package eu.future.earth.gwt.client.date.picker;

import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;

import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.event.shared.HandlerRegistration;
import com.google.gwt.i18n.client.DateTimeFormat;
import com.google.gwt.user.client.ui.Grid;
import com.google.gwt.user.client.ui.HorizontalPanel;
import com.google.gwt.user.client.ui.Image;
import com.google.gwt.user.client.ui.Label;

import eu.future.earth.gwt.client.FtrGwtDatePickerCss;
import eu.future.earth.gwt.client.date.FtrGwtResources;
import eu.future.earth.gwt.client.date.picker.DateSelectEvent.DateSelectEventActions;

public class MonthNavigator extends Grid implements ClickHandler, HasDateSelectHandlers {

	private Image prev = new Image(FtrGwtResources.IMAGES.cal_prev());

	private Image next = new Image(FtrGwtResources.IMAGES.cal_next());

	private Label label = new Label("");

	public MonthNavigator(boolean setStyle) {
		super(1, 3);
		this.setWidget(0, 0, prev);
		this.setWidget(0, 1, label);
		this.setWidget(0, 2, next);

		this.getCellFormatter().setWidth(0, 0, "10%");
		this.getCellFormatter().setWidth(0, 1, "80%");
		this.getCellFormatter().setWidth(0, 2, "10%");

		this.getCellFormatter().setHorizontalAlignment(0, 1, HorizontalPanel.ALIGN_CENTER);
		this.getCellFormatter().setHorizontalAlignment(0, 2, HorizontalPanel.ALIGN_RIGHT);

		this.setWidth("100%");
		this.setHeight("18px");

		next.addClickHandler(this);
		prev.addClickHandler(this);
		label.addClickHandler(this);
		prev.setStyleName(FtrGwtDatePickerCss.IMAGE_BUTTON);
		next.setStyleName(FtrGwtDatePickerCss.IMAGE_BUTTON);
		if (setStyle) {
			this.setStyleName(FtrGwtDatePickerCss.MONTH_NAV);
		}
		super.setStyleName(FtrGwtDatePickerCss.MONTH_SELECT);
		label.setText(getDisplayText());
	}

	private DateTimeFormat formatter = DateTimeFormat.getFormat("yyyy MMMM"); // NOPMD;

	public String getDisplayText() {
		return formatter.format(current.getTime());
	}

	private Calendar current = new GregorianCalendar();

	public void setSelectedDate(Date newDate) {
		current.setTime(newDate);
		label.setText(getDisplayText());
	}

	public HandlerRegistration addDateSelectEventHandler(DateSelectListener handler) {
		return addHandler(handler, DateSelectEvent.getType());
	}

	public void onClick(ClickEvent event) {
		if (event.getSource() == prev) {
			current.add(Calendar.MONTH, -1);
			label.setText(getDisplayText());
			DateSelectEvent.fire(this, current.getTime(), DateSelectEventActions.NAVIGATE_MONTH);
		}

		if (event.getSource() == next) {
			current.add(Calendar.MONTH, 1);
			label.setText(getDisplayText());
			DateSelectEvent.fire(this, current.getTime(), DateSelectEventActions.NAVIGATE_MONTH);
		}
		if (event.getSource() == label) {
			current.setTime(new Date());
			label.setText(getDisplayText());
			DateSelectEvent.fire(this, current.getTime(), DateSelectEventActions.SELECT_NEW_MONTH);
		}

	}

	public Date getSelected() {
		return current.getTime();
	}

}