    001// Copyright 2013 The Apache Software Foundation
    002//
    003// Licensed under the Apache License, Version 2.0 (the "License");
    004// you may not use this file except in compliance with the License.
    005// You may obtain a copy of the License at
    006//
    007// http://www.apache.org/licenses/LICENSE-2.0
    008//
    009// Unless required by applicable law or agreed to in writing, software
    010// distributed under the License is distributed on an "AS IS" BASIS,
    011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    012// See the License for the specific language governing permissions and
    013// limitations under the License.
    014
    015package org.apache.tapestry5.corelib.components;
    016
    017import org.apache.tapestry5.ComponentResources;
    018import org.apache.tapestry5.MarkupWriter;
    019import org.apache.tapestry5.annotations.Import;
    020import org.apache.tapestry5.annotations.Parameter;
    021import org.apache.tapestry5.annotations.SupportsInformalParameters;
    022import org.apache.tapestry5.ioc.annotations.Inject;
    023import org.apache.tapestry5.services.DateUtilities;
    024
    025import java.util.Date;
    026
    027/**
    028 * Used to present an interval value using Moment.js's from() or fromNow() functions. The interval
    029 * is determined in terms of a start and end date; either (but not both) may be omitted, in which
    030 * case the client will dynamically update the element.  In that case, the value will live update, approximately every second.
    031 * <p/>
    032 * This component will render an empty element. The element will match the template element,
    033 * or a "span" if the template did not provide an element. Informal parameters will be rendered
    034 * into the element.
    035 * <p/>
    036 * When the end date is after the start date, the rendered text will be prefixed with "in".
    037 * When the end date precedes the start date, the rendered text will be suffixed with "ago".
    038 * The plain parameter is used to turn off the prefix or suffix.
    039 *
    040 * @tapestrydoc
    041 * @see LocalDate
    042 * @since 5.4
    043 */
    044@SupportsInformalParameters
    045@Import(module = "t5/core/time-interval")
    046public class TimeInterval
    047{
    048    /**
    049     * The start date for the interval. If omitted, the start time is considered "now" and will automatically
    050     * update in the browser.
    051     */
    052    @Parameter
    053    Date start;
    054
    055    /**
    056     * The end date for the interval. If omitted, the end time is considered "now" and will update automatically
    057     * in the browser.
    058     */
    059    @Parameter()
    060    Date end;
    061
    062    /**
    063     * If true, then output is plain: no "in" prefix or "ago" suffix.
    064     */
    065    @Parameter
    066    boolean plain;
    067
    068    @Inject
    069    ComponentResources resources;
    070
    071    @Inject
    072    DateUtilities dateUtilities;
    073
    074    private String toISO(Date date)
    075    {
    076        return date == null ? null : dateUtilities.formatISO8601(date);
    077    }
    078
    079    boolean beginRender(MarkupWriter writer)
    080    {
    081        writer.element(resources.getElementName("span"),
    082                // Trigger the client-side logic:
    083                "data-timeinterval", "true",
    084                "data-timeinterval-start", toISO(start),
    085                "data-timeinterval-end", toISO(end));
    086
    087        if (plain)
    088        {
    089            writer.attributes("data-timeinterval-plain", true);
    090        }
    091
    092        resources.renderInformalParameters(writer);
    093
    094        writer.end();
    095
    096        // Skip the body regardless.
    097        return false;
    098    }
    099
    100}