editor/libeditor/CSSEditUtils.h

   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 #ifndef mozilla_CSSEditUtils_h
   7 #define mozilla_CSSEditUtils_h
   8
   9 #include "mozilla/ChangeStyleTransaction.h"  // for ChangeStyleTransaction
  10 #include "nsCOMPtr.h"                        // for already_AddRefed
  11 #include "nsStringFwd.h"
  12 #include "nsTArray.h"  // for nsTArray
  13 #include "nscore.h"    // for nsAString, nsresult, nullptr
  14
  15 class nsComputedDOMStyle;
  16 class nsAtom;
  17 class nsIContent;
  18 class nsICSSDeclaration;
  19 class nsINode;
  20 class nsStaticAtom;
  21 class nsStyledElement;
  22
  23 namespace mozilla {
  24
  25 class HTMLEditor;
  26 namespace dom {
  27 class Element;
  28 }  // namespace dom
  29
  30 typedef void (*nsProcessValueFunc)(const nsAString* aInputString,
  31                                    nsAString& aOutputString,
  32                                    const char* aDefaultValueString,
  33                                    const char* aPrependString,
  34                                    const char* aAppendString);
  35
  36 class CSSEditUtils final {
  37  public:
  38   explicit CSSEditUtils(HTMLEditor* aEditor);
  39
  40   enum nsCSSEditableProperty {
  41     eCSSEditableProperty_NONE = 0,
  42     eCSSEditableProperty_background_color,
  43     eCSSEditableProperty_background_image,
  44     eCSSEditableProperty_border,
  45     eCSSEditableProperty_caption_side,
  46     eCSSEditableProperty_color,
  47     eCSSEditableProperty_float,
  48     eCSSEditableProperty_font_family,
  49     eCSSEditableProperty_font_size,
  50     eCSSEditableProperty_font_style,
  51     eCSSEditableProperty_font_weight,
  52     eCSSEditableProperty_height,
  53     eCSSEditableProperty_list_style_type,
  54     eCSSEditableProperty_margin_left,
  55     eCSSEditableProperty_margin_right,
  56     eCSSEditableProperty_text_align,
  57     eCSSEditableProperty_text_decoration,
  58     eCSSEditableProperty_vertical_align,
  59     eCSSEditableProperty_whitespace,
  60     eCSSEditableProperty_width
  61   };
  62
  63   // Nb: keep these fields in an order that minimizes padding.
  64   struct CSSEquivTable {
  65     nsCSSEditableProperty cssProperty;
  66     bool gettable;
  67     bool caseSensitiveValue;
  68     nsProcessValueFunc processValueFunctor;
  69     const char* defaultValue;
  70     const char* prependValue;
  71     const char* appendValue;
  72   };
  73
  74   /**
  75    * Answers true if the given combination element_name/attribute_name
  76    * has a CSS equivalence in this implementation.
  77    *
  78    * @param aNode          [IN] A DOM node.
  79    * @param aProperty      [IN] An atom containing a HTML tag name.
  80    * @param aAttribute     [IN] An atom containing a HTML
  81    *                            attribute carried by the element above.
  82    * @return               A boolean saying if the tag/attribute has a CSS
  83    *                       equiv.
  84    */
  85   static bool IsCSSEditableProperty(nsINode* aNode, nsAtom* aProperty,
  86                                     nsAtom* aAttribute);
  87
  88   /**
  89    * Adds/remove a CSS declaration to the STYLE attribute carried by a given
  90    * element.
  91    *
  92    * @param aStyledElement [IN] A DOM styled element.
  93    * @param aProperty      [IN] An atom containing the CSS property to set.
  94    * @param aValue         [IN] A string containing the value of the CSS
  95    *                            property.
  96    */
  97   [[nodiscard]] MOZ_CAN_RUN_SCRIPT nsresult
  98   SetCSSPropertyWithTransaction(nsStyledElement& aStyledElement,
  99                                 nsAtom& aProperty, const nsAString& aValue) {
 100     return SetCSSPropertyInternal(aStyledElement, aProperty, aValue, false);
 101   }
 102   [[nodiscard]] MOZ_CAN_RUN_SCRIPT nsresult SetCSSPropertyPixelsWithTransaction(
 103       nsStyledElement& aStyledElement, nsAtom& aProperty, int32_t aIntValue);
 104   [[nodiscard]] MOZ_CAN_RUN_SCRIPT nsresult
 105   SetCSSPropertyPixelsWithoutTransaction(nsStyledElement& aStyledElement,
 106                                          const nsAtom& aProperty,
 107                                          int32_t aIntValue);
 108   [[nodiscard]] MOZ_CAN_RUN_SCRIPT nsresult RemoveCSSPropertyWithTransaction(
 109       nsStyledElement& aStyledElement, nsAtom& aProperty,
 110       const nsAString& aPropertyValue) {
 111     return RemoveCSSPropertyInternal(aStyledElement, aProperty, aPropertyValue,
 112                                      false);
 113   }
 114
 115   /**
 116    * Gets the specified/computed style value of a CSS property for a given
 117    * node (or its element ancestor if it is not an element).
 118    *
 119    * @param aContent       [IN] A DOM node.
 120    * @param aProperty      [IN] An atom containing the CSS property to get.
 121    * @param aPropertyValue [OUT] The retrieved value of the property.
 122    */
 123   static nsresult GetSpecifiedProperty(nsIContent& aContent,
 124                                        nsAtom& aCSSProperty, nsAString& aValue);
 125   MOZ_CAN_RUN_SCRIPT static nsresult GetComputedProperty(nsIContent& aContent,
 126                                                          nsAtom& aCSSProperty,
 127                                                          nsAString& aValue);
 128
 129   /**
 130    * Removes a CSS property from the specified declarations in STYLE attribute
 131    * and removes the node if it is an useless span.
 132    *
 133    * @param aStyledElement  [IN] The styled element we want to remove a style
 134    *                             from.
 135    * @param aProperty       [IN] The CSS property atom to remove.
 136    * @param aPropertyValue  [IN] The value of the property we have to remove
 137    *                             if the property accepts more than one value.
 138    */
 139   [[nodiscard]] MOZ_CAN_RUN_SCRIPT nsresult RemoveCSSInlineStyleWithTransaction(
 140       nsStyledElement& aStyledElement, nsAtom* aProperty,
 141       const nsAString& aPropertyValue);
 142
 143   /**
 144    * Answers true is the property can be removed by setting a "none" CSS value
 145    * on a node.
 146    *
 147    * @param aProperty     [IN] An atom containing a CSS property.
 148    * @param aAttribute    [IN] Pointer to an attribute name or null if this
 149    *                           information is irrelevant.
 150    * @return              A boolean saying if the property can be remove by
 151    *                      setting a "none" value.
 152    */
 153   static bool IsCSSInvertible(nsAtom& aProperty, nsAtom* aAttribute);
 154
 155   /**
 156    * Get the default browser background color if we need it for
 157    * GetCSSBackgroundColorState().
 158    *
 159    * @param aColor         [OUT] The default color as it is defined in prefs.
 160    */
 161   static void GetDefaultBackgroundColor(nsAString& aColor);
 162
 163   /**
 164    * Get the default length unit used for CSS Indent/Outdent.
 165    *
 166    * @param aLengthUnit    [OUT] The default length unit as it is defined in
 167    *                             prefs.
 168    */
 169   static void GetDefaultLengthUnit(nsAString& aLengthUnit);
 170
 171   /**
 172    * Returns the list of values for the CSS equivalences to
 173    * the passed HTML style for the passed node.
 174    *
 175    * @param aContent       [IN] A DOM node.
 176    * @param aHTMLProperty  [IN] An atom containing an HTML property.
 177    * @param aAttribute     [IN] An atom of attribute name or nullptr if
 178    *                            irrelevant.
 179    * @param aValueString   [OUT] The list of CSS values.
 180    */
 181   MOZ_CAN_RUN_SCRIPT static nsresult
 182   GetComputedCSSEquivalentToHTMLInlineStyleSet(nsIContent& aContent,
 183                                                nsAtom* aHTMLProperty,
 184                                                nsAtom* aAttribute,
 185                                                nsAString& aValue) {
 186     return GetCSSEquivalentToHTMLInlineStyleSetInternal(
 187         aContent, aHTMLProperty, aAttribute, aValue, StyleType::Computed);
 188   }
 189
 190   /**
 191    * Does the node aNode (or his parent if it is not an element node) carries
 192    * the CSS equivalent styles to the HTML style for this node ?
 193    *
 194    * @param aContent       [IN] A DOM node.
 195    * @param aHTMLProperty  [IN] An atom containing an HTML property.
 196    * @param aAttribute     [IN] A pointer/atom to an attribute name or nullptr
 197    *                            if irrelevant.
 198    * @param aValueString   [IN/OUT] The attribute value (in) the list of CSS
 199    *                                values (out).
 200    * @return               A boolean being true if the css properties are
 201    *                       not same as initial value.
 202    */
 203   MOZ_CAN_RUN_SCRIPT static bool IsComputedCSSEquivalentToHTMLInlineStyleSet(
 204       nsIContent& aContent, nsAtom* aHTMLProperty, nsAtom* aAttribute,
 205       nsAString& aValue) {
 206     MOZ_ASSERT(aHTMLProperty || aAttribute);
 207     return IsCSSEquivalentToHTMLInlineStyleSetInternal(
 208         aContent, aHTMLProperty, aAttribute, aValue, StyleType::Computed);
 209   }
 210   MOZ_CAN_RUN_SCRIPT_BOUNDARY static bool
 211   IsSpecifiedCSSEquivalentToHTMLInlineStyleSet(nsIContent& aContent,
 212                                                nsAtom* aHTMLProperty,
 213                                                nsAtom* aAttribute,
 214                                                nsAString& aValue) {
 215     MOZ_ASSERT(aHTMLProperty || aAttribute);
 216     return IsCSSEquivalentToHTMLInlineStyleSetInternal(
 217         aContent, aHTMLProperty, aAttribute, aValue, StyleType::Specified);
 218   }
 219
 220   /**
 221    * This is a kind of IsCSSEquivalentToHTMLInlineStyleSet.
 222    * IsCSSEquivalentToHTMLInlineStyleSet returns whether the properties
 223    * aren't same as initial value.  But this method returns whether the
 224    * properties aren't set.
 225    * If node is <span style="font-weight: normal"/>,
 226    *  - Is(Computed|Specified)CSSEquivalentToHTMLInlineStyleSet returns false.
 227    *  - Have(Computed|Specified)CSSEquivalentStyles returns true.
 228    *
 229    * @param aContent       [IN] A DOM node.
 230    * @param aHTMLProperty  [IN] An atom containing an HTML property.
 231    * @param aAttribute     [IN] An atom to an attribute name or nullptr
 232    *                            if irrelevant.
 233    * @return               A boolean being true if the css properties are
 234    *                       not set.
 235    */
 236   MOZ_CAN_RUN_SCRIPT static bool HaveComputedCSSEquivalentStyles(
 237       nsIContent& aContent, nsAtom* aHTMLProperty, nsAtom* aAttribute) {
 238     MOZ_ASSERT(aHTMLProperty || aAttribute);
 239     return HaveCSSEquivalentStylesInternal(aContent, aHTMLProperty, aAttribute,
 240                                            StyleType::Computed);
 241   }
 242   MOZ_CAN_RUN_SCRIPT_BOUNDARY static bool HaveSpecifiedCSSEquivalentStyles(
 243       nsIContent& aContent, nsAtom* aHTMLProperty, nsAtom* aAttribute) {
 244     MOZ_ASSERT(aHTMLProperty || aAttribute);
 245     return HaveCSSEquivalentStylesInternal(aContent, aHTMLProperty, aAttribute,
 246                                            StyleType::Specified);
 247   }
 248
 249   /**
 250    * Adds to the node the CSS inline styles equivalent to the HTML style
 251    * and return the number of CSS properties set by the call.
 252    *
 253    * @param aNode          [IN] A DOM node.
 254    * @param aHTMLProperty  [IN] An atom containing an HTML property.
 255    * @param aAttribute     [IN] An atom to an attribute name or nullptr
 256    *                            if irrelevant.
 257    * @param aValue         [IN] The attribute value.
 258    *
 259    * @return               The number of CSS properties set by the call.
 260    */
 261   [[nodiscard]] MOZ_CAN_RUN_SCRIPT Result<int32_t, nsresult>
 262   SetCSSEquivalentToHTMLStyleWithTransaction(nsStyledElement& aStyledElement,
 263                                              nsAtom* aProperty,
 264                                              nsAtom* aAttribute,
 265                                              const nsAString* aValue) {
 266     return SetCSSEquivalentToHTMLStyleInternal(aStyledElement, aProperty,
 267                                                aAttribute, aValue, false);
 268   }
 269   [[nodiscard]] MOZ_CAN_RUN_SCRIPT Result<int32_t, nsresult>
 270   SetCSSEquivalentToHTMLStyleWithoutTransaction(nsStyledElement& aStyledElement,
 271                                                 nsAtom* aProperty,
 272                                                 nsAtom* aAttribute,
 273                                                 const nsAString* aValue) {
 274     return SetCSSEquivalentToHTMLStyleInternal(aStyledElement, aProperty,
 275                                                aAttribute, aValue, true);
 276   }
 277
 278   /**
 279    * Removes from the node the CSS inline styles equivalent to the HTML style.
 280    *
 281    * @param aStyledElement [IN] A DOM Element (must not be null).
 282    * @param aHTMLProperty  [IN] An atom containing an HTML property.
 283    * @param aAttribute     [IN] An atom to an attribute name or nullptr if
 284    *                            irrelevant.
 285    * @param aValue         [IN] The attribute value.
 286    */
 287   [[nodiscard]] MOZ_CAN_RUN_SCRIPT nsresult
 288   RemoveCSSEquivalentToHTMLStyleWithTransaction(nsStyledElement& aStyledElement,
 289                                                 nsAtom* aHTMLProperty,
 290                                                 nsAtom* aAttribute,
 291                                                 const nsAString* aValue) {
 292     return RemoveCSSEquivalentToHTMLStyleInternal(aStyledElement, aHTMLProperty,
 293                                                   aAttribute, aValue, false);
 294   }
 295   [[nodiscard]] MOZ_CAN_RUN_SCRIPT nsresult
 296   RemoveCSSEquivalentToHTMLStyleWithoutTransaction(
 297       nsStyledElement& aStyledElement, nsAtom* aHTMLProperty,
 298       nsAtom* aAttribute, const nsAString* aValue) {
 299     return RemoveCSSEquivalentToHTMLStyleInternal(aStyledElement, aHTMLProperty,
 300                                                   aAttribute, aValue, true);
 301   }
 302
 303   /**
 304    * Parses a "xxxx.xxxxxuuu" string where x is a digit and u an alpha char.
 305    *
 306    * @param aString        [IN] Input string to parse.
 307    * @param aValue         [OUT] Numeric part.
 308    * @param aUnit          [OUT] Unit part.
 309    */
 310   static void ParseLength(const nsAString& aString, float* aValue,
 311                           nsAtom** aUnit);
 312
 313   /**
 314    * Sets the mIsCSSPrefChecked private member; used as callback from observer
 315    *  when the CSS pref state is changed.
 316    *
 317    * @param aIsCSSPrefChecked [IN] The new boolean state for the pref.
 318    */
 319   void SetCSSEnabled(bool aIsCSSPrefChecked);
 320
 321   /**
 322    * Retrieves the mIsCSSPrefChecked private member, true if the CSS pref is
 323    * checked, false if it is not.
 324    *
 325    * @return                 the boolean value of the CSS pref.
 326    */
 327   bool IsCSSPrefChecked() const;
 328
 329   /**
 330    * DoStyledElementsHaveSameStyle compares two elements and checks if they have
 331    * the same specified CSS declarations in the STYLE attribute. The answer is
 332    * always false if at least one of them carries an ID or a class.
 333    *
 334    * @param aStyledElement      [IN] A styled element.
 335    * @param aOtherStyledElement [IN] The other styled element.
 336    * @return                    true if the two elements are considered to
 337    *                            have same styles.
 338    */
 339   static bool DoStyledElementsHaveSameStyle(
 340       nsStyledElement& aStyledElement, nsStyledElement& aOtherStyledElement);
 341
 342  public:
 343   /**
 344    * Gets the computed style for a given element.  Can return null.
 345    */
 346   static already_AddRefed<nsComputedDOMStyle> GetComputedStyle(
 347       dom::Element* aElement);
 348
 349  private:
 350   enum class StyleType { Specified, Computed };
 351
 352   /**
 353    * Retrieves the CSS property atom from an enum.
 354    *
 355    * @param aProperty           The enum value for the property.
 356    * @return                    The corresponding atom.
 357    */
 358   static nsStaticAtom* GetCSSPropertyAtom(nsCSSEditableProperty aProperty);
 359
 360   /**
 361    * Retrieves the CSS declarations equivalent to a HTML style value for
 362    * a given equivalence table.
 363    *
 364    * @param aOutArrayOfCSSProperty  [OUT] The array of css properties.
 365    * @param aOutArrayOfCSSValue     [OUT] The array of values for the CSS
 366    *                                      properties above.
 367    * @param aEquivTable             The equivalence table.
 368    * @param aValue                  The HTML style value.
 369    * @param aGetOrRemoveRequest     A boolean value being true if the call to
 370    *                                the current method is made for
 371    *                                Get*CSSEquivalentToHTMLInlineStyleSet()
 372    *                                or
 373    *                                RemoveCSSEquivalentToHTMLInlineStyleSet().
 374    */
 375   static void BuildCSSDeclarations(
 376       nsTArray<nsStaticAtom*>& aOutArrayOfCSSProperty,
 377       nsTArray<nsString>& aOutArrayOfCSSValue, const CSSEquivTable* aEquivTable,
 378       const nsAString* aValue, bool aGetOrRemoveRequest);
 379
 380   /**
 381    * Retrieves the CSS declarations equivalent to the given HTML
 382    * property/attribute/value for a given node.
 383    *
 384    * @param aElement                The DOM node.
 385    * @param aHTMLProperty           An atom containing an HTML property.
 386    * @param aAttribute              An atom to an attribute name or nullptr
 387    *                                if irrelevant
 388    * @param aValue                  The attribute value.
 389    * @param aOutArrayOfCSSProperty  [OUT] The array of CSS properties.
 390    * @param aOutArrayOfCSSValue     [OUT] The array of values for the CSS
 391    *                                      properties above.
 392    * @param aGetOrRemoveRequest     A boolean value being true if the call to
 393    *                                the current method is made for
 394    *                                Get*CSSEquivalentToHTMLInlineStyleSet() or
 395    *                                RemoveCSSEquivalentToHTMLInlineStyleSet().
 396    */
 397   static void GenerateCSSDeclarationsFromHTMLStyle(
 398       dom::Element& aElement, nsAtom* aHTMLProperty, nsAtom* aAttribute,
 399       const nsAString* aValue, nsTArray<nsStaticAtom*>& aOutArrayOfCSSProperty,
 400       nsTArray<nsString>& aOutArrayOfCSSValue, bool aGetOrRemoveRequest);
 401
 402   /**
 403    * Back-end for GetSpecifiedProperty and GetComputedProperty.
 404    *
 405    * @param aNode               [IN] A DOM node.
 406    * @param aProperty           [IN] A CSS property.
 407    * @param aValue              [OUT] The retrieved value for this property.
 408    */
 409   MOZ_CAN_RUN_SCRIPT static nsresult GetComputedCSSInlinePropertyBase(
 410       nsIContent& aContent, nsAtom& aCSSProperty, nsAString& aValue);
 411   static nsresult GetSpecifiedCSSInlinePropertyBase(nsIContent& aContent,
 412                                                     nsAtom& aCSSProperty,
 413                                                     nsAString& aValue);
 414
 415   /**
 416    * Those methods are wrapped with corresponding methods which do not have
 417    * "Internal" in their names.  Don't use these methods directly even if
 418    * you want to use one of them in this class.
 419    * Note that these methods may run scrip only when StyleType is Computed.
 420    */
 421   MOZ_CAN_RUN_SCRIPT static nsresult
 422   GetCSSEquivalentToHTMLInlineStyleSetInternal(nsIContent& aContent,
 423                                                nsAtom* aHTMLProperty,
 424                                                nsAtom* aAttribute,
 425                                                nsAString& aValue,
 426                                                StyleType aStyleType);
 427   MOZ_CAN_RUN_SCRIPT static bool IsCSSEquivalentToHTMLInlineStyleSetInternal(
 428       nsIContent& aContent, nsAtom* aHTMLProperty, nsAtom* aAttribute,
 429       nsAString& aValue, StyleType aStyleType);
 430   MOZ_CAN_RUN_SCRIPT static bool HaveCSSEquivalentStylesInternal(
 431       nsIContent& aContent, nsAtom* aHTMLProperty, nsAtom* aAttribute,
 432       StyleType aStyleType);
 433
 434   [[nodiscard]] MOZ_CAN_RUN_SCRIPT nsresult RemoveCSSPropertyInternal(
 435       nsStyledElement& aStyledElement, nsAtom& aProperty,
 436       const nsAString& aPropertyValue, bool aSuppressTxn = false);
 437   [[nodiscard]] MOZ_CAN_RUN_SCRIPT nsresult
 438   RemoveCSSEquivalentToHTMLStyleInternal(nsStyledElement& aStyledElement,
 439                                          nsAtom* aHTMLProperty,
 440                                          nsAtom* aAttribute,
 441                                          const nsAString* aValue,
 442                                          bool aSuppressTransaction);
 443   [[nodiscard]] MOZ_CAN_RUN_SCRIPT nsresult
 444   SetCSSPropertyInternal(nsStyledElement& aStyledElement, nsAtom& aProperty,
 445                          const nsAString& aValue, bool aSuppressTxn = false);
 446   [[nodiscard]] MOZ_CAN_RUN_SCRIPT Result<int32_t, nsresult>
 447   SetCSSEquivalentToHTMLStyleInternal(nsStyledElement& aStyledElement,
 448                                       nsAtom* aProperty, nsAtom* aAttribute,
 449                                       const nsAString* aValue,
 450                                       bool aSuppressTransaction);
 451
 452  private:
 453   HTMLEditor* mHTMLEditor;
 454   bool mIsCSSPrefChecked;
 455 };
 456
 457 #define NS_EDITOR_INDENT_INCREMENT_IN 0.4134f
 458 #define NS_EDITOR_INDENT_INCREMENT_CM 1.05f
 459 #define NS_EDITOR_INDENT_INCREMENT_MM 10.5f
 460 #define NS_EDITOR_INDENT_INCREMENT_PT 29.76f
 461 #define NS_EDITOR_INDENT_INCREMENT_PC 2.48f
 462 #define NS_EDITOR_INDENT_INCREMENT_EM 3
 463 #define NS_EDITOR_INDENT_INCREMENT_EX 6
 464 #define NS_EDITOR_INDENT_INCREMENT_PX 40
 465 #define NS_EDITOR_INDENT_INCREMENT_PERCENT 4
 466
 467 }  // namespace mozilla
 468
 469 #endif  // #ifndef mozilla_CSSEditUtils_h