/*
 * Zed Attack Proxy (ZAP) and its related class files.
 *
 * ZAP is an HTTP/HTTPS proxy for assessing web application security.
 *
 * Copyright 2011 The Zed Attack Proxy Team
 *
 * 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.zaproxy.zap.utils;

import java.io.File;
import java.net.URL;

import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;

import org.apache.commons.configuration.ConfigurationException;
import org.apache.commons.configuration.XMLConfiguration;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
import org.xml.sax.helpers.DefaultHandler;

/**
 * A {@code XMLConfiguration} with character encoding always set to UTF-8 and
 * delimiter parsing always disabled.
 * <p>
 * <strong>Note:</strong> This class should be used, <i>always</i>, to
 * read/write from/to the configurations' file used by ZAP, this way there
 * shouldn't be any problems with character encodings.
 * </p>
 * 
 * @see #setDelimiterParsingDisabled(boolean)
 * @see XMLConfiguration
 */
public class ZapXmlConfiguration extends XMLConfiguration {

	private static final long serialVersionUID = -8598525138011232529L;

	/**
	 * Creates a new instance of {@code ZapXmlConfiguration}.
	 */
	public ZapXmlConfiguration() {
		super();

		super.setEncoding("UTF-8");
		super.setDelimiterParsingDisabled(true);
	}

	/**
	 * Creates a new instance of {@code ZapXmlConfiguration}. The configuration
	 * is loaded from the file with the specified {@code fileName}.
	 * 
	 * @param fileName
	 *            the name of the file to load
	 * @throws ConfigurationException
	 *             if loading the configuration fails
	 */
	public ZapXmlConfiguration(String fileName) throws ConfigurationException {
		this();
		setFileName(fileName);
		load();
	}

	/**
	 * Creates a new instance of {@code ZapXmlConfiguration}. The configuration
	 * is loaded from the specified {@code file}.
	 * 
	 * @param file
	 *            the file that has the configuration
	 * @throws ConfigurationException
	 *             if loading the configuration fails
	 */
	public ZapXmlConfiguration(File file) throws ConfigurationException {
		this();
		setFile(file);
		load();
	}

	@Override
	protected DocumentBuilder createDocumentBuilder() throws ParserConfigurationException {
		DocumentBuilderFactory factory = XmlUtils.newXxeDisabledDocumentBuilderFactory();

		// Same behaviour as base method:
		if (isValidating()) {
			factory.setValidating(true);
			if (isSchemaValidation()) {
				factory.setNamespaceAware(true);
				factory.setAttribute(
						"http://java.sun.com/xml/jaxp/properties/schemaLanguage",
						"http://www.w3.org/2001/XMLSchema");
			}
		}

		DocumentBuilder result = factory.newDocumentBuilder();
		result.setEntityResolver(getEntityResolver());

		if (isValidating()) {
			result.setErrorHandler(new DefaultHandler() {

				@Override
				public void error(SAXParseException ex) throws SAXException {
					throw ex;
				}
			});
		}
		return result;
	}

	/**
	 * Creates a new instance of {@code ZapXmlConfiguration}. The configuration
	 * is loaded from the specified {@code url}.
	 * 
	 * @param url
 	 *            the URL
	 * @throws ConfigurationException
	 *             if loading the configuration fails
	 */
	public ZapXmlConfiguration(URL url) throws ConfigurationException {
		this();
		setURL(url);
		load();
	}

	/**
	 * Calling this method has <strong>no</strong> effect. The character
	 * encoding used is always the same, UTF-8.
	 */
	@Override
	public void setEncoding(String encoding) {
		// Always uses UTF-8
	}

	/**
	 * Calling this method has <strong>no</strong> effect. The delimiter parsing
	 * is always disabled.
	 * 
	 * @see #setDelimiterParsingDisabled(boolean)
	 */
	@Override
	public void setListDelimiter(char listDelimiter) {
		// Always use the default character, as calling
		// setDelimiterParsingDisabled as no effect, there is no need to change
		// the character.
	}

	/**
	 * Calling this method has <strong>no</strong> effect. The delimiter parsing
	 * is always disabled.
	 */
	@Override
	public void setDelimiterParsingDisabled(boolean delimiterParsingDisabled) {
		// Always disabled.
	}
}