/**************************************************************
 * 
 * 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 com.sun.star.form.binding.*;

/**
 *
 * @author  fs@openoffice.org
 */
public class DateValidator extends ControlValidator
{

    /** Creates a new instance of NumericValidator */
    public DateValidator( )
    {
    }

    public String explainInvalid( Object Value )
    {
        try
        {
            if ( isVoid( Value ) )
                return "empty input";

            com.sun.star.util.Date dateValue = (com.sun.star.util.Date)Value;
            if ( isDedicatedInvalidDate( dateValue ) )
                return "this is no valid date";

            if ( !isNextMonthsDate( dateValue ) )
                return "date must denote a day in the current month";
        }
        catch( java.lang.Exception e )
        {
            return "oops. What did you enter for this to happen?";
        }
        return "";
    }

    public boolean isValid( Object Value )
    {
        try
        {
            if ( isVoid( Value ) )
                return false;

            com.sun.star.util.Date dateValue = (com.sun.star.util.Date)
                com.sun.star.uno.AnyConverter.toObject(
                    com.sun.star.util.Date.class, Value);
            if ( isDedicatedInvalidDate( dateValue ) )
                return false;

            if ( !isNextMonthsDate( dateValue ) )
                return false;
            return true;
        }
        catch( java.lang.Exception e )
        {
            e.printStackTrace( System.err );
        }
        return false;
    }

    private boolean isDedicatedInvalidDate( com.sun.star.util.Date dateValue )
    {
        return ( dateValue.Day == 0 ) && ( dateValue.Month == 0 ) && ( dateValue.Year == 0 );
    }

    private boolean isNextMonthsDate( com.sun.star.util.Date dateValue )
    {
        int overallMonth = dateValue.Year * 12 + dateValue.Month - 1;

        int todaysMonth = new java.util.Date().getMonth();
        int todaysYear = new java.util.Date().getYear() + 1900;
        int todaysOverallMonth = todaysYear * 12 + todaysMonth;

        return overallMonth == todaysOverallMonth;
    }
}