gecko/content/base/src/nsStyledElement.cpp

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/* ***** BEGIN LICENSE BLOCK *****
 * Version: MPL 1.1/GPL 2.0/LGPL 2.1
 *
 * The contents of this file are subject to the Mozilla Public License Version
 * 1.1 (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 Mozilla Communicator client code.
 *
 * The Initial Developer of the Original Code is
 * Netscape Communications Corporation.
 * Portions created by the Initial Developer are Copyright (C) 1998
 * the Initial Developer. All Rights Reserved.
 *
 * Contributor(s):
 *   Mats Palmgren <mats.palmgren@bredband.net>
 *   Daniel Kraft <d@domob.eu>
 *
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 * either of the GNU General Public License Version 2 or later (the "GPL"),
 * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
 * in which case the provisions of the GPL or the LGPL are applicable instead
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#include "nsStyledElement.h"
#include "nsGkAtoms.h"
#include "nsAttrValue.h"
#include "nsGenericElement.h"
#include "nsMutationEvent.h"
#include "nsDOMCSSDeclaration.h"
#include "nsDOMCSSAttrDeclaration.h"
#include "nsServiceManagerUtils.h"
#include "nsIDocument.h"
#include "mozilla/css/StyleRule.h"
#include "nsCSSParser.h"
#include "mozilla/css/Loader.h"
#include "nsIDOMMutationEvent.h"
#include "nsXULElement.h"
#include "nsIDOMSVGStylable.h"
#include "nsContentUtils.h"

namespace css = mozilla::css;

//----------------------------------------------------------------------
// nsIContent methods

nsIAtom*
nsStyledElementNotElementCSSInlineStyle::GetClassAttributeName() const
{
  return nsGkAtoms::_class;
}

nsIAtom*
nsStyledElementNotElementCSSInlineStyle::GetIDAttributeName() const
{
  return nsGkAtoms::id;
}

nsIAtom*
nsStyledElementNotElementCSSInlineStyle::DoGetID() const
{
  NS_ASSERTION(HasID(), "Unexpected call");

  // The nullcheck here is needed because nsGenericElement::UnsetAttr calls
  // out to various code between removing the attribute and we get a chance to
  // ClearHasID().

  const nsAttrValue* attr = mAttrsAndChildren.GetAttr(nsGkAtoms::id);

  return attr ? attr->GetAtomValue() : nsnull;
}

const nsAttrValue*
nsStyledElementNotElementCSSInlineStyle::DoGetClasses() const
{
  NS_ASSERTION(HasFlag(NODE_MAY_HAVE_CLASS), "Unexpected call");
  return mAttrsAndChildren.GetAttr(nsGkAtoms::_class);
}

bool
nsStyledElementNotElementCSSInlineStyle::ParseAttribute(PRInt32 aNamespaceID,
                                                        nsIAtom* aAttribute,
                                                        const nsAString& aValue,
                                                        nsAttrValue& aResult)
{
  if (aNamespaceID == kNameSpaceID_None) {
    if (aAttribute == nsGkAtoms::style) {
      SetMayHaveStyle();
      ParseStyleAttribute(aValue, aResult, false);
      return true;
    }
    if (aAttribute == nsGkAtoms::_class) {
      SetFlags(NODE_MAY_HAVE_CLASS);
      aResult.ParseAtomArray(aValue);
      return true;
    }
    if (aAttribute == nsGkAtoms::id) {
      // Store id as an atom.  id="" means that the element has no id,
      // not that it has an emptystring as the id.
      RemoveFromIdTable();
      if (aValue.IsEmpty()) {
        ClearHasID();
        return false;
      }
      aResult.ParseAtom(aValue);
      SetHasID();
      AddToIdTable(aResult.GetAtomValue());
      return true;
    }
  }

  return nsStyledElementBase::ParseAttribute(aNamespaceID, aAttribute, aValue,
                                             aResult);
}

nsresult
nsStyledElementNotElementCSSInlineStyle::UnsetAttr(PRInt32 aNameSpaceID,
                                                   nsIAtom* aAttribute,
                                                   bool aNotify)
{
  nsAutoScriptBlocker scriptBlocker;
  if (aAttribute == nsGkAtoms::id && aNameSpaceID == kNameSpaceID_None) {
    // Have to do this before clearing flag. See RemoveFromIdTable
    RemoveFromIdTable();
  }

  return nsGenericElement::UnsetAttr(aNameSpaceID, aAttribute, aNotify);
}

nsresult
nsStyledElementNotElementCSSInlineStyle::AfterSetAttr(PRInt32 aNamespaceID,
                                                      nsIAtom* aAttribute,
                                                      const nsAttrValue* aValue,
                                                      bool aNotify)
{
  if (aNamespaceID == kNameSpaceID_None && !aValue &&
      aAttribute == nsGkAtoms::id) {
    // The id has been removed when calling UnsetAttr but we kept it because
    // the id is used for some layout stuff between UnsetAttr and AfterSetAttr.
    // Now. the id is really removed so it would not be safe to keep this flag.
    ClearHasID();
  }

  return nsGenericElement::AfterSetAttr(aNamespaceID, aAttribute, aValue,
                                        aNotify);
}

NS_IMETHODIMP
nsStyledElementNotElementCSSInlineStyle::SetInlineStyleRule(css::StyleRule* aStyleRule,
                                                            const nsAString* aSerialized,
                                                            bool aNotify)
{
  SetMayHaveStyle();
  bool modification = false;
  nsAttrValue oldValue;

  bool hasListeners = aNotify &&
    nsContentUtils::HasMutationListeners(this,
                                         NS_EVENT_BITS_MUTATION_ATTRMODIFIED,
                                         this);

  // There's no point in comparing the stylerule pointers since we're always
  // getting a new stylerule here. And we can't compare the stringvalues of
  // the old and the new rules since both will point to the same declaration
  // and thus will be the same.
  if (hasListeners) {
    // save the old attribute so we can set up the mutation event properly
    // XXXbz if the old rule points to the same declaration as the new one,
    // this is getting the new attr value, not the old one....
    nsAutoString oldValueStr;
    modification = GetAttr(kNameSpaceID_None, nsGkAtoms::style,
                           oldValueStr);
    if (modification) {
      oldValue.SetTo(oldValueStr);
    }
  }
  else if (aNotify && IsInDoc()) {
    modification = !!mAttrsAndChildren.GetAttr(nsGkAtoms::style);
  }

  nsAttrValue attrValue(aStyleRule, aSerialized);

  // XXXbz do we ever end up with ADDITION here?  I doubt it.
  PRUint8 modType = modification ?
    static_cast<PRUint8>(nsIDOMMutationEvent::MODIFICATION) :
    static_cast<PRUint8>(nsIDOMMutationEvent::ADDITION);

  return SetAttrAndNotify(kNameSpaceID_None, nsGkAtoms::style, nsnull,
                          oldValue, attrValue, modType, hasListeners,
                          aNotify, kDontCallAfterSetAttr);
}

css::StyleRule*
nsStyledElementNotElementCSSInlineStyle::GetInlineStyleRule()
{
  if (!MayHaveStyle()) {
    return nsnull;
  }
  const nsAttrValue* attrVal = mAttrsAndChildren.GetAttr(nsGkAtoms::style);

  if (attrVal && attrVal->Type() == nsAttrValue::eCSSStyleRule) {
    return attrVal->GetCSSStyleRuleValue();
  }

  return nsnull;
}

// ---------------------------------------------------------------
// Others and helpers

nsIDOMCSSStyleDeclaration*
nsStyledElementNotElementCSSInlineStyle::GetStyle(nsresult* retval)
{
  nsXULElement* xulElement = nsXULElement::FromContent(this);
  if (xulElement) {
    nsresult rv = xulElement->EnsureLocalStyle();
    if (NS_FAILED(rv)) {
      *retval = rv;
      return nsnull;
    }
  }
    
  nsGenericElement::nsDOMSlots *slots = DOMSlots();

  if (!slots->mStyle) {
    // Just in case...
    ReparseStyleAttribute(true);

    slots->mStyle = new nsDOMCSSAttributeDeclaration(this, false);
    SetMayHaveStyle();
  }

  *retval = NS_OK;
  return slots->mStyle;
}

nsresult
nsStyledElementNotElementCSSInlineStyle::ReparseStyleAttribute(bool aForceInDataDoc)
{
  if (!MayHaveStyle()) {
    return NS_OK;
  }
  const nsAttrValue* oldVal = mAttrsAndChildren.GetAttr(nsGkAtoms::style);
  
  if (oldVal && oldVal->Type() != nsAttrValue::eCSSStyleRule) {
    nsAttrValue attrValue;
    nsAutoString stringValue;
    oldVal->ToString(stringValue);
    ParseStyleAttribute(stringValue, attrValue, aForceInDataDoc);
    // Don't bother going through SetInlineStyleRule, we don't want to fire off
    // mutation events or document notifications anyway
    nsresult rv = mAttrsAndChildren.SetAndTakeAttr(nsGkAtoms::style, attrValue);
    NS_ENSURE_SUCCESS(rv, rv);
  }
  
  return NS_OK;
}

void
nsStyledElementNotElementCSSInlineStyle::ParseStyleAttribute(const nsAString& aValue,
                                                             nsAttrValue& aResult,
                                                             bool aForceInDataDoc)
{
  nsIDocument* doc = OwnerDoc();

  if (aForceInDataDoc ||
      !doc->IsLoadedAsData() ||
      doc->IsStaticDocument()) {
    bool isCSS = true; // assume CSS until proven otherwise

    if (!IsInNativeAnonymousSubtree()) {  // native anonymous content
                                          // always assumes CSS
      nsAutoString styleType;
      doc->GetHeaderData(nsGkAtoms::headerContentStyleType, styleType);
      if (!styleType.IsEmpty()) {
        static const char textCssStr[] = "text/css";
        isCSS = (styleType.EqualsIgnoreCase(textCssStr, sizeof(textCssStr) - 1));
      }
    }

    if (isCSS) {
      css::Loader* cssLoader = doc->CSSLoader();
      nsCSSParser cssParser(cssLoader);

      nsCOMPtr<nsIURI> baseURI = GetBaseURI();

      nsRefPtr<css::StyleRule> rule;
      cssParser.ParseStyleAttribute(aValue, doc->GetDocumentURI(),
                                    baseURI,
                                    NodePrincipal(),
                                    getter_AddRefs(rule));
      if (rule) {
        aResult.SetTo(rule, &aValue);
        return;
      }
    }
  }

  aResult.SetTo(aValue);
}