#include "ViewerWidget.hpp"
#include <data/Model.hpp>
#include <render/GameRenderer.hpp>
#include <render/OpenGLRenderer.hpp>
#include <glm/gtc/type_ptr.hpp>
#include <QMouseEvent>
#include <objects/GameObject.hpp>
#include <engine/Animator.hpp>
#include <data/Skeleton.hpp>
#include <QFileDialog>
#include <algorithm>

#include <objects/InstanceObject.hpp>
#include <objects/CharacterObject.hpp>
#include <objects/VehicleObject.hpp>


ViewerWidget::ViewerWidget(QWidget* parent, const QGLWidget* shareWidget, Qt::WindowFlags f)
	: QGLWidget(parent, shareWidget, f)
	, gworld(nullptr)
	, activeModel(nullptr)
	, selectedFrame(nullptr)
	, dummyObject(nullptr)
	, currentObjectID(0)
	, _lastModel(nullptr)
	, canimation(nullptr)
	, viewDistance(1.f)
	, dragging(false)
	, moveFast(false)
	, _frameWidgetDraw(nullptr)
	, _frameWidgetGeom(nullptr)
{
	setFocusPolicy(Qt::StrongFocus);
}

struct WidgetVertex {
	float x, y, z;
	static const AttributeList vertex_attributes() {
		return {
			{ATRS_Position, 3, sizeof(WidgetVertex),  0ul}
		};
	}
};

std::vector<WidgetVertex> widgetVerts = {
	{-.5f, 0.f, 0.f},
	{ .5f, 0.f, 0.f},
	{ 0.f,-.5f, 0.f},
	{ 0.f, .5f, 0.f},
	{ 0.f, 0.f,-.5f},
	{ 0.f, 0.f, .5f}
};

void ViewerWidget::initializeGL()
{
	QGLWidget::initializeGL();
	timer.setInterval(16);
	connect(&timer, SIGNAL(timeout()), SLOT(updateGL()));
	timer.start();

	_frameWidgetDraw = new DrawBuffer;
	_frameWidgetDraw->setFaceType(GL_LINES);
	_frameWidgetGeom = new GeometryBuffer;
	_frameWidgetGeom->uploadVertices(widgetVerts);
	_frameWidgetDraw->addGeometry(_frameWidgetGeom);

	glGenTextures(1, &whiteTex);
	glBindTexture(GL_TEXTURE_2D, whiteTex);
	GLuint tex = 0xFFFFFFFF;
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 1, 1, 0, GL_RGB, GL_UNSIGNED_BYTE, &tex);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
}

void ViewerWidget::resizeGL(int w, int h)
{
	QGLWidget::resizeGL(w, h);
	glViewport(0, 0, w, h);
}

void ViewerWidget::paintGL()
{
	glClearColor(0.3f, 0.3f, 0.3f, 1.f);
	glClear(GL_COLOR_BUFFER_BIT|GL_DEPTH_BUFFER_BIT);
	
	glViewport(0, 0, width(), height());
	
	if( world() == nullptr ) return;

	auto& r = *renderer;

	r.setViewport(width(), height());

	if(dummyObject && dummyObject->animator && dummyObject->skeleton) {
		dummyObject->animator->tick(1.f/60.f);
		dummyObject->skeleton->interpolate(1.f);
	}
	
	gworld->_work->update();

	r.getRenderer()->invalidate();

	glEnable(GL_DEPTH_TEST);

	glm::mat4 m(1.f);

	r.getRenderer()->useProgram(r.worldProg);

	ViewCamera vc;

	float viewFov = glm::radians(45.f);

	vc.frustum.far = 500.f;
	vc.frustum.near = 0.1f;
	vc.frustum.fov = viewFov;
	vc.frustum.aspectRatio = width()/(height()*1.f);

	Model* model = activeModel;
	if( model != _lastModel ) {
		_lastModel = model;
		emit modelChanged(_lastModel);
	}

	glm::vec3 eye(sin(viewAngles.x) * cos(viewAngles.y), cos(viewAngles.x) * cos(viewAngles.y), sin(viewAngles.y));

	if( model )
	{
		glm::mat4 proj = vc.frustum.projection();
		glm::mat4 view = glm::lookAt(eye * viewDistance, glm::vec3(0.f, 0.f, 0.f), glm::vec3(0.f, 0.f, 1.f));

		r.getRenderer()->setSceneParameters({ proj, view, glm::vec4(0.15f), glm::vec4(0.7f), glm::vec4(1.f), glm::vec4(0.f), 90.f, vc.frustum.far });

		r.getRenderer()->invalidate();

		r.setupRender();

		r.renderModel(model, m, dummyObject);

		drawFrameWidget(model->frames[model->rootFrameIdx]);
		r.renderPostProcess();
	}
	else if (world()->allObjects.size() > 0)
	{
		vc.frustum.fov = glm::radians(90.f);
		vc.frustum.far = 1000.f;
		vc.position = viewPosition;
		vc.rotation = glm::angleAxis(glm::half_pi<float>() + viewAngles.x, glm::vec3(0.f, 0.f, 1.f))
					* glm::angleAxis(viewAngles.y, glm::vec3(0.f, 1.f, 0.f));
		r.renderWorld(world(), vc, 0.f);
	}
}

void ViewerWidget::drawFrameWidget(ModelFrame* f, const glm::mat4& m)
{
	auto thisM = m * f->getTransform();
	if(f->getGeometries().size() == 0)
	{
		Renderer::DrawParameters dp;
		dp.count = _frameWidgetGeom->getCount();
		dp.start = 0;
		dp.ambient = 1.f;
		dp.diffuse = 1.f;
		if( f == selectedFrame )
		{
			dp.colour = {255, 255, 0, 255};
			// Sorry!
			glLineWidth(10.f);
		}
		else
		{
			dp.colour = {255, 255, 255, 255};
			glLineWidth(1.f);
		}
		dp.textures = { whiteTex };
		renderer->getRenderer()->drawArrays(thisM, _frameWidgetDraw, dp);
	}
	
	for(auto c : f->getChildren()) {
		drawFrameWidget(c, thisM);
	}
}

GameWorld* ViewerWidget::world()
{
	return gworld;
}

void ViewerWidget::showObject(qint16 item)
{
	currentObjectID = item;

	if( dummyObject ) gworld->destroyObject( dummyObject );

	auto def = world()->data->objectTypes[item];

	if( def )
	{
		if(def->class_type == ObjectData::class_id)
		{
			dummyObject = gworld->createInstance(item, {});
		}
		else if(def->class_type == CharacterData::class_id)
		{
			dummyObject = gworld->createPedestrian(item, {});
		}
		else if(def->class_type == VehicleData::class_id)
		{
			dummyObject = gworld->createVehicle(item, {});
		}
		RW_CHECK(dummyObject != nullptr, "Dummy Object is null");
		if (dummyObject != nullptr) {
			activeModel = dummyObject->model->resource;
		}
	}
}

void ViewerWidget::showModel(Model* model)
{
	if( dummyObject ) gworld->destroyObject( dummyObject );
	dummyObject = nullptr;
	activeModel = model;
}

void ViewerWidget::selectFrame(ModelFrame* frame)
{
	selectedFrame = frame;
}

void ViewerWidget::exportModel()
{
	QString toSv = QFileDialog::getSaveFileName(this,
												"Export Model",
												QDir::homePath(),
												"Model (*.DFF)");

	if( toSv.size() == 0 ) return;

#if 0
	auto it = world()->objectTypes.find(currentObjectID);
	if( it != world()->objectTypes.end() ) {
		for( auto& archive : world()->data.archives ) {
			for(size_t i = 0; i < archive.second.getAssetCount(); ++i) {
				auto& assetI = archive.second.getAssetInfoByIndex(i);
				std::string q(assetI.name);
				std::transform(q.begin(), q.end(), q.begin(), ::tolower);
				if( q.find(it->second->modelName) != q.npos ) {
					archive.second.saveAsset(q, toSv.toStdString());
				}
			}
		}
	}
#endif
}

void ViewerWidget::dataLoaded(GameWorld *world)
{
	gworld = world;
}

void ViewerWidget::setRenderer(GameRenderer *render)
{
	renderer = render;
}

void ViewerWidget::keyPressEvent(QKeyEvent* e)
{
	if (e->key() == Qt::Key_Shift)
		moveFast = true;

	glm::vec3 movement;
	if (e->key() == Qt::Key_W)
		movement.y += moveFast ? 10.f : 1.f;
	if (e->key() == Qt::Key_S)
		movement.y -= moveFast ? 10.f : 1.f;
	if (e->key() == Qt::Key_A)
		movement.x -= moveFast ? 10.f : 1.f;
	if (e->key() == Qt::Key_D)
		movement.x += moveFast? 10.f : 1.f;

	if (movement.length() > 0.f)
	{
		movement = (glm::angleAxis(viewAngles.x, glm::vec3(0.f, 0.f, 1.f))
					* glm::angleAxis(viewAngles.y, glm::vec3(-1.f, 0.f, 0.f))) * movement;
		viewPosition += movement;
	}
}

void ViewerWidget::keyReleaseEvent(QKeyEvent* e)
{
	if (e->key() == Qt::Key_Shift)
		moveFast = false;
}

Model* ViewerWidget::currentModel() const
{
	return activeModel;
}

GameObject* ViewerWidget::currentObject() const
{
	return dummyObject;
}

void ViewerWidget::mousePressEvent(QMouseEvent* e)
{
	dragging = true;
	dstart = e->localPos();
	dastart = viewAngles;
}

void ViewerWidget::mouseReleaseEvent(QMouseEvent*)
{
	dragging = false;
}

void ViewerWidget::mouseMoveEvent(QMouseEvent* e)
{
    if(dragging) {
		auto d = e->localPos() - dstart;
		viewAngles = dastart + glm::vec2(d.x(), d.y()) * 0.01f;
	}
}

void ViewerWidget::wheelEvent(QWheelEvent* e)
{
	viewDistance = qMax(viewDistance - e->angleDelta().y() / 240.f, 0.5f);
}