/* ====================================================================
   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.
==================================================================== */

namespace HH.WMS.Utils.NPOI.SS.Formula.PTG
{
    using System;
    using System.Text;

    /**
     * Less than operator PTG "<". The SID is taken from the 
     * Openoffice.orgs Documentation of the Excel File Format,
     * Table 3.5.7
     * @author Cameron Riley (criley at ekmail.com)
     */
    public class LessThanPtg : ValueOperatorPtg
    {
        /** the sid for the less than operator as hex */
        public const byte sid = 0x09;

        /** identifier for LESS THAN char */
        private static String LESSTHAN = "<";

        public static ValueOperatorPtg instance = new LessThanPtg();

        private LessThanPtg()
        {
            // enforce singleton
        }

        protected override byte Sid
        {
            get { return sid; }
        }

        /**
         * Get the number of operands for the Less than operator
         * @return int the number of operands
         */
        public override int NumberOfOperands
        {
            get { return 2; }
        }

        /** 
        * Implementation of method from OperationsPtg
        * @param operands a String array of operands
        * @return String the Formula as a String
        */
        public override String ToFormulaString(String[] operands)
        {
            StringBuilder buffer = new StringBuilder();
            buffer.Append(operands[0]);
            buffer.Append(LESSTHAN);
            buffer.Append(operands[1]);
            return buffer.ToString();
        }
    }
}