/*
 * $Header$
 * $Revision:207563 $
 * $Date:2004-08-03 01:45:51 +1000 (Tue, 03 Aug 2004) $
 *
 * ====================================================================
 *
 * Copyright 1999-2002 The Apache Software Foundation 
 *
 * 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.apache.webdav.lib.util;

import java.io.IOException;
import java.io.Writer;

/**
 * XMLPrinter helper class.
 */
public class XMLPrinter {

	// -------------------------------------------------------------- Constants

	/**
	 * Opening tag.
	 */
	public static final int OPENING = 0;

	/**
	 * Closing tag.
	 */
	public static final int CLOSING = 1;

	/**
	 * Element with no content.
	 */
	public static final int NO_CONTENT = 2;

	// ----------------------------------------------------- Instance Variables

	/**
	 * Buffer.
	 */
	protected StringBuffer buffer = new StringBuffer();

	/**
	 * Writer.
	 */
	protected Writer writer = null;

	// ----------------------------------------------------------- Constructors

	/**
	 * Constructor.
	 */
	public XMLPrinter() {
	}

	/**
	 * Constructor.
	 */
	public XMLPrinter(Writer writer) {
		this.writer = writer;
	}

	// --------------------------------------------------------- Public Methods

	/**
	 * Retrieve generated XML.
	 * 
	 * @return String containing the generated XML
	 */
	public String toString() {
		return buffer.toString();
	}

	/**
	 * Write property to the XML.
	 * 
	 * @param namespace
	 *            Namespace
	 * @param namespaceInfo
	 *            Namespace info
	 * @param name
	 *            Property name
	 * @param value
	 *            Property value
	 */
	public void writeProperty(String namespace, String namespaceInfo,
			String name, String value, boolean cdata) {
		writeElement(namespace, namespaceInfo, name, OPENING);
		if (cdata)
			writeData(value);
		else
			writeText(value);
		writeElement(namespace, namespaceInfo, name, CLOSING);
	}

	/**
	 * Write property to the XML.
	 * 
	 * @param namespace
	 *            Namespace
	 * @param namespaceInfo
	 *            Namespace info
	 * @param name
	 *            Property name
	 * @param value
	 *            Property value
	 */
	public void writeProperty(String namespace, String namespaceInfo,
			String name, String value) {
		writeProperty(namespace, namespaceInfo, name, value, false);
	}

	/**
	 * Write property to the XML.
	 * 
	 * @param namespace
	 *            Namespace
	 * @param name
	 *            Property name
	 * @param value
	 *            Property value
	 */
	public void writeProperty(String namespace, String name, String value) {
		writeProperty(namespace, null, name, value);
	}

	/**
	 * Write property to the XML.
	 * 
	 * @param namespace
	 *            Namespace
	 * @param name
	 *            Property name
	 */
	public void writeProperty(String namespace, String name) {
		writeElement(namespace, name, NO_CONTENT);
	}

	/**
	 * Write an element.
	 * 
	 * @param name
	 *            Element name
	 * @param namespace
	 *            Namespace abbreviation
	 * @param type
	 *            Element type
	 */
	public void writeElement(String namespace, String name, int type) {
		writeElement(namespace, null, name, type);
	}

	public void writeElement(String namespace, String namespaceInfo,
			String name, int type) {
		writeElement(namespace, namespaceInfo, name, type, null);
	}

	/**
	 * Write an element.
	 * 
	 * @param namespace
	 *            Namespace abbreviation
	 * @param namespaceInfo
	 *            Namespace info
	 * @param name
	 *            Element name
	 * @param type
	 *            Element type
	 */
	public void writeElement(String namespace, String namespaceInfo,
			String name, int type, String definitionNamespace) {
		if (definitionNamespace == null)
			definitionNamespace = namespace;
		if ((namespace != null) && (namespace.length() > 0)) {
			switch (type) {
			case OPENING:
				if ((namespaceInfo != null) && (namespaceInfo.length() > 0)) {
					buffer.append("<" + namespace + ":" + name + " xmlns:"
							+ definitionNamespace + "=\"" + namespaceInfo
							+ "\">");
				} else {
					buffer.append("<" + namespace + ":" + name + ">");
				}
				break;
			case CLOSING:
				buffer.append("</" + namespace + ":" + name + ">");
				break;
			case NO_CONTENT:
			default:
				if ((namespaceInfo != null) && (namespaceInfo.length() > 0)) {
					buffer.append("<" + namespace + ":" + name + " xmlns:"
							+ definitionNamespace + "=\"" + namespaceInfo
							+ "\"/>");
				} else {
					buffer.append("<" + namespace + ":" + name + "/>");
				}
				break;
			}
		} else {
			switch (type) {
			case OPENING:
				if ((namespaceInfo != null) && (namespaceInfo.length() > 0)) {
					buffer.append("<" + name + " xmlns=\"" + namespaceInfo
							+ "\">");
				} else {
					buffer.append("<" + name + ">");
				}
				break;
			case CLOSING:
				buffer.append("</" + name + ">");
				break;
			case NO_CONTENT:
			default:
				if ((namespaceInfo != null) && (namespaceInfo.length() > 0)) {
					buffer.append("<" + name + " xmlns=\"" + namespaceInfo
							+ "\"/>");
				} else {
					buffer.append("<" + name + "/>");
				}
				break;
			}
		}
	}

	/**
	 * Write text.
	 * 
	 * @param text
	 *            Text to append
	 */
	public void writeText(String text) {
		buffer.append(text);
	}

	/**
	 * Write data.
	 * 
	 * @param data
	 *            Data to append
	 */
	public void writeData(String data) {
		buffer.append("<![CDATA[");
		buffer.append(data);
		buffer.append("]]>");
	}

	/**
	 * Write XML Header.
	 */
	public void writeXMLHeader() {
		buffer.append("<?xml version=\"1.0\" encoding=\"utf-8\" ?>");
	}

	/**
	 * Send data and reinitializes buffer.
	 */
	public void sendData() throws IOException {
		if (writer != null) {
			writer.write(buffer.toString());
			buffer = new StringBuffer();
		}
	}

}