/* -*- Mode: C++; indent-tabs-mode: t; c-basic-offset: 4; tab-width: 4 -*-  */
/*
 * DisplayerToolSelect.cc
 * Copyright (C) 2013-2018 Sandro Mani <manisandro@gmail.com>
 *
 * gImageReader 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.
 *
 * gImageReader 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 "DisplayerToolSelect.hh"
#include "Displayer.hh"
#include "FileDialogs.hh"
#include "MainWindow.hh"
#include "Recognizer.hh"
#include "Utils.hh"
#include "ui_SelectionMenu.hh"

#include <cmath>
#define USE_STD_NAMESPACE
#include <tesseract/baseapi.h>
#undef USE_STD_NAMESPACE


DisplayerToolSelect::DisplayerToolSelect(Displayer* displayer)
	: DisplayerTool(displayer) {
	displayer->setDefaultCursor(Gdk::Cursor::create(Gdk::TCROSS));
	updateRecognitionModeLabel();
}

DisplayerToolSelect::~DisplayerToolSelect() {
	clearSelections();
}

bool DisplayerToolSelect::mousePressEvent(GdkEventButton* event) {
	if(event->button == 1 &&  m_curSel == nullptr) {
		if((event->state & Gdk::CONTROL_MASK) == 0) {
			clearSelections();
		}
		m_curSel = new NumberedDisplayerSelection(this, 1 + m_selections.size(), m_displayer->mapToSceneClamped(Geometry::Point(event->x, event->y)));
		m_curSel->setZIndex(1 + m_selections.size());
		m_displayer->addItem(m_curSel);
		return true;
	}
	return false;
}

bool DisplayerToolSelect::mouseMoveEvent(GdkEventMotion* event) {
	if(m_curSel) {
		Geometry::Point p = m_displayer->mapToSceneClamped(Geometry::Point(event->x, event->y));
		m_curSel->setPoint(p);
		m_displayer->ensureVisible(event->x, event->y);
		return true;
	}
	return false;
}

bool DisplayerToolSelect::mouseReleaseEvent(GdkEventButton* /*event*/) {
	if(m_curSel) {
		if(m_curSel->rect().width < 5. || m_curSel->rect().height < 5.) {
			m_displayer->removeItem(m_curSel);
			delete m_curSel;
		} else {
			m_selections.push_back(m_curSel);
			updateRecognitionModeLabel();
		}
		m_curSel = nullptr;
		return true;
	}
	return false;
}

void DisplayerToolSelect::resolutionChanged(double factor) {
	for(NumberedDisplayerSelection* sel : m_selections) {
		sel->scale(factor);
	}
}

void DisplayerToolSelect::rotationChanged(double delta) {
	Geometry::Rotation R(delta);
	for(NumberedDisplayerSelection* sel : m_selections) {
		sel->rotate(R);
	}
}

std::vector<Cairo::RefPtr<Cairo::ImageSurface>> DisplayerToolSelect::getOCRAreas() {
	std::vector<Cairo::RefPtr<Cairo::ImageSurface>> images;
	if(m_selections.empty()) {
		images.push_back(m_displayer->getImage(m_displayer->getSceneBoundingRect()));
	} else {
		for(const NumberedDisplayerSelection* sel : m_selections) {
			images.push_back(m_displayer->getImage(sel->rect()));
		}
	}
	return images;
}

void DisplayerToolSelect::clearSelections() {
	for(NumberedDisplayerSelection* sel : m_selections) {
		m_displayer->removeItem(sel);
		delete sel;
	}
	m_selections.clear();
	updateRecognitionModeLabel();
}

void DisplayerToolSelect::removeSelection(int num) {
	m_displayer->removeItem(m_selections[num - 1]);
	delete m_selections[num - 1];
	m_selections.erase(m_selections.begin() + num - 1);
	for(int i = 0, n = m_selections.size(); i < n; ++i) {
		m_selections[i]->setNumber(1 + i);
		m_selections[i]->setZIndex(1 + i);
	}
}

void DisplayerToolSelect::reorderSelection(int oldNum, int newNum) {
	NumberedDisplayerSelection* sel = m_selections[oldNum - 1];
	m_selections.erase(m_selections.begin() + oldNum - 1);
	m_selections.insert(m_selections.begin() + newNum - 1, sel);
	for(int i = 0, n = m_selections.size(); i < n; ++i) {
		m_selections[i]->setNumber(1 + i);
		m_selections[i]->setZIndex(1 + i);
	}
}

void DisplayerToolSelect::saveSelection(NumberedDisplayerSelection* selection) {
	Cairo::RefPtr<Cairo::ImageSurface> img = m_displayer->getImage(selection->rect());
	FileDialogs::FileFilter filter = {_("PNG Images"), {"image/png"}, {"*.png"}};
	std::string filename = FileDialogs::save_dialog(_("Save Selection Image"), _("selection.png"), "outputdir", filter, true);
	if(!filename.empty()) {
		img->write_to_png(filename);
	}
}

void DisplayerToolSelect::updateRecognitionModeLabel() {
	MAIN->getRecognizer()->setRecognizeMode(m_selections.empty() ? _("Recognize all") : _("Recognize selection"));
}

void DisplayerToolSelect::autodetectLayout(bool noDeskew) {
	clearSelections();

	double avgDeskew = 0.;
	int nDeskew = 0;
	std::vector<Geometry::Rectangle> rects;
	Cairo::RefPtr<Cairo::ImageSurface> img = m_displayer->getImage(m_displayer->getSceneBoundingRect());

	// Perform layout analysis
	Utils::busyTask([this, &nDeskew, &avgDeskew, &rects, &img] {
		std::string current = setlocale(LC_ALL, NULL);
		setlocale(LC_ALL, "C");
		tesseract::TessBaseAPI tess;
		tess.InitForAnalysePage();
		setlocale(LC_ALL, current.c_str());
		tess.SetPageSegMode(tesseract::PSM_AUTO_ONLY);
		tess.SetImage(img->get_data(), img->get_width(), img->get_height(), 4, 4 * img->get_width());
		tesseract::PageIterator* it = tess.AnalyseLayout();
		if(it && !it->Empty(tesseract::RIL_BLOCK)) {
			do {
				int x1, y1, x2, y2;
				tesseract::Orientation orient;
				tesseract::WritingDirection wdir;
				tesseract::TextlineOrder tlo;
				float deskew;
				it->BoundingBox(tesseract::RIL_BLOCK, &x1, &y1, &x2, &y2);
				it->Orientation(&orient, &wdir, &tlo, &deskew);
				avgDeskew += deskew;
				++nDeskew;
				float width = x2 - x1, height = y2 - y1;
				if(width > 10 && height > 10) {
					rects.push_back(Geometry::Rectangle(x1 - 0.5 * img->get_width(), y1 - 0.5 * img->get_height(), width, height));
				}
			} while(it->Next(tesseract::RIL_BLOCK));
		}
		delete it;
		return true;
	}, _("Performing layout analysis"));

	// If a somewhat large deskew angle is detected, automatically rotate image and redetect layout,
	// unless we already attempted to rotate (to prevent endless loops)
	avgDeskew = Utils::round(((avgDeskew / nDeskew) / M_PI * 180.) * 10.) / 10.;
	if(std::abs(avgDeskew) > .1 && !noDeskew) {
		double newangle = m_displayer->getCurrentAngle() - avgDeskew;
		m_displayer->setup(nullptr, nullptr, &newangle);
		autodetectLayout(true);
	} else {
		// Merge overlapping rectangles
		for(int i = rects.size(); i-- > 1;) {
			for(int j = i; j-- > 0;) {
				if(rects[j].overlaps(rects[i])) {
					rects[j] = rects[j].unite(rects[i]);
					rects.erase(rects.begin() + i);
					break;
				}
			}
		}
		for(int i = 0, n = rects.size(); i < n; ++i) {
			m_selections.push_back(new NumberedDisplayerSelection(this, 1 + i, Geometry::Point(rects[i].x, rects[i].y)));
			m_selections.back()->setPoint(Geometry::Point(rects[i].x + rects[i].width, rects[i].y + rects[i].height));
			m_displayer->addItem(m_selections.back());
		}
		updateRecognitionModeLabel();
	}
}

///////////////////////////////////////////////////////////////////////////////

void NumberedDisplayerSelection::showContextMenu(GdkEventButton* event) {
	Ui::SelectionMenu ui;
	ClassData m_classdata;
	ui.setupUi();
	ui.windowSelection->set_attached_to(*MAIN->getWindow());
	ui.spinSelectionOrder->get_adjustment()->set_upper(static_cast<DisplayerToolSelect*>(m_tool)->m_selections.size());
	ui.spinSelectionOrder->get_adjustment()->set_value(m_number);

	Glib::RefPtr<Glib::MainLoop> loop = Glib::MainLoop::create();
	std::vector<sigc::connection> selmenuConnections = {
		CONNECT(ui.spinSelectionOrder, value_changed, [&]{ reorderSelection(ui.spinSelectionOrder->get_value()); }),
		CONNECT(ui.buttonSelectionDelete, clicked, [&]{
			loop->quit();
			static_cast<DisplayerToolSelect*>(m_tool)->removeSelection(m_number);
		}),
		CONNECT(ui.buttonSelectionRecognize, clicked, [&]{
			loop->quit();
			MAIN->getRecognizer()->recognizeImage(displayer()->getImage(rect()), Recognizer::OutputDestination::Buffer);
		}),
		CONNECT(ui.buttonSelectionClipboard, clicked, [&]{
			loop->quit();
			MAIN->getRecognizer()->recognizeImage(displayer()->getImage(rect()), Recognizer::OutputDestination::Clipboard);
		}),
		CONNECT(ui.buttonSelectionSave, clicked, [&]{
			loop->quit();
			// Explicitly hide (and wait for hide event to be processed) to avoid key/mouse-grab conflicts with file dialog which pops up
			ui.windowSelection->hide();
			while(Gtk::Main::events_pending()) {
				Gtk::Main::iteration(false);
			}
			static_cast<DisplayerToolSelect*>(m_tool)->saveSelection(this);
		}),
		CONNECT(ui.windowSelection, button_press_event, [&](GdkEventButton * ev) {
			Gtk::Allocation a = ui.windowSelection->get_allocation();
			if(ev->x < a.get_x() || ev->x > a.get_x() + a.get_width() || ev->y < a.get_y() || ev->y > a.get_y() + a.get_height()) {
				loop->quit();
			}
			return true;
		}),
		CONNECT(ui.windowSelection, key_press_event, [&](GdkEventKey * ev) {
			if(ev->keyval == GDK_KEY_Escape) { loop->quit(); }
			return true;
		})
	};
	Glib::RefPtr<const Gdk::Screen> screen = MAIN->getWindow()->get_screen();
	Gdk::Rectangle rect = screen->get_monitor_workarea(screen->get_monitor_at_point(event->x_root, event->y_root));
	ui.windowSelection->show_all();
	int w, h, trash;
	ui.windowSelection->get_preferred_width(trash, w);
	ui.windowSelection->get_preferred_height(trash, h);
	int x = std::min(std::max(int(event->x_root), rect.get_x()), rect.get_x() + rect.get_width() - w);
	int y = std::min(std::max(int(event->y_root), rect.get_y()), rect.get_y() + rect.get_height() - h);
	ui.windowSelection->move(x, y);
	GdkWindow* gdkwin = ui.windowSelection->get_window()->gobj();
#if GTK_CHECK_VERSION(3,20,0)
	gdk_seat_grab(gdk_device_get_seat(gtk_get_current_event_device()), gdkwin, GDK_SEAT_CAPABILITY_ALL, true, nullptr, nullptr, nullptr, nullptr);
#else
	gdk_device_grab(gtk_get_current_event_device(), gdkwin, GDK_OWNERSHIP_APPLICATION, true, GDK_BUTTON_PRESS_MASK, nullptr, event->time);
#endif

	loop->run();

	ui.windowSelection->hide();
	for(sigc::connection& conn : selmenuConnections) {
		conn.disconnect();
	}
#if GTK_CHECK_VERSION(3,20,0)
	gdk_seat_ungrab(gdk_device_get_seat(gtk_get_current_event_device()));
#else
	gdk_device_ungrab(gtk_get_current_event_device(), gtk_get_current_event_time());
#endif
}

void NumberedDisplayerSelection::reorderSelection(int newNumber) {
	static_cast<DisplayerToolSelect*>(m_tool)->reorderSelection(m_number, newNumber);
}

void NumberedDisplayerSelection::draw(Cairo::RefPtr<Cairo::Context> ctx) const {
	DisplayerSelection::draw(ctx);

	Gdk::RGBA fgcolor("#FFFFFF");
	Gdk::RGBA bgcolor("#4A90D9");

	double scale = displayer()->getCurrentScale();
	Glib::ustring idx = Glib::ustring::compose("%1", m_number);

	double d = 0.5 / scale;
	double x1 = Utils::round(rect().x * scale) / scale + d;
	double y1 = Utils::round(rect().y * scale) / scale + d;
	double x2 = Utils::round((rect().x + rect().width) * scale) / scale - d;
	double y2 = Utils::round((rect().y + rect().height) * scale) / scale - d;
	Geometry::Rectangle paintrect(x1, y1, x2 - x1, y2 - y1);
	ctx->save();
	// Text box
	double w = std::min(std::min(40. * d, paintrect.width), paintrect.height);
	ctx->rectangle(paintrect.x, paintrect.y, w - d, w - d);
	ctx->set_source_rgba(bgcolor.get_red(), bgcolor.get_green(), bgcolor.get_blue(), 1.0);
	ctx->fill();
	// Text
	ctx->select_font_face("sans", Cairo::FONT_SLANT_NORMAL, Cairo::FONT_WEIGHT_BOLD);
	ctx->set_font_size(0.7 * w);
	Cairo::TextExtents ext;
	ctx->get_text_extents(idx, ext);
	ctx->translate(paintrect.x + .5 * w, paintrect.y + .5 * w);
	ctx->translate(-ext.x_bearing - .5 * ext.width, -ext.y_bearing - .5 * ext.height);
	ctx->set_source_rgba(fgcolor.get_red(), fgcolor.get_green(), bgcolor.get_blue(), 1.0);
	ctx->show_text(idx);
	ctx->restore();
}
