/*
    * Copyright (c) 2002-2011 Gargoyle Software Inc.
    *
    * 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.gargoylesoftware.htmlunit.javascript.host;
  
  import java.io.IOException;
  
  import net.sourceforge.htmlunit.corejs.javascript.Context;
  
  import org.apache.commons.logging.Log;
  import org.apache.commons.logging.LogFactory;
  
  import com.gargoylesoftware.htmlunit.BrowserVersion;
  import com.gargoylesoftware.htmlunit.BrowserVersionFeatures;
  import com.gargoylesoftware.htmlunit.ElementNotFoundException;
  import com.gargoylesoftware.htmlunit.SgmlPage;
  import com.gargoylesoftware.htmlunit.html.DomComment;
  import com.gargoylesoftware.htmlunit.html.DomDocumentFragment;
  import com.gargoylesoftware.htmlunit.html.DomElement;
  import com.gargoylesoftware.htmlunit.html.DomNode;
  import com.gargoylesoftware.htmlunit.html.DomText;
  import com.gargoylesoftware.htmlunit.html.FrameWindow;
  import com.gargoylesoftware.htmlunit.html.HTMLParser;
  import com.gargoylesoftware.htmlunit.html.HtmlDivision;
  import com.gargoylesoftware.htmlunit.html.HtmlPage;
  import com.gargoylesoftware.htmlunit.html.impl.SimpleRange;
  import com.gargoylesoftware.htmlunit.javascript.SimpleScriptable;
  import com.gargoylesoftware.htmlunit.javascript.host.html.HTMLCollection;
  import com.gargoylesoftware.htmlunit.javascript.host.html.HTMLElement;
  import com.gargoylesoftware.htmlunit.xml.XmlUtil;
  
  /**
   * A JavaScript object for a Document.
   *
   * @version $Revision: 6472 $
   * @author <a href="mailto:mbowler@GargoyleSoftware.com">Mike Bowler</a>
   * @author David K. Taylor
   * @author <a href="mailto:chen_jun@users.sourceforge.net">Chen Jun</a>
   * @author <a href="mailto:cse@dynabean.de">Christian Sell</a>
   * @author Chris Erskine
   * @author Marc Guillemot
   * @author Daniel Gredler
   * @author Michael Ottati
   * @author <a href="mailto:george@murnock.com">George Murnock</a>
   * @author Ahmed Ashour
   * @author Rob Di Marco
   * @see <a href="http://msdn.microsoft.com/en-us/library/ms531073.aspx">MSDN documentation</a>
   * @see <a href="http://www.w3.org/TR/2000/WD-DOM-Level-1-20000929/level-one-html.html#ID-7068919">W3C Dom Level 1</a>
   */
  public class Document extends EventNode {
  
      private static final Log LOG = LogFactory.getLog(Document.class);
  
      private Window window_;
      private DOMImplementation implementation_;
      private String designMode_;
  
      /**
       * Sets the Window JavaScript object that encloses this document.
       * @param window the Window JavaScript object that encloses this document
       */
      public void setWindow(final Window window) {
          window_ = window;
      }
  
      /**
       * Returns the value of the "location" property.
       * @return the value of the "location" property
       */
      public Location jsxGet_location() {
          return window_.jsxGet_location();
      }
  
      /**
       * Sets the value of the "location" property. The location's default property is "href",
       * so setting "document.location='http://www.sf.net'" is equivalent to setting
       * "document.location.href='http://www.sf.net'".
       * @see <a href="http://msdn.microsoft.com/en-us/library/ms535866.aspx">MSDN documentation</a>
       * @param location the location to navigate to
       * @throws IOException when location loading fails
       */
      public void jsxSet_location(final String location) throws IOException {
          window_.jsxSet_location(location);
      }
  
      /**
       * Returns the value of the "referrer" property.
       * @return the value of the "referrer" property
      */
     public String jsxGet_referrer() {
         final String referrer = getPage().getWebResponse().getWebRequest().getAdditionalHeaders().get("Referer");
         if (referrer == null) {
             return "";
         }
         return referrer;
     }
 
     /**
      * Gets the JavaScript property "documentElement" for the document.
      * @return the root node for the document
      */
     public Element jsxGet_documentElement() {
         final Object documentElement = getPage().getDocumentElement();
         if (documentElement == null) {
             // for instance with an XML document with parsing error
             return null;
         }
         return (Element) getScriptableFor(documentElement);
     }
 
     /**
      * Gets the JavaScript property "doctype" for the document.
      * @return the DocumentType of the document
      */
     public SimpleScriptable jsxGet_doctype() {
         final Object documentType = getPage().getDoctype();
         if (documentType == null) {
             return null;
         }
         return getScriptableFor(documentType);
     }
 
     /**
      * Returns a value which indicates whether or not the document can be edited.
      * @return a value which indicates whether or not the document can be edited
      */
     public String jsxGet_designMode() {
         if (designMode_ == null) {
             if (getBrowserVersion().hasFeature(BrowserVersionFeatures.GENERATED_30)) {
                 if (getWindow().getWebWindow() instanceof FrameWindow) {
                     designMode_ = "Inherit";
                 }
                 else {
                     designMode_ = "Off";
                 }
             }
             else {
                 designMode_ = "off";
             }
         }
         return designMode_;
     }
 
     /**
      * Sets a value which indicates whether or not the document can be edited.
      * @param mode a value which indicates whether or not the document can be edited
      */
     public void jsxSet_designMode(final String mode) {
         final boolean ie = getBrowserVersion().hasFeature(BrowserVersionFeatures.GENERATED_31);
         if (ie) {
             if (!"on".equalsIgnoreCase(mode) && !"off".equalsIgnoreCase(mode) && !"inherit".equalsIgnoreCase(mode)) {
                 throw Context.reportRuntimeError("Invalid document.designMode value '" + mode + "'.");
             }
             else if (!(getWindow().getWebWindow() instanceof FrameWindow)) {
                 // IE ignores designMode changes for documents that aren't in frames.
                 return;
             }
             else if ("on".equalsIgnoreCase(mode)) {
                 designMode_ = "On";
             }
             else if ("off".equalsIgnoreCase(mode)) {
                 designMode_ = "Off";
             }
             else if ("inherit".equalsIgnoreCase(mode)) {
                 designMode_ = "Inherit";
             }
         }
         else {
             if ("on".equalsIgnoreCase(mode)) {
                 designMode_ = "on";
                 final SgmlPage page = getPage();
                 if (page instanceof HtmlPage) {
                     final HtmlPage htmlPage = (HtmlPage) page;
                     final DomNode child = htmlPage.getBody().getFirstChild();
                     final DomNode rangeNode = child != null ? child : htmlPage.getBody();
                     htmlPage.setSelectionRange(new SimpleRange(rangeNode, 0));
                 }
             }
             else if ("off".equalsIgnoreCase(mode)) {
                 designMode_ = "off";
             }
         }
     }
 
     /**
      * Returns the page that this document is modeling.
      * @return the page that this document is modeling
      */
     protected SgmlPage getPage() {
         return (SgmlPage) getDomNodeOrDie();
     }
 
     /**
      * Gets the window in which this document is contained.
      * @return the window
      */
     public Object jsxGet_defaultView() {
         return getWindow();
     }
 
     /**
      * Creates a new document fragment.
      * @return a newly created document fragment
      */
     public Object jsxFunction_createDocumentFragment() {
         final DomDocumentFragment fragment = this.<DomNode>getDomNodeOrDie().getPage().createDomDocumentFragment();
         final DocumentFragment node = new DocumentFragment();
         node.setParentScope(getParentScope());
         node.setPrototype(getPrototype(node.getClass()));
         node.setDomNode(fragment);
         return getScriptableFor(fragment);
     }
 
     /**
      * Creates a new HTML attribute with the specified name.
      *
      * @param attributeName the name of the attribute to create
      * @return an attribute with the specified name
      */
     public Attr jsxFunction_createAttribute(final String attributeName) {
         return (Attr) getPage().createAttribute(attributeName).getScriptObject();
     }
 
     /**
      * Returns the {@link BoxObject} for the specific element.
      *
      * @param element target for BoxObject
      * @return the BoxObject
      */
     public BoxObject jsxFunction_getBoxObjectFor(final HTMLElement element) {
         return element.getBoxObject();
     }
 
     /**
      * Imports a node from another document to this document.
      * The source node is not altered or removed from the original document;
      * this method creates a new copy of the source node.
      *
      * @param importedNode the node to import
      * @param deep Whether to recursively import the subtree under the specified node; or not
      * @return the imported node that belongs to this Document
      */
     public Object jsxFunction_importNode(final Node importedNode, final boolean deep) {
         return importedNode.<DomNode>getDomNodeOrDie().cloneNode(deep).getScriptObject();
     }
 
     /**
      * Returns the implementation object of the current document.
      * @return implementation-specific object
      */
     public DOMImplementation jsxGet_implementation() {
         if (implementation_ == null) {
             implementation_ = new DOMImplementation();
             implementation_.setParentScope(getWindow());
             implementation_.setPrototype(getPrototype(implementation_.getClass()));
         }
         return implementation_;
     }
 
     /**
      * Does nothing special anymore... just like FF.
      * @param type the type of events to capture
      * @see Window#jsxFunction_captureEvents(String)
      */
     public void jsxFunction_captureEvents(final String type) {
         // Empty.
     }
 
     /**
      * Adapts any DOM node to resolve namespaces so that an XPath expression can be easily
      * evaluated relative to the context of the node where it appeared within the document.
      * @param nodeResolver the node to be used as a context for namespace resolution
      * @return an XPathNSResolver which resolves namespaces with respect to the definitions
      *         in scope for a specified node
      */
     public XPathNSResolver jsxFunction_createNSResolver(final Node nodeResolver) {
         final XPathNSResolver resolver = new XPathNSResolver();
         resolver.setElement(nodeResolver);
         resolver.setParentScope(getWindow());
         resolver.setPrototype(getPrototype(resolver.getClass()));
         return resolver;
     }
 
     /**
      * Create a new DOM text node with the given data.
      *
      * @param newData the string value for the text node
      * @return the new text node or NOT_FOUND if there is an error
      */
     public Object jsxFunction_createTextNode(final String newData) {
         Object result = NOT_FOUND;
         try {
             final DomNode domNode = new DomText(this.<DomNode>getDomNodeOrDie().getPage(), newData);
             final Object jsElement = getScriptableFor(domNode);
 
             if (jsElement == NOT_FOUND) {
                 if (LOG.isDebugEnabled()) {
                     LOG.debug("createTextNode(" + newData
                             + ") cannot return a result as there isn't a JavaScript object for the DOM node "
                             + domNode.getClass().getName());
                 }
             }
             else {
                 result = jsElement;
             }
         }
         catch (final ElementNotFoundException e) {
             // Just fall through - result is already set to NOT_FOUND
         }
         return result;
     }
 
     /**
      * Creates a new Comment.
      * @param comment the comment text
      * @return the new Comment
      */
     public Object jsxFunction_createComment(final String comment) {
         final DomNode domNode = new DomComment(this.<DomNode>getDomNodeOrDie().getPage(), comment);
         return getScriptableFor(domNode);
     }
 
     /**
      * Evaluates an XPath expression string and returns a result of the specified type if possible.
      * @param expression the XPath expression string to be parsed and evaluated
      * @param contextNode the context node for the evaluation of this XPath expression
      * @param resolver the resolver permits translation of all prefixes, including the XML namespace prefix,
      *        within the XPath expression into appropriate namespace URIs.
      * @param type If a specific type is specified, then the result will be returned as the corresponding type
      * @param result the result object which may be reused and returned by this method
      * @return the result of the evaluation of the XPath expression
      */
     public XPathResult jsxFunction_evaluate(final String expression, final Node contextNode,
             final Object resolver, final int type, final Object result) {
         XPathResult xPathResult = (XPathResult) result;
         if (xPathResult == null) {
             xPathResult = new XPathResult();
             xPathResult.setParentScope(getParentScope());
             xPathResult.setPrototype(getPrototype(xPathResult.getClass()));
         }
         xPathResult.init(contextNode.<DomNode>getDomNodeOrDie().getByXPath(expression), type);
         return xPathResult;
     }
 
     /**
      * Create a new HTML element with the given tag name.
      *
      * @param tagName the tag name
      * @return the new HTML element, or NOT_FOUND if the tag is not supported
      */
     public Object jsxFunction_createElement(String tagName) {
         Object result = NOT_FOUND;
         try {
             final BrowserVersion browserVersion = getBrowserVersion();
 
             if (tagName.startsWith("<") && tagName.endsWith(">")
                     && browserVersion.hasFeature(BrowserVersionFeatures.GENERATED_153)) {
                 tagName = tagName.substring(1, tagName.length() - 1);
                 if (!tagName.matches("\\w+")) {
                     LOG.error("Unexpected exception occurred while parsing HTML snippet");
                     throw Context.reportRuntimeError("Unexpected exception occurred while parsing HTML snippet: "
                             + tagName);
                 }
             }
 
             final SgmlPage page = getPage();
             final org.w3c.dom.Element element = page.createElement(tagName);
             final Object jsElement = getScriptableFor(element);
 
             if (jsElement == NOT_FOUND) {
                 if (LOG.isDebugEnabled()) {
                     LOG.debug("createElement(" + tagName
                         + ") cannot return a result as there isn't a JavaScript object for the element "
                         + element.getClass().getName());
                 }
             }
             else {
                 result = jsElement;
             }
         }
         catch (final ElementNotFoundException e) {
             // Just fall through - result is already set to NOT_FOUND
         }
         return result;
     }
 
     /**
      * Creates a new HTML element with the given tag name, and name.
      *
      * @param namespaceURI the URI that identifies an XML namespace
      * @param qualifiedName the qualified name of the element type to instantiate
      * @return the new HTML element, or NOT_FOUND if the tag is not supported
      */
     public Object jsxFunction_createElementNS(final String namespaceURI, final String qualifiedName) {
         final org.w3c.dom.Element element;
         final BrowserVersion browserVersion = getBrowserVersion();
         if (browserVersion.hasFeature(BrowserVersionFeatures.XUL_SUPPORT)
                 && "http://www.mozilla.org/keymaster/gatekeeper/there.is.only.xul".equals(namespaceURI)) {
             // simple hack, no need to implement the XUL objects (at least in a first time)
             element = new HtmlDivision(namespaceURI, qualifiedName, getPage(), null);
         }
         else if (HTMLParser.XHTML_NAMESPACE.equals(namespaceURI)) {
             element = getPage().createElementNS(namespaceURI, qualifiedName);
         }
         else {
             element = new DomElement(namespaceURI, qualifiedName, getPage(), null);
         }
         return getScriptableFor(element);
     }
 
     /**
      * Returns all the descendant elements with the specified tag name.
      * @param tagName the name to search for
      * @return all the descendant elements with the specified tag name
      */
     public HTMLCollection jsxFunction_getElementsByTagName(final String tagName) {
         final String description = "Document.getElementsByTagName('" + tagName + "')";
 
         final HTMLCollection collection;
         if ("*".equals(tagName)) {
             collection = new HTMLCollection(getDomNodeOrDie(), false, description) {
                 @Override
                 protected boolean isMatching(final DomNode node) {
                     return true;
                 }
             };
         }
         else {
             final boolean useLocalName = getBrowserVersion().hasFeature(BrowserVersionFeatures.GENERATED_32);
             final String tagNameLC = tagName.toLowerCase();
 
             collection = new HTMLCollection(getDomNodeOrDie(), false, description) {
                 @Override
                 protected boolean isMatching(final DomNode node) {
                     if (useLocalName) {
                         return tagNameLC.equalsIgnoreCase(node.getLocalName());
                     }
                     return tagNameLC.equalsIgnoreCase(node.getNodeName());
                 }
             };
         }
 
         return collection;
     }
 
     /**
      * Returns a list of elements with the given tag name belonging to the given namespace.
      * @param namespaceURI the namespace URI of elements to look for
      * @param localName is either the local name of elements to look for or the special value "*",
      *                  which matches all elements.
      * @return a live NodeList of found elements in the order they appear in the tree
      */
     public Object jsxFunction_getElementsByTagNameNS(final Object namespaceURI, final String localName) {
         final String description = "Document.getElementsByTagNameNS('" + namespaceURI + "', '" + localName + "')";
         final DomElement domNode = getPage().getDocumentElement();
 
         final String prefix;
         if (namespaceURI != null && !"*".equals("*")) {
             prefix = XmlUtil.lookupPrefix(domNode, Context.toString(namespaceURI));
         }
         else {
             prefix = null;
         }
 
         final HTMLCollection collection = new HTMLCollection(domNode, false, description) {
             @Override
             protected boolean isMatching(final DomNode node) {
                 if (!localName.equals(node.getLocalName())) {
                     return false;
                 }
                 if (prefix == null) {
                     return true;
                 }
                 return true;
             }
         };
 
         return collection;
     }
 }