GenericWelcomeView.java

package kornell.gui.client.presentation.welcome.generic;

import java.util.ArrayList;
import java.util.List;

import com.github.gwtbootstrap.client.ui.constants.AlertType;
import com.github.gwtbootstrap.client.ui.constants.IconType;
import com.google.gwt.core.client.GWT;
import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.place.shared.PlaceChangeEvent;
import com.google.gwt.place.shared.PlaceController;
import com.google.gwt.uibinder.client.UiBinder;
import com.google.gwt.uibinder.client.UiField;
import com.google.gwt.user.client.ui.Button;
import com.google.gwt.user.client.ui.Composite;
import com.google.gwt.user.client.ui.FlowPanel;
import com.google.gwt.user.client.ui.IsWidget;
import com.google.gwt.user.client.ui.Widget;
import com.google.web.bindery.event.shared.EventBus;

import kornell.api.client.Callback;
import kornell.api.client.KornellSession;
import kornell.core.entity.EnrollmentProgressDescription;
import kornell.core.to.CourseClassTO;
import kornell.core.to.CourseClassesTO;
import kornell.gui.client.ClientFactory;
import kornell.gui.client.KornellConstants;
import kornell.gui.client.ViewFactory;
import kornell.gui.client.event.CourseClassesFetchedEvent;
import kornell.gui.client.personnel.Student;
import kornell.gui.client.personnel.Teacher;
import kornell.gui.client.personnel.Teachers;
import kornell.gui.client.presentation.welcome.WelcomePlace;
import kornell.gui.client.presentation.welcome.WelcomeView;
import kornell.gui.client.util.view.KornellNotification;

public class GenericWelcomeView extends Composite implements WelcomeView {
	interface MyUiBinder extends UiBinder<Widget, GenericWelcomeView> {
	}

	private static MyUiBinder uiBinder = GWT.create(MyUiBinder.class);

	@UiField
	FlowPanel coursesWrapper;
	@UiField
	FlowPanel pnlCourses;
	Button btnCoursesAll, btnCoursesInProgress, btnCoursesToStart, btnCoursesToAcquire, btnCoursesFinished;

	private KornellSession session;
	private PlaceController placeCtrl;
	private ViewFactory viewFactory;
	private EventBus bus;
	private static KornellConstants constants = GWT.create(KornellConstants.class);
	private Button selectedFilterButton;
	private ArrayList<IsWidget> widgets;

	private int classesCount;

	public GenericWelcomeView(ClientFactory clientFactory) {
		this.session = clientFactory.getKornellSession();
		this.placeCtrl = clientFactory.getPlaceController();
		this.viewFactory = clientFactory.getViewFactory();
		this.bus = clientFactory.getEventBus();
		initWidget(uiBinder.createAndBindUi(this));
		coursesWrapper.setVisible(false);

		initData();

		bus.addHandler(PlaceChangeEvent.TYPE, new PlaceChangeEvent.Handler() {
			@Override
			public void onPlaceChange(PlaceChangeEvent event) {
				if (event.getNewPlace() instanceof WelcomePlace) {
					initData();
				}
			}
		});
	}

	private void startPlaceBar() {
		if (widgets == null) {
			widgets = new ArrayList<IsWidget>();
			btnCoursesFinished = startButton(constants.finished(), widgets);
			btnCoursesToAcquire = startButton("Disponíveis", widgets);
			btnCoursesToStart = startButton(constants.toStart(), widgets);
			btnCoursesInProgress = startButton(constants.inProgress(), widgets);
			btnCoursesAll = startButton(constants.allClasses(), widgets);
			selectedFilterButton = btnCoursesAll;
		}
		viewFactory.getMenuBarView().setPlaceBarWidgets(widgets);
	}

	private Button startButton(String text, List<IsWidget> widgets) {
		Button button = new Button(text);
		button.addStyleName("btnPlaceBar");
		button.addClickHandler(new ClickHandler() {
			@Override
			public void onClick(ClickEvent event) {
				selectedFilterButton = (Button) event.getSource();
				initData();
			}
		});
		widgets.add(button);
		return button;
	}

	private void initData() {
		viewFactory.getMenuBarView().initPlaceBar(IconType.HOME, constants.homeTitle(), constants.homeDescription());
		session.courseClasses().getCourseClassesTO(new Callback<CourseClassesTO>() {
			@Override
			public void ok(CourseClassesTO courseClassesTO) {
				bus.fireEvent(new CourseClassesFetchedEvent(courseClassesTO));
				startPlaceBar();
				display(courseClassesTO);
			}
		});
	}

	private void display(final CourseClassesTO tos) {
		pnlCourses.clear();
		final int classesCount = tos.getCourseClasses().size();
		if (classesCount == 0) {
			coursesWrapper.setVisible(false);
			KornellNotification.show(constants.noClassesAvailable(), AlertType.WARNING, 8000);
		} else {
			coursesWrapper.setVisible(true);
		}

		prepareButtons(classesCount);
		prepareClassesPanel(tos);
	}

	private void prepareClassesPanel(final CourseClassesTO tos) {
		classesCount = tos.getCourseClasses().size();

		for (final CourseClassTO courseClassTO : tos.getCourseClasses()) {
			if (courseClassTO.getCourseClass().isInvisible())
				continue;

			final Teacher teacher = Teachers.of(courseClassTO);
			Student student = teacher.student(session.getCurrentUser());
			addPanelIfFiltered(btnCoursesAll, courseClassTO);
			if (student.isEnrolled()) {
				EnrollmentProgressDescription description = student.getEnrollmentProgress().getDescription();
				switch (description) {
				case completed:
					addPanelIfFiltered(btnCoursesFinished, courseClassTO);
					break;
				case inProgress:
					addPanelIfFiltered(btnCoursesInProgress, courseClassTO);
					break;
				case notStarted:
					addPanelIfFiltered(btnCoursesToStart, courseClassTO);
					break;
				}
			} else {
				addPanelIfFiltered(btnCoursesToAcquire, courseClassTO);
			}
		}
	}

	private void addPanelIfFiltered(Button button, CourseClassTO courseClassTO) {
		if (button.equals(selectedFilterButton)) {
			pnlCourses.add(new GenericCourseSummaryView(placeCtrl, courseClassTO, session));
		}
		if (classesCount > 3)
			button.setVisible(true);
	}

	private void prepareButtons(int classesCount) {
		refreshButtonSelection(btnCoursesAll);
		refreshButtonSelection(btnCoursesInProgress);
		refreshButtonSelection(btnCoursesToStart);
		refreshButtonSelection(btnCoursesToAcquire);
		refreshButtonSelection(btnCoursesFinished);
	}

	private void refreshButtonSelection(Button button) {
		button.setVisible(false);
		button.removeStyleName("btnAction");
		button.addStyleName("btnNotSelected");
		if (selectedFilterButton != null && selectedFilterButton.equals(button)) {
			button.addStyleName("btnAction");
			button.removeStyleName("btnNotSelected");
		}
	}

	@Override
	public void setPresenter(Presenter presenter) {
	}
}