/*
    * Created on Dec 29, 2004
    * 
    *   Magic-Project is a turn based strategy simulator
    *   Copyright (C) 2003-2007 Fabrice Daugan
    *
    *   This program is free software; you can redistribute it and/or modify it 
    * under the terms of the GNU 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 General Public License for more 
   * details.
   *
   *   You should have received a copy of the GNU General Public License along  
   * with this program; if not, write to the Free Software Foundation, Inc., 
   * 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
   */
  package net.sf.magicproject.xml;
  
  import java.io.File;
  import java.io.IOException;
  import java.io.InputStream;
  import java.io.PrintWriter;
  import java.net.URI;
  import java.net.URISyntaxException;
  import java.util.AbstractList;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.Map;
  import java.util.Stack;
  
  import javax.xml.parsers.SAXParser;
  import javax.xml.parsers.SAXParserFactory;
  
  import net.sf.magicproject.token.IdConst;
  import net.sf.magicproject.tools.MToolKit;
  
  import org.apache.commons.lang.StringUtils;
  import org.xml.sax.Attributes;
  import org.xml.sax.ContentHandler;
  import org.xml.sax.InputSource;
  import org.xml.sax.SAXException;
  import org.xml.sax.SAXParseException;
  import org.xml.sax.XMLReader;
  import org.xml.sax.helpers.DefaultHandler;
  
  /***
   * XML Parser wrapper. This class wraps any standard JAXP1.1 parser with
   * convieniant error and entity handlers and a mini dom-like document tree.
   * <P>
   * By default, the parser is created as a validating parser. This can be changed
   * by setting the "org.mortbay.xml.XmlParser.NotValidating" system property to
   * true.
   * 
   * @version $Id$
   * @author Greg Wilkins (gregw)
   */
  public class XmlParser {
  
  	/***
  	 * Constructor.
  	 */
  	public XmlParser() {
  		try {
  			SAXParserFactory factory = SAXParserFactory.newInstance();
  			factory.setNamespaceAware(true);
  			factory.setValidating(XmlConfiguration.validationOn);
  			parser = factory.newSAXParser();
  			if (XmlConfiguration.validationOn) {
  				parser.setProperty(JAXP_SCHEMA_LANGUAGE, W3C_XML_SCHEMA);
  				parser.setProperty(JAXP_SCHEMA_SOURCE, MToolKit.getFile(MP_XML_SCHEMA));
  			}
  		} catch (Exception e) {
  			System.out.println(e);
  			throw new InternalError(e.toString());
  		}
  	}
  
  	/***
  	 * @param source
  	 *          the document source.
  	 * @return the node of document.
  	 * @throws IOException
  	 *           error while opening the stream.
  	 * @throws SAXException
  	 *           error while parsing.
  	 */
  	public synchronized Node parse(InputSource source) throws IOException,
  			SAXException {
  		Handler handler = new Handler();
  		XMLReader reader = parser.getXMLReader();
  		reader.setContentHandler(handler);
  		reader.setErrorHandler(handler);
  		reader.setEntityResolver(handler);
  		parser.parse(source, handler);
  		if (handler.error != null) {
 			throw handler.error;
 		}
 		Node doc = (Node) handler.top.get(0);
 		handler.clear();
 		return doc;
 	}
 
 	/***
 	 * Parse string URL.
 	 * 
 	 * @param url
 	 *          the document source.
 	 * @return the node of document.
 	 * @throws IOException
 	 *           error while opening the stream.
 	 * @throws SAXException
 	 *           error while parsing.
 	 */
 	public synchronized Node parse(String url) throws IOException, SAXException {
 		return parse(new InputSource(url));
 	}
 
 	/***
 	 * Parse InputStream.
 	 * 
 	 * @param in
 	 *          the document source.
 	 * @return the node of document.
 	 * @throws IOException
 	 *           error while opening the stream.
 	 * @throws SAXException
 	 *           error while parsing.
 	 */
 	public synchronized Node parse(InputStream in) throws IOException,
 			SAXException {
 		Handler handler = new Handler();
 		XMLReader reader = parser.getXMLReader();
 		reader.setContentHandler(handler);
 		reader.setErrorHandler(handler);
 		reader.setEntityResolver(handler);
 		parser.parse(new InputSource(in), handler);
 		if (handler.error != null) {
 			throw handler.error;
 		}
 		Node doc = (Node) handler.top.get(0);
 		handler.clear();
 		return doc;
 	}
 
 	/***
 	 * The Default handler
 	 * 
 	 * @author <a href="mailto:fabdouglas@users.sourceforge.net">Fabrice Daugan
 	 *         </a>
 	 */
 	class Handler extends DefaultHandler {
 
 		Node top = new Node(null, null, null);
 
 		SAXParseException error;
 
 		@Override
 		public InputSource resolveEntity(String publicId, String systemId) {
 			if (systemId.endsWith(".xsd")) {
 				String xsdFile;
 				try {
 					xsdFile = IdConst.TBS_DIR + "/"
 							+ new File(new URI(systemId)).getName();
 				} catch (URISyntaxException e) {
 					return null;
 				}
 				return new InputSource(xsdFile);
 			}
 			return null;
 		}
 
 		private Node context = top;
 
 		void clear() {
 			top = null;
 			error = null;
 			context = null;
 		}
 
 		@Override
 		public void startElement(String uri, String localName, String qName,
 				Attributes attrs) throws SAXException {
 			String name = uri == null || uri.length() == 0 ? qName : localName;
 			Node node = new Node(context, name, attrs);
 			context.add(node);
 			context = node;
 			ContentHandler observer = null;
 			if (observerMap != null) {
 				observer = observerMap.get(name);
 			}
 			observers.push(observer);
 			for (ContentHandler handler : observers) {
 				if (handler != null) {
 					handler.startElement(uri, localName, qName, attrs);
 				}
 			}
 		}
 
 		@Override
 		public void notationDecl(String name, String publicId, String systemId) {
 			System.out.println("name:" + name + ",publicId:" + publicId
 					+ ",systemId:" + systemId);
 		}
 
 		@Override
 		public void endElement(String uri, String localName, String qName)
 				throws SAXException {
 			context = context.aParent;
 			for (ContentHandler handler : observers) {
 				if (handler != null) {
 					handler.endElement(uri, localName, qName);
 				}
 			}
 			observers.pop();
 		}
 
 		@Override
 		public void ignorableWhitespace(char[] buf, int offset, int len)
 				throws SAXException {
 			for (ContentHandler handler : observers) {
 				if (handler != null) {
 					handler.ignorableWhitespace(buf, offset, len);
 				}
 			}
 		}
 
 		@Override
 		public void characters(char[] buf, int offset, int len) throws SAXException {
 			context.add(new String(buf, offset, len));
 			for (int i = 0; i < observers.size(); i++) {
 				if (observers.get(i) != null) {
 					observers.get(i).characters(buf, offset, len);
 				}
 			}
 		}
 
 		@Override
 		public void warning(SAXParseException ex) {
 			ex.printStackTrace();
 			System.out.println("WARNING@" + getLocationString(ex) + " : "
 					+ ex.toString());
 		}
 
 		@Override
 		public void error(SAXParseException ex) {
 			// Save error and continue to report other errors
 			if (error == null) {
 				error = ex;
 			}
 			System.out.println("ERROR@" + getLocationString(ex) + " : "
 					+ ex.getMessage());
 		}
 
 		@Override
 		public void fatalError(SAXParseException ex) throws SAXException {
 			error = ex;
 			System.out.println("FATAL@" + getLocationString(ex) + " : "
 					+ ex.toString());
 			throw ex;
 		}
 
 		private String getLocationString(SAXParseException ex) {
 			return "line:" + ex.getLineNumber() + " col:" + ex.getColumnNumber();
 		}
 
 	}
 
 	/***
 	 * XML Attribute.
 	 */
 	public static class Attribute {
 
 		private String aName;
 
 		private String aValue;
 
 		/***
 		 * Create a new instance of this class.
 		 * 
 		 * @param n
 		 *          attribute name
 		 * @param v
 		 *          attribute value
 		 */
 		public Attribute(String n, String v) {
 			aName = n;
 			aValue = v;
 		}
 
 		/***
 		 * @return name
 		 */
 		public String getName() {
 			return aName;
 		}
 
 		/***
 		 * Set the attribute value.
 		 * 
 		 * @param value
 		 *          the attrivute value.
 		 */
 		public void setValue(String value) {
 			this.aValue = value;
 		}
 
 		/***
 		 * @return value
 		 */
 		public String getValue() {
 			return aValue;
 		}
 	}
 
 	/* ------------------------------------------------------------ */
 	/* ------------------------------------------------------------ */
 	/***
 	 * XML Node. Represents an XML element with optional attributes and ordered
 	 * content.
 	 */
 	public static class Node extends AbstractList<Object> {
 
 		Node aParent;
 
 		/***
 		 * Nodes
 		 */
 		public List<Object> aList;
 
 		/***
 		 * Tag name.
 		 */
 		public String aTag;
 
 		/***
 		 * Attributes
 		 */
 		public Attribute[] aAttrs;
 
 		/***
 		 * Is the last object is a string.
 		 */
 		public boolean aLastString = false;
 
 		/***
 		 * Create a new instance of this class.
 		 * 
 		 * @param parent
 		 *          parent node.
 		 * @param tag
 		 *          tag name.
 		 * @param attrs
 		 *          attributes
 		 */
 		public Node(Node parent, String tag, Attributes attrs) {
 			aParent = parent;
 			aTag = tag;
 			if (attrs != null) {
 				aAttrs = new Attribute[attrs.getLength()];
 				for (int i = 0; i < attrs.getLength(); i++) {
 					String name = attrs.getQName(i);
 					if (name == null || name.length() == 0) {
 						name = attrs.getQName(i);
 					}
 					aAttrs[i] = new Attribute(name, attrs.getValue(i));
 				}
 			}
 		}
 
 		/***
 		 * @param attr
 		 *          attribute to add.
 		 */
 		public void addFirstAttribute(Attribute attr) {
 			Attribute[] attrs = new Attribute[this.aAttrs.length + 1];
 			System.arraycopy(this.aAttrs, 0, attrs, 1, this.aAttrs.length);
 			attrs[0] = attr;
 			this.aAttrs = attrs;
 		}
 
 		/***
 		 * @param attributeName
 		 *          the attribute to remove.
 		 */
 		public void removeAttribute(String attributeName) {
 			for (int i = 0; i < this.aAttrs.length; i++) {
 				if (this.aAttrs[i].getName().equals(attributeName)) {
 					final Attribute[] attrs = new Attribute[this.aAttrs.length - 1];
 					if (this.aAttrs.length == 1) {
 						this.aAttrs = attrs;
 					} else {
 						if (i == 0) {
 							System.arraycopy(this.aAttrs, 1, attrs, 0, attrs.length);
 						} else {
 							System.arraycopy(this.aAttrs, 0, attrs, 0, i);
 							if (i != attrs.length) {
 								System
 										.arraycopy(this.aAttrs, i + 1, attrs, i, attrs.length - i);
 							}
 						}
 						this.aAttrs = attrs;
 						return;
 					}
 				}
 			}
 		}
 
 		/***
 		 * @param attr
 		 *          attribute to add.
 		 */
 		public void addAttribute(Attribute attr) {
 			for (Attribute attribute : aAttrs) {
 				if (attr.getName().equals(attribute.getName())) {
 					attribute.setValue(attr.getValue());
 					return;
 				}
 			}
 			final Attribute[] aAttrs = new Attribute[this.aAttrs.length + 1];
 			System.arraycopy(this.aAttrs, 0, aAttrs, 0, this.aAttrs.length);
 			aAttrs[this.aAttrs.length] = attr;
 			this.aAttrs = aAttrs;
 		}
 
 		/***
 		 * @return parent
 		 */
 		public Node getParent() {
 			return aParent;
 		}
 
 		/***
 		 * @return tag
 		 */
 		public String getTag() {
 			return aTag;
 		}
 
 		/***
 		 * Get an element attribute.
 		 * 
 		 * @param name
 		 *          the attribute name.
 		 * @return attribute or null.
 		 */
 		public String getAttribute(String name) {
 			return getAttribute(name, null);
 		}
 
 		/***
 		 * Get an element attribute.
 		 * 
 		 * @param name
 		 *          the attribute name.
 		 * @param dft
 		 *          the default value.
 		 * @return attribute or null.
 		 */
 		public String getAttribute(String name, String dft) {
 			if (aAttrs == null || name == null) {
 				return dft;
 			}
 			for (Attribute attribute : aAttrs) {
 				if (name.equals(attribute.getName())) {
 					return attribute.getValue();
 				}
 			}
 			return dft;
 		}
 
 		/***
 		 * Get the number of children nodes.
 		 * 
 		 * @return size
 		 */
 		@Override
 		public int size() {
 			if (aList != null) {
 				return aList.size();
 			}
 			return 0;
 		}
 
 		/***
 		 * Get the number of non text children nodes.
 		 * 
 		 * @return the number of non text children nodes.
 		 */
 		public int getNbNodes() {
 			if (aList == null)
 				return 0;
 			int count = 0;
 			for (Object obj : aList) {
 				if (obj instanceof Node) {
 					count++;
 				}
 			}
 			return count;
 		}
 
 		/***
 		 * Get the ith child node or content.
 		 * 
 		 * @param i
 		 *          index of node.
 		 * @return Node or String.
 		 */
 		@Override
 		public Object get(int i) {
 			if (aList != null) {
 				return aList.get(i);
 			}
 			return null;
 		}
 
 		/***
 		 * Get the first child node with the tag.
 		 * 
 		 * @param tag
 		 *          the tag name of node.
 		 * @return Node or null.
 		 */
 		public Node get(String tag) {
 			if (aList != null) {
 				for (Object o : aList) {
 					if (o instanceof Node) {
 						Node n = (Node) o;
 						if (tag.equals(n.aTag)) {
 							return n;
 						}
 					}
 				}
 			}
 			return null;
 		}
 
 		/***
 		 * Get the child nodes with the tag.
 		 * 
 		 * @param tag
 		 *          the tag name of node.
 		 * @return list of nodes or null.
 		 */
 		public List<Node> getNodes(String tag) {
 			final List<Node> list = new ArrayList<Node>();
 			if (aList != null) {
 				for (Object o : aList) {
 					if (o instanceof Node) {
 						Node n = (Node) o;
 						if (tag.equals(n.aTag)) {
 							list.add(n);
 						}
 					}
 				}
 			}
 			return list;
 		}
 
 		@Override
 		public void add(int i, Object o) {
 			if (aList == null) {
 				aList = new ArrayList<Object>();
 			}
 			if (o instanceof String) {
 				if (aLastString) {
 					int last = aList.size() - 1;
 					aList.set(last, (String) aList.get(last) + o);
 				} else {
 					aList.add(i, o);
 				}
 				aLastString = true;
 			} else {
 				aLastString = false;
 				aList.add(i, o);
 			}
 		}
 
 		/***
 		 * Inserts the specified element at the specified position in this list
 		 * (optional operation). Shifts the element currently at that position (if
 		 * any) and any subsequent elements to the right (adds one to their
 		 * indices).
 		 * <p>
 		 * This implementation always throws an UnsupportedOperationException.
 		 * 
 		 * @param o
 		 *          element to be inserted.
 		 */
 		public void removeElement(XmlParser.Node o) {
 			aLastString = false;
 			aList.remove(o);
 		}
 
 		/***
 		 * Removes the element at the specified position in this list (optional
 		 * operation). Shifts any subsequent elements to the left (subtracts one
 		 * from their indices). Returns the element that was removed from the list.
 		 * 
 		 * @param index
 		 *          the index of the element to removed.
 		 */
 		public void removeElement(int index) {
 			aLastString = false;
 			aList.remove(index);
 		}
 
 		/***
 		 * Replaces the element at the specified position in this list with the
 		 * specified element (optional operation).
 		 * 
 		 * @param index
 		 *          index of element to replace.
 		 * @param element
 		 *          element to be stored at the specified position.
 		 */
 		public void setElement(int index, Object element) {
 			aList.set(index, element);
 		}
 
 		@Override
 		public void clear() {
 			if (aList != null) {
 				aList.clear();
 			}
 			aList = null;
 		}
 
 		/***
 		 * Print this node using the specified printer.
 		 * 
 		 * @param printer
 		 *          used printer to add this node.
 		 */
 		public synchronized void print(PrintWriter printer) {
 			for (Attribute attribute : aAttrs) {
 				if ("xsi:schemaLocation".equals(attribute.getName())) {
 					XmlParser.Attribute[] attributes = new XmlParser.Attribute[aAttrs.length + 2];
 					System.arraycopy(aAttrs, 0, attributes, 2, aAttrs.length);
 					attributes[0] = new XmlParser.Attribute("xmlns:xsi", W3C_XML_SCHEMA
 							+ "-instance");
 					attributes[1] = new XmlParser.Attribute("xmlns", attribute.getValue()
 							.split(" ")[0]);
 					aAttrs = attributes;
 					break;
 				}
 			}
 			print(printer, "");
 		}
 
 		@Override
 		public synchronized String toString() {
 			return toString("");
 		}
 
 		@Override
 		public boolean equals(Object obj) {
 			return super.equals(obj);
 		}
 
 		@Override
 		public int hashCode() {
 			return aTag.hashCode();
 		}
 
 		/***
 		 * Convert to a string.
 		 * 
 		 * @param tag
 		 *          If false, only content is shown.
 		 * @return string
 		 */
 		private String toString(String ident) {
 			StringBuilder buf = new StringBuilder();
 			toString(buf, ident);
 			return buf.toString();
 		}
 
 		private void print(PrintWriter printer, String ident) {
 			printer.print(ident);
 			printer.print("<");
 			printer.print(aTag);
 			if (aAttrs != null) {
 				for (Attribute attribute : aAttrs) {
 					printer.print(' ');
 					printer.print(attribute.getName());
 					printer.print("=\"");
 					printer.print(normalize(attribute.getValue()));
 					printer.print("\"");
 				}
 			}
 			if (aList != null) {
 				printer.print(">");
 				printer.println();
 				for (Object o : aList) {
 					if (o == null) {
 						continue;
 					}
 					if (o instanceof Node) {
 						((Node) o).print(printer, ident + "\t");
 					} else {
 						printer.print(normalize(StringUtils.trimToEmpty(o.toString())));
 					}
 				}
 				printer.print(ident);
 				printer.print("</");
 				printer.print(aTag);
 				printer.print(">");
 			} else {
 				printer.print("/>");
 			}
 			printer.println();
 		}
 
 		private void toString(StringBuilder buf, String ident) {
 			buf.append(ident);
 			buf.append("<");
 			buf.append(aTag);
 			if (aAttrs != null) {
 				for (Attribute attribute : aAttrs) {
 					buf.append(' ');
 					buf.append(attribute.getName());
 					buf.append("=\"");
 					buf.append(normalize(attribute.getValue()));
 					buf.append("\"");
 				}
 			}
 			if (aList != null) {
 				buf.append(">\n");
 				for (Object o : aList) {
 					if (o == null) {
 						continue;
 					}
 					if (o instanceof Node) {
 						((Node) o).toString(buf, ident + "\t");
 					} else {
 						buf.append(normalize(StringUtils.trimToEmpty(o.toString())));
 					}
 				}
 				buf.append(ident);
 				buf.append("</");
 				buf.append(aTag);
 				buf.append(">\n");
 			} else {
 				buf.append("/>\n");
 			}
 		}
 	}
 
 	/***
 	 * Return the given text as XML string.
 	 * 
 	 * @param text
 	 *          the text containing non serializable tags.
 	 * @return the given text as XML string.
 	 */
 	public static String normalize(String text) {
 		return text.replace("&", "`").replace("&", "&amp;").replace("'", "&#39;")
 				.replace("<", "&lt;").replace(">", "&gt;").replace("\"", "&quot;");
 	}
 
 	/***
 	 * The SAX parser
 	 */
 	private SAXParser parser;
 
 	Map<String, ContentHandler> observerMap;
 
 	Stack<ContentHandler> observers = new Stack<ContentHandler>();
 
 	static final String JAXP_SCHEMA_SOURCE = "http://java.sun.com/xml/jaxp/properties/schemaSource";
 
 	static final String JAXP_SCHEMA_LANGUAGE = "http://java.sun.com/xml/jaxp/properties/schemaLanguage";
 
 	static final String W3C_XML_SCHEMA = "http://www.w3.org/2001/XMLSchema";
 
 	static final String MP_XML_SCHEMA = IdConst.TBS_DIR + "/" + IdConst.TBS_XSD;
 }