editor/libeditor/base/ChangeCSSInlineStyleTxn.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* ***** BEGIN LICENSE BLOCK *****
   3  * Version: MPL 1.1/GPL 2.0/LGPL 2.1
   4  *
   5  * The contents of this file are subject to the Mozilla Public License Version
   6  * 1.1 (the "License"); you may not use this file except in compliance with
   7  * the License. You may obtain a copy of the License at
   8  * http://www.mozilla.org/MPL/
   9  *
  10  * Software distributed under the License is distributed on an "AS IS" basis,
  11  * WITHOUT WARRANTY OF ANY KIND, either express or implied. See the License
  12  * for the specific language governing rights and limitations under the
  13  * License.
  14  *
  15  * The Original Code is mozilla.org code.
  16  *
  17  * The Initial Developer of the Original Code is
  18  * Netscape Communications Corporation.
  19  * Portions created by the Initial Developer are Copyright (C) 1998
  20  * the Initial Developer. All Rights Reserved.
  21  *
  22  * Contributor(s):
  23  *   Original Author: Daniel Glazman <glazman@netscape.com>
  24  *
  25  * Alternatively, the contents of this file may be used under the terms of
  26  * either of the GNU General Public License Version 2 or later (the "GPL"),
  27  * or the GNU Lesser General Public License Version 2.1 or later (the "LGPL"),
  28  * in which case the provisions of the GPL or the LGPL are applicable instead
  29  * of those above. If you wish to allow use of your version of this file only
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  32  * decision by deleting the provisions above and replace them with the notice
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  34  * the provisions above, a recipient may use your version of this file under
  35  * the terms of any one of the MPL, the GPL or the LGPL.
  36  *
  37  * ***** END LICENSE BLOCK ***** */
  38
  39 #include "ChangeCSSInlineStyleTxn.h"
  40 #include "nsIDOMElement.h"
  41 #include "nsIDOMCSSStyleDeclaration.h"
  42 #include "nsIDOMElementCSSInlineStyle.h"
  43 #include "nsReadableUtils.h"
  44 #include "nsUnicharUtils.h"
  45 #include "nsCRT.h"
  46 #include "nsIAtom.h"
  47 #include "nsGkAtoms.h"
  48
  49 #define kNullCh (PRUnichar('\0'))
  50
  51 NS_IMPL_CYCLE_COLLECTION_CLASS(ChangeCSSInlineStyleTxn)
  52
  53 NS_IMPL_CYCLE_COLLECTION_UNLINK_BEGIN_INHERITED(ChangeCSSInlineStyleTxn,
  54                                                 EditTxn)
  55   NS_IMPL_CYCLE_COLLECTION_UNLINK_NSCOMPTR(mElement)
  56 NS_IMPL_CYCLE_COLLECTION_UNLINK_END
  57
  58 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_BEGIN_INHERITED(ChangeCSSInlineStyleTxn,
  59                                                   EditTxn)
  60   NS_IMPL_CYCLE_COLLECTION_TRAVERSE_NSCOMPTR(mElement)
  61 NS_IMPL_CYCLE_COLLECTION_TRAVERSE_END
  62
  63 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ChangeCSSInlineStyleTxn)
  64 NS_INTERFACE_MAP_END_INHERITING(EditTxn)
  65
  66 // answers true if aValue is in the string list of white-space separated values aValueList
  67 // a case-sensitive search is performed if aCaseSensitive is true
  68 PRBool
  69 ChangeCSSInlineStyleTxn::ValueIncludes(const nsAString &aValueList, const nsAString &aValue, PRBool aCaseSensitive)
  70 {
  71   nsAutoString  valueList(aValueList);
  72   PRBool result = PR_FALSE;
  73
  74   valueList.Append(kNullCh);  // put an extra null at the end
  75
  76   PRUnichar *value = ToNewUnicode(aValue);
  77   PRUnichar *start = valueList.BeginWriting();
  78   PRUnichar *end   = start;
  79
  80   while (kNullCh != *start) {
  81     while ((kNullCh != *start) && nsCRT::IsAsciiSpace(*start)) {  // skip leading space
  82       start++;
  83     }
  84     end = start;
  85
  86     while ((kNullCh != *end) && (PR_FALSE == nsCRT::IsAsciiSpace(*end))) { // look for space or end
  87       end++;
  88     }
  89     *end = kNullCh; // end string here
  90
  91     if (start < end) {
  92       if (aCaseSensitive) {
  93         if (!nsCRT::strcmp(value, start)) {
  94           result = PR_TRUE;
  95           break;
  96         }
  97       }
  98       else {
  99         if (nsDependentString(value).Equals(nsDependentString(start),
 100                                             nsCaseInsensitiveStringComparator())) {
 101           result = PR_TRUE;
 102           break;
 103         }
 104       }
 105     }
 106     start = ++end;
 107   }
 108   NS_Free(value);
 109   return result;
 110 }
 111
 112 // removes the value aRemoveValue from the string list of white-space separated values aValueList
 113 void
 114 ChangeCSSInlineStyleTxn::RemoveValueFromListOfValues(nsAString & aValues, const nsAString  & aRemoveValue)
 115 {
 116   nsAutoString  classStr(aValues);  // copy to work buffer   nsAutoString  rv(aRemoveValue);
 117   nsAutoString  outString;
 118   classStr.Append(kNullCh);  // put an extra null at the end
 119
 120   PRUnichar *start = classStr.BeginWriting();
 121   PRUnichar *end   = start;
 122
 123   while (kNullCh != *start) {
 124     while ((kNullCh != *start) && nsCRT::IsAsciiSpace(*start)) {  // skip leading space
 125       start++;
 126     }
 127     end = start;
 128
 129     while ((kNullCh != *end) && (PR_FALSE == nsCRT::IsAsciiSpace(*end))) { // look for space or end
 130       end++;
 131     }
 132     *end = kNullCh; // end string here
 133
 134     if (start < end) {
 135       if (!aRemoveValue.Equals(start)) {
 136         outString.Append(start);
 137         outString.Append(PRUnichar(' '));
 138       }
 139     }
 140
 141     start = ++end;
 142   }
 143   aValues.Assign(outString);
 144 }
 145
 146 ChangeCSSInlineStyleTxn::ChangeCSSInlineStyleTxn()
 147   : EditTxn()
 148 {
 149 }
 150
 151 NS_IMETHODIMP ChangeCSSInlineStyleTxn::Init(nsIEditor      *aEditor,
 152                                             nsIDOMElement  *aElement,
 153                                             nsIAtom        *aProperty,
 154                                             const nsAString& aValue,
 155                                             PRBool aRemoveProperty)
 156 {
 157   NS_ASSERTION(aEditor && aElement, "bad arg");
 158   if (!aEditor || !aElement) { return NS_ERROR_NULL_POINTER; }
 159
 160   mEditor = aEditor;
 161   mElement = do_QueryInterface(aElement);
 162   mProperty = aProperty;
 163   NS_ADDREF(mProperty);
 164   mValue.Assign(aValue);
 165   mRemoveProperty = aRemoveProperty;
 166   mUndoAttributeWasSet = PR_FALSE;
 167   mRedoAttributeWasSet = PR_FALSE;
 168   mUndoValue.Truncate();
 169   mRedoValue.Truncate();
 170   return NS_OK;
 171 }
 172
 173 NS_IMETHODIMP ChangeCSSInlineStyleTxn::DoTransaction(void)
 174 {
 175   NS_ASSERTION(mEditor && mElement, "bad state");
 176   if (!mEditor || !mElement) { return NS_ERROR_NOT_INITIALIZED; }
 177
 178   nsCOMPtr<nsIDOMElementCSSInlineStyle> inlineStyles = do_QueryInterface(mElement);
 179   if (!inlineStyles) return NS_ERROR_NULL_POINTER;
 180
 181   nsCOMPtr<nsIDOMCSSStyleDeclaration> cssDecl;
 182   nsresult result = inlineStyles->GetStyle(getter_AddRefs(cssDecl));
 183   if (NS_FAILED(result)) return result;
 184   if (!cssDecl) return NS_ERROR_NULL_POINTER;
 185
 186   nsAutoString propertyNameString;
 187   mProperty->ToString(propertyNameString);
 188
 189   NS_NAMED_LITERAL_STRING(styleAttr, "style");
 190   result = mElement->HasAttribute(styleAttr, &mUndoAttributeWasSet);
 191   if (NS_FAILED(result)) return result;
 192
 193   nsAutoString values;
 194   result = cssDecl->GetPropertyValue(propertyNameString, values);
 195   if (NS_FAILED(result)) return result;
 196   mUndoValue.Assign(values);
 197
 198   // does this property accept more than 1 value ?
 199   // we need to know that because of bug 62682
 200   PRBool multiple = AcceptsMoreThanOneValue(mProperty);
 201
 202   if (mRemoveProperty) {
 203     nsAutoString returnString;
 204     if (multiple) {
 205       // the property can have more than one value, let's remove only
 206       // the value we have to remove and not the others
 207
 208       // the 2 lines below are a workaround because nsDOMCSSDeclaration::GetPropertyCSSValue
 209       // is not yet implemented (bug 62682)
 210       RemoveValueFromListOfValues(values, NS_LITERAL_STRING("none"));
 211       RemoveValueFromListOfValues(values, mValue);
 212       if (values.IsEmpty()) {
 213         result = cssDecl->RemoveProperty(propertyNameString, returnString);
 214         if (NS_FAILED(result)) return result;
 215       }
 216       else {
 217         nsAutoString priority;
 218         result = cssDecl->GetPropertyPriority(propertyNameString, priority);
 219         if (NS_FAILED(result)) return result;
 220         result = cssDecl->SetProperty(propertyNameString, values,
 221                                       priority);
 222         if (NS_FAILED(result)) return result;
 223       }
 224     }
 225     else {
 226       result = cssDecl->RemoveProperty(propertyNameString, returnString);
 227       if (NS_FAILED(result)) return result;
 228     }
 229   }
 230   else {
 231     nsAutoString priority;
 232     result = cssDecl->GetPropertyPriority(propertyNameString, priority);
 233     if (NS_FAILED(result)) return result;
 234     if (multiple) {
 235       // the property can have more than one value, let's add
 236       // the value we have to add to the others
 237
 238       // the line below is a workaround because nsDOMCSSDeclaration::GetPropertyCSSValue
 239       // is not yet implemented (bug 62682)
 240       AddValueToMultivalueProperty(values, mValue);
 241     }
 242     else
 243       values.Assign(mValue);
 244     result = cssDecl->SetProperty(propertyNameString, values,
 245                                   priority);
 246     if (NS_FAILED(result)) return result;
 247   }
 248
 249   // let's be sure we don't keep an empty style attribute
 250   PRUint32 length;
 251   result = cssDecl->GetLength(&length);
 252   if (NS_FAILED(result)) return result;
 253   if (!length) {
 254     result = mElement->RemoveAttribute(styleAttr);
 255     if (NS_FAILED(result)) return result;
 256   }
 257   else
 258     mRedoAttributeWasSet = PR_TRUE;
 259
 260   return cssDecl->GetPropertyValue(propertyNameString, mRedoValue);
 261 }
 262
 263 nsresult ChangeCSSInlineStyleTxn::SetStyle(PRBool aAttributeWasSet,
 264                                            nsAString & aValue)
 265 {
 266   NS_ASSERTION(mEditor && mElement, "bad state");
 267   if (!mEditor || !mElement) { return NS_ERROR_NOT_INITIALIZED; }
 268
 269   nsresult result;
 270   if (aAttributeWasSet) {
 271     // the style attribute was set and not empty, let's recreate the declaration
 272     nsAutoString propertyNameString;
 273     mProperty->ToString(propertyNameString);
 274
 275     nsCOMPtr<nsIDOMElementCSSInlineStyle> inlineStyles = do_QueryInterface(mElement);
 276     if (!inlineStyles) return NS_ERROR_NULL_POINTER;
 277     nsCOMPtr<nsIDOMCSSStyleDeclaration> cssDecl;
 278     result = inlineStyles->GetStyle(getter_AddRefs(cssDecl));
 279     if (NS_FAILED(result)) return result;
 280     if (!cssDecl) return NS_ERROR_NULL_POINTER;
 281
 282     if (aValue.IsEmpty()) {
 283       // an empty value means we have to remove the property
 284       nsAutoString returnString;
 285       result = cssDecl->RemoveProperty(propertyNameString, returnString);
 286     }
 287     else {
 288       // let's recreate the declaration as it was
 289       nsAutoString priority;
 290       result = cssDecl->GetPropertyPriority(propertyNameString, priority);
 291       if (NS_FAILED(result)) return result;
 292       result = cssDecl->SetProperty(propertyNameString, aValue, priority);
 293     }
 294   }
 295   else
 296     result = mElement->RemoveAttribute(NS_LITERAL_STRING("style"));
 297
 298   return result;
 299 }
 300
 301 NS_IMETHODIMP ChangeCSSInlineStyleTxn::UndoTransaction(void)
 302 {
 303   return SetStyle(mUndoAttributeWasSet, mUndoValue);
 304 }
 305
 306 NS_IMETHODIMP ChangeCSSInlineStyleTxn::RedoTransaction(void)
 307 {
 308   return SetStyle(mRedoAttributeWasSet, mRedoValue);
 309 }
 310
 311 NS_IMETHODIMP ChangeCSSInlineStyleTxn::GetTxnDescription(nsAString& aString)
 312 {
 313   aString.AssignLiteral("ChangeCSSInlineStyleTxn: [mRemoveProperty == ");
 314
 315   if (!mRemoveProperty)
 316     aString.AppendLiteral("false] ");
 317   else
 318     aString.AppendLiteral("true] ");
 319   nsAutoString tempString;
 320   mProperty->ToString(tempString);
 321   aString += tempString;
 322   return NS_OK;
 323 }
 324
 325 // answers true if the CSS property accepts more than one value
 326 PRBool
 327 ChangeCSSInlineStyleTxn::AcceptsMoreThanOneValue(nsIAtom *aCSSProperty)
 328 {
 329   return aCSSProperty == nsGkAtoms::text_decoration;
 330 }
 331
 332 // adds the value aNewValue to the list of white-space separated values aValues
 333 NS_IMETHODIMP
 334 ChangeCSSInlineStyleTxn::AddValueToMultivalueProperty(nsAString & aValues, const nsAString & aNewValue)
 335 {
 336   if (aValues.IsEmpty()
 337       || aValues.LowerCaseEqualsLiteral("none")) {
 338     // the list of values is empty of the value is 'none'
 339     aValues.Assign(aNewValue);
 340   }
 341   else if (!ValueIncludes(aValues, aNewValue, PR_FALSE)) {
 342     // we already have another value but not this one; add it
 343     aValues.Append(PRUnichar(' '));
 344     aValues.Append(aNewValue);
 345   }
 346   return NS_OK;
 347 }