/*
	QGLView
	Copyright (C) 2019  Ivan Pelipenko peri4ko@yandex.ru

	This program is free software: you can redistribute it and/or modify
	it under the terms of the GNU General Public License as published by
	the Free Software Foundation, either version 3 of the License, or
	(at your option) any later version.

	This program is distributed in the hope that it will be useful,
	but WITHOUT ANY WARRANTY; without even the implied warranty of
	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
	GNU General Public License for more details.

	You should have received a copy of the GNU General Public License
	along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

#include "qglview.h"
#include "glmesh.h"
#include "gltexture_manager.h"
#include <chunkstream.h>
#include <QApplication>
#include <QOpenGLTexture>
#include <QKeyEvent>

using namespace QGLEngineShaders;


QGLView::QGLView(): OpenGLWindow(), renderer_(this) {
	setIcon(QIcon(":/icons/qglview.png"));
	deleting_ = false;
	timer = 0;
	need_init_ = is_first_draw = true;
	backColor_ = Qt::darkGray;
	hoverHaloColor_ = QColor(195, 140, 255);
	selectionHaloColor_ = QColor(175, 255, 140);
	ambientColor_ = QColor(10, 10, 10);
	lastPos = QPoint(-1, -1);
	lineWidth_ = 1.;
	max_anisotropic = 1;
	max_texture_chanels = 8;
	cameraOrbit_ = lightEnabled_ = canSelect_ = true;
	shaders_supported = selecting_ = customMouseMove_ = false;
	sel_button = Qt::LeftButton;
	sel_mod = Qt::ControlModifier;
	fps_cnt = 0;
	fps_tm = fps_ = 0.;
	fogDensity_ = fogEnd_ = 1.;
	fogStart_ = 0.;
	hoverHaloFill_ = selectionHaloFill_ = 0.15f;
	//lmode = Simple;
	setFeature(qglFXAA, false);
	setFeature(qglAnisotropicLevel, 8);
	setFeature(qglEyeAccomodationEnabled, false);
	setFeature(qglEyeAccomodationTime, 16.);
	setFeature(qglEyeAccomodationMaxSpeed, 0.2);
	setFeature(qglBloomEnabled, false);
	setFeature(qglBloomThreshold, 0.9);
	setFeature(qglBloomFactor, 1.);
	setFeature(qglBloomRadius, 8);
	setFeature(qglMotionBlurEnabled, false);
	setFeature(qglMotionBlurFactor, 1.);
	setFeature(qglMotionBlurSteps, 8);
	setFeature(qglShadowsEnabled, false);
	setFeature(qglShadowsMapSize, 512);
	setFeature(qglShadowsSoftEnabled, true);
	setFeature(qglReflectionsEnabled, false);
	setFeature(qglReflectionsBlur, true);
	setFeature(qglSSAOEnabled, false);
	setFeature(qglSSAORadius, 5);
	setFeature(qglDepthOfFieldEnabled, false);
	setFeature(qglDepthOfFieldAutoFocusEnabled, true);
	setFeature(qglDepthOfFieldAutoFocusSpeed, 0.1);
	setFeature(qglDepthOfFieldFocus, 1.);
	setFeature(qglDepthOfFieldDiaphragm, 8.);
	mouse_first = mouseSelect_ = hoverHalo_ = selectionHalo_ = true;
	mouseRotate_ = true;
	fogEnabled_ = is_init = grabMouse_ = shaders_bind = changed_ = false;
	rmode = ObjectBase::Fill;
//	sel_pen = QPen(Qt::black, 1, Qt::DashLine);
//	sel_brush = QBrush(QColor(170, 100, 255, 120));
	scene_ = new Scene();
	connect(scene_, SIGNAL(selectionChanged()), this, SIGNAL(selectionChanged()));
	connect(scene_, SIGNAL(__destroyed()), this, SLOT(__destroyed()));
	camera_ = new Camera();
	camera_->setAim(QVector3D());
	camera_->setPos(QVector3D(2, 2, 2));
	camera_->setName("Camera");
	emit cameraPosChanged(camera_->pos());
	//camera().aim_ = camera().pos_;
	ktm_.restart();

	Mesh * m = Primitive::cube();
	ObjectBase * o = new ObjectBase(m);
	o->setColor(Qt::cyan);
	scene()->addObject(o);
	delete m;

}


QGLView::~QGLView() {
	deleting_ = true;
	stop();
	scene_->destroy();
	delete scene_;
}


void QGLView::stop() {
	if (timer) killTimer(timer);
}


void QGLView::start(float freq) {
	timer = startTimer(freq <= 0.f ? 0 : int(1000.f / freq));
}


Scene::SelectionMode QGLView::selectionMode() const {
	return scene_->selectionMode();
}


void QGLView::setSelectionMode(Scene::SelectionMode m) {
	scene_->setSelectionMode(m);
}


void QGLView::selectObject(ObjectBase * o, bool add_to_selection) {
	scene_->selectObject(o, add_to_selection);
}


void QGLView::clearSelection() {
	scene_->clearSelection();
}


QList<ObjectBase * > QGLView::selectedObjects() const {
	return scene_->selectedObjects();
}


ObjectBase * QGLView::selectedObject() const {
	return scene_->selectedObject();
}



void QGLView::resizeEvent(QResizeEvent * e) {
	renderLater();
}


void QGLView::timerEvent(QTimerEvent *) {
	renderNow();
	//if (ktm_.elapsed() < QApplication::keyboardInputInterval()) return;
	Qt::KeyboardModifiers km = QApplication::keyboardModifiers();
	foreach (int i, keys_)
		emit keyEvent((Qt::Key)i, km);
}


void QGLView::render() {
	resizeGL(width(), height());
	emit glBeginPaint();
	renderer_.mouse_pos = mapFromGlobal(QCursor::pos());
	renderer_.renderScene();
	emit glPainting();
	emit glEndPaint();
	fps_tm += time.elapsed();
	time.restart();
	fps_cnt++;
	if (fps_tm < 1000.) return;
	fps_ = fps_cnt / fps_tm * 1000.;
	fps_tm = 0.;
	fps_cnt = 0;
}


void QGLView::initialize() {
	checkCaps();
	renderer_.reloadShaders();
	renderer_.init(width(), height());
	glPixelStorei(GL_PACK_ALIGNMENT, 1);
	glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
	glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
	glDisable(GL_MULTISAMPLE);
	glDisable(GL_BLEND);
	glEnable(GL_TEXTURE_2D);
	glEnable(GL_TEXTURE_MAX_ANISOTROPY_EXT);
	glEnable(GL_CULL_FACE);
	glCullFace(GL_BACK);
	is_init = true;
	need_init_ = false;
	emit glInitializeDone();
}


void QGLView::checkCaps() {
	glGetIntegerv(GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT, &max_anisotropic);
	shaders_supported = QOpenGLShaderProgram::hasOpenGLShaderPrograms();
}


void QGLView::__destroyed() {
	renderer_.rend_mat.mat_thumbnails.clear();
	hov_objects.clear();
}


void QGLView::resizeGL(int width, int height) {
	if (!is_init) return;
	if (width <= 0 || height <= 0) return;
	if (prev_size == QSize(width, height)) return;
	prev_size = QSize(width, height);
	aspect = float(width) / float(height);
	renderer_.resize(width, height);
	mouse_first = true;
	//qDebug() << "resize" << width << height;
	iaspect = (aspect == 0.f) ? 0. : 1 / aspect;
	glViewport(0, 0, width, height);
	emit glResize(width, height);
}


void QGLView::mouseReleaseEvent(QMouseEvent * e) {
	bool add_ts = e->modifiers().testFlag(sel_mod);
	if (selecting_) {
		selecting_ = false;
		canSelect_ = true;
		renderer_.mouse_rect = QRect();
		scene_->selectObjects(hov_objects.toList(), add_ts);
		return;
	}
	if (canSelect_ && mouseSelect_ && e->button() == Qt::LeftButton) {
		if ((lastPos - downPos).manhattanLength() < QApplication::startDragDistance() && !hov_objects.isEmpty()) {
			scene_->selectObject(hov_objects[0], add_ts);
		}
	}
	canSelect_ = e->buttons() == 0;
	emit glMouseReleaseEvent(e);
}


void QGLView::mousePressEvent(QMouseEvent * e) {
	if (selecting_) {
		downPos = e->pos();
		selecting_ = false;
		renderer_.mouse_rect = QRect();
		return;
	}
	if (!QRect(QPoint(), size()).contains(e->pos())) return;
	lastPos = e->pos();
	downPos = lastPos;
	emit glMousePressEvent(e);
}


void QGLView::mouseMoveEvent(QMouseEvent * e) {
	QPoint cpos = e->pos();
	if (selecting_) {
		renderer_.mouse_rect = QRect(downPos, cpos).normalized();
		return;
	}
	if (e->buttons().testFlag(Qt::LeftButton)) {
		if ((cpos - downPos).manhattanLength() >= QApplication::startDragDistance()) {
			selecting_ = true;
			canSelect_ = false;
		}
		return;
	}
	QRect g_rect(QPoint(), size());
	if (mouseRotate_) {
		float dx = e->x() - lastPos.x();
		float dy = e->y() - lastPos.y();
		if (e->buttons().testFlag(Qt::MidButton)) {
			if (cameraOrbit_) {
				camera()->orbitZ(dx / 4.f);
				camera()->orbitXY(dy / 4.f);
			} else {
				camera()->rotateZ(dx / 4.f);
				camera()->rotateXY(dy / 4.f);
			}
			emit cameraPosChanged(camera()->pos());
		} else if (e->buttons().testFlag(Qt::RightButton)) {
			float ad = camera()->distance();
			camera()->moveLeft(dx / 1000.f * ad);
			camera()->moveUp(dy / 1000.f * ad);
			emit cameraPosChanged(camera()->pos());
		}
	}
	lastPos = e->pos();
	if (customMouseMove_) emit customMouseMoveEvent(e->pos(), lastPos, e->buttons());
	if (grabMouse_) {
		QCursor::setPos(mapToGlobal(QRect(QPoint(), size()).center()));
		static bool mouse_sec = false;
		if (mouse_sec) {
			mouse_sec = false;
			return;
		}
		if (mouse_first) {
			mouse_first = false;
			mouse_sec = true;
			return;
		}
		lastPos = g_rect.center();
		int dx = e->x() - lastPos.x();
		int dy = e->y() - lastPos.y();
		emit glMouseMoveEvent(new QMouseEvent(QEvent::MouseMove, QPoint(dx, dy), e->button(), e->buttons(), e->modifiers()));
		return;
	}
	emit glMouseMoveEvent(e);
}


void QGLView::wheelEvent(QWheelEvent * e) {
	if (mouseRotate_) {
		if (e->delta() > 0) camera()->flyCloser(0.1f);
		if (e->delta() < 0) camera()->flyFarer(0.1f);
		emit cameraPosChanged(camera()->pos());
	}
	emit glWheelEvent(e);
}


void QGLView::leaveEvent(QEvent * ) {
	lastPos = QPoint(-1, -1);
	//qDebug() << lastPos;
}


void QGLView::keyPressEvent(QKeyEvent * e) {
	emit glKeyPressEvent(e);
	if (e->key() > 0) keys_.insert(e->key());
	if (e->key() == Qt::Key_F11) {
		emit doubleClick();
	}
}


void QGLView::keyReleaseEvent(QKeyEvent * e) {
	emit glKeyReleaseEvent(e);
	keys_.remove(e->key());
}


void QGLView::focusOutEvent(QFocusEvent *) {
	keys_.clear();
}


void QGLView::mouseDoubleClickEvent(QMouseEvent * e) {
	if (e->buttons().testFlag(Qt::MidButton))
		emit doubleClick();
}


Camera * QGLView::camera() {
	return camera_;
}


const Camera * QGLView::camera() const {
	return camera_;
}


void QGLView::setCamera(Camera * camera) {
	camera_ = camera;
}


TextureManager * QGLView::textureManager() {
	return renderer_.textures_manager;
}


void QGLView::reloadTextures() {
	renderer_.markReloadTextures();
}


void QGLView::focusOn(const Box3D & bb) {
	if (bb.isEmpty() || !camera()) return;
	double size = qMax(qMax(bb.width, bb.length), bb.height);
	camera()->setAim(bb.center());
	camera()->flyToDistance(size * 1.25);
}


void QGLView::setCameraLightOn(bool on) {
	renderer_.setCameraLightOn(on);
}


bool QGLView::isCameraLightOn() const {
	return renderer_.isCameraLightOn();
}


QByteArray QGLView::saveCamera() {
	ChunkStream cs;
	const Camera * c = camera();
	cs.add(1, c->pos()).add(2, c->aim()).add(3, c->angles()).add(4, c->FOV());
	return cs.data();
}


void QGLView::restoreCamera(const QByteArray & ba) {
	if (ba.isEmpty()) return;
	Camera * c = camera();
	QVector3D pos(c->pos()), aim(c->aim()), ang(c->angles());
	float fov(c->FOV());
	ChunkStream cs(ba);
	cs.readAll();
	cs.get(1, pos).get(2, aim).get(3, ang).get(4, fov);
	camera()->setPos(pos);
	camera()->setAim(aim);
	camera()->setAngles(ang);
	camera()->setFOV(fov);
}


QByteArray QGLView::saveFeatures() {
	QByteArray ba;
	QDataStream ds(&ba, QIODevice::WriteOnly);
	ds << features_;
	return ba;
}


void QGLView::restoreFeatures(const QByteArray & ba) {
	QHash<int, QVariant> f;
	QDataStream ds(ba);
	ds >> f;
	features_ = f;
}


QImage QGLView::materialThumbnail(Material * m) {
	return renderer_.materialThumbnail(m);
}