/* ====================================================================
   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.
==================================================================== */
package org.apache.poi.ss.formula.functions;

import org.apache.poi.ss.formula.SheetNameFormatter;
import org.apache.poi.ss.formula.eval.ErrorEval;
import org.apache.poi.ss.formula.eval.EvaluationException;
import org.apache.poi.ss.formula.eval.MissingArgEval;
import org.apache.poi.ss.formula.eval.OperandResolver;
import org.apache.poi.ss.formula.eval.StringEval;
import org.apache.poi.ss.formula.eval.ValueEval;
import org.apache.poi.ss.util.CellReference;

/**
 * Creates a text reference as text, given specified row and column numbers.
 *
 * @author Aniket Banerjee (banerjee@google.com)
 */
public class Address implements Function {
    public static final int REF_ABSOLUTE = 1;
    public static final int REF_ROW_ABSOLUTE_COLUMN_RELATIVE = 2;
    public static final int REF_ROW_RELATIVE_RELATIVE_ABSOLUTE = 3;
    public static final int REF_RELATIVE = 4;

    public ValueEval evaluate(ValueEval[] args, int srcRowIndex,
                              int srcColumnIndex) {
        if(args.length < 2 || args.length > 5) {
            return ErrorEval.VALUE_INVALID;
        }
        try {
            boolean pAbsRow, pAbsCol;

            int row =  (int)NumericFunction.singleOperandEvaluate(args[0], srcRowIndex, srcColumnIndex);
            int col =  (int)NumericFunction.singleOperandEvaluate(args[1], srcRowIndex, srcColumnIndex);

            int refType;
            if(args.length > 2){
                refType = (int)NumericFunction.singleOperandEvaluate(args[2], srcRowIndex, srcColumnIndex);
            } else {
                refType = REF_ABSOLUTE;
            }
            switch (refType){
                case REF_ABSOLUTE:
                    pAbsRow = true;
                    pAbsCol = true;
                    break;
                case REF_ROW_ABSOLUTE_COLUMN_RELATIVE:
                    pAbsRow = true;
                    pAbsCol = false;
                    break;
                case REF_ROW_RELATIVE_RELATIVE_ABSOLUTE:
                    pAbsRow = false;
                    pAbsCol = true;
                    break;
                case REF_RELATIVE:
                    pAbsRow = false;
                    pAbsCol = false;
                    break;
                default:
                    throw new EvaluationException(ErrorEval.VALUE_INVALID);
            }

            boolean a1;
            if(args.length > 3){
                ValueEval ve = OperandResolver.getSingleValue(args[3], srcRowIndex, srcColumnIndex);
                // TODO R1C1 style is not yet supported
				a1 = ve == MissingArgEval.instance ? true : OperandResolver
						.coerceValueToBoolean(ve, false).booleanValue();
            } else {
                a1 = true;
            }

            String sheetName;
            if(args.length == 5){
                ValueEval ve = OperandResolver.getSingleValue(args[4], srcRowIndex, srcColumnIndex);
                sheetName = ve == MissingArgEval.instance ? null : OperandResolver.coerceValueToString(ve);
            } else {
                sheetName = null;
            }

            CellReference ref = new CellReference(row - 1, col - 1, pAbsRow, pAbsCol);
            StringBuffer sb = new StringBuffer(32);
            if(sheetName != null) {
                SheetNameFormatter.appendFormat(sb, sheetName);
                sb.append('!');
            }
            sb.append(ref.formatAsString());

            return new StringEval(sb.toString());

        } catch (EvaluationException e){
            return e.getErrorEval();
        }
    }
}
