/*
 * Copyright 2016 Red Hat, Inc. and/or its affiliates.
 *
 * 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.kie.dmn.backend.marshalling.v1_1.xstream;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

import javax.xml.XMLConstants;
import javax.xml.namespace.QName;

import org.kie.dmn.model.v1_1.Context;
import org.kie.dmn.model.v1_1.DecisionTable;
import org.kie.dmn.model.v1_1.Expression;
import org.kie.dmn.model.v1_1.FunctionDefinition;
import org.kie.dmn.model.v1_1.Invocation;
import org.kie.dmn.model.v1_1.LiteralExpression;
import org.kie.dmn.model.v1_1.Relation;

public class MarshallingUtils {
    private final static Pattern QNAME_PAT = Pattern.compile( "((\\{([^\\}]*)\\})?([^:]*):)?(.*)" );

    public static QName parseQNameString(String qns) {
        if ( qns != null ) {
            Matcher m = QNAME_PAT.matcher( qns );
            if ( m.matches() && m.group( 4 ) != null ) {
                return new QName( m.group( 3 ), m.group( 5 ), m.group( 4 ) );
            } else {
                return new QName( qns );
            }
        } else {
            return null;
        }
    }
    
    public static String formatQName(QName qname) {
        if ( !XMLConstants.DEFAULT_NS_PREFIX.equals(qname.getPrefix()) ) {
            return qname.getPrefix() + ":" + qname.getLocalPart();
        } else {
            return qname.toString();
        }
    }

    /**
     * TODO missing what-if in the case of List..
     */
    public static String defineExpressionNodeName(Expression e) {
        String nodeName = "expression";
        if (e instanceof Context) {
            nodeName = "context";
        } else if (e instanceof DecisionTable) {
            nodeName = "decisionTable";
        } else if (e instanceof FunctionDefinition) {
            nodeName = "functionDefinition";
        } else if (e instanceof Invocation) {
            nodeName = "invocation";
        } else if (e instanceof LiteralExpression) {
            nodeName = "literalExpression";
        } else if (e instanceof Relation) {
            nodeName = "relation";
        }
        return nodeName;
    }
}