xml/impl/src/com/intellij/xml/util/documentation/HtmlDocumentationProvider.java - platform/tools/idea - Git at Google

 /*
  * Copyright 2000-2014 JetBrains s.r.o.
  *
  * 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 com.intellij.xml.util.documentation;

 import com.intellij.lang.Language;
 import com.intellij.lang.LanguageDocumentation;
 import com.intellij.lang.documentation.DocumentationProvider;
 import com.intellij.lang.documentation.DocumentationUtil;
 import com.intellij.openapi.util.text.StringUtil;
 import com.intellij.psi.PsiElement;
 import com.intellij.psi.PsiManager;
 import com.intellij.psi.PsiWhiteSpace;
 import com.intellij.psi.XmlElementFactory;
 import com.intellij.psi.impl.source.xml.SchemaPrefix;
 import com.intellij.psi.meta.PsiMetaData;
 import com.intellij.psi.util.PsiTreeUtil;
 import com.intellij.psi.xml.*;
 import com.intellij.util.IncorrectOperationException;
 import com.intellij.xml.XmlAttributeDescriptor;
 import com.intellij.xml.XmlBundle;
 import com.intellij.xml.XmlElementDescriptor;
 import com.intellij.xml.util.ColorSampleLookupValue;
 import com.intellij.xml.util.XmlUtil;
 import org.jetbrains.annotations.NonNls;
 import org.jetbrains.annotations.Nullable;

 import java.util.Collections;
 import java.util.List;
 import java.util.Locale;

 /**
  * @author maxim
  */
 public class HtmlDocumentationProvider implements DocumentationProvider {
   private DocumentationProvider myStyleProvider = null;
   private static DocumentationProvider ourScriptProvider;

   @NonNls public static final String ELEMENT_ELEMENT_NAME = "element";
   @NonNls public static final String NBSP = ":&nbsp;";
   @NonNls public static final String BR = "<br>";

   @Override
   @Nullable
   public String getQuickNavigateInfo(PsiElement element, PsiElement originalElement) {
     if (element instanceof SchemaPrefix) {
       return ((SchemaPrefix)element).getQuickNavigateInfo();
     }
     return null;
   }

   @Override
   public List<String> getUrlFor(PsiElement element, PsiElement originalElement) {
     String result = getUrlForHtml(element, PsiTreeUtil.getParentOfType(originalElement, XmlTag.class, false));
     DocumentationProvider styleProvider = getStyleProvider();
     if (result == null && styleProvider != null) {
       return styleProvider.getUrlFor(element, originalElement);
     }

     return result != null ? Collections.singletonList(result) : null;
   }

   public static String getUrlForHtml(PsiElement element, XmlTag context) {
     final EntityDescriptor descriptor = findDocumentationDescriptor(element, context);

     if (descriptor!=null) {
       return descriptor.getHelpRef();
     } else {
       return null;
     }
   }

   private static EntityDescriptor findDocumentationDescriptor(PsiElement element, XmlTag context) {
     boolean isTag = true;
     PsiElement nameElement = null;
     String key = null;

     if (element instanceof XmlElementDecl) {
       nameElement = ((XmlElementDecl)element).getNameElement();
     } else if (element instanceof XmlAttributeDecl) {
       nameElement = ((XmlAttributeDecl)element).getNameElement();
       isTag = false;
     } else if (element instanceof XmlTag) {
       final XmlTag xmlTag = ((XmlTag)element);
       final PsiMetaData metaData = xmlTag.getMetaData();
       key = (metaData!=null)?metaData.getName():null;
       isTag = xmlTag.getLocalName().equals(ELEMENT_ELEMENT_NAME);
     } else if (element.getParent() instanceof XmlAttributeValue) {
       isTag = false;
       key = ((XmlAttribute)element.getParent().getParent()).getName();
     } else if (element instanceof XmlAttributeValue) {
       isTag = false;
       final XmlAttribute xmlAttribute = (XmlAttribute)element.getParent();
       key = xmlAttribute.getName();
     } else if (element instanceof XmlAttribute) {
       final XmlAttribute xmlAttribute = (XmlAttribute)element;
       isTag = false;
       key = xmlAttribute.getName();
     } else if (element instanceof XmlElement) {
       nameElement = element;
       isTag = !(element.getParent() instanceof XmlAttribute);
     } else {
       nameElement = element;
       if (context == null) {
         isTag = false;
       }
       else {
         String text = element.getText();
         isTag = text != null && text.startsWith(context.getName());
       }
     }

     if (nameElement!=null) {
       key = nameElement.getText();
     }

     key = StringUtil.notNullize(key).toLowerCase(Locale.US);

     int dotIndex = key.indexOf('.');
     if (dotIndex > 0) {
       key = key.substring(0, dotIndex);
     }

     if (isTag) {
       return HtmlDescriptorsTable.getTagDescriptor(key);
     } else {
       return getDescriptor(key, context);
     }
   }

   private static HtmlAttributeDescriptor getDescriptor(String name, XmlTag context) {

     HtmlAttributeDescriptor attributeDescriptor = HtmlDescriptorsTable.getAttributeDescriptor(name);
     if (attributeDescriptor instanceof CompositeAttributeTagDescriptor) {
       return ((CompositeAttributeTagDescriptor)attributeDescriptor).findHtmlAttributeInContext(context);
     }

     return attributeDescriptor;
   }

   @Override
   public String generateDoc(PsiElement element, PsiElement originalElement) {
     final XmlTag tag = PsiTreeUtil.getParentOfType(originalElement, XmlTag.class, false);
     String result = generateDocForHtml(element, false, tag, originalElement);

     DocumentationProvider styleProvider = getStyleProvider();
     if (result == null && styleProvider !=null) {
       result = styleProvider.generateDoc(element, originalElement);
     }

     if (result == null && ourScriptProvider !=null) {
       result = ourScriptProvider.generateDoc(element, originalElement);
     }

     if (result == null && element instanceof XmlAttributeValue) {
       result = generateDocForHtml(element.getParent(), false, tag, originalElement);
     }

     return result;
   }

   protected String generateDocForHtml(PsiElement element, boolean omitHtmlSpecifics, XmlTag context, PsiElement originalElement) {
     final EntityDescriptor descriptor = findDocumentationDescriptor(element,context);

     if (descriptor!=null) {
       return generateJavaDoc(descriptor, omitHtmlSpecifics, originalElement);
     }
     if (element instanceof XmlEntityDecl) {
       final XmlEntityDecl entityDecl = (XmlEntityDecl)element;

       return new XmlDocumentationProvider().findDocRightAfterElement(element, entityDecl.getName());
     }
     return null;
   }

   private static String generateJavaDoc(EntityDescriptor descriptor, boolean omitHtmlSpecifics, PsiElement element) {
     StringBuilder buf = new StringBuilder();
     final boolean isTag = descriptor instanceof HtmlTagDescriptor;

     if (isTag) {
       DocumentationUtil.formatEntityName(XmlBundle.message("xml.javadoc.tag.name.message"),descriptor.getName(),buf);
     } else {
       DocumentationUtil.formatEntityName(XmlBundle.message("xml.javadoc.attribute.name.message"),descriptor.getName(),buf);
     }

     buf.append(XmlBundle.message("xml.javadoc.description.message")).append(NBSP).append(descriptor.getDescription()).append(BR);

     if (isTag) {
       final HtmlTagDescriptor tagDescriptor = (HtmlTagDescriptor)descriptor;

       if (!omitHtmlSpecifics) {
         boolean hasStartTag = tagDescriptor.isHasStartTag();
         if (!hasStartTag) {
           buf.append(XmlBundle.message("xml.javadoc.start.tag.could.be.omitted.message")).append(BR);
         }
         if (!tagDescriptor.isEmpty() && !tagDescriptor.isHasEndTag()) {
           buf.append(XmlBundle.message("xml.javadoc.end.tag.could.be.omitted.message")).append(BR);
         }
       }

       if (tagDescriptor.isEmpty()) {
         buf.append(XmlBundle.message("xml.javadoc.is.empty.message")).append(BR);
       }
     } else {
       final HtmlAttributeDescriptor attributeDescriptor = (HtmlAttributeDescriptor)descriptor;

       buf.append(XmlBundle.message("xml.javadoc.attr.type.message", attributeDescriptor.getType())).append(BR);
       if (!attributeDescriptor.isHasDefaultValue())
         buf.append(XmlBundle.message("xml.javadoc.attr.default.required.message")).append(BR);
     }

     char dtdId = descriptor.getDtd();
     boolean deprecated = dtdId == EntityDescriptor.LOOSE_DTD;
     if (deprecated) {
       buf.append(XmlBundle.message("xml.javadoc.deprecated.message", true)).append(BR);
     }

     if (dtdId == EntityDescriptor.LOOSE_DTD) {
       buf.append(XmlBundle.message("xml.javadoc.defined.in.loose.dtd.message"));
     }
     else if (dtdId == EntityDescriptor.FRAME_DTD) {
       buf.append(XmlBundle.message("xml.javadoc.defined.in.frameset.dtd.message"));
     }
     else {
       buf.append(XmlBundle.message("xml.javadoc.defined.in.any.dtd.message"));
     }

     if (!isTag) {
       ColorSampleLookupValue.addColorPreviewAndCodeToLookup(element,buf);
     }

     if (element != null) {
       buf.append(XmlDocumentationProvider.generateHtmlAdditionalDocTemplate(element));
     }

     return buf.toString();
   }

   @Override
   public PsiElement getDocumentationElementForLookupItem(PsiManager psiManager, Object object, PsiElement element) {
     PsiElement result = createNavigationElementHTML(psiManager, object.toString(),element);

     DocumentationProvider styleProvider = getStyleProvider();
     if (result== null && styleProvider !=null) {
       result = styleProvider.getDocumentationElementForLookupItem(psiManager, object, element);
     }
     if (result== null && ourScriptProvider !=null) {
       result = ourScriptProvider.getDocumentationElementForLookupItem(psiManager, object, element);
     }
     if (result == null && object instanceof String && element != null) {
       result = XmlDocumentationProvider.findDeclWithName((String)object, element);
     }
     return result;
   }

   @Override
   public PsiElement getDocumentationElementForLink(PsiManager psiManager, String link, PsiElement context) {
     PsiElement result = createNavigationElementHTML(psiManager, link, context);

     DocumentationProvider styleProvider = getStyleProvider();
     if (result== null && styleProvider !=null) {
       result = styleProvider.getDocumentationElementForLink(psiManager, link, context);
     }
     if (result== null && ourScriptProvider !=null) {
       result = ourScriptProvider.getDocumentationElementForLink(psiManager, link,context);
     }
     return result;
   }

   public PsiElement createNavigationElementHTML(PsiManager psiManager, String text, PsiElement context) {
     String key = text.toLowerCase(Locale.US);
     final HtmlTagDescriptor descriptor = HtmlDescriptorsTable.getTagDescriptor(key);

     if (descriptor != null && !isAttributeContext(context) ) {
       try {
         final XmlTag tagFromText = XmlElementFactory.getInstance(psiManager.getProject()).createTagFromText("<"+ key + " xmlns=\"" + XmlUtil.XHTML_URI + "\"/>");
         final XmlElementDescriptor tagDescriptor = tagFromText.getDescriptor();
         return tagDescriptor != null ? tagDescriptor.getDeclaration() : null;
       }
       catch(IncorrectOperationException ignore) {
       }
     }
     else {
       XmlTag tagContext = findTagContext(context);
       HtmlAttributeDescriptor myAttributeDescriptor = getDescriptor(key,tagContext);

       if (myAttributeDescriptor != null && tagContext != null) {
         XmlElementDescriptor tagDescriptor = tagContext.getDescriptor();
         XmlAttributeDescriptor attributeDescriptor = tagDescriptor != null ? tagDescriptor.getAttributeDescriptor(text, tagContext): null;

         return (attributeDescriptor != null)?attributeDescriptor.getDeclaration():null;
       }
     }
     return null;
   }

   protected boolean isAttributeContext(PsiElement context) {
     if(context instanceof XmlAttribute) return true;

     if (context instanceof PsiWhiteSpace) {
       PsiElement prevSibling = context.getPrevSibling();
       if (prevSibling instanceof XmlAttribute)
         return true;
     }

     return false;
   }

   protected XmlTag findTagContext(PsiElement context) {
     if (context instanceof PsiWhiteSpace) {
       PsiElement prevSibling = context.getPrevSibling();
       if (prevSibling instanceof XmlTag)
         return (XmlTag)prevSibling;
     }

     return PsiTreeUtil.getParentOfType(context,XmlTag.class,false);
   }

   public static void registerScriptDocumentationProvider(final DocumentationProvider provider) {
     ourScriptProvider = provider;
   }

   @Nullable
   private DocumentationProvider getStyleProvider() {
     if (myStyleProvider == null) {
       Language cssLanguage = Language.findLanguageByID("CSS");
       if (cssLanguage != null) {
         myStyleProvider = LanguageDocumentation.INSTANCE.forLanguage(cssLanguage);
       }
     }
     return myStyleProvider;
   }
 }
	/*
	* Copyright 2000-2014 JetBrains s.r.o.
	*
	* 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 com.intellij.xml.util.documentation;

	import com.intellij.lang.Language;
	import com.intellij.lang.LanguageDocumentation;
	import com.intellij.lang.documentation.DocumentationProvider;
	import com.intellij.lang.documentation.DocumentationUtil;
	import com.intellij.openapi.util.text.StringUtil;
	import com.intellij.psi.PsiElement;
	import com.intellij.psi.PsiManager;
	import com.intellij.psi.PsiWhiteSpace;
	import com.intellij.psi.XmlElementFactory;
	import com.intellij.psi.impl.source.xml.SchemaPrefix;
	import com.intellij.psi.meta.PsiMetaData;
	import com.intellij.psi.util.PsiTreeUtil;
	import com.intellij.psi.xml.*;
	import com.intellij.util.IncorrectOperationException;
	import com.intellij.xml.XmlAttributeDescriptor;
	import com.intellij.xml.XmlBundle;
	import com.intellij.xml.XmlElementDescriptor;
	import com.intellij.xml.util.ColorSampleLookupValue;
	import com.intellij.xml.util.XmlUtil;
	import org.jetbrains.annotations.NonNls;
	import org.jetbrains.annotations.Nullable;

	import java.util.Collections;
	import java.util.List;
	import java.util.Locale;

	/**
	* @author maxim
	*/
	public class HtmlDocumentationProvider implements DocumentationProvider {
	private DocumentationProvider myStyleProvider = null;
	private static DocumentationProvider ourScriptProvider;

	@NonNls public static final String ELEMENT_ELEMENT_NAME = "element";
	@NonNls public static final String NBSP = ": ";
	@NonNls public static final String BR = "<br>";

	@Override
	@Nullable
	public String getQuickNavigateInfo(PsiElement element, PsiElement originalElement) {
	if (element instanceof SchemaPrefix) {
	return ((SchemaPrefix)element).getQuickNavigateInfo();
	}
	return null;
	}

	@Override
	public List<String> getUrlFor(PsiElement element, PsiElement originalElement) {
	String result = getUrlForHtml(element, PsiTreeUtil.getParentOfType(originalElement, XmlTag.class, false));
	DocumentationProvider styleProvider = getStyleProvider();
	if (result == null && styleProvider != null) {
	return styleProvider.getUrlFor(element, originalElement);
	}

	return result != null ? Collections.singletonList(result) : null;
	}

	public static String getUrlForHtml(PsiElement element, XmlTag context) {
	final EntityDescriptor descriptor = findDocumentationDescriptor(element, context);

	if (descriptor!=null) {
	return descriptor.getHelpRef();
	} else {
	return null;
	}
	}

	private static EntityDescriptor findDocumentationDescriptor(PsiElement element, XmlTag context) {
	boolean isTag = true;
	PsiElement nameElement = null;
	String key = null;

	if (element instanceof XmlElementDecl) {
	nameElement = ((XmlElementDecl)element).getNameElement();
	} else if (element instanceof XmlAttributeDecl) {
	nameElement = ((XmlAttributeDecl)element).getNameElement();
	isTag = false;
	} else if (element instanceof XmlTag) {
	final XmlTag xmlTag = ((XmlTag)element);
	final PsiMetaData metaData = xmlTag.getMetaData();
	key = (metaData!=null)?metaData.getName():null;
	isTag = xmlTag.getLocalName().equals(ELEMENT_ELEMENT_NAME);
	} else if (element.getParent() instanceof XmlAttributeValue) {
	isTag = false;
	key = ((XmlAttribute)element.getParent().getParent()).getName();
	} else if (element instanceof XmlAttributeValue) {
	isTag = false;
	final XmlAttribute xmlAttribute = (XmlAttribute)element.getParent();
	key = xmlAttribute.getName();
	} else if (element instanceof XmlAttribute) {
	final XmlAttribute xmlAttribute = (XmlAttribute)element;
	isTag = false;
	key = xmlAttribute.getName();
	} else if (element instanceof XmlElement) {
	nameElement = element;
	isTag = !(element.getParent() instanceof XmlAttribute);
	} else {
	nameElement = element;
	if (context == null) {
	isTag = false;
	}
	else {
	String text = element.getText();
	isTag = text != null && text.startsWith(context.getName());
	}
	}

	if (nameElement!=null) {
	key = nameElement.getText();
	}

	key = StringUtil.notNullize(key).toLowerCase(Locale.US);

	int dotIndex = key.indexOf('.');
	if (dotIndex > 0) {
	key = key.substring(0, dotIndex);
	}

	if (isTag) {
	return HtmlDescriptorsTable.getTagDescriptor(key);
	} else {
	return getDescriptor(key, context);
	}
	}

	private static HtmlAttributeDescriptor getDescriptor(String name, XmlTag context) {

	HtmlAttributeDescriptor attributeDescriptor = HtmlDescriptorsTable.getAttributeDescriptor(name);
	if (attributeDescriptor instanceof CompositeAttributeTagDescriptor) {
	return ((CompositeAttributeTagDescriptor)attributeDescriptor).findHtmlAttributeInContext(context);
	}

	return attributeDescriptor;
	}

	@Override
	public String generateDoc(PsiElement element, PsiElement originalElement) {
	final XmlTag tag = PsiTreeUtil.getParentOfType(originalElement, XmlTag.class, false);
	String result = generateDocForHtml(element, false, tag, originalElement);

	DocumentationProvider styleProvider = getStyleProvider();
	if (result == null && styleProvider !=null) {
	result = styleProvider.generateDoc(element, originalElement);
	}

	if (result == null && ourScriptProvider !=null) {
	result = ourScriptProvider.generateDoc(element, originalElement);
	}

	if (result == null && element instanceof XmlAttributeValue) {
	result = generateDocForHtml(element.getParent(), false, tag, originalElement);
	}

	return result;
	}

	protected String generateDocForHtml(PsiElement element, boolean omitHtmlSpecifics, XmlTag context, PsiElement originalElement) {
	final EntityDescriptor descriptor = findDocumentationDescriptor(element,context);

	if (descriptor!=null) {
	return generateJavaDoc(descriptor, omitHtmlSpecifics, originalElement);
	}
	if (element instanceof XmlEntityDecl) {
	final XmlEntityDecl entityDecl = (XmlEntityDecl)element;

	return new XmlDocumentationProvider().findDocRightAfterElement(element, entityDecl.getName());
	}
	return null;
	}

	private static String generateJavaDoc(EntityDescriptor descriptor, boolean omitHtmlSpecifics, PsiElement element) {
	StringBuilder buf = new StringBuilder();
	final boolean isTag = descriptor instanceof HtmlTagDescriptor;

	if (isTag) {
	DocumentationUtil.formatEntityName(XmlBundle.message("xml.javadoc.tag.name.message"),descriptor.getName(),buf);
	} else {
	DocumentationUtil.formatEntityName(XmlBundle.message("xml.javadoc.attribute.name.message"),descriptor.getName(),buf);
	}

	buf.append(XmlBundle.message("xml.javadoc.description.message")).append(NBSP).append(descriptor.getDescription()).append(BR);

	if (isTag) {
	final HtmlTagDescriptor tagDescriptor = (HtmlTagDescriptor)descriptor;

	if (!omitHtmlSpecifics) {
	boolean hasStartTag = tagDescriptor.isHasStartTag();
	if (!hasStartTag) {
	buf.append(XmlBundle.message("xml.javadoc.start.tag.could.be.omitted.message")).append(BR);
	}
	if (!tagDescriptor.isEmpty() && !tagDescriptor.isHasEndTag()) {
	buf.append(XmlBundle.message("xml.javadoc.end.tag.could.be.omitted.message")).append(BR);
	}
	}

	if (tagDescriptor.isEmpty()) {
	buf.append(XmlBundle.message("xml.javadoc.is.empty.message")).append(BR);
	}
	} else {
	final HtmlAttributeDescriptor attributeDescriptor = (HtmlAttributeDescriptor)descriptor;

	buf.append(XmlBundle.message("xml.javadoc.attr.type.message", attributeDescriptor.getType())).append(BR);
	if (!attributeDescriptor.isHasDefaultValue())
	buf.append(XmlBundle.message("xml.javadoc.attr.default.required.message")).append(BR);
	}

	char dtdId = descriptor.getDtd();
	boolean deprecated = dtdId == EntityDescriptor.LOOSE_DTD;
	if (deprecated) {
	buf.append(XmlBundle.message("xml.javadoc.deprecated.message", true)).append(BR);
	}

	if (dtdId == EntityDescriptor.LOOSE_DTD) {
	buf.append(XmlBundle.message("xml.javadoc.defined.in.loose.dtd.message"));
	}
	else if (dtdId == EntityDescriptor.FRAME_DTD) {
	buf.append(XmlBundle.message("xml.javadoc.defined.in.frameset.dtd.message"));
	}
	else {
	buf.append(XmlBundle.message("xml.javadoc.defined.in.any.dtd.message"));
	}

	if (!isTag) {
	ColorSampleLookupValue.addColorPreviewAndCodeToLookup(element,buf);
	}

	if (element != null) {
	buf.append(XmlDocumentationProvider.generateHtmlAdditionalDocTemplate(element));
	}

	return buf.toString();
	}

	@Override
	public PsiElement getDocumentationElementForLookupItem(PsiManager psiManager, Object object, PsiElement element) {
	PsiElement result = createNavigationElementHTML(psiManager, object.toString(),element);

	DocumentationProvider styleProvider = getStyleProvider();
	if (result== null && styleProvider !=null) {
	result = styleProvider.getDocumentationElementForLookupItem(psiManager, object, element);
	}
	if (result== null && ourScriptProvider !=null) {
	result = ourScriptProvider.getDocumentationElementForLookupItem(psiManager, object, element);
	}
	if (result == null && object instanceof String && element != null) {
	result = XmlDocumentationProvider.findDeclWithName((String)object, element);
	}
	return result;
	}

	@Override
	public PsiElement getDocumentationElementForLink(PsiManager psiManager, String link, PsiElement context) {
	PsiElement result = createNavigationElementHTML(psiManager, link, context);

	DocumentationProvider styleProvider = getStyleProvider();
	if (result== null && styleProvider !=null) {
	result = styleProvider.getDocumentationElementForLink(psiManager, link, context);
	}
	if (result== null && ourScriptProvider !=null) {
	result = ourScriptProvider.getDocumentationElementForLink(psiManager, link,context);
	}
	return result;
	}

	public PsiElement createNavigationElementHTML(PsiManager psiManager, String text, PsiElement context) {
	String key = text.toLowerCase(Locale.US);
	final HtmlTagDescriptor descriptor = HtmlDescriptorsTable.getTagDescriptor(key);

	if (descriptor != null && !isAttributeContext(context) ) {
	try {
	final XmlTag tagFromText = XmlElementFactory.getInstance(psiManager.getProject()).createTagFromText("<"+ key + " xmlns=\"" + XmlUtil.XHTML_URI + "\"/>");
	final XmlElementDescriptor tagDescriptor = tagFromText.getDescriptor();
	return tagDescriptor != null ? tagDescriptor.getDeclaration() : null;
	}
	catch(IncorrectOperationException ignore) {
	}
	}
	else {
	XmlTag tagContext = findTagContext(context);
	HtmlAttributeDescriptor myAttributeDescriptor = getDescriptor(key,tagContext);

	if (myAttributeDescriptor != null && tagContext != null) {
	XmlElementDescriptor tagDescriptor = tagContext.getDescriptor();
	XmlAttributeDescriptor attributeDescriptor = tagDescriptor != null ? tagDescriptor.getAttributeDescriptor(text, tagContext): null;

	return (attributeDescriptor != null)?attributeDescriptor.getDeclaration():null;
	}
	}
	return null;
	}

	protected boolean isAttributeContext(PsiElement context) {
	if(context instanceof XmlAttribute) return true;

	if (context instanceof PsiWhiteSpace) {
	PsiElement prevSibling = context.getPrevSibling();
	if (prevSibling instanceof XmlAttribute)
	return true;
	}

	return false;
	}

	protected XmlTag findTagContext(PsiElement context) {
	if (context instanceof PsiWhiteSpace) {
	PsiElement prevSibling = context.getPrevSibling();
	if (prevSibling instanceof XmlTag)
	return (XmlTag)prevSibling;
	}

	return PsiTreeUtil.getParentOfType(context,XmlTag.class,false);
	}

	public static void registerScriptDocumentationProvider(final DocumentationProvider provider) {
	ourScriptProvider = provider;
	}

	@Nullable
	private DocumentationProvider getStyleProvider() {
	if (myStyleProvider == null) {
	Language cssLanguage = Language.findLanguageByID("CSS");
	if (cssLanguage != null) {
	myStyleProvider = LanguageDocumentation.INSTANCE.forLanguage(cssLanguage);
	}
	}
	return myStyleProvider;
	}
	}