editor/libeditor/ChangeStyleTransaction.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* This Source Code Form is subject to the terms of the Mozilla Public
   3  * License, v. 2.0. If a copy of the MPL was not distributed with this
   4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   5
   6 #include "ChangeStyleTransaction.h"
   7
   8 #include "HTMLEditUtils.h"
   9 #include "mozilla/Logging.h"
  10 #include "mozilla/ToString.h"
  11 #include "mozilla/dom/Element.h"  // for Element
  12 #include "nsAString.h"            // for nsAString::Append, etc.
  13 #include "nsCRT.h"                // for nsCRT::IsAsciiSpace
  14 #include "nsDebug.h"              // for NS_WARNING, etc.
  15 #include "nsError.h"              // for NS_ERROR_NULL_POINTER, etc.
  16 #include "nsGkAtoms.h"            // for nsGkAtoms, etc.
  17 #include "nsICSSDeclaration.h"    // for nsICSSDeclaration.
  18 #include "nsLiteralString.h"      // for NS_LITERAL_STRING, etc.
  19 #include "nsReadableUtils.h"      // for ToNewUnicode
  20 #include "nsString.h"             // for nsAutoString, nsString, etc.
  21 #include "nsStyledElement.h"      // for nsStyledElement.
  22 #include "nsUnicharUtils.h"       // for nsCaseInsensitiveStringComparator
  23
  24 namespace mozilla {
  25
  26 using namespace dom;
  27
  28 // static
  29 already_AddRefed<ChangeStyleTransaction> ChangeStyleTransaction::Create(
  30     nsStyledElement& aStyledElement, nsAtom& aProperty,
  31     const nsAString& aValue) {
  32   RefPtr<ChangeStyleTransaction> transaction =
  33       new ChangeStyleTransaction(aStyledElement, aProperty, aValue, false);
  34   return transaction.forget();
  35 }
  36
  37 // static
  38 already_AddRefed<ChangeStyleTransaction> ChangeStyleTransaction::CreateToRemove(
  39     nsStyledElement& aStyledElement, nsAtom& aProperty,
  40     const nsAString& aValue) {
  41   RefPtr<ChangeStyleTransaction> transaction =
  42       new ChangeStyleTransaction(aStyledElement, aProperty, aValue, true);
  43   return transaction.forget();
  44 }
  45
  46 ChangeStyleTransaction::ChangeStyleTransaction(nsStyledElement& aStyledElement,
  47                                                nsAtom& aProperty,
  48                                                const nsAString& aValue,
  49                                                bool aRemove)
  50     : EditTransactionBase(),
  51       mStyledElement(&aStyledElement),
  52       mProperty(&aProperty),
  53       mUndoValue(),
  54       mRedoValue(),
  55       mRemoveProperty(aRemove),
  56       mUndoAttributeWasSet(false),
  57       mRedoAttributeWasSet(false) {
  58   CopyUTF16toUTF8(aValue, mValue);
  59 }
  60
  61 std::ostream& operator<<(std::ostream& aStream,
  62                          const ChangeStyleTransaction& aTransaction) {
  63   aStream << "{ mStyledElement=" << aTransaction.mStyledElement.get();
  64   if (aTransaction.mStyledElement) {
  65     aStream << " (" << *aTransaction.mStyledElement << ")";
  66   }
  67   aStream << ", mProperty=" << nsAtomCString(aTransaction.mProperty).get()
  68           << ", mValue=\"" << aTransaction.mValue.get() << "\", mUndoValue=\""
  69           << aTransaction.mUndoValue.get()
  70           << "\", mRedoValue=" << aTransaction.mRedoValue.get()
  71           << ", mRemoveProperty="
  72           << (aTransaction.mRemoveProperty ? "true" : "false")
  73           << ", mUndoAttributeWasSet="
  74           << (aTransaction.mUndoAttributeWasSet ? "true" : "false")
  75           << ", mRedoAttributeWasSet="
  76           << (aTransaction.mRedoAttributeWasSet ? "true" : "false") << " }";
  77   return aStream;
  78 }
  79
  80 #define kNullCh ('\0')
  81
  82 NS_IMPL_CYCLE_COLLECTION_INHERITED(ChangeStyleTransaction, EditTransactionBase,
  83                                    mStyledElement)
  84
  85 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(ChangeStyleTransaction)
  86 NS_INTERFACE_MAP_END_INHERITING(EditTransactionBase)
  87
  88 NS_IMPL_ADDREF_INHERITED(ChangeStyleTransaction, EditTransactionBase)
  89 NS_IMPL_RELEASE_INHERITED(ChangeStyleTransaction, EditTransactionBase)
  90
  91 // Answers true if aValue is in the string list of white-space separated values
  92 // aValueList.
  93 bool ChangeStyleTransaction::ValueIncludes(const nsACString& aValueList,
  94                                            const nsACString& aValue) {
  95   nsAutoCString valueList(aValueList);
  96   bool result = false;
  97
  98   // put an extra null at the end
  99   valueList.Append(kNullCh);
 100
 101   char* start = valueList.BeginWriting();
 102   char* end = start;
 103
 104   while (kNullCh != *start) {
 105     while (kNullCh != *start && nsCRT::IsAsciiSpace(*start)) {
 106       // skip leading space
 107       start++;
 108     }
 109     end = start;
 110
 111     while (kNullCh != *end && !nsCRT::IsAsciiSpace(*end)) {
 112       // look for space or end
 113       end++;
 114     }
 115     // end string here
 116     *end = kNullCh;
 117
 118     if (start < end) {
 119       if (aValue.Equals(nsDependentCString(start),
 120                         nsCaseInsensitiveCStringComparator)) {
 121         result = true;
 122         break;
 123       }
 124     }
 125     start = ++end;
 126   }
 127   return result;
 128 }
 129
 130 // Removes the value aRemoveValue from the string list of white-space separated
 131 // values aValueList
 132 void ChangeStyleTransaction::RemoveValueFromListOfValues(
 133     nsACString& aValues, const nsACString& aRemoveValue) {
 134   nsAutoCString classStr(aValues);
 135   nsAutoCString outString;
 136   // put an extra null at the end
 137   classStr.Append(kNullCh);
 138
 139   char* start = classStr.BeginWriting();
 140   char* end = start;
 141
 142   while (kNullCh != *start) {
 143     while (kNullCh != *start && nsCRT::IsAsciiSpace(*start)) {
 144       // skip leading space
 145       start++;
 146     }
 147     end = start;
 148
 149     while (kNullCh != *end && !nsCRT::IsAsciiSpace(*end)) {
 150       // look for space or end
 151       end++;
 152     }
 153     // end string here
 154     *end = kNullCh;
 155
 156     if (start < end && !aRemoveValue.Equals(start)) {
 157       outString.Append(start);
 158       outString.Append(HTMLEditUtils::kSpace);
 159     }
 160
 161     start = ++end;
 162   }
 163   aValues.Assign(outString);
 164 }
 165
 166 NS_IMETHODIMP ChangeStyleTransaction::DoTransaction() {
 167   MOZ_LOG(GetLogModule(), LogLevel::Info,
 168           ("%p ChangeStyleTransaction::%s this=%s", this, __FUNCTION__,
 169            ToString(*this).c_str()));
 170
 171   if (NS_WARN_IF(!mStyledElement)) {
 172     return NS_ERROR_NOT_AVAILABLE;
 173   }
 174
 175   OwningNonNull<nsStyledElement> styledElement = *mStyledElement;
 176   nsCOMPtr<nsICSSDeclaration> cssDecl = styledElement->Style();
 177
 178   // FIXME(bug 1606994): Using atoms forces a string copy here which is not
 179   // great.
 180   nsAutoCString propertyNameString;
 181   mProperty->ToUTF8String(propertyNameString);
 182
 183   mUndoAttributeWasSet =
 184       mStyledElement->HasAttr(kNameSpaceID_None, nsGkAtoms::style);
 185
 186   nsAutoCString values;
 187   nsresult rv = cssDecl->GetPropertyValue(propertyNameString, values);
 188   if (NS_FAILED(rv)) {
 189     NS_WARNING("nsICSSDeclaration::GetPropertyPriorityValue() failed");
 190     return rv;
 191   }
 192   mUndoValue.Assign(values);
 193
 194   // Does this property accept more than one value? (bug 62682)
 195   bool multiple = AcceptsMoreThanOneValue(*mProperty);
 196
 197   if (mRemoveProperty) {
 198     nsAutoCString returnString;
 199     if (multiple) {
 200       // Let's remove only the value we have to remove and not the others
 201       RemoveValueFromListOfValues(values, "none"_ns);
 202       RemoveValueFromListOfValues(values, mValue);
 203       if (values.IsEmpty()) {
 204         ErrorResult error;
 205         cssDecl->RemoveProperty(propertyNameString, returnString, error);
 206         if (error.Failed()) {
 207           NS_WARNING("nsICSSDeclaration::RemoveProperty() failed");
 208           return error.StealNSResult();
 209         }
 210       } else {
 211         ErrorResult error;
 212         nsAutoCString priority;
 213         cssDecl->GetPropertyPriority(propertyNameString, priority);
 214         cssDecl->SetProperty(propertyNameString, values, priority, error);
 215         if (error.Failed()) {
 216           NS_WARNING("nsICSSDeclaration::SetProperty() failed");
 217           return error.StealNSResult();
 218         }
 219       }
 220     } else {
 221       ErrorResult error;
 222       cssDecl->RemoveProperty(propertyNameString, returnString, error);
 223       if (error.Failed()) {
 224         NS_WARNING("nsICSSDeclaration::RemoveProperty() failed");
 225         return error.StealNSResult();
 226       }
 227     }
 228   } else {
 229     nsAutoCString priority;
 230     cssDecl->GetPropertyPriority(propertyNameString, priority);
 231     if (multiple) {
 232       // Let's add the value we have to add to the others
 233       AddValueToMultivalueProperty(values, mValue);
 234     } else {
 235       values.Assign(mValue);
 236     }
 237     ErrorResult error;
 238     cssDecl->SetProperty(propertyNameString, values, priority, error);
 239     if (error.Failed()) {
 240       NS_WARNING("nsICSSDeclaration::SetProperty() failed");
 241       return error.StealNSResult();
 242     }
 243   }
 244
 245   // Let's be sure we don't keep an empty style attribute
 246   uint32_t length = cssDecl->Length();
 247   if (!length) {
 248     nsresult rv =
 249         styledElement->UnsetAttr(kNameSpaceID_None, nsGkAtoms::style, true);
 250     if (NS_FAILED(rv)) {
 251       NS_WARNING("Element::UnsetAttr(nsGkAtoms::style) failed");
 252       return rv;
 253     }
 254   } else {
 255     mRedoAttributeWasSet = true;
 256   }
 257
 258   rv = cssDecl->GetPropertyValue(propertyNameString, mRedoValue);
 259   NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
 260                        "nsICSSDeclaration::GetPropertyValue() failed");
 261   return rv;
 262 }
 263
 264 nsresult ChangeStyleTransaction::SetStyle(bool aAttributeWasSet,
 265                                           nsACString& aValue) {
 266   if (NS_WARN_IF(!mStyledElement)) {
 267     return NS_ERROR_NOT_AVAILABLE;
 268   }
 269
 270   if (aAttributeWasSet) {
 271     OwningNonNull<nsStyledElement> styledElement = *mStyledElement;
 272
 273     // The style attribute was not empty, let's recreate the declaration
 274     nsAutoCString propertyNameString;
 275     mProperty->ToUTF8String(propertyNameString);
 276
 277     nsCOMPtr<nsICSSDeclaration> cssDecl = styledElement->Style();
 278
 279     ErrorResult error;
 280     if (aValue.IsEmpty()) {
 281       // An empty value means we have to remove the property
 282       nsAutoCString returnString;
 283       cssDecl->RemoveProperty(propertyNameString, returnString, error);
 284       if (error.Failed()) {
 285         NS_WARNING("nsICSSDeclaration::RemoveProperty() failed");
 286         return error.StealNSResult();
 287       }
 288     }
 289     // Let's recreate the declaration as it was
 290     nsAutoCString priority;
 291     cssDecl->GetPropertyPriority(propertyNameString, priority);
 292     cssDecl->SetProperty(propertyNameString, aValue, priority, error);
 293     NS_WARNING_ASSERTION(!error.Failed(),
 294                          "nsICSSDeclaration::SetProperty() failed");
 295     return error.StealNSResult();
 296   }
 297
 298   OwningNonNull<nsStyledElement> styledElement = *mStyledElement;
 299   nsresult rv =
 300       styledElement->UnsetAttr(kNameSpaceID_None, nsGkAtoms::style, true);
 301   NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
 302                        "Element::UnsetAttr(nsGkAtoms::style) failed");
 303   return rv;
 304 }
 305
 306 NS_IMETHODIMP ChangeStyleTransaction::UndoTransaction() {
 307   MOZ_LOG(GetLogModule(), LogLevel::Info,
 308           ("%p ChangeStyleTransaction::%s this=%s", this, __FUNCTION__,
 309            ToString(*this).c_str()));
 310
 311   nsresult rv = SetStyle(mUndoAttributeWasSet, mUndoValue);
 312   NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
 313                        "ChangeStyleTransaction::SetStyle() failed");
 314   return rv;
 315 }
 316
 317 NS_IMETHODIMP ChangeStyleTransaction::RedoTransaction() {
 318   MOZ_LOG(GetLogModule(), LogLevel::Info,
 319           ("%p ChangeStyleTransaction::%s this=%s", this, __FUNCTION__,
 320            ToString(*this).c_str()));
 321
 322   nsresult rv = SetStyle(mRedoAttributeWasSet, mRedoValue);
 323   NS_WARNING_ASSERTION(NS_SUCCEEDED(rv),
 324                        "ChangeStyleTransaction::SetStyle() failed");
 325   return rv;
 326 }
 327
 328 // True if the CSS property accepts more than one value
 329 bool ChangeStyleTransaction::AcceptsMoreThanOneValue(nsAtom& aCSSProperty) {
 330   return &aCSSProperty == nsGkAtoms::text_decoration;
 331 }
 332
 333 // Adds the value aNewValue to the list of white-space separated values aValues
 334 void ChangeStyleTransaction::AddValueToMultivalueProperty(
 335     nsACString& aValues, const nsACString& aNewValue) {
 336   if (aValues.IsEmpty() || aValues.LowerCaseEqualsLiteral("none")) {
 337     aValues.Assign(aNewValue);
 338   } else if (!ValueIncludes(aValues, aNewValue)) {
 339     // We already have another value but not this one; add it
 340     aValues.Append(HTMLEditUtils::kSpace);
 341     aValues.Append(aNewValue);
 342   }
 343 }
 344
 345 }  // namespace mozilla