/*
 *  eXist Open Source Native XML Database
 *  Copyright (C) 2010 The eXist Project
 *  http://exist-db.org
 *
 *  This program is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public License
 *  as published by the Free Software Foundation; either version 2
 *  of the License, or (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, write to the Free Software
 *  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
 *
 *  $Id$
 */
package org.exist.ant;

import org.apache.tools.ant.BuildException;
import org.apache.tools.ant.Project;
import org.apache.tools.ant.PropertyHelper;

import org.xmldb.api.DatabaseManager;
import org.xmldb.api.base.Collection;
import org.xmldb.api.base.ResourceSet;
import org.xmldb.api.base.XMLDBException;
import org.xmldb.api.modules.XPathQueryService;

/**
 * Ant task to execute an XQuery.
 * 
 * The query is either passed as nested text in the element,
 * or via an attribute "query".
 * 
 * Please note that the task doesn't output the query results.
 * 
 * @author wolf
 */
public class XMLDBQueryTask extends AbstractXMLDBTask {

    private String query = null;
    private String text = null;

    /* (non-Javadoc)
     * @see org.apache.tools.ant.Task#execute()
     */
    public void execute() throws BuildException {
        if (uri == null) {
            throw new BuildException("you have to specify an XMLDB collection URI");
        }

        if (text != null) {
            PropertyHelper helper = PropertyHelper.getPropertyHelper(getProject());
            query = helper.replaceProperties(null, text, null);
        }

        if (query == null) {
            throw new BuildException("you have to specify a query");
        }

        log("XQuery is:\n" + query, org.apache.tools.ant.Project.MSG_DEBUG);

        registerDatabase();
        try {
            Collection collection = DatabaseManager.getCollection(uri, user, password);

            if (collection == null) {
                String msg = "Collection " + uri + " could not be found.";
                if (failonerror) {
                    throw new BuildException(msg);
                } else {
                    log(msg, Project.MSG_ERR);
                }

            } else {
                XPathQueryService service = (XPathQueryService) collection.getService("XPathQueryService", "1.0");
                ResourceSet results = service.query(query);
                log("Found " + results.getSize());
            }
            
        } catch (XMLDBException e) {
            String msg = "XMLDB exception caught while executing query: " + e.getMessage();
            if (failonerror) {
                throw new BuildException(msg, e);
            } else {
                log(msg, e, Project.MSG_ERR);
            }
        }
    }

    /**
     * @param query
     */
    public void setQuery(String query) {
        this.query = query;
    }

    public void addText(String text) {
        this.text = text;
    }
}