/**
* ===========================================
* LibLayout : a free Java layouting library
* ===========================================
*
* Project Info: http://reporting.pentaho.org/liblayout/
*
* (C) Copyright 2006-2007, by Pentaho Corporation and Contributors.
*
* This library is free software; you can redistribute it and/or modify it under the terms
* of the GNU Lesser General Public License as published by the Free Software Foundation;
* either version 2.1 of the License, or (at your option) any later version.
*
* This library 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 Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public License along with this
* library; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330,
* Boston, MA 02111-1307, USA.
*
* [Java is a trademark or registered trademark of Sun Microsystems, Inc.
* in the United States and other countries.]
*
* ------------
* $Id: XAlternateTextResolveHandler.java,v 1.6 2007/04/02 11:41:14 taqua Exp $
* ------------
* (C) Copyright 2006-2007, by Pentaho Corporation.
*/
package org.jfree.layouting.layouter.style.resolver.computed.content;
import java.util.ArrayList;
import java.net.URL;
import org.jfree.layouting.DocumentContextUtility;
import org.jfree.layouting.LayoutProcess;
import org.jfree.layouting.input.style.StyleKey;
import org.jfree.layouting.input.style.keys.content.ContentStyleKeys;
import org.jfree.layouting.input.style.keys.content.ContentValues;
import org.jfree.layouting.input.style.values.CSSAttrFunction;
import org.jfree.layouting.input.style.values.CSSConstant;
import org.jfree.layouting.input.style.values.CSSFunctionValue;
import org.jfree.layouting.input.style.values.CSSStringType;
import org.jfree.layouting.input.style.values.CSSStringValue;
import org.jfree.layouting.input.style.values.CSSValue;
import org.jfree.layouting.input.style.values.CSSValueList;
import org.jfree.layouting.layouter.content.ContentToken;
import org.jfree.layouting.layouter.content.statics.ExternalContentToken;
import org.jfree.layouting.layouter.content.statics.ResourceContentToken;
import org.jfree.layouting.layouter.content.statics.StaticTextToken;
import org.jfree.layouting.layouter.context.ContentSpecification;
import org.jfree.layouting.layouter.context.LayoutContext;
import org.jfree.layouting.layouter.model.LayoutElement;
import org.jfree.layouting.layouter.style.functions.FunctionEvaluationException;
import org.jfree.layouting.layouter.style.functions.FunctionFactory;
import org.jfree.layouting.layouter.style.functions.values.StyleValueFunction;
import org.jfree.layouting.layouter.style.resolver.ResolveHandler;
import org.jfree.layouting.layouter.style.values.CSSRawValue;
import org.jfree.layouting.layouter.style.values.CSSResourceValue;
import org.jfree.resourceloader.ResourceKey;
import org.jfree.resourceloader.ResourceManager;
import org.jfree.util.Log;
public class XAlternateTextResolveHandler implements ResolveHandler
{
private static final ContentToken[] DEFAULT_CONTENT = new ContentToken[0];
public XAlternateTextResolveHandler ()
{
}
/**
* This indirectly defines the resolve order. The higher the order, the more dependent
* is the resolver on other resolvers to be complete.
*
* @return the array of required style keys.
*/
public StyleKey[] getRequiredStyles ()
{
return new StyleKey[] {
ContentStyleKeys.COUNTER_RESET,
ContentStyleKeys.COUNTER_INCREMENT,
ContentStyleKeys.QUOTES,
ContentStyleKeys.STRING_DEFINE
};
}
/**
* Resolves a String. As the string may contain the 'contents' property, it
* is not resolvable here. The ContentNormalizer needs to handle this property
* instead. (But this code prepares everything ..)
*
* @param currentNode
* @param style
*/
public void resolve (final LayoutProcess process,
final LayoutElement element,
final StyleKey key)
{
final LayoutContext layoutContext = element.getLayoutContext();
final ContentSpecification contentSpecification =
layoutContext.getContentSpecification();
final CSSValue value = layoutContext.getValue(key);
if (value instanceof CSSConstant)
{
if (ContentValues.NONE.equals(value))
{
contentSpecification.setStrings(XAlternateTextResolveHandler.DEFAULT_CONTENT);
return;
}
}
contentSpecification.setStrings(XAlternateTextResolveHandler.DEFAULT_CONTENT);
if (value instanceof CSSAttrFunction)
{
final ContentToken token =
evaluateFunction((CSSFunctionValue) value, process, element);
if (token == null)
{
return;
}
contentSpecification.setStrings(new ContentToken[]{token});
}
if (value instanceof CSSValueList == false)
{
return; // cant handle that one
}
final ArrayList tokens = new ArrayList();
final CSSValueList list = (CSSValueList) value;
final int size = list.getLength();
for (int i = 0; i < size; i++)
{
final CSSValueList sequence = (CSSValueList) list.getItem(i);
for (int j = 0; j < sequence.getLength(); j++)
{
final CSSValue content = sequence.getItem(j);
final ContentToken token = createToken(process, element, content);
if (token == null)
{
// ok, a failure. Skip to the next content spec ...
tokens.clear();
break;
}
tokens.add(token);
}
}
final ContentToken[] contents = (ContentToken[]) tokens.toArray
(new ContentToken[tokens.size()]);
contentSpecification.setStrings(contents);
}
private ContentToken createToken (LayoutProcess process,
LayoutElement element,
CSSValue content)
{
if (content instanceof CSSStringValue)
{
CSSStringValue sval = (CSSStringValue) content;
if (CSSStringType.STRING.equals(sval.getType()))
{
return new StaticTextToken(sval.getValue());
}
else
{
// this is an external URL, so try to load it.
CSSFunctionValue function = new CSSFunctionValue
("url", new CSSValue[]{sval});
return evaluateFunction(function, process, element);
}
}
if (content instanceof CSSFunctionValue)
{
return evaluateFunction((CSSFunctionValue) content, process, element);
}
if (content instanceof CSSConstant)
{
if (ContentValues.DOCUMENT_URL.equals(content))
{
Object docUrl = process.getDocumentContext().getMetaAttribute
("document-url");
if (docUrl != null)
{
return new StaticTextToken(String.valueOf(docUrl));
}
final ResourceKey baseKey =
DocumentContextUtility.getBaseResource(process.getDocumentContext());
final ResourceManager resourceManager =
DocumentContextUtility.getResourceManager(process.getDocumentContext());
final URL url = resourceManager.toURL(baseKey);
if (url != null)
{
return new StaticTextToken(url.toExternalForm());
}
return null;
}
}
return null;
}
private ContentToken evaluateFunction(final CSSFunctionValue function,
final LayoutProcess process,
final LayoutElement element)
{
StyleValueFunction styleFunction =
FunctionFactory.getInstance().getStyleFunction(function.getFunctionName());
try
{
CSSValue value = styleFunction.evaluate(process, element, function);
if (value instanceof CSSResourceValue)
{
CSSResourceValue refValue = (CSSResourceValue) value;
return new ResourceContentToken(refValue.getValue());
}
else if (value instanceof CSSStringValue)
{
CSSStringValue strval = (CSSStringValue) value;
return new StaticTextToken(strval.getValue());
}
else if (value instanceof CSSRawValue)
{
CSSRawValue rawValue = (CSSRawValue) value;
return new ExternalContentToken(rawValue.getValue());
}
return new StaticTextToken(value.getCSSText());
}
catch (FunctionEvaluationException e)
{
Log.debug ("Evaluation failed " + e);
return null;
}
}
}