/bundles/plugins-trunk/XML/xml/hyperlinks/HTMLHyperlinkSource.java

/*

 * HTMLHyperlinkSource.java - Hyperlink source from the XML plugin

 * :tabSize=8:indentSize=8:noTabs=false:

 * :folding=explicit:collapseFolds=1:

 *

 * Copyright (C) 2011 Eric Le Lay

 *

 * 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 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 xml.hyperlinks;



import java.net.URI;

import java.util.regex.Pattern;

import java.util.regex.Matcher;

import java.util.Map;

import java.util.HashMap;

import java.util.Set;

import java.util.HashSet;

import java.util.Iterator;

import java.util.Arrays;

import javax.swing.tree.DefaultMutableTreeNode;



import org.gjt.sp.jedit.View;

import org.gjt.sp.jedit.jEdit;

import org.gjt.sp.jedit.Buffer;

import org.gjt.sp.util.Log;



import sidekick.SideKickParsedData;

import sidekick.IAsset;

import sidekick.util.ElementUtil;

import sidekick.util.Location;

import sidekick.util.SideKickAsset;

import sidekick.util.SideKickElement;



import gatchan.jedit.hyperlinks.*;



import static xml.Debug.*;

import xml.Resolver;

import xml.XmlParsedData;

import sidekick.html.parser.html.*;

import static sidekick.html.parser.html.HtmlDocument.*;

import xml.completion.ElementDecl;

import xml.completion.IDDecl;



/**

 * Provides hyperlinks from HTML attributes.

 * Supported hyperlinks are all attributes with type URI

 * in the HTML 4.01 spec.

 * Links to other documents and anchors inside document

 * are supported, but fragment identifiers in other documents

 * are not.

 * the HTML/HEAD/BASE element is used to resolve URIs

 * if present.

 * No reparsing is required, contrary to XMLHyperlinkSource

 * which reparses the start tag.

 *

 * @author Eric Le Lay

 * @version $Id: HTMLHyperlinkSource.java 21198 2012-02-24 11:19:21Z kerik-sf $

 */

public class HTMLHyperlinkSource implements HyperlinkSource

{

	/**

	 * Returns the hyperlink for the given offset.

	 * returns an hyperlink as soon as pointer enters the attribute's value

	 *

	 * @param buffer the buffer

	 * @param offset the offset

	 * @return the hyperlink (or null if there is no hyperlink)

	 */

	public Hyperlink getHyperlink(Buffer buffer, int offset){

		View view = jEdit.getActiveView();

		XmlParsedData data = XmlParsedData.getParsedData(view, false);

		if(data==null)return null;

		

		IAsset asset = data.getAssetAtOffset(offset);

		if(asset == null){

			Log.log(Log.DEBUG, HTMLHyperlinkSource.class,"no Sidekick asset here");

			return null;

		} else {

			int wantedLine = buffer.getLineOfOffset(offset);

			int wantedLineOffset = buffer.getVirtualWidth(wantedLine, offset - buffer.getLineStartOffset(wantedLine));



			SideKickElement elt = ((SideKickAsset)asset).getElement();

			

			Tag startTag;

			if(elt instanceof TagBlock){

				startTag = ((TagBlock)elt).startTag;

			}else if(elt instanceof Tag){

				startTag = (Tag)elt;

			}else{

				Log.log(Log.WARNING,HTMLHyperlinkSource.class,"unexpected asset type: "+elt.getClass()+", please report");

				startTag = null;

				return null;

			}



			int start = ElementUtil.createStartPosition(buffer,startTag).getOffset();

			int end= ElementUtil.createEndPosition(buffer,startTag).getOffset();

			/* if the offset is inside start tag */

			if(offset <= end)

			{

				AttributeList al = startTag.attributeList;

				if(al == null){

					if(DEBUG_HYPERLINKS)Log.log(Log.DEBUG,HTMLHyperlinkSource.class,"no attribute in this element");

					return null;

				}else{

					for(Attribute att: al.attributes){

						// offset is inside attribute's value

						if(  (    att.getValueStartLocation().line < wantedLine+1

						       || (att.getValueStartLocation().line == wantedLine+1

							   && att.getValueStartLocation().column <= wantedLineOffset)

						      )

						      &&

						      (    att.getEndLocation().line > wantedLine+1

						       || (att.getEndLocation().line == wantedLine+1

							   && att.getEndLocation().column > wantedLineOffset)

						      )

						  )

						{

							return getHyperlinkForAttribute(buffer, offset, data, startTag, att);

						}

					}

					if(DEBUG_HYPERLINKS)Log.log(Log.DEBUG,HTMLHyperlinkSource.class,"not inside attributes");

					return null;

				}

			}else{

				return null;

			}

		}

	}

	

	/**

	 * get an hyperlink for an identified HTML attribute

	 * @param	buffer	current buffer

	 * @param	offset	offset where an hyperlink is required in current buffer

	 * @param	data		sidekick tree for current buffer

	 * @param	asset		element containing offset

	 * @param	att		parsed attribute

	 */

	public Hyperlink getHyperlinkForAttribute(

		Buffer buffer, int offset, XmlParsedData data, 

		Tag startTag, Attribute att)

	{

		String tagLocalName = startTag.tagName;

		

		String localName = att.getName();

		String value = att.getValue();

		boolean quoted;

		if((value.startsWith("\"")&&value.endsWith("\""))

			||(value.startsWith("'")&&value.endsWith("'")))

		{

			value = value.substring(1,value.length()-1);

			quoted = true;

		}else{

			quoted = false;

		}

		

		

		Hyperlink h = getHyperlinkForAttribute(buffer, offset,

			tagLocalName, localName, value,

			data, startTag, att, quoted);

		

		if(h == null) {

		

			ElementDecl eltDecl  = data.getElementDecl(localName,offset);

			if(eltDecl == null){

				if(DEBUG_HYPERLINKS)Log.log(Log.DEBUG,HTMLHyperlinkSource.class,"no element declaration for "+tagLocalName);

			}else{

				ElementDecl.AttributeDecl attDecl = eltDecl.attributeHash.get(localName);

				if(attDecl == null){

					if(DEBUG_HYPERLINKS)Log.log(Log.DEBUG,HTMLHyperlinkSource.class,"no attribute declaration for "+localName);

					return null;

				}else{

					if("IDREF".equals(attDecl.type)){

						return getHyperlinkForIDREF(buffer, data, value, att, quoted);

					}else if("anyURI".equals(attDecl.type)){

						String href =  resolve(value, buffer, offset, data);

						if(href!=null){

							return newJEditOpenFileHyperlink(buffer, att, href, quoted);

						}

					}else if("IDREFS".equals(attDecl.type)){

						return getHyperlinkForIDREFS(buffer, offset, data, value, att, quoted);

					}

					return null;

				}

			}

			

		} else {

			return h;

		}

		return null;

	}

	

	/**

	 * creates an hyperlink to the location of the element with id (in same or another buffer).

	 * @param	buffer	current buffer

	 * @param	data		sidekick tree

	 * @param	id		id we are looking for

	 * @param	att		parsed attribute (for hyperlink boundaries)

	 * @param	quoted	is the value inside quotes ?

	 */

	public Hyperlink getHyperlinkForIDREF(Buffer buffer,

		XmlParsedData data, String id, Attribute att,

		boolean quoted)

	{

		IDDecl idDecl = data.getIDDecl(id);

		if(idDecl == null){

			return null;

		} else{

			return newJEditOpenFileAndGotoHyperlink(buffer, att,

			idDecl.uri, idDecl.line, idDecl.column, quoted);

		}

	}

	

	// {{{ getHyperlinkForIDREFS() method

	private static final Pattern noWSPattern = Pattern.compile("[^\\s]+");

	/**

	 * creates an hyperlink to the location of the element with id (in same or another buffer)

	 * @param	buffer	current buffer

	 * @param	offset	offset of required hyperlink

	 * @param	data		sidekick tree

	 * @param	attValue		ids in the attribute

	 * @param	att		parsed attribute (for hyperlink boundaries)

	 * @param	quoted	is the value inside quotes ?

	 */

	public Hyperlink getHyperlinkForIDREFS(Buffer buffer, int offset,

		XmlParsedData data, String attValue, Attribute att,

		boolean quoted)

	{

		int attStart = xml.ElementUtil.createOffset(buffer, att.getValueStartLocation());

		// +1 for the quote around the attribute value

		if(quoted)attStart++;

		

		Matcher m = noWSPattern.matcher(attValue);

		while(m.find()){

			int st = m.start(0);

			int nd = m.end(0);

			if(attStart + st <= offset && attStart + nd >= offset){

				IDDecl idDecl = data.getIDDecl(m.group(0));

				if(idDecl==null)return null;

				int start = attStart + st;

				int end= attStart + nd;

				int line = buffer.getLineOfOffset(start);

				return new jEditOpenFileAndGotoHyperlink(start, end, line, idDecl.uri, idDecl.line, idDecl.column);

			}

		}

		return null;

	}//}}}

	

	//{{{ getHyperlinkForAttribute(tagName,attName) method

	private static final Map<String,Set<String>> uriAttributes = new HashMap<String,Set<String>>();

	static{

		HashSet<String> h;

		

		h = new HashSet<String>();

		h.add("href");

		uriAttributes.put("a", h);

		uriAttributes.put("area", h);

		uriAttributes.put("link", h);

		

		h = new HashSet<String>();

		h.add("longdesc");

		h.add("usemap");

		uriAttributes.put("img", h);

		

		h = new HashSet<String>();

		h.add("cite");

		uriAttributes.put("q", h);

		uriAttributes.put("blockquote", h);

		uriAttributes.put("ins", h);

		uriAttributes.put("del", h);

		

		h = new HashSet<String>();

		h.add("usemap");

		uriAttributes.put("input", h);

		uriAttributes.put("object", h);

		

		h = new HashSet<String>();

		h.add("src");

		uriAttributes.put("script", h);

	}

	

	/**

	 * recognize hyperlink attributes by their parent element's

	 * namespace:localname and/or their namespace:localname

	 */

	public Hyperlink getHyperlinkForAttribute(Buffer buffer, int offset,

		String tagLocalName,

		String attLocalName, String attValue,

		XmlParsedData data, Tag tag, Attribute att,

		boolean quoted)

	{

		boolean isHREF = false;

		

		if(uriAttributes.containsKey(tagLocalName)

			&& uriAttributes.get(tagLocalName).contains(attLocalName))

		{

			if(attValue.startsWith("#")){

				Location found = getNamedAnchorLocation(data, attValue.substring(1));

				if(found != null){

					// OpenFileAndGoto expects real line&column,

					// not virtual column

					int toffset = xml.ElementUtil.createOffset(buffer, found);

					int line = buffer.getLineOfOffset(toffset);

					int column = toffset - buffer.getLineStartOffset(line);

					// it's OK to have a path

					String href = buffer.getPath();

					return newJEditOpenFileAndGotoHyperlink(

						buffer, att, href, line, column, quoted);

				}

			}else{

				String href = resolve(attValue, buffer, offset, data);

				if(href==null){

					return null;

				}else{

					return newJEditOpenFileHyperlink(

						buffer, att, href, quoted);

				}

			}

		} else if("object".equals(tagLocalName)

			&& ("classid".equals(attLocalName)

				|| "data".equals(attLocalName)))

		{

			/* must resolve against codebase if present */

			String href = resolveRelativeTo(attValue,

				tag.getAttributeValue("codebase"));



			href = resolve(href, buffer, offset, data);

			if(href==null){

				return null;

			}else{

				return newJEditOpenFileHyperlink(

					buffer, att, href, quoted);

			}

		} else if("object".equals(tagLocalName)

			&& "archive".equals(attLocalName))

		{

			// +1 for the quote around the attribute value

			int attStart = xml.ElementUtil.createOffset(buffer, att.getValueStartLocation()) +1;

			

			Matcher m = noWSPattern.matcher(attValue);

			while(m.find()){

				int st = m.start(0);

				int nd = m.end(0);

				if(attStart + st <= offset && attStart + nd >= offset){

					/* must resolve against codebase if present */

					String href = resolveRelativeTo(m.group(0),

						tag.getAttributeValue("codebase"));



					href = resolve(href, buffer, offset, data);

					if(href==null)href=m.group(0);

					int start = attStart + st;

					int end= attStart + nd;

					int line = buffer.getLineOfOffset(start);

					return new jEditOpenFileHyperlink(start, end, line, href);

				}

			}

		}

		return null;

	}//}}}

	

	//{{{ resolveRelativeTo(href,base) methode

	/**

	 * resolves using URI.resolve() href against base

	*/	

	String resolveRelativeTo(String href, String base){

		if(base == null || "".equals(base))return href;

		

		try{

			return URI.create(base).resolve(href).toString();

		}catch(IllegalArgumentException iae){

			Log.log(Log.WARNING,HTMLHyperlinkSource.class,"error resolving against codebase",iae);

			return href;

		}

	}//}}}

	

	//{{{ resolve(uri, buffer) method

	/**

	 * resolve a potentially relative uri using HTML BASE element,

	 * the buffer's URL, xml.Resolver.

	 * Has the effect of opening the cached document if it's in cache (eg. docbook XSD if not in catalog).

	 * Maybe this is not desirable, because if there is a relative link in this document, it won't work

	 * because the document will be .jedit/dtds/cachexxxxx.xml and not the real url.

	 *

	 * @param	uri		text of uri to reach

	 * @param	buffer	current buffer

	 * @param	offset	offset in current buffer where an hyperlink is required

	 * @param	data		SideKick parsed data

	 *

	 * @return	resolved URL

	 */

	public String resolve(String uri, Buffer buffer, int offset, XmlParsedData data)

	{

		String href = null;

		String base = xml.PathUtilities.pathToURL(buffer.getPath());

		

		// {{{ use html/head/base

		TagBlock html = getHTML(data);

		if(html != null

			&& html.body.size()>0)

		{

			for(Iterator ith =  ((TagBlock)html).body.iterator();ith.hasNext();){

				HtmlElement head = (HtmlElement) ith.next();

				if(head instanceof TagBlock){

					if("head".equalsIgnoreCase(((TagBlock)head).startTag.tagName))

					{

						for(Iterator it =  ((TagBlock)head).body.iterator();it.hasNext();){

							HtmlElement e = (HtmlElement)it.next();

							if(e instanceof Tag

								&& "base".equalsIgnoreCase(((Tag)e).tagName))

							{

								// Base must be absolute in HTML 4.01

								String preBase = ((Tag)e).getAttributeValue("href");

								try{

									// add a dummy component, otherwise xml.Resolver

									// removes the last part of the xml:base

									// FIXME: review xml.Resolver : it should only be used with URLs

									// for current, now, so could use URI.resolve() instead of removing

									// last part of the path to get the parent...

									base = URI.create(preBase).resolve("dummy").toString();

								}catch(IllegalArgumentException iae){

									Log.log(Log.WARNING, XMLHyperlinkSource.class, "error resolving uri", iae);

								}

								break;

							}

						}

					}

					break;

				}

			}

		}//}}}

		

		try{

			href = Resolver.instance().resolveEntityToPath(

				"", /*name*/

				"", /*publicId*/

				base, /*current, augmented by xml:base */

				uri);

		}catch(java.io.IOException ioe){

			Log.log(Log.ERROR,XMLHyperlinkSource.class,"error resolving href="+uri,ioe);

		}

		return href;

	}//}}}

	

	/**

	 * create an hyperlink for attribute att.

	 * the hyperlink will span whole attribute value

	 * @param	buffer	current buffer

	 * @param	att		parsed attribute

	 * @param	href		uri to open

	 * @param	quoted	is the value inside quotes ?

	 */

	public Hyperlink newJEditOpenFileHyperlink(

		Buffer buffer, Attribute att, String href,

		boolean quoted)

	{

		int start = xml.ElementUtil.createOffset(buffer,att.getValueStartLocation());

		int end= xml.ElementUtil.createOffset(buffer,att.getEndLocation());

		if(quoted){

			start++;

			end--;

		}

        	int line = buffer.getLineOfOffset(start);

        	return new jEditOpenFileHyperlink(start, end, line, href);

	}



	/**

	 * create an hyperlink for attribute att.

	 * the hyperlink will span whole attribute value

	 * @param	buffer	current buffer

	 * @param	att		parsed attribute

	 * @param	href		uri to open

	 * @param	gotoLine	target line in buffer

	 * @param	gotoCol	target column in buffer

	 * @param	quoted	is the value inside quotes ?

	 */

	public Hyperlink newJEditOpenFileAndGotoHyperlink(

		Buffer buffer, Attribute att, String href, int gotoLine, int gotoCol,

		boolean quoted)

	{

		int start = xml.ElementUtil.createOffset(buffer,att.getValueStartLocation());

		int end= xml.ElementUtil.createOffset(buffer,att.getEndLocation());

		if(quoted){

			start++;

			end--;

		}

        	int line = buffer.getLineOfOffset(start);

        	return new jEditOpenFileAndGotoHyperlink(start, end, line, href, gotoLine, gotoCol);

	}



	TagBlock getHTML(XmlParsedData data) {

		DefaultMutableTreeNode tn = (DefaultMutableTreeNode)data.root;

		

		DefaultMutableTreeNode docRoot = (DefaultMutableTreeNode)tn.getFirstChild();

		

		if(docRoot == null){

			if(DEBUG_HYPERLINKS)Log.log(Log.WARNING,HTMLHyperlinkSource.class,"not parsed ??");

			return null;

		}else{

			SideKickElement elt = ((SideKickAsset)data.getAsset(docRoot)).getElement();

			if(elt instanceof TagBlock){

				return (TagBlock)elt;

			}

		}

		return null;

	}

	

	private static class FoundException extends RuntimeException{}

	private static final FoundException foundException = new FoundException();

	

	private static final class NamedAnchorVisitor extends HtmlVisitor{

		private final String searchedAnchor;

		Location foundLoc;

		

		NamedAnchorVisitor(String searched){

			searchedAnchor = searched;

			foundLoc = null;

		}

		

		public void visit(Tag t) {

			String v = null;

			if("a".equalsIgnoreCase(t.tagName)){

				 v = t.getAttributeValue("name");

			}

			if(v == null){

				v = t.getAttributeValue("id");

			}

			if(searchedAnchor.equals(v)){

				foundLoc = t.getStartLocation();

				throw foundException;

			}

		}

	}

	

	public Location getNamedAnchorLocation(XmlParsedData data, String name){

		TagBlock html = getHTML(data);

		if(html != null){

			NamedAnchorVisitor v = new NamedAnchorVisitor(name);

			try{

				html.accept(v);

			}catch(FoundException e){

				return v.foundLoc;

			}

		}

		return null;

	}



	public static HyperlinkSource create(){

		return new FallbackHyperlinkSource(

			Arrays.asList(new HTMLHyperlinkSource(),

				new gatchan.jedit.hyperlinks.url.URLHyperlinkSource()));

	}

}