tor-browser

MappedDeclarationsBuilder.h (7199B)

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/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

/* Representation of a declaration block used for attribute mapping */

#ifndef mozilla_MappedDeclarationsBuilder_h
#define mozilla_MappedDeclarationsBuilder_h

#include "NonCustomCSSPropertyId.h"
#include "mozilla/FontPropertyTypes.h"
#include "mozilla/ServoBindingTypes.h"
#include "mozilla/ServoBindings.h"
#include "mozilla/dom/Element.h"
#include "nsCSSValue.h"
#include "nsColor.h"

class nsAttrValue;

namespace mozilla {

// This provides a convenient interface for attribute mappers
// (MapAttributesIntoRule) to modify the presentation attribute declaration
// block for a given element.
class MOZ_STACK_CLASS MappedDeclarationsBuilder final {
public:
 explicit MappedDeclarationsBuilder(
     dom::Element& aElement, dom::Document& aDoc,
     StyleLockedDeclarationBlock* aDecls = nullptr)
     : mDocument(aDoc), mElement(aElement), mDecls(aDecls) {
   if (mDecls) {
     Servo_DeclarationBlock_Clear(mDecls);
   }
 }

 ~MappedDeclarationsBuilder() {
   MOZ_ASSERT(!mDecls, "Forgot to take the block?");
 }

 dom::Document& Document() { return mDocument; }

 already_AddRefed<StyleLockedDeclarationBlock> TakeDeclarationBlock() {
   return mDecls.forget();
 }

 // Check if we already contain a certain longhand
 bool PropertyIsSet(NonCustomCSSPropertyId aId) const {
   return mDecls && Servo_DeclarationBlock_PropertyIsSet(mDecls, aId);
 }

 // Set a property to an identifier (string)
 void SetIdentStringValue(NonCustomCSSPropertyId aId, const nsString& aValue) {
   RefPtr<nsAtom> atom = NS_AtomizeMainThread(aValue);
   SetIdentAtomValue(aId, atom);
 }

 void SetIdentStringValueIfUnset(NonCustomCSSPropertyId aId,
                                 const nsString& aValue) {
   if (!PropertyIsSet(aId)) {
     SetIdentStringValue(aId, aValue);
   }
 }

 void SetIdentAtomValue(NonCustomCSSPropertyId aId, nsAtom* aValue);

 void SetIdentAtomValueIfUnset(NonCustomCSSPropertyId aId, nsAtom* aValue) {
   if (!PropertyIsSet(aId)) {
     SetIdentAtomValue(aId, aValue);
   }
 }

 // Set a property to a keyword (usually NS_STYLE_* or StyleFoo::*)
 void SetKeywordValue(NonCustomCSSPropertyId aId, int32_t aValue) {
   Servo_DeclarationBlock_SetKeywordValue(&EnsureDecls(), aId, aValue);
 }

 void SetKeywordValueIfUnset(NonCustomCSSPropertyId aId, int32_t aValue) {
   if (!PropertyIsSet(aId)) {
     SetKeywordValue(aId, aValue);
   }
 }

 template <typename T,
           typename = typename std::enable_if<std::is_enum<T>::value>::type>
 void SetKeywordValue(NonCustomCSSPropertyId aId, T aValue) {
   static_assert(EnumTypeFitsWithin<T, int32_t>::value,
                 "aValue must be an enum that fits within 32 bits");
   SetKeywordValue(aId, static_cast<int32_t>(aValue));
 }
 template <typename T,
           typename = typename std::enable_if<std::is_enum<T>::value>::type>
 void SetKeywordValueIfUnset(NonCustomCSSPropertyId aId, T aValue) {
   static_assert(EnumTypeFitsWithin<T, int32_t>::value,
                 "aValue must be an enum that fits within 32 bits");
   SetKeywordValueIfUnset(aId, static_cast<int32_t>(aValue));
 }

 // Set a property to an integer value
 void SetIntValue(NonCustomCSSPropertyId aId, int32_t aValue) {
   Servo_DeclarationBlock_SetIntValue(&EnsureDecls(), aId, aValue);
 }

 // Set "math-depth: <integer>" or "math-depth: add(<integer>)"
 void SetMathDepthValue(int32_t aValue, bool aIsRelative) {
   Servo_DeclarationBlock_SetMathDepthValue(&EnsureDecls(), aValue,
                                            aIsRelative);
 }

 // Set "counter-reset: list-item <integer>".  If aIsReversed is true then
 // "list-item" instead becomes "reversed(list-item)".
 void SetCounterResetListItem(int32_t aValue, bool aIsReversed) {
   Servo_DeclarationBlock_SetCounterResetListItem(&EnsureDecls(), aValue,
                                                  aIsReversed);
 }

 // Set "counter-set: list-item <integer>".
 void SetCounterSetListItem(int32_t aValue) {
   Servo_DeclarationBlock_SetCounterSetListItem(&EnsureDecls(), aValue);
 }

 // Set a property to a pixel value
 void SetPixelValue(NonCustomCSSPropertyId aId, float aValue) {
   Servo_DeclarationBlock_SetPixelValue(&EnsureDecls(), aId, aValue);
 }

 void SetPixelValueIfUnset(NonCustomCSSPropertyId aId, float aValue) {
   if (!PropertyIsSet(aId)) {
     SetPixelValue(aId, aValue);
   }
 }

 void SetLengthValue(NonCustomCSSPropertyId aId, const nsCSSValue& aValue) {
   MOZ_ASSERT(aValue.IsLengthUnit());
   Servo_DeclarationBlock_SetLengthValue(
       &EnsureDecls(), aId, aValue.GetFloatValue(), aValue.GetUnit());
 }

 // Set a property to a percent value
 void SetPercentValue(NonCustomCSSPropertyId aId, float aValue) {
   Servo_DeclarationBlock_SetPercentValue(&EnsureDecls(), aId, aValue);
 }

 void SetPercentValueIfUnset(NonCustomCSSPropertyId aId, float aValue) {
   if (!PropertyIsSet(aId)) {
     SetPercentValue(aId, aValue);
   }
 }

 // Set a property to `auto`
 void SetAutoValue(NonCustomCSSPropertyId aId) {
   Servo_DeclarationBlock_SetAutoValue(&EnsureDecls(), aId);
 }

 void SetAutoValueIfUnset(NonCustomCSSPropertyId aId) {
   if (!PropertyIsSet(aId)) {
     SetAutoValue(aId);
   }
 }

 // Set a property to `currentcolor`
 void SetCurrentColor(NonCustomCSSPropertyId aId) {
   Servo_DeclarationBlock_SetCurrentColor(&EnsureDecls(), aId);
 }

 void SetCurrentColorIfUnset(NonCustomCSSPropertyId aId) {
   if (!PropertyIsSet(aId)) {
     SetCurrentColor(aId);
   }
 }

 // Set a property to an RGBA nscolor value
 void SetColorValue(NonCustomCSSPropertyId aId, nscolor aValue) {
   Servo_DeclarationBlock_SetColorValue(&EnsureDecls(), aId, aValue);
 }

 void SetColorValueIfUnset(NonCustomCSSPropertyId aId, nscolor aValue) {
   if (!PropertyIsSet(aId)) {
     SetColorValue(aId, aValue);
   }
 }

 // Set font-family to a string
 void SetFontFamily(const nsACString& aValue) {
   Servo_DeclarationBlock_SetFontFamily(&EnsureDecls(), &aValue);
 }

 // Add a quirks-mode override to the decoration color of elements nested in
 // <a>
 void SetTextDecorationColorOverride() {
   Servo_DeclarationBlock_SetTextDecorationColorOverride(&EnsureDecls());
 }

 void SetBackgroundImage(const nsAttrValue& value);

 void SetAspectRatio(float aWidth, float aHeight) {
   Servo_DeclarationBlock_SetAspectRatio(&EnsureDecls(), aWidth, aHeight);
 }

 const nsAttrValue* GetAttr(nsAtom* aName) {
   MOZ_ASSERT(mElement.IsAttributeMapped(aName));
   return mElement.GetParsedAttr(aName);
 }

private:
 StyleLockedDeclarationBlock& EnsureDecls() {
   if (!mDecls) {
     mDecls = Servo_DeclarationBlock_CreateEmpty().Consume();
   }
   return *mDecls;
 }

 dom::Document& mDocument;
 dom::Element& mElement;
 RefPtr<StyleLockedDeclarationBlock> mDecls;
};

}  // namespace mozilla

#endif