["power"] = (r > rate) ? metadataJson["light"]["flicker"]["power"].as<float>() : metadataJson["light"]["backup"]["power"].as<float>();
		}
	}
#endif
	// limit updating our shadow map
	if ( this->hasComponent<uf::renderer::RenderTargetRenderMode>() ) {
		// skip if we're handling the camera view matrix position ourselves
		if ( !metadata.renderer.external ) {
			auto& camera = this->getComponent<uf::Camera>();
			// omni light
			if ( metadata.shadows && std::abs(metadata.type) == 1 ) {
				auto transform = camera.getTransform();
				std::vector<pod::Quaternion<>> rotations = {
					uf::quaternion::axisAngle( { 0, 1, 0 }, 0 * 1.57079633 ),
					uf::quaternion::axisAngle( { 0, 1, 0 }, 1 * 1.57079633 ),
					uf::quaternion::axisAngle( { 0, 1, 0 }, 2 * 1.57079633 ),
					uf::quaternion::axisAngle( { 0, 1, 0 }, 3 * 1.57079633 ),
					
					uf::quaternion::axisAngle( { 1, 0, 0 }, 1 * 1.57079633 ),
					uf::quaternion::axisAngle( { 1, 0, 0 }, 3 * 1.57079633 ),
				};
				for ( size_t i = 0; i < rotations.size(); ++i ) {
					auto transform = camera.getTransform();
					transform.orientation = rotations[i];
					camera.setView( uf::matrix::inverse( uf::transform::model( transform, false ) ), i );
				}
			} else {
				camera.updateView();
			}
		}
		bool execute = true;
		// enable renderer every X seconds
		if ( metadata.renderer.limiter > 0 ) {
			if ( metadata.renderer.timer > metadata.renderer.limiter ) {
				metadata.renderer.timer = 0;
				execute = true;
			} else {
				metadata.renderer.timer = metadata.renderer.timer + uf::physics::time::delta;
				execute = false;
			}
		} else {
			// round robin, enable if it's the light's current turn
			if ( metadata.renderer.mode == "round robin" ) {
				if ( ::roundRobin.current < ::roundRobin.lights.size() ) execute = ::roundRobin.lights[::roundRobin.current] == this;
			// render only if the light is used
			} else if ( metadata.renderer.mode == "occlusion" ) {
				execute = metadata.renderer.rendered;
			// light baking, but sadly re-bakes every time the command buffer is recorded
			} else if ( metadata.renderer.mode == "once" ) {
				execute = !metadata.renderer.rendered;
				metadata.renderer.rendered = true;
			}
		}
		auto& renderMode = this->getComponent<uf::renderer::RenderTargetRenderMode>();
		renderMode.execute = execute;
	}
#if UF_ENTITY_METADATA_USE_JSON
	metadata.serialize();
#endif
#endif
}
void ext::LightBehavior::render( uf::Object& self ){

}
void ext::LightBehavior::destroy( uf::Object& self ){
	if ( this->hasComponent<uf::renderer::RenderTargetRenderMode>() ) {
		auto& renderMode = this->getComponent<uf::renderer::RenderTargetRenderMode>();
		uf::renderer::removeRenderMode( &renderMode, false );
		this->deleteComponent<uf::renderer::RenderTargetRenderMode>();
	}

	::roundRobin.lights.erase(std::remove(::roundRobin.lights.begin(), ::roundRobin.lights.end(), this), ::roundRobin.lights.end());
	::roundRobin.current = 0;
}
#undef this