gecko/widget/src/cocoa/nsLookAndFeel.mm

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/* ***** 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 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):
 *   Josh Aas <josh@mozilla.com>
 *
 * 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
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 * 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 "nsLookAndFeel.h"
#include "nsObjCExceptions.h"
#include "nsIInternetConfigService.h"
#include "nsIServiceManager.h"

#import <Carbon/Carbon.h>

nsLookAndFeel::nsLookAndFeel() : nsXPLookAndFeel()
{
}

nsLookAndFeel::~nsLookAndFeel()
{
}

nsresult nsLookAndFeel::NativeGetColor(const nsColorID aID, nscolor &aColor)
{
  nsresult res = NS_OK;
  
  switch (aID) {
    case eColor_WindowBackground:
    {
      nsCOMPtr<nsIInternetConfigService> icService_wb (do_GetService(NS_INTERNETCONFIGSERVICE_CONTRACTID));
      if (icService_wb) {
        res = icService_wb->GetColor(nsIInternetConfigService::eICColor_WebBackgroundColour, &aColor);
        if (NS_SUCCEEDED(res))
          return res;
      }
      
      aColor = NS_RGB(0xff,0xff,0xff); // default to white if we didn't find it in internet config
      res = NS_OK;
    }
      break;
    case eColor_WindowForeground:
      aColor = NS_RGB(0x00,0x00,0x00);        
      break;
    case eColor_WidgetBackground:
      aColor = NS_RGB(0xdd,0xdd,0xdd);
      break;
    case eColor_WidgetForeground:
      aColor = NS_RGB(0x00,0x00,0x00);        
      break;
    case eColor_WidgetSelectBackground:
      aColor = NS_RGB(0x80,0x80,0x80);
      break;
    case eColor_WidgetSelectForeground:
      aColor = NS_RGB(0x00,0x00,0x80);
      break;
    case eColor_Widget3DHighlight:
      aColor = NS_RGB(0xa0,0xa0,0xa0);
      break;
    case eColor_Widget3DShadow:
      aColor = NS_RGB(0x40,0x40,0x40);
      break;
    case eColor_TextBackground:
      aColor = NS_RGB(0xff,0xff,0xff);
      break;
    case eColor_TextForeground: 
    {
      nsCOMPtr<nsIInternetConfigService> icService_tf (do_GetService(NS_INTERNETCONFIGSERVICE_CONTRACTID));
      if (icService_tf) {
        res = icService_tf->GetColor(nsIInternetConfigService::eICColor_WebTextColor, &aColor);
        if (NS_SUCCEEDED(res))
          return res;
      }
      aColor = NS_RGB(0x00,0x00,0x00);
      res = NS_OK;
    }
      break;
    case eColor_TextSelectBackground:
      res = GetMacBrushColor(kThemeBrushPrimaryHighlightColor, aColor, NS_RGB(0x00,0x00,0x00));
      break;
    case eColor_highlight: // CSS2 color
      res = GetMacBrushColor(kThemeBrushAlternatePrimaryHighlightColor, aColor, NS_RGB(0x33,0x6F,0xCB));
      break;
    case eColor__moz_menuhover:
      res = GetMacAccentColor(eColorOffset_mac_accentregularshadow, aColor, NS_RGB(0x33,0x6F,0xCB));
      break;      
    case eColor_TextSelectForeground:
      GetColor(eColor_TextSelectBackground, aColor);
      if (aColor == 0x000000)
        aColor = NS_RGB(0xff,0xff,0xff);
      else
        aColor = NS_DONT_CHANGE_COLOR;
      break;
    case eColor_highlighttext:  // CSS2 color
    case eColor__moz_menuhovertext:
      res = GetMacTextColor(kThemeTextColorMenuItemSelected, aColor, NS_RGB(0xFF,0xFF,0xFF));
      break;
    case eColor_IMESelectedRawTextBackground:
    case eColor_IMESelectedConvertedTextBackground:
    case eColor_IMERawInputBackground:
    case eColor_IMEConvertedTextBackground:
      aColor = NS_TRANSPARENT;
      break;
    case eColor_IMESelectedRawTextForeground:
    case eColor_IMESelectedConvertedTextForeground:
    case eColor_IMERawInputForeground:
    case eColor_IMEConvertedTextForeground:
      aColor = NS_SAME_AS_FOREGROUND_COLOR;
      break;
    case eColor_IMERawInputUnderline:
    case eColor_IMEConvertedTextUnderline:
      aColor = NS_40PERCENT_FOREGROUND_COLOR;
      break;
    case eColor_IMESelectedRawTextUnderline:
    case eColor_IMESelectedConvertedTextUnderline:
      aColor = NS_SAME_AS_FOREGROUND_COLOR;
      break;
      
      //
      // css2 system colors http://www.w3.org/TR/REC-CSS2/ui.html#system-colors
      //
      // It's really hard to effectively map these to the Appearance Manager properly,
      // since they are modeled word for word after the win32 system colors and don't have any 
      // real counterparts in the Mac world. I'm sure we'll be tweaking these for 
      // years to come. 
      //
      // Thanks to mpt26@student.canterbury.ac.nz for the hardcoded values that form the defaults
      //  if querying the Appearance Manager fails ;)
      //
      
    case eColor_buttontext:
    case eColor__moz_buttonhovertext:
      res = GetMacTextColor(kThemeTextColorPushButtonActive, aColor, NS_RGB(0x00,0x00,0x00));
      break;
    case eColor_captiontext:
      res = GetMacTextColor(kThemeTextColorWindowHeaderActive, aColor, NS_RGB(0x00,0x00,0x00));
      break;
    case eColor_menutext:
      res = GetMacTextColor(kThemeTextColorMenuItemActive, aColor, NS_RGB(0x00,0x00,0x00));
      break;
    case eColor_infotext:
      res = GetMacTextColor(kThemeTextColorNotification, aColor, NS_RGB(0x00,0x00,0x00));
      break;    
    case eColor_windowtext:
      res = GetMacTextColor(kThemeTextColorDialogActive, aColor, NS_RGB(0x00,0x00,0x00));
      break;
    case eColor_activecaption:
      //no way to fetch this colour. HARDCODING to Platinum
      //active titlebar etc is #CCCCCC
      aColor = NS_RGB(0xCC,0xCC,0xCC);
      break;
    case eColor_activeborder:
      // Aqua has no border
      res = GetMacBrushColor(kThemeBrushBlack, aColor, NS_RGB(0x00,0x00,0x00));
      break;
     case eColor_appworkspace:
      // NOTE: this is an MDI color and does not exist on Mac OS X.
      // Use the closest match, which will likely be white.
      res = GetMacBrushColor(kThemeBrushDocumentWindowBackground, aColor, NS_RGB(0x63,0x63,0xCE));
      break;   
    case eColor_background:
      // NOTE: chances are good this is a pattern, not a pure color. What do we do?
      //incidentally, this is supposed to be the colour of the desktop, though how anyone
      //is supposed to guess that from the name?
      aColor = NS_RGB(0x63,0x63,0xCE);
      break;
    case eColor_buttonface:
    case eColor__moz_buttonhoverface:
      res = GetMacBrushColor(kThemeBrushButtonFaceActive, aColor, NS_RGB(0xDD,0xDD,0xDD));
      break;
    case eColor_buttonhighlight:
      //lighter of 2 possible highlight colours available
      res = GetMacBrushColor(kThemeBrushButtonActiveLightHighlight, aColor, NS_RGB(0xFF,0xFF,0xFF));
      break;
    case eColor_buttonshadow:
      //darker of 2 possible shadow colours available
      res = GetMacBrushColor(kThemeBrushButtonActiveDarkShadow, aColor, NS_RGB(0x77,0x77,0x77));
      break;
    case eColor_graytext:
      res = GetMacTextColor(kThemeTextColorDialogInactive, aColor, NS_RGB(0x77,0x77,0x77));
      break;
    case eColor_inactiveborder:
      //ScrollBar DelimiterInactive looks like an odd constant to use, but gives the right colour in most themes, 
      //also if you look at where this colour is *actually* used, it is pretty much what we want
      res = GetMacBrushColor(kThemeBrushScrollBarDelimiterInactive, aColor, NS_RGB(0x55,0x55,0x55));
      break;
    case eColor_inactivecaption:
      //best guess. Usually right in most themes I think
      res = GetMacBrushColor(kThemeBrushDialogBackgroundInactive, aColor, NS_RGB(0xDD,0xDD,0xDD));
      break;
    case eColor_inactivecaptiontext:
      res = GetMacTextColor(kThemeTextColorWindowHeaderInactive, aColor, NS_RGB(0x77,0x77,0x77));
      break;
    case eColor_scrollbar:
      //this is the scrollbar trough. HARDCODING no way to get this colour
      //res = GetMacBrushColor(??, aColor, NS_RGB(0xAA,0xAA,0xAA));
      aColor = NS_RGB(0xAA,0xAA,0xAA);
      break;
    case eColor_threeddarkshadow:
      res = GetMacBrushColor(kThemeBrushButtonActiveDarkShadow, aColor, NS_RGB(0x77,0x77,0x77));
      break;
    case eColor_threedshadow:
      res = GetMacBrushColor(kThemeBrushButtonActiveLightShadow, aColor, NS_RGB(0x99,0x99,0x99));
      break;
    case eColor_threedface:
      res = GetMacBrushColor(kThemeBrushButtonFaceActive, aColor, NS_RGB(0xDD,0xDD,0xDD));
      break;
    case eColor_threedhighlight:
      res = GetMacBrushColor(kThemeBrushButtonActiveLightHighlight, aColor, NS_RGB(0xFF,0xFF,0xFF));
      break;
    case eColor_threedlightshadow:
      //the description in the CSS2 spec says this is on the side facing the lightsource,
      //so its not a shadow in Mac OS terms, its the darker of the highlights 
      res = GetMacBrushColor(kThemeBrushButtonActiveDarkHighlight, aColor, NS_RGB(0xDD,0xDD,0xDD));
      break;
    case eColor_menu:
      //best guess. Menus have similar background to dialogs in most themes
      res = GetMacBrushColor(kThemeBrushDialogBackgroundActive, aColor, NS_RGB(0xDD,0xDD,0xDD));
      break;
    case eColor_infobackground:
      aColor = NS_RGB(0xFF,0xFF,0xC7);
      break;
    case eColor_windowframe:
      //no way to fetch this colour. HARDCODING to Platinum
      //res = GetMacBrushColor(??, aColor, NS_RGB(0xCC,0xCC,0xCC));
      aColor = NS_RGB(0xCC,0xCC,0xCC);
      break;
    case eColor_window:
      res = GetMacBrushColor(kThemeBrushDocumentWindowBackground, aColor, NS_RGB(0xFF,0xFF,0xFF));        
      break;
    case eColor__moz_field:
      aColor = NS_RGB(0xff,0xff,0xff);
      break;
    case eColor__moz_fieldtext:
      // XXX There may be a better color for this, but I'm making it
      // the same as WindowText since that's what's currently used where
      // I will use -moz-FieldText.
      res = GetMacTextColor(kThemeTextColorDialogActive, aColor, NS_RGB(0x00,0x00,0x00));
      break;
    case eColor__moz_dialog:
      // XXX There may be a better color for this, but I'm making it
      // the same as ThreeDFace since that's what's currently used where
      // I will use -moz-Dialog:
      res = GetMacBrushColor(kThemeBrushButtonFaceActive, aColor, NS_RGB(0xDD,0xDD,0xDD));
      break;
    case eColor__moz_dialogtext:
    case eColor__moz_cellhighlighttext:
    case eColor__moz_html_cellhighlighttext:
      // XXX There may be a better color for this, but I'm making it
      // the same as WindowText since that's what's currently used where
      // I will use -moz-DialogText.
      res = GetMacTextColor(kThemeTextColorDialogActive, aColor, NS_RGB(0x00,0x00,0x00));
      break;
    case eColor__moz_dragtargetzone:
      //default to lavender if not available
      res = GetMacBrushColor(kThemeBrushDragHilite, aColor, NS_RGB(0x63,0x63,0xCE));
      break;
    case eColor__moz_mac_focusring:
      //default to lavender if not available
      res = GetMacBrushColor(kThemeBrushFocusHighlight, aColor, NS_RGB(0x63,0x63,0xCE));
      break;
    case eColor__moz_mac_menushadow:
      res = GetMacBrushColor(kThemeBrushBevelActiveDark, aColor, NS_RGB(0x88,0x88,0x88));
      break;          
    case eColor__moz_mac_menutextdisable:
      res = GetMacTextColor(kThemeTextColorMenuItemDisabled, aColor, NS_RGB(0x99,0x99,0x99));
      break;      
    case eColor__moz_mac_menutextselect:
      res = GetMacTextColor(kThemeTextColorMenuItemSelected, aColor, NS_RGB(0xFF,0xFF,0xFF));
      break;      
    case eColor__moz_mac_accentlightesthighlight:
      //get this colour by querying variation table, ows. default to Platinum/Lavendar
      res = GetMacAccentColor(eColorOffset_mac_accentlightesthighlight, aColor, NS_RGB(0xEE,0xEE,0xEE));
      break;    
    case eColor__moz_mac_accentregularhighlight:
      //get this colour by querying variation table, ows. default to Aqua normal hilight color
      res = GetMacAccentColor(eColorOffset_mac_accentregularhighlight, aColor, NS_RGB(0xB5,0xD5,0xFF));
      break;        
    case eColor__moz_mac_accentface:
      //get this colour by querying variation table, ows. default to Platinum/Lavendar
      res = GetMacAccentColor(eColorOffset_mac_accentface, aColor, NS_RGB(0x99,0x99,0xFF));
      break;            
    case eColor__moz_mac_accentlightshadow:
      //get this colour by querying variation table, ows. default to Platinum/Lavendar
      res = GetMacAccentColor(eColorOffset_mac_accentlightshadow, aColor, NS_RGB(0x66,0x66,0xCC));
      break; 
    case eColor__moz_mac_menuselect:
    case eColor__moz_mac_accentregularshadow:
      //get this colour by querying variation table, ows. default to Aqua's normal menu select color
      res = GetMacAccentColor(eColorOffset_mac_accentregularshadow, aColor, NS_RGB(0x33,0x6F,0xCB));
      break;
    case eColor__moz_mac_accentdarkshadow:
      //get this colour by querying variation table, ows. default to Platinum/Lavendar
      res = GetMacAccentColor(eColorOffset_mac_accentdarkshadow, aColor, NS_RGB(0x00,0x00,0x88));
      break;
    case eColor__moz_mac_accentdarkestshadow:
      //get this colour by querying variation table, ows. default to Platinum/Lavendar
      res = GetMacAccentColor(eColorOffset_mac_accentdarkestshadow, aColor, NS_RGB(0x00,0x00,0x55));
      break;
    case eColor__moz_buttondefault:
      res = GetMacBrushColor(kThemeBrushButtonActiveDarkShadow, aColor, NS_RGB(0x77,0x77,0x77));
      break;
    case eColor__moz_mac_alternateprimaryhighlight:
      // For proper styling of lists when active
      nscolor fallbackColor;
      GetMacBrushColor(kThemeBrushPrimaryHighlightColor, fallbackColor, NS_RGB(0x00,0x00,0x00));
      res = GetMacBrushColor(kThemeBrushAlternatePrimaryHighlightColor, aColor, fallbackColor);
      break;
    case eColor__moz_cellhighlight:
    case eColor__moz_html_cellhighlight:
    case eColor__moz_mac_secondaryhighlight:
      // For inactive list selection
      res = GetMacBrushColor(kThemeBrushSecondaryHighlightColor, aColor, NS_RGB(0x00,0x00,0x00));
      break;
    case eColor__moz_eventreerow:
      // Background color of even list rows. Note that Apple's row index is different from ours.
      res = GetMacBrushColor(kThemeBrushListViewOddRowBackground, aColor, NS_RGB(0xFF,0xFF,0xFF));
      break;
    case eColor__moz_oddtreerow:
      // Background color of odd list rows.
      res = GetMacBrushColor(kThemeBrushListViewEvenRowBackground, aColor, NS_RGB(0xF0,0xF0,0xF0));
      break;
    case eColor__moz_nativehyperlinktext:
      // There appears to be no available system defined color. HARDCODING to the appropriate color.
      aColor = NS_RGB(0x14,0x4F,0xAE);
      break;
    default:
      NS_WARNING("Someone asked nsILookAndFeel for a color I don't know about");
      aColor = NS_RGB(0xff,0xff,0xff);
      res = NS_ERROR_FAILURE;
      break;
    }
  
  return res;
}

NS_IMETHODIMP nsLookAndFeel::GetMacBrushColor(const PRInt32 aBrushType, nscolor & aColor,
                                              const nscolor & aDefaultColor)
{
  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;

  OSStatus err = noErr;
  RGBColor macColor;

  err = ::GetThemeBrushAsColor(aBrushType, 32, true, &macColor);
  if (err == noErr) 
    aColor =  NS_RGB(macColor.red>>8, macColor.green>>8, macColor.blue>>8);
  else
    aColor = aDefaultColor;

  return NS_OK;

  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
}

NS_IMETHODIMP nsLookAndFeel::GetMacTextColor(const PRInt32 aTextType, nscolor & aColor,
                                             const nscolor & aDefaultColor)
{
  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;

  OSStatus err = noErr;
  RGBColor macColor;

  err = ::GetThemeTextColor(aTextType, 32, true, &macColor);
  if (err == noErr) 
    aColor =  NS_RGB(macColor.red>>8, macColor.green>>8, macColor.blue>>8);
  else
    aColor = aDefaultColor;

  return NS_OK;

  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
}

NS_IMETHODIMP nsLookAndFeel::GetMacAccentColor(const nsMacAccentColorOffset aAccent, 
                                               nscolor & aColor,
                                               const nscolor & aDefaultColor)
{
  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;

  nsresult res = NS_OK;
  OSStatus err = noErr;
  ColorTable colourTable;
  CTabPtr ctPointer = &colourTable;
  CTabHandle ctHandle = &ctPointer;
  CTabHandle *colors = &ctHandle;
  RGBColor *macColor;    
  
  err = ::GetThemeAccentColors(colors);
  if (err == themeHasNoAccentsErr) {
    //fine, theme doesn't support accents, use default
    res = NS_OK;
    aColor = aDefaultColor;
  } else if (err != noErr || ! colors) {
    res = NS_ERROR_FAILURE;
    aColor = aDefaultColor;
  } else {
    if ((**colors)->ctSize == 
        (eColorOffset_mac_accentdarkestshadow - eColorOffset_mac_accentlightesthighlight +1)) {
      //if the size is 7 then its likely to be a standard Platinum variation, so lets use it
      macColor = &((**colors)->ctTable[aAccent].rgb);
      aColor = NS_RGB(macColor->red>>8, macColor->green>>8, macColor->blue>>8);
      res = NS_OK;    
    } else if ((**colors)->ctSize == -1) {
      //this is probably the high contrast Black & White Platinum variation
      //so lets be high contrast
      res = NS_OK;
      if (aAccent <= eColorOffset_mac_accentface) {
        aColor = NS_RGB(0xFF,0xFF,0xFF);
      } else {
        aColor = NS_RGB(0x00,0x00,0x00);
      }
      //else if ( ?? )  // add aqua support here?
    } else {
      //some other size we've never heard of, no idea what to do with it
      res = NS_ERROR_FAILURE;
      aColor = aDefaultColor;
    }
  }

  return res;

  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
}

NS_IMETHODIMP nsLookAndFeel::GetMetric(const nsMetricID aID, PRInt32 & aMetric)
{
  NS_OBJC_BEGIN_TRY_ABORT_BLOCK_NSRESULT;

  nsresult res = nsXPLookAndFeel::GetMetric(aID, aMetric);
  if (NS_SUCCEEDED(res))
    return res;
  res = NS_OK;
  
  switch (aID) {
    case eMetric_WindowTitleHeight:
      aMetric = 0;
      break;
    case eMetric_WindowBorderWidth:
      aMetric = 4;
      break;
    case eMetric_WindowBorderHeight:
      aMetric = 4;
      break;
    case eMetric_Widget3DBorder:
      aMetric = 4;
      break;
    case eMetric_TextFieldHeight:
      aMetric = 16;
      break;
    case eMetric_TextFieldBorder:
      aMetric = 2;
      break;
    case eMetric_ButtonHorizontalInsidePaddingNavQuirks:
      aMetric = 20;
      break;
    case eMetric_ButtonHorizontalInsidePaddingOffsetNavQuirks:
      aMetric = 0;
      break;
    case eMetric_CheckboxSize:
      aMetric = 14;
      break;
    case eMetric_RadioboxSize:
      aMetric = 14;
      break;
    case eMetric_TextHorizontalInsideMinimumPadding:
      aMetric = 4;
      break;
    case eMetric_TextVerticalInsidePadding:
      aMetric = 4;
      break;
    case eMetric_TextShouldUseVerticalInsidePadding:
      aMetric = 1;
      break;
    case eMetric_TextShouldUseHorizontalInsideMinimumPadding:
      aMetric = 1;
      break;
    case eMetric_ListShouldUseHorizontalInsideMinimumPadding:
      aMetric = 0;
      break;
    case eMetric_ListHorizontalInsideMinimumPadding:
      aMetric = 4;
      break;
    case eMetric_ListShouldUseVerticalInsidePadding:
      aMetric = 1;
      break;
    case eMetric_ListVerticalInsidePadding:
      aMetric = 3;
      break;
    case eMetric_CaretBlinkTime:
      aMetric = ::GetCaretTime() * 1000 / 60;
      break;
    case eMetric_CaretWidth:
      aMetric = 1;
      break;
    case eMetric_ShowCaretDuringSelection:
      aMetric = 0;
      break;
    case eMetric_SelectTextfieldsOnKeyFocus:
      // Select textfield content when focused by kbd
      // used by nsEventStateManager::sTextfieldSelectModel
      aMetric = 1;
      break;
    case eMetric_SubmenuDelay:
      aMetric = 200;
      break;
    case eMetric_MenusCanOverlapOSBar:
      // xul popups are not allowed to overlap the menubar.
      aMetric = 0;
      break;
    case eMetric_SkipNavigatingDisabledMenuItem:
      aMetric = 1;
      break;
    case eMetric_DragFullWindow:
      aMetric = 1;
      break;        
    case eMetric_DragThresholdX:
    case eMetric_DragThresholdY:
      aMetric = 4;
      break;
    case eMetric_ScrollArrowStyle:
      ThemeScrollBarArrowStyle arrowStyle;
      ::GetThemeScrollBarArrowStyle ( &arrowStyle );
      switch (arrowStyle) {
        case kThemeScrollBarArrowsSingle:
          aMetric = eMetric_ScrollArrowStyleSingle;
          break;
        // These constants aren't selectable in System Preferences like the other two (don't know why) 
        // `defaults write -g AppleScrollBarVariant DoubleBoth` to enable it.
        case kThemeScrollBarArrowsBoth:
          aMetric = eMetric_ScrollArrowStyleBothAtEachEnd;
          break;
        // `defaults write -g AppleScrollBarVariant DoubleMin` to enable it.
        case kThemeScrollBarArrowsUpperLeft:
          aMetric = eMetric_ScrollArrowStyleBothAtTop;
          break;
        default:
          NS_WARNING("Not handling all possible ThemeScrollBarArrowStyle values");
          // fall through so we default to BothAtBottom
        case kThemeScrollBarArrowsLowerRight:
          aMetric = eMetric_ScrollArrowStyleBothAtBottom;
      }
        break;
    case eMetric_ScrollSliderStyle:
      ThemeScrollBarThumbStyle thumbStyle;
      ::GetThemeScrollBarThumbStyle ( &thumbStyle );
      switch (thumbStyle) {
        case kThemeScrollBarThumbNormal:
          aMetric = eMetric_ScrollThumbStyleNormal;
          break;
        default:
          NS_WARNING("Not handling all possible ThemeScrollBarThumbStyle values");
          // fall through so we default to Proportional
        case kThemeScrollBarThumbProportional:
          aMetric = eMetric_ScrollThumbStyleProportional;
      }
        break;
    case eMetric_TreeOpenDelay:
      aMetric = 1000;
      break;
    case eMetric_TreeCloseDelay:
      aMetric = 1000;
      break;
    case eMetric_TreeLazyScrollDelay:
      aMetric = 150;
      break;
    case eMetric_TreeScrollDelay:
      aMetric = 100;
      break;
    case eMetric_TreeScrollLinesMax:
      aMetric = 3;
      break;
    case eMetric_DWMCompositor:
    case eMetric_WindowsClassic:
    case eMetric_WindowsDefaultTheme:
      aMetric = 0;
      res = NS_ERROR_NOT_IMPLEMENTED;
      break;
    case eMetric_TabFocusModel:
    {
      // we should probably cache this
      CFPropertyListRef fullKeyboardAccessProperty;
      fullKeyboardAccessProperty = ::CFPreferencesCopyValue(CFSTR("AppleKeyboardUIMode"),
                                                            kCFPreferencesAnyApplication,
                                                            kCFPreferencesCurrentUser,
                                                            kCFPreferencesAnyHost);
      aMetric = 1;    // default to just textboxes
      if (fullKeyboardAccessProperty) {
        PRInt32 fullKeyboardAccessPrefVal;
        if (::CFNumberGetValue((CFNumberRef) fullKeyboardAccessProperty, kCFNumberIntType, &fullKeyboardAccessPrefVal)) {
          // the second bit means  "Full keyboard access" is on
          if (fullKeyboardAccessPrefVal & (1 << 1))
            aMetric = 7; // everything that can be focused
        }
        ::CFRelease(fullKeyboardAccessProperty);
      }
    }
      break;
    case eMetric_ScrollToClick:
    {
      CFPropertyListRef scrollToClickProperty =
        ::CFPreferencesCopyValue(CFSTR("AppleScrollerPagingBehavior"),
                                 kCFPreferencesAnyApplication,
                                 kCFPreferencesCurrentUser,
                                 kCFPreferencesAnyHost);
      aMetric = 0;
      if (scrollToClickProperty) {
        aMetric = (PRInt32)::CFBooleanGetValue((CFBooleanRef)scrollToClickProperty);
        ::CFRelease(scrollToClickProperty);
      }
    }
      break;
    case eMetric_IMERawInputUnderlineStyle:
    case eMetric_IMEConvertedTextUnderlineStyle:
    case eMetric_IMESelectedRawTextUnderlineStyle:
    case eMetric_IMESelectedConvertedTextUnderline:
      aMetric = NS_UNDERLINE_STYLE_SOLID;
      break;
    default:
      aMetric = 0;
      res = NS_ERROR_FAILURE;
  }
  return res;

  NS_OBJC_END_TRY_ABORT_BLOCK_NSRESULT;
}

NS_IMETHODIMP nsLookAndFeel::GetMetric(const nsMetricFloatID aID, float & aMetric)
{
  nsresult res = nsXPLookAndFeel::GetMetric(aID, aMetric);
  if (NS_SUCCEEDED(res))
    return res;
  res = NS_OK;
  
  switch (aID) {
    case eMetricFloat_TextFieldVerticalInsidePadding:
      aMetric = 0.25f;
      break;
    case eMetricFloat_TextFieldHorizontalInsidePadding:
      aMetric = 0.95f;
      break;
    case eMetricFloat_TextAreaVerticalInsidePadding:
      aMetric = 0.40f;
      break;
    case eMetricFloat_TextAreaHorizontalInsidePadding:
      aMetric = 0.40f;
      break;
    case eMetricFloat_ListVerticalInsidePadding:
      aMetric = 0.08f;
      break;
    case eMetricFloat_ListHorizontalInsidePadding:
      aMetric = 0.40f;
      break;
    case eMetricFloat_ButtonVerticalInsidePadding:
      aMetric = 0.5f;
      break;
    case eMetricFloat_ButtonHorizontalInsidePadding:
      aMetric = 0.5f;
      break;
    case eMetricFloat_IMEUnderlineRelativeSize:
      aMetric = 2.0f;
      break;
    default:
      aMetric = -1.0;
      res = NS_ERROR_FAILURE;
  }

  return res;
}