/*
 * Copyright (C) 2013 Red Hat, Inc. and/or its affiliates.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *       http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.jboss.errai.demo.jpa.client.local;

import com.google.gwt.event.dom.client.ClickEvent;
import com.google.gwt.event.dom.client.ClickHandler;
import com.google.gwt.user.client.ui.Grid;
import com.google.gwt.user.client.ui.HTMLTable.CellFormatter;
import com.google.gwt.user.client.ui.PushButton;
import com.google.gwt.user.datepicker.client.CalendarModel;
import com.google.gwt.user.datepicker.client.MonthSelector;

/**
 * A simple {@link MonthSelector} used for the default date picker. Not extensible as we wish to evolve it freely over time.
 * <p>
 * Taken from the GWT discussion group: https://groups.google.com/group
 * /google-web-toolkit/browse_thread/thread/5feaef678ae7cb8a/446322e1fc6bc956
 *
 * @author Danny Goovaerts
 */
class MonthAndYearSelector extends MonthSelector {
    private static String BASE_NAME = "datePicker";
    private PushButton backwards;
    private PushButton forwards;
    private PushButton backwardsYear;
    private PushButton forwardsYear;
    private Grid grid;
    private int previousYearColumn = 0;
    private int previousMonthColumn = 1;
    private int monthColumn = 2;
    private int nextMonthColumn = 3;
    private int nextYearColumn = 4;
    private CalendarModel model;
    private DatePickerWithYearSelector picker;

    public void setModel(CalendarModel model) {
        this.model = model;
    }

    public void setPicker(DatePickerWithYearSelector picker) {
        this.picker = picker;
    }

    @Override
    protected void refresh() {
        String formattedMonth = getModel().formatCurrentMonth();
        grid.setText(0, monthColumn, formattedMonth);
    }

    @Override
    protected void setup() {
        // Set up backwards.
        backwards = new PushButton();
        backwards.addClickHandler(new ClickHandler() {
            @Override
            public void onClick(ClickEvent event) {
                addMonths(-1);
            }
        });
        backwards.getUpFace().setHTML("‹");
        backwards.setStyleName(BASE_NAME + "PreviousButton");
        forwards = new PushButton();
        forwards.getUpFace().setHTML("›");
        forwards.setStyleName(BASE_NAME + "NextButton");
        forwards.addClickHandler(new ClickHandler() {
            @Override
            public void onClick(ClickEvent event) {
                addMonths(+1);
            }
        });
        // Set up backwards year
        backwardsYear = new PushButton();
        backwardsYear.addClickHandler(new ClickHandler() {
            @Override
            public void onClick(ClickEvent event) {
                addMonths(-12);
            }
        });
        backwardsYear.getUpFace().setHTML("«");
        backwardsYear.setStyleName(BASE_NAME + "PreviousButton");
        forwardsYear = new PushButton();
        forwardsYear.getUpFace().setHTML("»");
        forwardsYear.setStyleName(BASE_NAME + "NextButton");
        forwardsYear.addClickHandler(new ClickHandler() {
            @Override
            public void onClick(ClickEvent event) {
                addMonths(+12);
            }
        });
        // Set up grid.
        grid = new Grid(1, 5);
        grid.setWidget(0, previousYearColumn, backwardsYear);
        grid.setWidget(0, previousMonthColumn, backwards);
        grid.setWidget(0, nextMonthColumn, forwards);
        grid.setWidget(0, nextYearColumn, forwardsYear);
        CellFormatter formatter = grid.getCellFormatter();
        formatter.setStyleName(0, monthColumn, BASE_NAME + "Month");
        formatter.setWidth(0, previousYearColumn, "1");
        formatter.setWidth(0, previousMonthColumn, "1");
        formatter.setWidth(0, monthColumn, "100%");
        formatter.setWidth(0, nextMonthColumn, "1");
        formatter.setWidth(0, nextYearColumn, "1");
        grid.setStyleName(BASE_NAME + "MonthSelector");
        initWidget(grid);
    }

    @Override
    public void addMonths(int numMonths) {
        model.shiftCurrentMonth(numMonths);
        picker.refreshComponents();
    }
}