001/*
002 *  Copyright 2010 Anyware Services
003 *
004 *  Licensed under the Apache License, Version 2.0 (the "License");
005 *  you may not use this file except in compliance with the License.
006 *  You may obtain a copy of the License at
007 *
008 *      http://www.apache.org/licenses/LICENSE-2.0
009 *
010 *  Unless required by applicable law or agreed to in writing, software
011 *  distributed under the License is distributed on an "AS IS" BASIS,
012 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 *  See the License for the specific language governing permissions and
014 *  limitations under the License.
015 */
016package org.ametys.plugins.repository.query.expression;
017
018import org.ametys.plugins.repository.RepositoryConstants;
019
020/**
021 * Constructs an {@link Expression} testing the existence of a metadata.
022 */
023public class MetadataExpression implements Expression
024{
025    private String _metadata;
026    private String _path;
027    private ExpressionContext _context;
028
029    /**
030     * Creates the comparison Expression.
031     * @param metadata the metadata name
032     */
033    public MetadataExpression(String metadata)
034    {
035        this(metadata, ExpressionContext.newInstance());
036    }
037    
038    /**
039     * Creates the comparison Expression.
040     * @param metadata the metadata name
041     * @param context the context of the expression
042     */
043    public MetadataExpression(String metadata, ExpressionContext context)
044    {
045        int index = metadata.lastIndexOf('/');
046        boolean isComposite = index != -1;
047        _path = isComposite ? metadata.substring(0, index) : null;
048        _metadata = isComposite ? metadata.substring(index + 1) : metadata;
049        _context = context;
050    }
051    
052    public String build()
053    {
054        StringBuilder buff = new StringBuilder();
055        String repositoryPrefix = _context.internal() ? RepositoryConstants.NAMESPACE_PREFIX_INTERNAL : RepositoryConstants.NAMESPACE_PREFIX;
056        
057        if (_context.unversioned())
058        {
059            buff.append(RepositoryConstants.NAMESPACE_PREFIX_INTERNAL).append(":unversioned/");
060        }
061        if (_path != null)
062        {
063            String[] parts = _path.split("/");
064            for (String part : parts)
065            {
066                if ("*".equals(part))
067                {
068                    buff.append(part).append('/');
069                }
070                else
071                {
072                    buff.append(repositoryPrefix).append(':').append(part).append('/');
073                }
074                
075            }
076        }
077        buff.append('@').append(repositoryPrefix).append(':').append(_metadata);
078        
079        return buff.toString();
080    }
081}