package net.sf.saxon.event;
import net.sf.saxon.om.AttributeCollectionImpl;
import net.sf.saxon.om.NamePool;
import net.sf.saxon.om.NamespaceConstant;
import net.sf.saxon.om.StandardNames;
import net.sf.saxon.trans.XPathException;
import net.sf.saxon.value.Whitespace;
import javax.xml.transform.OutputKeys;
import java.util.Properties;
/**
* The MetaTagAdjuster adds a meta element to the content of the head element, indicating
* the required content type and encoding; it also removes any existing meta element
* containing this information
*/
public class MetaTagAdjuster extends ProxyReceiver {
boolean seekingHead = true;
int droppingMetaTags = -1;
boolean inMetaTag = false;
boolean foundHead = false;
int metaCode;
short requiredURICode = 0;
AttributeCollectionImpl attributes;
String encoding;
String mediaType;
int level = 0;
boolean isXHTML = false;
/**
* Create a new MetaTagAdjuster
*/
public MetaTagAdjuster() {
}
/**
* Set output properties
*/
public void setOutputProperties(Properties details) {
encoding = details.getProperty(OutputKeys.ENCODING);
if (encoding == null) {
encoding = "UTF-8";
}
mediaType = details.getProperty(OutputKeys.MEDIA_TYPE);
if (mediaType == null) {
mediaType = "text/html";
}
}
/**
* Indicate whether we're handling HTML or XHTML
*/
public void setIsXHTML(boolean xhtml) {
isXHTML = xhtml;
if (xhtml) {
requiredURICode = getNamePool().getCodeForURI(NamespaceConstant.XHTML);
} else {
requiredURICode = 0;
}
}
/**
* Compare a name: case-blindly in the case of HTML, case-sensitive for XHTML
*/
private boolean comparesEqual(String name1, String name2) {
if (isXHTML) {
return name1.equals(name2);
} else {
return name1.equalsIgnoreCase(name2);
}
}
/**
* Notify the start of an element
*
* @param nameCode integer code identifying the name of the element within the name pool.
* @param typeCode integer code identifying the element's type within the name pool.
* @param properties properties of the element node
*/
public void startElement(int nameCode, int typeCode, int locationId, int properties) throws XPathException {
if (droppingMetaTags == level) {
metaCode = nameCode;
int uriCode = getNamePool().getURICode(nameCode);
String localName = getNamePool().getLocalName(nameCode);
if (uriCode == requiredURICode && comparesEqual(localName, "meta")) {
inMetaTag = true;
attributes.clear();
return;
}
}
level++;
nextReceiver.startElement(nameCode, typeCode, locationId, properties);
if (seekingHead) {
NamePool namePool = getNamePool();
int uriCode = namePool.getURICode(nameCode);
String localName = namePool.getLocalName(nameCode);
if (uriCode == requiredURICode && comparesEqual(localName, "head")) {
foundHead = true;
}
}
}
/**
* Notify an attribute. Attributes are notified after the startElement event, and before any
* children. Namespaces and attributes may be intermingled.
*
* @param nameCode The name of the attribute, as held in the name pool
* @param typeCode The type of the attribute, as held in the name pool
* @param properties Bit significant value. The following bits are defined:
* <dd>DISABLE_ESCAPING</dd> <dt>Disable escaping for this attribute</dt>
* <dd>NO_SPECIAL_CHARACTERS</dd> <dt>Attribute value contains no special characters</dt>
* @throws IllegalStateException: attempt to output an attribute when there is no open element
* start tag
*/
public void attribute(int nameCode, int typeCode, CharSequence value, int locationId, int properties) throws XPathException {
if (inMetaTag) {
attributes.addAttribute(nameCode, typeCode, value.toString(), locationId, properties);
} else {
nextReceiver.attribute(nameCode, typeCode, value, locationId, properties);
}
}
/**
* Notify the start of the content, that is, the completion of all attributes and namespaces.
* Note that the initial receiver of output from XSLT instructions will not receive this event,
* it has to detect it itself. Note that this event is reported for every element even if it has
* no attributes, no namespaces, and no content.
*/
public void startContent() throws XPathException {
if (foundHead) {
foundHead = false;
NamePool namePool = getNamePool();
nextReceiver.startContent();
int metaCode = namePool.allocate("", requiredURICode, "meta");
nextReceiver.startElement(metaCode, StandardNames.XS_UNTYPED, 0, 0);
int httpEquivCode = namePool.allocate("", "", "http-equiv");
nextReceiver.attribute(httpEquivCode, StandardNames.XS_UNTYPED_ATOMIC, "Content-Type", 0, 0);
int contentCode = namePool.allocate("", "", "content");
nextReceiver.attribute(contentCode, StandardNames.XS_UNTYPED_ATOMIC, mediaType + "; charset=" + encoding, 0, 0);
nextReceiver.startContent();
droppingMetaTags = level;
seekingHead = false;
attributes = new AttributeCollectionImpl(namePool);
nextReceiver.endElement();
}
if (!inMetaTag) {
nextReceiver.startContent();
}
}
/**
* End of element
*/
public void endElement() throws XPathException {
if (inMetaTag) {
inMetaTag = false;
// if there was an http-equiv="ContentType" attribute, discard the meta element entirely
boolean found = false;
for (int i=0; i<attributes.getLength(); i++) {
String name = attributes.getLocalName(i);
if (comparesEqual(name, "http-equiv")) {
String value = Whitespace.trim(attributes.getValue(i));
if (value.equalsIgnoreCase("Content-Type")) {
// case-blind comparison even for XHTML
found = true;
break;
}
}
}
if (!found) {
// this was a meta element, but not one of the kind that we discard
nextReceiver.startElement(metaCode, StandardNames.XS_UNTYPED, 0, 0);
for (int i=0; i<attributes.getLength(); i++) {
int nameCode = attributes.getNameCode(i);
int typeCode = attributes.getTypeAnnotation(i);
String value = attributes.getValue(i);
int locationId = attributes.getLocationId(i);
int properties = attributes.getProperties(i);
nextReceiver.attribute(nameCode, typeCode, value, locationId, properties);
}
nextReceiver.startContent();
nextReceiver.endElement();
}
} else {
level--;
if (droppingMetaTags == level+1) {
droppingMetaTags = -1;
}
nextReceiver.endElement();
}
}
}
//
// The contents of this file are subject to the Mozilla Public License Version 1.0 (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.mozilla.org/MPL/
//
// Software distributed under the License is distributed on an "AS IS" basis,
// WITHOUT WARRANTY OF ANY KIND, either express or implied.
// See the License for the specific language governing rights and limitations under the License.
//
// The Original Code is: all this file.
//
// The Initial Developer of the Original Code is Michael H. Kay.
//
// Portions created by (your name) are Copyright (C) (your legal entity). All Rights Reserved.
//
// Contributor(s): none.
//