gecko/editor/libeditor/html/nsHTMLAbsPosition.cpp

732 lines
24 KiB
C++

/* ***** 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.org.
*
* The Initial Developer of the Original Code is
* Netscape Communications Corp.
* Portions created by the Initial Developer are Copyright (C) 2003
* the Initial Developer. All Rights Reserved.
*
* Contributor(s):
* Daniel Glazman (glazman@netscape.com) (Original author)
*
* Alternatively, the contents of this file may be used under the terms of
* either 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
* of those above. If you wish to allow use of your version of this file only
* under the terms of either the GPL or the LGPL, and not to allow others to
* use your version of this file under the terms of the MPL, indicate your
* decision by deleting the provisions above and replace them with the notice
* and other provisions required by the GPL or the LGPL. If you do not delete
* the provisions above, a recipient may use your version of this file under
* the terms of any one of the MPL, the GPL or the LGPL.
*
* ***** END LICENSE BLOCK ***** */
#include <math.h>
#include "nsHTMLEditor.h"
#include "nsIContent.h"
#include "nsIDocument.h"
#include "nsIEditor.h"
#include "nsIPresShell.h"
#include "nsISelection.h"
#include "nsTextEditUtils.h"
#include "nsEditorUtils.h"
#include "nsHTMLEditUtils.h"
#include "nsTextEditRules.h"
#include "nsIHTMLEditRules.h"
#include "nsIDOMHTMLElement.h"
#include "nsIDOMNSHTMLElement.h"
#include "nsIDOMNodeList.h"
#include "nsIDOMEventTarget.h"
#include "nsIPrefBranch.h"
#include "nsIPrefService.h"
#include "nsIServiceManager.h"
#include "nsIDOMCSSValue.h"
#include "nsIDOMCSSPrimitiveValue.h"
#include "nsIDOMRGBColor.h"
#define BLACK_BG_RGB_TRIGGER 0xd0
NS_IMETHODIMP
nsHTMLEditor::AbsolutePositionSelection(PRBool aEnabled)
{
nsAutoEditBatch beginBatching(this);
nsAutoRules beginRulesSniffing(this,
aEnabled ? kOpSetAbsolutePosition :
kOpRemoveAbsolutePosition,
nsIEditor::eNext);
// the line below does not match the code; should it be removed?
// Find out if the selection is collapsed:
nsCOMPtr<nsISelection> selection;
nsresult res = GetSelection(getter_AddRefs(selection));
if (NS_FAILED(res)) return res;
if (!selection) return NS_ERROR_NULL_POINTER;
nsTextRulesInfo ruleInfo(aEnabled ?
nsTextEditRules::kSetAbsolutePosition :
nsTextEditRules::kRemoveAbsolutePosition);
PRBool cancel, handled;
res = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
if (NS_FAILED(res) || cancel)
return res;
return mRules->DidDoAction(selection, &ruleInfo, res);
}
NS_IMETHODIMP
nsHTMLEditor::GetAbsolutelyPositionedSelectionContainer(nsIDOMElement **_retval)
{
nsCOMPtr<nsIDOMElement> element;
nsresult res = GetSelectionContainer(getter_AddRefs(element));
if (NS_FAILED(res)) return res;
nsAutoString positionStr;
nsCOMPtr<nsIDOMNode> node = do_QueryInterface(element);
nsCOMPtr<nsIDOMNode> resultNode;
do {
res = mHTMLCSSUtils->GetComputedProperty(node, nsEditProperty::cssPosition,
positionStr);
if (NS_FAILED(res)) return res;
if (positionStr.EqualsLiteral("absolute"))
resultNode = node;
else {
nsCOMPtr<nsIDOMNode> parentNode;
res = node->GetParentNode(getter_AddRefs(parentNode));
if (NS_FAILED(res)) return res;
node.swap(parentNode);
}
} while (!resultNode &&
!nsEditor::NodeIsType(node, nsEditProperty::html));
element = do_QueryInterface(resultNode );
*_retval = element;
NS_IF_ADDREF(*_retval);
return NS_OK;
}
NS_IMETHODIMP
nsHTMLEditor::GetSelectionContainerAbsolutelyPositioned(PRBool *aIsSelectionContainerAbsolutelyPositioned)
{
*aIsSelectionContainerAbsolutelyPositioned = (mAbsolutelyPositionedObject != nsnull);
return NS_OK;
}
NS_IMETHODIMP
nsHTMLEditor::GetAbsolutePositioningEnabled(PRBool * aIsEnabled)
{
*aIsEnabled = mIsAbsolutelyPositioningEnabled;
return NS_OK;
}
NS_IMETHODIMP
nsHTMLEditor::SetAbsolutePositioningEnabled(PRBool aIsEnabled)
{
mIsAbsolutelyPositioningEnabled = aIsEnabled;
return NS_OK;
}
NS_IMETHODIMP
nsHTMLEditor::RelativeChangeElementZIndex(nsIDOMElement * aElement,
PRInt32 aChange,
PRInt32 * aReturn)
{
NS_ENSURE_ARG_POINTER(aElement);
NS_ENSURE_ARG_POINTER(aReturn);
if (!aChange) // early way out, no change
return NS_OK;
PRInt32 zIndex;
nsresult res = GetElementZIndex(aElement, &zIndex);
if (NS_FAILED(res)) return res;
zIndex = PR_MAX(zIndex + aChange, 0);
SetElementZIndex(aElement, zIndex);
*aReturn = zIndex;
return NS_OK;
}
NS_IMETHODIMP
nsHTMLEditor::SetElementZIndex(nsIDOMElement * aElement,
PRInt32 aZindex)
{
NS_ENSURE_ARG_POINTER(aElement);
nsAutoString zIndexStr;
zIndexStr.AppendInt(aZindex);
mHTMLCSSUtils->SetCSSProperty(aElement,
nsEditProperty::cssZIndex,
zIndexStr,
PR_FALSE);
return NS_OK;
}
NS_IMETHODIMP
nsHTMLEditor::RelativeChangeZIndex(PRInt32 aChange)
{
nsAutoEditBatch beginBatching(this);
nsAutoRules beginRulesSniffing(this,
(aChange < 0) ? kOpDecreaseZIndex :
kOpIncreaseZIndex,
nsIEditor::eNext);
// brade: can we get rid of this comment?
// Find out if the selection is collapsed:
nsCOMPtr<nsISelection> selection;
nsresult res = GetSelection(getter_AddRefs(selection));
if (NS_FAILED(res)) return res;
if (!selection) return NS_ERROR_NULL_POINTER;
nsTextRulesInfo ruleInfo((aChange < 0) ? nsTextEditRules::kDecreaseZIndex:
nsTextEditRules::kIncreaseZIndex);
PRBool cancel, handled;
res = mRules->WillDoAction(selection, &ruleInfo, &cancel, &handled);
if (cancel || NS_FAILED(res))
return res;
return mRules->DidDoAction(selection, &ruleInfo, res);
}
NS_IMETHODIMP
nsHTMLEditor::GetElementZIndex(nsIDOMElement * aElement,
PRInt32 * aZindex)
{
nsAutoString zIndexStr;
*aZindex = 0;
nsresult res = mHTMLCSSUtils->GetSpecifiedProperty(aElement,
nsEditProperty::cssZIndex,
zIndexStr);
if (NS_FAILED(res)) return res;
if (zIndexStr.EqualsLiteral("auto")) {
// we have to look at the positioned ancestors
// cf. CSS 2 spec section 9.9.1
nsCOMPtr<nsIDOMNode> parentNode;
res = aElement->GetParentNode(getter_AddRefs(parentNode));
if (NS_FAILED(res)) return res;
nsCOMPtr<nsIDOMNode> node = parentNode;
nsAutoString positionStr;
while (node &&
zIndexStr.EqualsLiteral("auto") &&
!nsTextEditUtils::IsBody(node)) {
res = mHTMLCSSUtils->GetComputedProperty(node,
nsEditProperty::cssPosition,
positionStr);
if (NS_FAILED(res)) return res;
if (positionStr.EqualsLiteral("absolute")) {
// ah, we found one, what's its z-index ? If its z-index is auto,
// we have to continue climbing the document's tree
res = mHTMLCSSUtils->GetComputedProperty(node,
nsEditProperty::cssZIndex,
zIndexStr);
if (NS_FAILED(res)) return res;
}
res = node->GetParentNode(getter_AddRefs(parentNode));
if (NS_FAILED(res)) return res;
node = parentNode;
}
}
if (!zIndexStr.EqualsLiteral("auto")) {
PRInt32 errorCode;
*aZindex = zIndexStr.ToInteger(&errorCode);
}
return NS_OK;
}
nsresult
nsHTMLEditor::CreateGrabber(nsIDOMNode * aParentNode, nsIDOMElement ** aReturn)
{
// let's create a grabber through the element factory
nsresult res = CreateAnonymousElement(NS_LITERAL_STRING("span"),
aParentNode,
NS_LITERAL_STRING("mozGrabber"),
PR_FALSE,
aReturn);
if (!*aReturn)
return NS_ERROR_FAILURE;
// add the mouse listener so we can detect a click on a resizer
nsCOMPtr<nsIDOMEventTarget> evtTarget(do_QueryInterface(*aReturn));
evtTarget->AddEventListener(NS_LITERAL_STRING("mousedown"), mMouseListenerP, PR_FALSE);
return res;
}
NS_IMETHODIMP
nsHTMLEditor::RefreshGrabber()
{
NS_ENSURE_TRUE(mAbsolutelyPositionedObject, NS_ERROR_NULL_POINTER);
nsresult res = GetPositionAndDimensions(mAbsolutelyPositionedObject,
mPositionedObjectX,
mPositionedObjectY,
mPositionedObjectWidth,
mPositionedObjectHeight,
mPositionedObjectBorderLeft,
mPositionedObjectBorderTop,
mPositionedObjectMarginLeft,
mPositionedObjectMarginTop);
if (NS_FAILED(res)) return res;
SetAnonymousElementPosition(mPositionedObjectX+12,
mPositionedObjectY-14,
mGrabber);
return NS_OK;
}
NS_IMETHODIMP
nsHTMLEditor::HideGrabber()
{
nsresult res =
mAbsolutelyPositionedObject->RemoveAttribute(NS_LITERAL_STRING("_moz_abspos"));
if (NS_FAILED(res)) return res;
mAbsolutelyPositionedObject = nsnull;
NS_ENSURE_TRUE(mGrabber, NS_ERROR_NULL_POINTER);
// get the presshell's document observer interface.
nsCOMPtr<nsIPresShell> ps = do_QueryReferent(mPresShellWeak);
if (!ps) return NS_ERROR_NOT_INITIALIZED;
// get the root content node.
nsIDOMElement *rootElement = GetRoot();
nsCOMPtr<nsIContent> rootContent = do_QueryInterface(rootElement);
if (!rootContent) return NS_ERROR_NULL_POINTER;
DeleteRefToAnonymousNode(mGrabber, rootContent, ps);
mGrabber = nsnull;
DeleteRefToAnonymousNode(mPositioningShadow, rootContent, ps);
mPositioningShadow = nsnull;
return NS_OK;
}
NS_IMETHODIMP
nsHTMLEditor::ShowGrabberOnElement(nsIDOMElement * aElement)
{
NS_ENSURE_ARG_POINTER(aElement);
nsAutoString classValue;
nsresult res = CheckPositionedElementBGandFG(aElement, classValue);
if (NS_FAILED(res)) return res;
res = aElement->SetAttribute(NS_LITERAL_STRING("_moz_abspos"),
classValue);
if (NS_FAILED(res)) return res;
// first, let's keep track of that element...
mAbsolutelyPositionedObject = aElement;
nsIDOMElement *rootElement = GetRoot();
if (!rootElement) return NS_ERROR_NULL_POINTER;
res = CreateGrabber(rootElement, getter_AddRefs(mGrabber));
if (NS_FAILED(res)) return res;
// and set its position
return RefreshGrabber();
}
nsresult
nsHTMLEditor::StartMoving(nsIDOMElement *aHandle)
{
nsIDOMElement *rootElement = GetRoot();
if (!rootElement) return NS_ERROR_NULL_POINTER;
// now, let's create the resizing shadow
nsresult result = CreateShadow(getter_AddRefs(mPositioningShadow),
rootElement, mAbsolutelyPositionedObject);
if (NS_FAILED(result)) return result;
result = SetShadowPosition(mPositioningShadow, mAbsolutelyPositionedObject,
mPositionedObjectX, mPositionedObjectY);
if (NS_FAILED(result)) return result;
// make the shadow appear
mPositioningShadow->RemoveAttribute(NS_LITERAL_STRING("class"));
// position it
mHTMLCSSUtils->SetCSSPropertyPixels(mPositioningShadow,
NS_LITERAL_STRING("width"),
mPositionedObjectWidth);
mHTMLCSSUtils->SetCSSPropertyPixels(mPositioningShadow,
NS_LITERAL_STRING("height"),
mPositionedObjectHeight);
mIsMoving = PR_TRUE;
return result;
}
void
nsHTMLEditor::SnapToGrid(PRInt32 & newX, PRInt32 & newY)
{
if (mSnapToGridEnabled && mGridSize) {
newX = (PRInt32) floor( ((float)newX / (float)mGridSize) + 0.5f ) * mGridSize;
newY = (PRInt32) floor( ((float)newY / (float)mGridSize) + 0.5f ) * mGridSize;
}
}
nsresult
nsHTMLEditor::GrabberClicked()
{
// add a mouse move listener to the editor
nsresult res = NS_OK;
if (!mMouseMotionListenerP) {
mMouseMotionListenerP = new ResizerMouseMotionListener(this);
if (!mMouseMotionListenerP) {return NS_ERROR_NULL_POINTER;}
nsCOMPtr<nsPIDOMEventTarget> piTarget = GetPIDOMEventTarget();
NS_ENSURE_TRUE(piTarget, NS_ERROR_FAILURE);
res = piTarget->AddEventListenerByIID(mMouseMotionListenerP,
NS_GET_IID(nsIDOMMouseMotionListener));
NS_ASSERTION(NS_SUCCEEDED(res),
"failed to register mouse motion listener");
}
mGrabberClicked = PR_TRUE;
return res;
}
nsresult
nsHTMLEditor::EndMoving()
{
if (mPositioningShadow) {
nsCOMPtr<nsIPresShell> ps = do_QueryReferent(mPresShellWeak);
if (!ps) return NS_ERROR_NOT_INITIALIZED;
// get the root content node.
nsIDOMElement *rootElement = GetRoot();
nsCOMPtr<nsIContent> rootContent( do_QueryInterface(rootElement) );
if (!rootContent) return NS_ERROR_FAILURE;
DeleteRefToAnonymousNode(mPositioningShadow, rootContent, ps);
mPositioningShadow = nsnull;
}
nsCOMPtr<nsPIDOMEventTarget> piTarget = GetPIDOMEventTarget();
if (piTarget && mMouseMotionListenerP) {
#ifdef DEBUG
nsresult res =
#endif
piTarget->RemoveEventListenerByIID(mMouseMotionListenerP,
NS_GET_IID(nsIDOMMouseMotionListener));
NS_ASSERTION(NS_SUCCEEDED(res), "failed to remove mouse motion listener");
}
mMouseMotionListenerP = nsnull;
mGrabberClicked = PR_FALSE;
mIsMoving = PR_FALSE;
nsCOMPtr<nsISelection> selection;
GetSelection(getter_AddRefs(selection));
if (!selection) {
return NS_ERROR_NOT_INITIALIZED;
}
return CheckSelectionStateForAnonymousButtons(selection);
}
nsresult
nsHTMLEditor::SetFinalPosition(PRInt32 aX, PRInt32 aY)
{
nsresult res = EndMoving();
if (NS_FAILED(res)) return res;
// we have now to set the new width and height of the resized object
// we don't set the x and y position because we don't control that in
// a normal HTML layout
PRInt32 newX = mPositionedObjectX + aX - mOriginalX - (mPositionedObjectBorderLeft+mPositionedObjectMarginLeft);
PRInt32 newY = mPositionedObjectY + aY - mOriginalY - (mPositionedObjectBorderTop+mPositionedObjectMarginTop);
SnapToGrid(newX, newY);
nsAutoString x, y;
x.AppendInt(newX);
y.AppendInt(newY);
// we want one transaction only from a user's point of view
nsAutoEditBatch batchIt(this);
mHTMLCSSUtils->SetCSSPropertyPixels(mAbsolutelyPositionedObject,
nsEditProperty::cssTop,
newY,
PR_FALSE);
mHTMLCSSUtils->SetCSSPropertyPixels(mAbsolutelyPositionedObject,
nsEditProperty::cssLeft,
newX,
PR_FALSE);
// keep track of that size
mPositionedObjectX = newX;
mPositionedObjectY = newY;
return RefreshResizers();
}
void
nsHTMLEditor::AddPositioningOffet(PRInt32 & aX, PRInt32 & aY)
{
// Get the positioning offset
nsresult res;
nsCOMPtr<nsIPrefBranch> prefBranch =
do_GetService(NS_PREFSERVICE_CONTRACTID, &res);
PRInt32 positioningOffset = 0;
if (NS_SUCCEEDED(res) && prefBranch) {
res = prefBranch->GetIntPref("editor.positioning.offset", &positioningOffset);
if (NS_FAILED(res)) // paranoia
positioningOffset = 0;
}
aX += positioningOffset;
aY += positioningOffset;
}
NS_IMETHODIMP
nsHTMLEditor::AbsolutelyPositionElement(nsIDOMElement * aElement,
PRBool aEnabled)
{
NS_ENSURE_ARG_POINTER(aElement);
nsAutoString positionStr;
mHTMLCSSUtils->GetComputedProperty(aElement, nsEditProperty::cssPosition,
positionStr);
PRBool isPositioned = (positionStr.EqualsLiteral("absolute"));
// nothing to do if the element is already in the state we want
if (isPositioned == aEnabled)
return NS_OK;
nsAutoEditBatch batchIt(this);
nsresult res;
if (aEnabled) {
PRInt32 x, y;
GetElementOrigin(aElement, x, y);
mHTMLCSSUtils->SetCSSProperty(aElement,
nsEditProperty::cssPosition,
NS_LITERAL_STRING("absolute"),
PR_FALSE);
AddPositioningOffet(x, y);
SnapToGrid(x, y);
SetElementPosition(aElement, x, y);
// we may need to create a br if the positioned element is alone in its
// container
nsCOMPtr<nsIDOMNode> parentNode;
res = aElement->GetParentNode(getter_AddRefs(parentNode));
if (NS_FAILED(res)) return res;
nsCOMPtr<nsIDOMNodeList> childNodes;
res = parentNode->GetChildNodes(getter_AddRefs(childNodes));
if (NS_FAILED(res)) return res;
if (!childNodes) return NS_ERROR_NULL_POINTER;
PRUint32 childCount;
res = childNodes->GetLength(&childCount);
if (NS_FAILED(res)) return res;
if (childCount == 1) {
nsCOMPtr<nsIDOMNode> brNode;
res = CreateBR(parentNode, 0, address_of(brNode));
}
}
else {
mHTMLCSSUtils->RemoveCSSProperty(aElement,
nsEditProperty::cssPosition,
EmptyString(), PR_FALSE);
mHTMLCSSUtils->RemoveCSSProperty(aElement,
nsEditProperty::cssTop,
EmptyString(), PR_FALSE);
mHTMLCSSUtils->RemoveCSSProperty(aElement,
nsEditProperty::cssLeft,
EmptyString(), PR_FALSE);
mHTMLCSSUtils->RemoveCSSProperty(aElement,
nsEditProperty::cssZIndex,
EmptyString(), PR_FALSE);
if (!nsHTMLEditUtils::IsImage(aElement)) {
mHTMLCSSUtils->RemoveCSSProperty(aElement,
nsEditProperty::cssWidth,
EmptyString(), PR_FALSE);
mHTMLCSSUtils->RemoveCSSProperty(aElement,
nsEditProperty::cssHeight,
EmptyString(), PR_FALSE);
}
PRBool hasStyleOrIdOrClass;
res = HasStyleOrIdOrClass(aElement, &hasStyleOrIdOrClass);
if (NS_FAILED(res)) return res;
if (!hasStyleOrIdOrClass && nsHTMLEditUtils::IsDiv(aElement)) {
nsCOMPtr<nsIHTMLEditRules> htmlRules = do_QueryInterface(mRules);
if (!htmlRules) return NS_ERROR_FAILURE;
res = htmlRules->MakeSureElemStartsOrEndsOnCR(aElement);
if (NS_FAILED(res)) return res;
res = RemoveContainer(aElement);
}
}
return res;
}
NS_IMETHODIMP
nsHTMLEditor::SetSnapToGridEnabled(PRBool aEnabled)
{
mSnapToGridEnabled = aEnabled;
return NS_OK;
}
NS_IMETHODIMP
nsHTMLEditor::GetSnapToGridEnabled(PRBool * aIsEnabled)
{
*aIsEnabled = mSnapToGridEnabled;
return NS_OK;
}
NS_IMETHODIMP
nsHTMLEditor::SetGridSize(PRUint32 aSize)
{
mGridSize = aSize;
return NS_OK;
}
NS_IMETHODIMP
nsHTMLEditor::GetGridSize(PRUint32 * aSize)
{
*aSize = mGridSize;
return NS_OK;
}
// self-explanatory
NS_IMETHODIMP
nsHTMLEditor::SetElementPosition(nsIDOMElement *aElement, PRInt32 aX, PRInt32 aY)
{
nsAutoEditBatch batchIt(this);
mHTMLCSSUtils->SetCSSPropertyPixels(aElement,
nsEditProperty::cssLeft,
aX,
PR_FALSE);
mHTMLCSSUtils->SetCSSPropertyPixels(aElement,
nsEditProperty::cssTop,
aY,
PR_FALSE);
return NS_OK;
}
// self-explanatory
NS_IMETHODIMP
nsHTMLEditor::GetPositionedElement(nsIDOMElement ** aReturn)
{
*aReturn = mAbsolutelyPositionedObject;
NS_IF_ADDREF(*aReturn);
return NS_OK;
}
nsresult
nsHTMLEditor::CheckPositionedElementBGandFG(nsIDOMElement * aElement,
nsAString & aReturn)
{
// we are going to outline the positioned element and bring it to the
// front to overlap any other element intersecting with it. But
// first, let's see what's the background and foreground colors of the
// positioned element.
// if background-image computed value is 'none,
// If the background color is 'auto' and R G B values of the foreground are
// each above #d0, use a black background
// If the background color is 'auto' and at least one of R G B values of
// the foreground is below #d0, use a white background
// Otherwise don't change background/foreground
aReturn.Truncate();
nsAutoString bgImageStr;
nsresult res =
mHTMLCSSUtils->GetComputedProperty(aElement,
nsEditProperty::cssBackgroundImage,
bgImageStr);
if (NS_FAILED(res)) return res;
if (bgImageStr.EqualsLiteral("none")) {
nsAutoString bgColorStr;
res =
mHTMLCSSUtils->GetComputedProperty(aElement,
nsEditProperty::cssBackgroundColor,
bgColorStr);
if (NS_FAILED(res)) return res;
if (bgColorStr.EqualsLiteral("transparent")) {
nsCOMPtr<nsIDOMViewCSS> viewCSS;
res = mHTMLCSSUtils->GetDefaultViewCSS(aElement, getter_AddRefs(viewCSS));
if (NS_FAILED(res)) return res;
nsCOMPtr<nsIDOMCSSStyleDeclaration> cssDecl;
res = viewCSS->GetComputedStyle(aElement, EmptyString(), getter_AddRefs(cssDecl));
if (NS_FAILED(res)) return res;
// from these declarations, get the one we want and that one only
nsCOMPtr<nsIDOMCSSValue> colorCssValue;
res = cssDecl->GetPropertyCSSValue(NS_LITERAL_STRING("color"), getter_AddRefs(colorCssValue));
if (NS_FAILED(res)) return res;
PRUint16 type;
res = colorCssValue->GetCssValueType(&type);
if (NS_FAILED(res)) return res;
if (nsIDOMCSSValue::CSS_PRIMITIVE_VALUE == type) {
nsCOMPtr<nsIDOMCSSPrimitiveValue> val = do_QueryInterface(colorCssValue);
res = val->GetPrimitiveType(&type);
if (NS_FAILED(res)) return res;
if (nsIDOMCSSPrimitiveValue::CSS_RGBCOLOR == type) {
nsCOMPtr<nsIDOMRGBColor> rgbColor;
res = val->GetRGBColorValue(getter_AddRefs(rgbColor));
if (NS_FAILED(res)) return res;
nsCOMPtr<nsIDOMCSSPrimitiveValue> red, green, blue;
float r, g, b;
res = rgbColor->GetRed(getter_AddRefs(red));
if (NS_FAILED(res)) return res;
res = rgbColor->GetGreen(getter_AddRefs(green));
if (NS_FAILED(res)) return res;
res = rgbColor->GetBlue(getter_AddRefs(blue));
if (NS_FAILED(res)) return res;
res = red->GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_NUMBER, &r);
if (NS_FAILED(res)) return res;
res = green->GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_NUMBER, &g);
if (NS_FAILED(res)) return res;
res = blue->GetFloatValue(nsIDOMCSSPrimitiveValue::CSS_NUMBER, &b);
if (NS_FAILED(res)) return res;
if (r >= BLACK_BG_RGB_TRIGGER &&
g >= BLACK_BG_RGB_TRIGGER &&
b >= BLACK_BG_RGB_TRIGGER)
aReturn.AssignLiteral("black");
else
aReturn.AssignLiteral("white");
return NS_OK;
}
}
}
}
return NS_OK;
}