package org.apache.maven.model.interpolation;

/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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.
 */

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.GregorianCalendar;
import java.util.Properties;
import java.util.TimeZone;

public class MavenBuildTimestamp
{
    // ISO 8601-compliant timestamp for machine readability
    public static final String DEFAULT_BUILD_TIMESTAMP_FORMAT = "yyyy-MM-dd'T'HH:mm:ss'Z'";

    public static final String BUILD_TIMESTAMP_FORMAT_PROPERTY = "maven.build.timestamp.format";

    public static final TimeZone DEFAULT_BUILD_TIME_ZONE = TimeZone.getTimeZone( "Etc/UTC" );

    private String formattedTimestamp;

    public MavenBuildTimestamp()
    {
        this( new Date() );
    }

    public MavenBuildTimestamp( Date time )
    {
        this( time, DEFAULT_BUILD_TIMESTAMP_FORMAT );
    }

    public MavenBuildTimestamp( Date time, Properties properties )
    {
        this( time, properties != null ? properties.getProperty( BUILD_TIMESTAMP_FORMAT_PROPERTY ) : null );
    }

    public MavenBuildTimestamp( Date time, String timestampFormat )
    {
        if ( timestampFormat == null )
        {
            timestampFormat = DEFAULT_BUILD_TIMESTAMP_FORMAT;
        }
        if ( time == null )
        {
            time = new Date();
        }
        SimpleDateFormat dateFormat = new SimpleDateFormat( timestampFormat );
        dateFormat.setCalendar( new GregorianCalendar() );
        dateFormat.setTimeZone( DEFAULT_BUILD_TIME_ZONE );
        formattedTimestamp = dateFormat.format( time );
    }

    public String formattedTimestamp()
    {
        return formattedTimestamp;
    }
}
