/**
 *  Copyright 2012-2017 Gunnar Morling (http://www.gunnarmorling.de/)
 *  and/or other contributors as indicated by the @authors tag. See the
 *  copyright.txt file in the distribution for a full listing of all
 *  contributors.
 *
 *  Licensed 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.mapstruct.ap.internal.conversion;

import static org.mapstruct.ap.internal.util.Collections.asSet;

import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.List;
import java.util.Set;

import org.mapstruct.ap.internal.model.HelperMethod;
import org.mapstruct.ap.internal.model.common.ConversionContext;
import org.mapstruct.ap.internal.model.common.Type;

/**
 * Conversion between {@link BigDecimal} and {@link String}.
 *
 * @author Gunnar Morling
 */
public class BigDecimalToStringConversion extends AbstractNumberToStringConversion  {

    public BigDecimalToStringConversion() {
        super( true );
    }

    @Override
    public String getToExpression(ConversionContext conversionContext) {
        if ( requiresDecimalFormat( conversionContext ) ) {
            StringBuilder sb = new StringBuilder();
            appendDecimalFormatter( sb, conversionContext );
            sb.append( ".format( <SOURCE> )" );
            return sb.toString();
        }
        else {
            return "<SOURCE>.toString()";
        }
    }

    @Override
    public String getFromExpression(ConversionContext conversionContext) {
        if ( requiresDecimalFormat( conversionContext ) ) {
            StringBuilder sb = new StringBuilder();
            sb.append( "(BigDecimal) " );
            appendDecimalFormatter( sb, conversionContext );
            sb.append( ".parse( <SOURCE> )" );
            return sb.toString();
        }
        else {
           return "new BigDecimal( <SOURCE> )";
        }
    }

    @Override
    protected Set<Type> getFromConversionImportTypes(ConversionContext conversionContext) {
        return asSet( conversionContext.getTypeFactory().getType( BigDecimal.class ) );
    }

    @Override
    public List<HelperMethod> getRequiredHelperMethods(ConversionContext conversionContext) {
        List<HelperMethod> helpers = new ArrayList();
        if ( conversionContext.getNumberFormat() != null ) {
            helpers.add( new CreateDecimalFormat( conversionContext.getTypeFactory() ) );
        }
        return helpers;
    }

    private void appendDecimalFormatter(StringBuilder sb, ConversionContext conversionContext) {
        sb.append( "createDecimalFormat( " );
        if ( conversionContext.getNumberFormat() != null ) {
            sb.append( "\"" );
            sb.append( conversionContext.getNumberFormat() );
            sb.append( "\"" );
        }

        sb.append( " )" );
    }

}