#include "screen.hpp"

#include <nanogui/opengl.h>
#include <nanogui/glutil.h>
#include <nanogui/screen.h>
#include <nanogui/window.h>
#include <nanogui/layout.h>
#include <nanogui/imageview.h>
#include <nanogui/combobox.h>
#include <nanogui/label.h>
#include <nanogui/toolbutton.h>
#include <nanogui/popupbutton.h>

#include <opencv2/opencv.hpp>

#include <loguru.hpp>

#include "ctrl_window.hpp"
#include "src_window.hpp"
#include "config_window.hpp"
#include "camera.hpp"
#include "media_panel.hpp"

#ifdef HAVE_OPENVR
#include "vr.hpp"
#endif

using ftl::gui::Screen;
using ftl::gui::Camera;
using std::string;
using ftl::rgbd::Source;
using ftl::rgbd::isValidDepth;

namespace {
	constexpr char const *const defaultImageViewVertexShader =
		R"(#version 330
		uniform vec2 scaleFactor;
		uniform vec2 position;
		in vec2 vertex;
		out vec2 uv;
		void main() {
			uv = vertex;
			vec2 scaledVertex = (vertex * scaleFactor) + position;
			gl_Position  = vec4(2.0*scaledVertex.x - 1.0,
								2.0*scaledVertex.y - 1.0,
								0.0, 1.0);
		})";

	constexpr char const *const defaultImageViewFragmentShader =
		R"(#version 330
		uniform sampler2D image1;
		uniform sampler2D image2;
		uniform float blendAmount;
		out vec4 color;
		in vec2 uv;
		void main() {
			color = blendAmount * texture(image1, uv) + (1.0 - blendAmount) * texture(image2, uv);
		})";
}

ftl::gui::Screen::Screen(ftl::Configurable *proot, ftl::net::Universe *pnet, ftl::ctrl::Master *controller) :
		nanogui::Screen(Eigen::Vector2i(1024, 768), "FT-Lab Remote Presence"),
		status_("FT-Lab Remote Presence System") {
	using namespace nanogui;
	net_ = pnet;
	ctrl_ = controller;
	root_ = proot;
	camera_ = nullptr;

	#ifdef HAVE_OPENVR
	HMD_ = nullptr;
	has_vr_ = vr::VR_IsHmdPresent();
	#endif

	setSize(Vector2i(1280,720));

	toolbuttheme = new Theme(*theme());
	toolbuttheme->mBorderDark = nanogui::Color(0,0);
	toolbuttheme->mBorderLight = nanogui::Color(0,0);
	toolbuttheme->mButtonGradientBotFocused = nanogui::Color(60,255);
	toolbuttheme->mButtonGradientBotUnfocused = nanogui::Color(0,0);
	toolbuttheme->mButtonGradientTopFocused = nanogui::Color(60,255);
	toolbuttheme->mButtonGradientTopUnfocused = nanogui::Color(0,0);
	toolbuttheme->mButtonGradientTopPushed = nanogui::Color(60,180);
	toolbuttheme->mButtonGradientBotPushed = nanogui::Color(60,180);
	toolbuttheme->mTextColor = nanogui::Color(0.9f,0.9f,0.9f,0.9f);

	mediatheme = new Theme(*theme());
	mediatheme->mIconScale = 1.2f;
	mediatheme->mWindowDropShadowSize = 0;
	mediatheme->mWindowFillFocused = nanogui::Color(45, 150);
	mediatheme->mWindowFillUnfocused = nanogui::Color(45, 80);
	mediatheme->mButtonGradientTopUnfocused = nanogui::Color(0,0);
	mediatheme->mButtonGradientBotUnfocused = nanogui::Color(0,0);
	mediatheme->mButtonGradientTopFocused = nanogui::Color(80,230);
	mediatheme->mButtonGradientBotFocused = nanogui::Color(80,230);
	mediatheme->mIconColor = nanogui::Color(255,255);
	mediatheme->mTextColor = nanogui::Color(1.0f,1.0f,1.0f,1.0f);
	mediatheme->mBorderDark = nanogui::Color(0,0);
	mediatheme->mBorderMedium = nanogui::Color(0,0);
	mediatheme->mBorderLight = nanogui::Color(0,0);
	mediatheme->mDropShadow = nanogui::Color(0,0);
	mediatheme->mButtonFontSize = 30;
	mediatheme->mStandardFontSize = 20;

	windowtheme = new Theme(*theme());
	windowtheme->mWindowFillFocused = nanogui::Color(220, 200);
	windowtheme->mWindowFillUnfocused = nanogui::Color(220, 200);
	windowtheme->mWindowHeaderGradientBot = nanogui::Color(60,230);
	windowtheme->mWindowHeaderGradientTop = nanogui::Color(60,230);
	windowtheme->mTextColor = nanogui::Color(20,255);
	windowtheme->mWindowCornerRadius = 2;
	windowtheme->mButtonGradientBotFocused = nanogui::Color(210,255);
	windowtheme->mButtonGradientBotUnfocused = nanogui::Color(190,255);
	windowtheme->mButtonGradientTopFocused = nanogui::Color(230,255);
	windowtheme->mButtonGradientTopUnfocused = nanogui::Color(230,255);
	windowtheme->mButtonGradientTopPushed = nanogui::Color(170,255);
	windowtheme->mButtonGradientBotPushed = nanogui::Color(210,255);
	windowtheme->mBorderDark = nanogui::Color(150,255);
	windowtheme->mBorderMedium = nanogui::Color(165,255);
	windowtheme->mBorderLight = nanogui::Color(230,255);
	windowtheme->mButtonFontSize = 16;
	windowtheme->mTextColorShadow = nanogui::Color(0,0);
	windowtheme->mWindowTitleUnfocused = windowtheme->mWindowTitleFocused;
	windowtheme->mWindowTitleFocused = nanogui::Color(240,255);
	windowtheme->mIconScale = 0.85f;

	auto toolbar = new Window(this, "");
	toolbar->setPosition(Vector2i(0,0));
	toolbar->setFixedWidth(50);
	toolbar->setFixedHeight(height());
	//toolbar->setLayout(new BoxLayout(Orientation::Vertical,
	//                               Alignment::Middle, 0, 10));

	setResizeCallback([this,toolbar](Vector2i s) {
		toolbar->setFixedHeight(s[1]);
		mwindow_->setPosition(Vector2i(s[0] / 2 - mwindow_->width()/2, s[1] - 30 - mwindow_->height()));
	});

	auto innertool = new Widget(toolbar);
	innertool->setLayout(new BoxLayout(Orientation::Vertical,
									Alignment::Middle, 0, 10));
	innertool->setPosition(Vector2i(5,10));

	// Padding widget
	//auto w = new Widget(innertool);
	//w->setHeight(10);

	auto button = new ToolButton(innertool, ENTYPO_ICON_HOME);
	button->setIconExtraScale(1.5f);
	button->setTheme(toolbuttheme);
	button->setTooltip("Home");
	button->setFixedSize(Vector2i(40,40));
	button->setCallback([this]() {
		//swindow_->setVisible(true);
		setActiveCamera(nullptr);
	});

	/*button = new ToolButton(innertool, ENTYPO_ICON_PLUS);
	button->setIconExtraScale(1.5f);
	button->setTheme(toolbuttheme);
	button->setTooltip("Add new");
	button->setFixedSize(Vector2i(40,40));
	button->setCallback([this]() {
		//swindow_->setVisible(true);
	});*/

	auto popbutton = new PopupButton(innertool, "", ENTYPO_ICON_PLUS);
	popbutton->setIconExtraScale(1.5f);
	popbutton->setTheme(toolbuttheme);
	popbutton->setTooltip("Add");
	popbutton->setFixedSize(Vector2i(40,40));
	popbutton->setSide(Popup::Side::Right);
	popbutton->setChevronIcon(0);
	Popup *popup = popbutton->popup();
	popup->setLayout(new GroupLayout());
	popup->setTheme(toolbuttheme);
	//popup->setAnchorHeight(100);

	auto itembutton = new Button(popup, "Add Camera", ENTYPO_ICON_CAMERA);
	itembutton->setCallback([this,popup]() {
		swindow_->setVisible(true);
		popup->setVisible(false);
	});

	itembutton = new Button(popup, "Add Node", ENTYPO_ICON_LAPTOP);
	itembutton->setCallback([this,popup]() {
		cwindow_->setVisible(true);
		popup->setVisible(false);
	});

	popbutton = new PopupButton(innertool, "", ENTYPO_ICON_TOOLS);
	popbutton->setIconExtraScale(1.5f);
	popbutton->setTheme(toolbuttheme);
	popbutton->setTooltip("Tools");
	popbutton->setFixedSize(Vector2i(40,40));
	popbutton->setSide(Popup::Side::Right);
	popbutton->setChevronIcon(0);
	popup = popbutton->popup();
	popup->setLayout(new GroupLayout());
	popup->setTheme(toolbuttheme);
	//popbutton->setCallback([this]() {
	//	cwindow_->setVisible(true);
	//});

	itembutton = new Button(popup, "Connections");
	itembutton->setCallback([this,popup]() {
		cwindow_->setVisible(true);
		popup->setVisible(false);
	});

	itembutton = new Button(popup, "Manual Registration");
	itembutton->setCallback([this,popup]() {
		// Show pose win...
		popup->setVisible(false);
	});

	popbutton = new PopupButton(innertool, "", ENTYPO_ICON_COG);
	popbutton->setIconExtraScale(1.5f);
	popbutton->setTheme(toolbuttheme);
	popbutton->setTooltip("Settings");
	popbutton->setFixedSize(Vector2i(40,40));
	popbutton->setSide(Popup::Side::Right);
	popbutton->setChevronIcon(0);
	// popbutton->setPosition(Vector2i(5,height()-50));
	popup = popbutton->popup();
	popup->setLayout(new GroupLayout());
	popup->setTheme(toolbuttheme);

	//net_->onConnect([this,popup](ftl::net::Peer *p) {
	{
		LOG(INFO) << "NET CONNECT";
		auto node_details = ctrl_->getSlaves();
		std::vector<std::string> node_titles;

		for (auto &d : node_details) {
			LOG(INFO) << "ADDING TITLE: " << d.dump();
			auto peer = ftl::UUID(d["id"].get<std::string>());
			auto itembutton = new Button(popup, d["title"].get<std::string>());
			itembutton->setCallback([this,popup,peer]() {
				auto config_window = new ConfigWindow(this, ctrl_, peer);
				config_window->setTheme(windowtheme);
			});
		}
	}
	//});

	itembutton = new Button(popup, "Local");
	itembutton->setCallback([this,popup]() {
		auto config_window = new ConfigWindow(this, ctrl_);
		config_window->setTheme(windowtheme);
	});

	//configwindow_ = new ConfigWindow(parent, ctrl_);
	cwindow_ = new ftl::gui::ControlWindow(this, controller);
	swindow_ = new ftl::gui::SourceWindow(this);
	mwindow_ = new ftl::gui::MediaPanel(this);
	mwindow_->setVisible(false);
	mwindow_->setTheme(mediatheme);

	cwindow_->setPosition(Eigen::Vector2i(80, 20));
	//swindow_->setPosition(Eigen::Vector2i(80, 400));
	cwindow_->setVisible(false);
	swindow_->setVisible(true);
	swindow_->center();
	cwindow_->setTheme(windowtheme);
	swindow_->setTheme(mediatheme);

	mShader.init("RGBDShader", defaultImageViewVertexShader,
				defaultImageViewFragmentShader);

	MatrixXu indices(3, 2);
	indices.col(0) << 0, 1, 2;
	indices.col(1) << 2, 3, 1;

	MatrixXf vertices(2, 4);
	vertices.col(0) << 0, 0;
	vertices.col(1) << 1, 0;
	vertices.col(2) << 0, 1;
	vertices.col(3) << 1, 1;

	mShader.bind();
	mShader.uploadIndices(indices);
	mShader.uploadAttrib("vertex", vertices);

	setVisible(true);
	performLayout();
}

#ifdef HAVE_OPENVR
bool ftl::gui::Screen::initVR() {
	if (!vr::VR_IsHmdPresent()) {
		return false;
	}

	vr::EVRInitError eError = vr::VRInitError_None;
	HMD_ = vr::VR_Init( &eError, vr::VRApplication_Scene );
	
	if (eError != vr::VRInitError_None)
	{
		HMD_ = nullptr;
		LOG(ERROR) << "Unable to init VR runtime: " << vr::VR_GetVRInitErrorAsEnglishDescription(eError);
		return false;
	}

	return true;
}

bool ftl::gui::Screen::useVR() {
	auto *cam = activeCamera();
	if (HMD_ == nullptr || cam == nullptr) { return false; }
	return cam->isVR();
}

bool ftl::gui::Screen::switchVR(bool on) {
	if (useVR() == on) { return on; }

	if (on && (HMD_ == nullptr) && !initVR()) {
		return false;
	}

	if (on) {
		activeCamera()->setVR(true);
	} else {
		activeCamera()->setVR(false);
	}
	
	return useVR();
}
#endif

ftl::gui::Screen::~Screen() {
	mShader.free();

	#ifdef HAVE_OPENVR
	if (HMD_ != nullptr) {
		vr::VR_Shutdown();
	}
	#endif
}

void ftl::gui::Screen::setActiveCamera(ftl::gui::Camera *cam) {
	camera_ = cam;

	if (cam) {
		status_ = cam->source()->getURI();
		mwindow_->setVisible(true);
		mwindow_->cameraChanged();
		swindow_->setVisible(false);
	} else {
		mwindow_->setVisible(false);
		swindow_->setVisible(true);
		status_ = "[No camera]";
	}
}

bool ftl::gui::Screen::mouseMotionEvent(const Eigen::Vector2i &p, const Eigen::Vector2i &rel, int button, int modifiers) {
	if (nanogui::Screen::mouseMotionEvent(p, rel, button, modifiers)) {
		return true;
	} else {
		if (camera_) camera_->mouseMovement(rel[0], rel[1], button);
	}
	return true; // TODO: return statement was missing; is true correct?
}

bool ftl::gui::Screen::mouseButtonEvent(const nanogui::Vector2i &p, int button, bool down, int modifiers) {
	if (nanogui::Screen::mouseButtonEvent(p, button, down, modifiers)) {
		return true;
	} else {
		if (camera_ && down) {
			Eigen::Vector2f screenSize = size().cast<float>();
			auto mScale = (screenSize.cwiseQuotient(imageSize).minCoeff());
			Eigen::Vector2f scaleFactor = mScale * imageSize.cwiseQuotient(screenSize);
			Eigen::Vector2f positionInScreen(0.0f, 0.0f);
			auto mOffset = (screenSize - (screenSize.cwiseProduct(scaleFactor))) / 2;
			Eigen::Vector2f positionAfterOffset = positionInScreen + mOffset;

			float sx = ((float)p[0] - positionAfterOffset[0]) / mScale;
			float sy = ((float)p[1] - positionAfterOffset[1]) / mScale;

			//Eigen::Vector4f camPos;

			//try {
				//camPos = camera_->source()->point(sx,sy).cast<float>();
			//} catch(...) {
			//	return true;
			//}
			
			//camPos *= -1.0f;
			//Eigen::Vector4f worldPos =  camera_->source()->getPose().cast<float>() * camPos;
			//lookPoint_ = Eigen::Vector3f(worldPos[0],worldPos[1],worldPos[2]);
			//LOG(INFO) << "Depth at click = " << -camPos[2];
			return true;
		}
	return false;
	}
}

bool ftl::gui::Screen::keyboardEvent(int key, int scancode, int action, int modifiers) {
	using namespace Eigen;
	if (nanogui::Screen::keyboardEvent(key, scancode, action, modifiers)) {
		return true;
	} else {
		LOG(INFO) << "Key press " << key << " - " << action << " - " << modifiers;

		if (key >= 262 && key <= 267) {
			if (camera_) camera_->keyMovement(key, modifiers);
			return true;
		} else if (action == 1 && key == 'H') {
			swindow_->setVisible(false);
			cwindow_->setVisible(false);
		} else if (action == 1 && key == 32) {
			ctrl_->pause();
			return true;
		}
		return false;
	}
}

void ftl::gui::Screen::draw(NVGcontext *ctx) {
	using namespace Eigen;

	Vector2f screenSize = size().cast<float>();

	if (camera_) {
		imageSize = {camera_->width(), camera_->height()};

		mImageID = camera_->captureFrame().texture();
		leftEye_ = mImageID;
		rightEye_ = camera_->getRight().texture();

		if (camera_->getChannel() != ftl::codecs::Channel::Left) { mImageID = rightEye_; }

		#ifdef HAVE_OPENVR
		if (useVR() && imageSize[0] > 0 && camera_->getLeft().isValid() && camera_->getRight().isValid()) {
			
			vr::Texture_t leftEyeTexture = {(void*)(uintptr_t)leftEye_, vr::TextureType_OpenGL, vr::ColorSpace_Gamma };
			vr::VRCompositor()->Submit(vr::Eye_Left, &leftEyeTexture );

			glBindTexture(GL_TEXTURE_2D, rightEye_);
			vr::Texture_t rightEyeTexture = {(void*)(uintptr_t)rightEye_, vr::TextureType_OpenGL, vr::ColorSpace_Gamma };
			vr::VRCompositor()->Submit(vr::Eye_Right, &rightEyeTexture );
			
			mImageID = leftEye_;
		}
		#endif

		if (mImageID < std::numeric_limits<unsigned int>::max() && imageSize[0] > 0) {
			auto mScale = (screenSize.cwiseQuotient(imageSize).minCoeff());
			Vector2f scaleFactor = mScale * imageSize.cwiseQuotient(screenSize);
			Vector2f positionInScreen(0.0f, 0.0f);
			auto mOffset = (screenSize - (screenSize.cwiseProduct(scaleFactor))) / 2;
			Vector2f positionAfterOffset = positionInScreen + mOffset;
			Vector2f imagePosition = positionAfterOffset.cwiseQuotient(screenSize);
			//glEnable(GL_SCISSOR_TEST);
			//float r = screen->pixelRatio();
			/* glScissor(positionInScreen.x() * r,
					(screenSize.y() - positionInScreen.y() - size().y()) * r,
					size().x() * r, size().y() * r);*/
			mShader.bind();
			glActiveTexture(GL_TEXTURE0);
			glBindTexture(GL_TEXTURE_2D, leftEye_);
			glActiveTexture(GL_TEXTURE1);
			glBindTexture(GL_TEXTURE_2D, (camera_->getRight().isValid()) ? rightEye_ : leftEye_);
			mShader.setUniform("image1", 0);
			mShader.setUniform("image2", 1);
			mShader.setUniform("blendAmount", (camera_->getChannel() != ftl::codecs::Channel::Left) ? root_->value("blending", 0.5f) : 1.0f);
			mShader.setUniform("scaleFactor", scaleFactor);
			mShader.setUniform("position", imagePosition);
			mShader.drawIndexed(GL_TRIANGLES, 0, 2);
			//glDisable(GL_SCISSOR_TEST);
		}
	}

	nvgTextAlign(ctx, NVG_ALIGN_RIGHT);
	nvgText(ctx, screenSize[0]-10, screenSize[1]-20, status_.c_str(), NULL);

	/* Draw the user interface */
	screen()->performLayout(ctx);
	nanogui::Screen::draw(ctx);
}