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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/. */

#include "nsMathMLElement.h"
#include "base/compiler_specific.h"
#include "mozilla/ArrayUtils.h"
#include "nsGkAtoms.h"
#include "nsITableCellLayout.h"  // for MAX_COLSPAN / MAX_ROWSPAN
#include "nsCRT.h"
#include "nsLayoutStylesheetCache.h"
#ifdef MOZ_OLD_STYLE
#include "nsRuleData.h"
#endif
#include "nsCSSValue.h"
#include "nsCSSParser.h"
#include "nsMappedAttributes.h"
#include "nsStyleConsts.h"
#include "nsIDocument.h"
#include "nsIPresShell.h"
#include "nsPresContext.h"
#include "mozAutoDocUpdate.h"
#include "nsIScriptError.h"
#include "nsContentUtils.h"
#include "nsIURI.h"

#include "mozilla/EventDispatcher.h"
#include "mozilla/EventStates.h"
#include "mozilla/GenericSpecifiedValuesInlines.h"
#include "mozilla/dom/ElementBinding.h"

using namespace mozilla;
using namespace mozilla::dom;

//----------------------------------------------------------------------
// nsISupports methods:

NS_IMPL_ISUPPORTS_INHERITED(nsMathMLElement, nsMathMLElementBase, nsIDOMElement,
                            nsIDOMNode, Link)

static nsresult WarnDeprecated(const char16_t* aDeprecatedAttribute,
                               const char16_t* aFavoredAttribute,
                               nsIDocument* aDocument) {
  const char16_t* argv[] = {aDeprecatedAttribute, aFavoredAttribute};
  return nsContentUtils::ReportToConsole(
      nsIScriptError::warningFlag, NS_LITERAL_CSTRING("MathML"), aDocument,
      nsContentUtils::eMATHML_PROPERTIES, "DeprecatedSupersededBy", argv, 2);
}

static nsresult ReportLengthParseError(const nsString& aValue,
                                       nsIDocument* aDocument) {
  const char16_t* arg = aValue.get();
  return nsContentUtils::ReportToConsole(
      nsIScriptError::errorFlag, NS_LITERAL_CSTRING("MathML"), aDocument,
      nsContentUtils::eMATHML_PROPERTIES, "LengthParsingError", &arg, 1);
}

static nsresult ReportParseErrorNoTag(const nsString& aValue, nsAtom* aAtom,
                                      nsIDocument* aDocument) {
  const char16_t* argv[] = {aValue.get(), aAtom->GetUTF16String()};
  return nsContentUtils::ReportToConsole(
      nsIScriptError::errorFlag, NS_LITERAL_CSTRING("MathML"), aDocument,
      nsContentUtils::eMATHML_PROPERTIES, "AttributeParsingErrorNoTag", argv,
      2);
}

nsMathMLElement::nsMathMLElement(
    already_AddRefed<mozilla::dom::NodeInfo>& aNodeInfo)
    : nsMathMLElementBase(aNodeInfo),
      ALLOW_THIS_IN_INITIALIZER_LIST(Link(this)),
      mIncrementScriptLevel(false) {}

nsMathMLElement::nsMathMLElement(
    already_AddRefed<mozilla::dom::NodeInfo>&& aNodeInfo)
    : nsMathMLElementBase(aNodeInfo),
      ALLOW_THIS_IN_INITIALIZER_LIST(Link(this)),
      mIncrementScriptLevel(false) {}

nsresult nsMathMLElement::BindToTree(nsIDocument* aDocument,
                                     nsIContent* aParent,
                                     nsIContent* aBindingParent,
                                     bool aCompileEventHandlers) {
  Link::ResetLinkState(false, Link::ElementHasHref());

  nsresult rv = nsMathMLElementBase::BindToTree(
      aDocument, aParent, aBindingParent, aCompileEventHandlers);
  NS_ENSURE_SUCCESS(rv, rv);

  if (aDocument) {
    aDocument->RegisterPendingLinkUpdate(this);
  }

  nsIDocument* doc = GetComposedDoc();
  if (doc) {
    if (!doc->GetMathMLEnabled()) {
      // Enable MathML and setup the style sheet during binding, not element
      // construction, because we could move a MathML element from the document
      // that created it to another document.
      auto cache = nsLayoutStylesheetCache::For(doc->GetStyleBackendType());
      doc->SetMathMLEnabled();
      doc->EnsureOnDemandBuiltInUASheet(cache->MathMLSheet());

      // Rebuild style data for the presshell, because style system
      // optimizations may have taken place assuming MathML was disabled.
      // (See nsRuleNode::CheckSpecifiedProperties.)
      RefPtr<nsPresContext> presContext = doc->GetPresContext();
      if (presContext) {
        presContext->PostRebuildAllStyleDataEvent(nsChangeHint(0),
                                                  eRestyle_Subtree);
      }
    }
  }

  return rv;
}

void nsMathMLElement::UnbindFromTree(bool aDeep, bool aNullParent) {
  // If this link is ever reinserted into a document, it might
  // be under a different xml:base, so forget the cached state now.
  Link::ResetLinkState(false, Link::ElementHasHref());

  nsMathMLElementBase::UnbindFromTree(aDeep, aNullParent);
}

bool nsMathMLElement::ParseAttribute(int32_t aNamespaceID, nsAtom* aAttribute,
                                     const nsAString& aValue,
                                     nsIPrincipal* aMaybeScriptedPrincipal,
                                     nsAttrValue& aResult) {
  MOZ_ASSERT(IsMathMLElement());

  if (aNamespaceID == kNameSpaceID_None) {
    if (mNodeInfo->Equals(nsGkAtoms::math) && aAttribute == nsGkAtoms::mode) {
      WarnDeprecated(nsGkAtoms::mode->GetUTF16String(),
                     nsGkAtoms::display->GetUTF16String(), OwnerDoc());
    }
    if (aAttribute == nsGkAtoms::color) {
      WarnDeprecated(nsGkAtoms::color->GetUTF16String(),
                     nsGkAtoms::mathcolor_->GetUTF16String(), OwnerDoc());
    }
    if (aAttribute == nsGkAtoms::color || aAttribute == nsGkAtoms::mathcolor_ ||
        aAttribute == nsGkAtoms::background ||
        aAttribute == nsGkAtoms::mathbackground_) {
      return aResult.ParseColor(aValue);
    }
    if (mNodeInfo->Equals(nsGkAtoms::mtd_)) {
      if (aAttribute == nsGkAtoms::columnspan_) {
        aResult.ParseClampedNonNegativeInt(aValue, 1, 1, MAX_COLSPAN);
        return true;
      }
      if (aAttribute == nsGkAtoms::rowspan) {
        aResult.ParseClampedNonNegativeInt(aValue, 1, 0, MAX_ROWSPAN);
        return true;
      }
    }
  }

  return nsMathMLElementBase::ParseAttribute(aNamespaceID, aAttribute, aValue,
                                             aMaybeScriptedPrincipal, aResult);
}

static Element::MappedAttributeEntry sMtableStyles[] = {{&nsGkAtoms::width},
                                                        {nullptr}};

static Element::MappedAttributeEntry sTokenStyles[] = {
    {&nsGkAtoms::mathsize_},    {&nsGkAtoms::fontsize_},
    {&nsGkAtoms::color},        {&nsGkAtoms::fontfamily_},
    {&nsGkAtoms::fontstyle_},   {&nsGkAtoms::fontweight_},
    {&nsGkAtoms::mathvariant_}, {nullptr}};

static Element::MappedAttributeEntry sEnvironmentStyles[] = {
    {&nsGkAtoms::scriptlevel_},
    {&nsGkAtoms::scriptminsize_},
    {&nsGkAtoms::scriptsizemultiplier_},
    {&nsGkAtoms::background},
    {nullptr}};

static Element::MappedAttributeEntry sCommonPresStyles[] = {
    {&nsGkAtoms::mathcolor_}, {&nsGkAtoms::mathbackground_}, {nullptr}};

static Element::MappedAttributeEntry sDirStyles[] = {{&nsGkAtoms::dir},
                                                     {nullptr}};

bool nsMathMLElement::IsAttributeMapped(const nsAtom* aAttribute) const {
  MOZ_ASSERT(IsMathMLElement());

  static const MappedAttributeEntry* const mtableMap[] = {sMtableStyles,
                                                          sCommonPresStyles};
  static const MappedAttributeEntry* const tokenMap[] = {
      sTokenStyles, sCommonPresStyles, sDirStyles};
  static const MappedAttributeEntry* const mstyleMap[] = {
      sTokenStyles, sEnvironmentStyles, sCommonPresStyles, sDirStyles};
  static const MappedAttributeEntry* const commonPresMap[] = {
      sCommonPresStyles};
  static const MappedAttributeEntry* const mrowMap[] = {sCommonPresStyles,
                                                        sDirStyles};

  // We don't support mglyph (yet).
  if (IsAnyOfMathMLElements(nsGkAtoms::ms_, nsGkAtoms::mi_, nsGkAtoms::mn_,
                            nsGkAtoms::mo_, nsGkAtoms::mtext_,
                            nsGkAtoms::mspace_))
    return FindAttributeDependence(aAttribute, tokenMap);
  if (IsAnyOfMathMLElements(nsGkAtoms::mstyle_, nsGkAtoms::math))
    return FindAttributeDependence(aAttribute, mstyleMap);

  if (mNodeInfo->Equals(nsGkAtoms::mtable_))
    return FindAttributeDependence(aAttribute, mtableMap);

  if (mNodeInfo->Equals(nsGkAtoms::mrow_))
    return FindAttributeDependence(aAttribute, mrowMap);

  if (IsAnyOfMathMLElements(
          nsGkAtoms::maction_, nsGkAtoms::maligngroup_, nsGkAtoms::malignmark_,
          nsGkAtoms::menclose_, nsGkAtoms::merror_, nsGkAtoms::mfenced_,
          nsGkAtoms::mfrac_, nsGkAtoms::mover_, nsGkAtoms::mpadded_,
          nsGkAtoms::mphantom_, nsGkAtoms::mprescripts_, nsGkAtoms::mroot_,
          nsGkAtoms::msqrt_, nsGkAtoms::msub_, nsGkAtoms::msubsup_,
          nsGkAtoms::msup_, nsGkAtoms::mtd_, nsGkAtoms::mtr_,
          nsGkAtoms::munder_, nsGkAtoms::munderover_, nsGkAtoms::none)) {
    return FindAttributeDependence(aAttribute, commonPresMap);
  }

  return false;
}

nsMapRuleToAttributesFunc nsMathMLElement::GetAttributeMappingFunction() const {
  // It doesn't really matter what our tag is here, because only attributes
  // that satisfy IsAttributeMapped will be stored in the mapped attributes
  // list and available to the mapping function
  return &MapMathMLAttributesInto;
}

/* static */ bool nsMathMLElement::ParseNamedSpaceValue(const nsString& aString,
                                                        nsCSSValue& aCSSValue,
                                                        uint32_t aFlags) {
  int32_t i = 0;
  // See if it is one of the 'namedspace' (ranging -7/18em, -6/18, ... 7/18em)
  if (aString.EqualsLiteral("veryverythinmathspace")) {
    i = 1;
  } else if (aString.EqualsLiteral("verythinmathspace")) {
    i = 2;
  } else if (aString.EqualsLiteral("thinmathspace")) {
    i = 3;
  } else if (aString.EqualsLiteral("mediummathspace")) {
    i = 4;
  } else if (aString.EqualsLiteral("thickmathspace")) {
    i = 5;
  } else if (aString.EqualsLiteral("verythickmathspace")) {
    i = 6;
  } else if (aString.EqualsLiteral("veryverythickmathspace")) {
    i = 7;
  } else if (aFlags & PARSE_ALLOW_NEGATIVE) {
    if (aString.EqualsLiteral("negativeveryverythinmathspace")) {
      i = -1;
    } else if (aString.EqualsLiteral("negativeverythinmathspace")) {
      i = -2;
    } else if (aString.EqualsLiteral("negativethinmathspace")) {
      i = -3;
    } else if (aString.EqualsLiteral("negativemediummathspace")) {
      i = -4;
    } else if (aString.EqualsLiteral("negativethickmathspace")) {
      i = -5;
    } else if (aString.EqualsLiteral("negativeverythickmathspace")) {
      i = -6;
    } else if (aString.EqualsLiteral("negativeveryverythickmathspace")) {
      i = -7;
    }
  }
  if (0 != i) {
    aCSSValue.SetFloatValue(float(i) / float(18), eCSSUnit_EM);
    return true;
  }

  return false;
}

// The REC says:
//
// "Most presentation elements have attributes that accept values representing
// lengths to be used for size, spacing or similar properties. The syntax of a
// length is specified as
//
// number | number unit | namedspace
//
// There should be no space between the number and the unit of a length."
//
// "A trailing '%' represents a percent of the default value. The default
// value, or how it is obtained, is listed in the table of attributes for each
// element. [...] A number without a unit is intepreted as a multiple of the
// default value."
//
// "The possible units in MathML are:
//
// Unit Description
// em   an em (font-relative unit traditionally used for horizontal lengths)
// ex   an ex (font-relative unit traditionally used for vertical lengths)
// px   pixels, or size of a pixel in the current display
// in   inches (1 inch = 2.54 centimeters)
// cm   centimeters
// mm   millimeters
// pt   points (1 point = 1/72 inch)
// pc   picas (1 pica = 12 points)
// %    percentage of default value"
//
// The numbers are defined that way:
// - unsigned-number: "a string of decimal digits with up to one decimal point
//   (U+002E), representing a non-negative terminating decimal number (a type of
//   rational number)"
// - number: "an optional prefix of '-' (U+002D), followed by an unsigned
//   number, representing a terminating decimal number (a type of rational
//   number)"
//
/* static */ bool nsMathMLElement::ParseNumericValue(const nsString& aString,
                                                     nsCSSValue& aCSSValue,
                                                     uint32_t aFlags,
                                                     nsIDocument* aDocument) {
  nsAutoString str(aString);
  str.CompressWhitespace();  // aString is const in this code...

  int32_t stringLength = str.Length();
  if (!stringLength) {
    if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
      ReportLengthParseError(aString, aDocument);
    }
    return false;
  }

  if (ParseNamedSpaceValue(str, aCSSValue, aFlags)) {
    return true;
  }

  nsAutoString number, unit;

  // see if the negative sign is there
  int32_t i = 0;
  char16_t c = str[0];
  if (c == '-') {
    number.Append(c);
    i++;
  }

  // Gather up characters that make up the number
  bool gotDot = false;
  for (; i < stringLength; i++) {
    c = str[i];
    if (gotDot && c == '.') {
      if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
        ReportLengthParseError(aString, aDocument);
      }
      return false;  // two dots encountered
    } else if (c == '.')
      gotDot = true;
    else if (!nsCRT::IsAsciiDigit(c)) {
      str.Right(unit, stringLength - i);
      // some authors leave blanks before the unit, but that shouldn't
      // be allowed, so don't CompressWhitespace on 'unit'.
      break;
    }
    number.Append(c);
  }

  // Convert number to floating point
  nsresult errorCode;
  float floatValue = number.ToFloat(&errorCode);
  if (NS_FAILED(errorCode)) {
    if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
      ReportLengthParseError(aString, aDocument);
    }
    return false;
  }
  if (floatValue < 0 && !(aFlags & PARSE_ALLOW_NEGATIVE)) {
    if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
      ReportLengthParseError(aString, aDocument);
    }
    return false;
  }

  nsCSSUnit cssUnit;
  if (unit.IsEmpty()) {
    if (aFlags & PARSE_ALLOW_UNITLESS) {
      // no explicit unit, this is a number that will act as a multiplier
      if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
        nsContentUtils::ReportToConsole(nsIScriptError::warningFlag,
                                        NS_LITERAL_CSTRING("MathML"), aDocument,
                                        nsContentUtils::eMATHML_PROPERTIES,
                                        "UnitlessValuesAreDeprecated");
      }
      if (aFlags & CONVERT_UNITLESS_TO_PERCENT) {
        aCSSValue.SetPercentValue(floatValue);
        return true;
      } else
        cssUnit = eCSSUnit_Number;
    } else {
      // We are supposed to have a unit, but there isn't one.
      // If the value is 0 we can just call it "pixels" otherwise
      // this is illegal.
      if (floatValue != 0.0) {
        if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
          ReportLengthParseError(aString, aDocument);
        }
        return false;
      }
      cssUnit = eCSSUnit_Pixel;
    }
  } else if (unit.EqualsLiteral("%")) {
    aCSSValue.SetPercentValue(floatValue / 100.0f);
    return true;
  } else if (unit.EqualsLiteral("em"))
    cssUnit = eCSSUnit_EM;
  else if (unit.EqualsLiteral("ex"))
    cssUnit = eCSSUnit_XHeight;
  else if (unit.EqualsLiteral("px"))
    cssUnit = eCSSUnit_Pixel;
  else if (unit.EqualsLiteral("in"))
    cssUnit = eCSSUnit_Inch;
  else if (unit.EqualsLiteral("cm"))
    cssUnit = eCSSUnit_Centimeter;
  else if (unit.EqualsLiteral("mm"))
    cssUnit = eCSSUnit_Millimeter;
  else if (unit.EqualsLiteral("pt"))
    cssUnit = eCSSUnit_Point;
  else if (unit.EqualsLiteral("pc"))
    cssUnit = eCSSUnit_Pica;
  else if (unit.EqualsLiteral("q"))
    cssUnit = eCSSUnit_Quarter;
  else {  // unexpected unit
    if (!(aFlags & PARSE_SUPPRESS_WARNINGS)) {
      ReportLengthParseError(aString, aDocument);
    }
    return false;
  }

  aCSSValue.SetFloatValue(floatValue, cssUnit);
  return true;
}

void nsMathMLElement::MapMathMLAttributesInto(
    const nsMappedAttributes* aAttributes, GenericSpecifiedValues* aData) {
  if (aData->mSIDs & NS_STYLE_INHERIT_BIT(Font)) {
    // scriptsizemultiplier
    //
    // "Specifies the multiplier to be used to adjust font size due to changes
    // in scriptlevel.
    //
    // values: number
    // default: 0.71
    //
    const nsAttrValue* value =
        aAttributes->GetAttr(nsGkAtoms::scriptsizemultiplier_);
    if (value && value->Type() == nsAttrValue::eString &&
        !aData->PropertyIsSet(eCSSProperty__moz_script_size_multiplier)) {
      nsAutoString str(value->GetStringValue());
      str.CompressWhitespace();
      // MathML numbers can't have leading '+'
      if (str.Length() > 0 && str.CharAt(0) != '+') {
        nsresult errorCode;
        float floatValue = str.ToFloat(&errorCode);
        // Negative scriptsizemultipliers are not parsed
        if (NS_SUCCEEDED(errorCode) && floatValue >= 0.0f) {
          aData->SetNumberValue(eCSSProperty__moz_script_size_multiplier,
                                floatValue);
        } else {
          ReportParseErrorNoTag(str, nsGkAtoms::scriptsizemultiplier_,
                                aData->Document());
        }
      }
    }

    // scriptminsize
    //
    // "Specifies the minimum font size allowed due to changes in scriptlevel.
    // Note that this does not limit the font size due to changes to mathsize."
    //
    // values: length
    // default: 8pt
    //
    // We don't allow negative values.
    // Unitless and percent values give a multiple of the default value.
    //
    value = aAttributes->GetAttr(nsGkAtoms::scriptminsize_);
    if (value && value->Type() == nsAttrValue::eString &&
        !aData->PropertyIsSet(eCSSProperty__moz_script_min_size)) {
      nsCSSValue scriptMinSize;
      ParseNumericValue(value->GetStringValue(), scriptMinSize,
                        PARSE_ALLOW_UNITLESS | CONVERT_UNITLESS_TO_PERCENT,
                        aData->Document());

      if (scriptMinSize.GetUnit() == eCSSUnit_Percent) {
        scriptMinSize.SetFloatValue(8.0 * scriptMinSize.GetPercentValue(),
                                    eCSSUnit_Point);
      }
      if (scriptMinSize.GetUnit() != eCSSUnit_Null) {
        aData->SetLengthValue(eCSSProperty__moz_script_min_size, scriptMinSize);
      }
    }

    // scriptlevel
    //
    // "Changes the scriptlevel in effect for the children. When the value is
    // given without a sign, it sets scriptlevel to the specified value; when a
    // sign is given, it increments ("+") or decrements ("-") the current
    // value. (Note that large decrements can result in negative values of
    // scriptlevel, but these values are considered legal.)"
    //
    // values: ( "+" | "-" )? unsigned-integer
    // default: inherited
    //
    value = aAttributes->GetAttr(nsGkAtoms::scriptlevel_);
    if (value && value->Type() == nsAttrValue::eString &&
        !aData->PropertyIsSet(eCSSProperty__moz_script_level)) {
      nsAutoString str(value->GetStringValue());
      str.CompressWhitespace();
      if (str.Length() > 0) {
        nsresult errorCode;
        int32_t intValue = str.ToInteger(&errorCode);
        if (NS_SUCCEEDED(errorCode)) {
          // This is kind of cheesy ... if the scriptlevel has a sign,
          // then it's a relative value and we store the nsCSSValue as an
          // Integer to indicate that. Otherwise we store it as a Number
          // to indicate that the scriptlevel is absolute.
          char16_t ch = str.CharAt(0);
          if (ch == '+' || ch == '-') {
            aData->SetIntValue(eCSSProperty__moz_script_level, intValue);
          } else {
            aData->SetNumberValue(eCSSProperty__moz_script_level, intValue);
          }
        } else {
          ReportParseErrorNoTag(str, nsGkAtoms::scriptlevel_,
                                aData->Document());
        }
      }
    }

    // mathsize
    //
    // "Specifies the size to display the token content. The values 'small' and
    // 'big' choose a size smaller or larger than the current font size, but
    // leave the exact proportions unspecified; 'normal' is allowed for
    // completeness, but since it is equivalent to '100%' or '1em', it has no
    // effect."
    //
    // values: "small" | "normal" | "big" | length
    // default: inherited
    //
    // fontsize
    //
    // "Specified the size for the token. Deprecated in favor of mathsize."
    //
    // values: length
    // default: inherited
    //
    // In both cases, we don't allow negative values.
    // Unitless values give a multiple of the default value.
    //
    bool parseSizeKeywords = true;
    value = aAttributes->GetAttr(nsGkAtoms::mathsize_);
    if (!value) {
      parseSizeKeywords = false;
      value = aAttributes->GetAttr(nsGkAtoms::fontsize_);
      if (value) {
        WarnDeprecated(nsGkAtoms::fontsize_->GetUTF16String(),
                       nsGkAtoms::mathsize_->GetUTF16String(),
                       aData->Document());
      }
    }
    if (value && value->Type() == nsAttrValue::eString &&
        !aData->PropertyIsSet(eCSSProperty_font_size)) {
      nsAutoString str(value->GetStringValue());
      nsCSSValue fontSize;
      if (!ParseNumericValue(str, fontSize,
                             PARSE_SUPPRESS_WARNINGS | PARSE_ALLOW_UNITLESS |
                                 CONVERT_UNITLESS_TO_PERCENT,
                             nullptr) &&
          parseSizeKeywords) {
        static const char sizes[3][7] = {"small", "normal", "big"};
        static const int32_t values[MOZ_ARRAY_LENGTH(sizes)] = {
            NS_STYLE_FONT_SIZE_SMALL, NS_STYLE_FONT_SIZE_MEDIUM,
            NS_STYLE_FONT_SIZE_LARGE};
        str.CompressWhitespace();
        for (uint32_t i = 0; i < ArrayLength(sizes); ++i) {
          if (str.EqualsASCII(sizes[i])) {
            aData->SetKeywordValue(eCSSProperty_font_size, values[i]);
            break;
          }
        }
      } else if (fontSize.GetUnit() == eCSSUnit_Percent) {
        aData->SetPercentValue(eCSSProperty_font_size,
                               fontSize.GetPercentValue());
      } else if (fontSize.GetUnit() != eCSSUnit_Null) {
        aData->SetLengthValue(eCSSProperty_font_size, fontSize);
      }
    }

    // fontfamily
    //
    // "Should be the name of a font that may be available to a MathML renderer,
    // or a CSS font specification; See Section 6.5 Using CSS with MathML and
    // CSS for more information. Deprecated in favor of mathvariant."
    //
    // values: string
    //
    value = aAttributes->GetAttr(nsGkAtoms::fontfamily_);
    if (value) {
      WarnDeprecated(nsGkAtoms::fontfamily_->GetUTF16String(),
                     nsGkAtoms::mathvariant_->GetUTF16String(),
                     aData->Document());
    }
    if (value && value->Type() == nsAttrValue::eString &&
        !aData->PropertyIsSet(eCSSProperty_font_family)) {
      aData->SetFontFamily(value->GetStringValue());
    }

    // fontstyle
    //
    // "Specified the font style to use for the token. Deprecated in favor of
    //  mathvariant."
    //
    // values: "normal" | "italic"
    // default:	normal (except on <mi>)
    //
    // Note that the font-style property is reset in layout/style/ when
    // -moz-math-variant is specified.
    value = aAttributes->GetAttr(nsGkAtoms::fontstyle_);
    if (value) {
      WarnDeprecated(nsGkAtoms::fontstyle_->GetUTF16String(),
                     nsGkAtoms::mathvariant_->GetUTF16String(),
                     aData->Document());
      if (value->Type() == nsAttrValue::eString &&
          !aData->PropertyIsSet(eCSSProperty_font_style)) {
        nsAutoString str(value->GetStringValue());
        str.CompressWhitespace();
        if (str.EqualsASCII("normal")) {
          aData->SetKeywordValue(eCSSProperty_font_style,
                                 NS_STYLE_FONT_STYLE_NORMAL);
        } else if (str.EqualsASCII("italic")) {
          aData->SetKeywordValue(eCSSProperty_font_style,
                                 NS_STYLE_FONT_STYLE_ITALIC);
        }
      }
    }

    // fontweight
    //
    // "Specified the font weight for the token. Deprecated in favor of
    // mathvariant."
    //
    // values: "normal" | "bold"
    // default: normal
    //
    // Note that the font-weight property is reset in layout/style/ when
    // -moz-math-variant is specified.
    value = aAttributes->GetAttr(nsGkAtoms::fontweight_);
    if (value) {
      WarnDeprecated(nsGkAtoms::fontweight_->GetUTF16String(),
                     nsGkAtoms::mathvariant_->GetUTF16String(),
                     aData->Document());
      if (value->Type() == nsAttrValue::eString &&
          !aData->PropertyIsSet(eCSSProperty_font_weight)) {
        nsAutoString str(value->GetStringValue());
        str.CompressWhitespace();
        if (str.EqualsASCII("normal")) {
          aData->SetKeywordValue(eCSSProperty_font_weight,
                                 NS_STYLE_FONT_WEIGHT_NORMAL);
        } else if (str.EqualsASCII("bold")) {
          aData->SetKeywordValue(eCSSProperty_font_weight,
                                 NS_STYLE_FONT_WEIGHT_BOLD);
        }
      }
    }

    // mathvariant
    //
    // "Specifies the logical class of the token. Note that this class is more
    // than styling, it typically conveys semantic intent;"
    //
    // values: "normal" | "bold" | "italic" | "bold-italic" | "double-struck" |
    // "bold-fraktur" | "script" | "bold-script" | "fraktur" | "sans-serif" |
    // "bold-sans-serif" | "sans-serif-italic" | "sans-serif-bold-italic" |
    // "monospace" | "initial" | "tailed" | "looped" | "stretched"
    // default: normal (except on <mi>)
    //
    value = aAttributes->GetAttr(nsGkAtoms::mathvariant_);
    if (value && value->Type() == nsAttrValue::eString &&
        !aData->PropertyIsSet(eCSSProperty__moz_math_variant)) {
      nsAutoString str(value->GetStringValue());
      str.CompressWhitespace();
      static const char sizes[19][23] = {"normal",
                                         "bold",
                                         "italic",
                                         "bold-italic",
                                         "script",
                                         "bold-script",
                                         "fraktur",
                                         "double-struck",
                                         "bold-fraktur",
                                         "sans-serif",
                                         "bold-sans-serif",
                                         "sans-serif-italic",
                                         "sans-serif-bold-italic",
                                         "monospace",
                                         "initial",
                                         "tailed",
                                         "looped",
                                         "stretched"};
      static const int32_t values[MOZ_ARRAY_LENGTH(sizes)] = {
          NS_MATHML_MATHVARIANT_NORMAL,
          NS_MATHML_MATHVARIANT_BOLD,
          NS_MATHML_MATHVARIANT_ITALIC,
          NS_MATHML_MATHVARIANT_BOLD_ITALIC,
          NS_MATHML_MATHVARIANT_SCRIPT,
          NS_MATHML_MATHVARIANT_BOLD_SCRIPT,
          NS_MATHML_MATHVARIANT_FRAKTUR,
          NS_MATHML_MATHVARIANT_DOUBLE_STRUCK,
          NS_MATHML_MATHVARIANT_BOLD_FRAKTUR,
          NS_MATHML_MATHVARIANT_SANS_SERIF,
          NS_MATHML_MATHVARIANT_BOLD_SANS_SERIF,
          NS_MATHML_MATHVARIANT_SANS_SERIF_ITALIC,
          NS_MATHML_MATHVARIANT_SANS_SERIF_BOLD_ITALIC,
          NS_MATHML_MATHVARIANT_MONOSPACE,
          NS_MATHML_MATHVARIANT_INITIAL,
          NS_MATHML_MATHVARIANT_TAILED,
          NS_MATHML_MATHVARIANT_LOOPED,
          NS_MATHML_MATHVARIANT_STRETCHED};
      for (uint32_t i = 0; i < ArrayLength(sizes); ++i) {
        if (str.EqualsASCII(sizes[i])) {
          aData->SetKeywordValue(eCSSProperty__moz_math_variant, values[i]);
          break;
        }
      }
    }
  }

  // mathbackground
  //
  // "Specifies the background color to be used to fill in the bounding box of
  // the element and its children. The default, 'transparent', lets the
  // background color, if any, used in the current rendering context to show
  // through."
  //
  // values: color | "transparent"
  // default: "transparent"
  //
  // background
  //
  // "Specified the background color to be used to fill in the bounding box of
  // the element and its children. Deprecated in favor of mathbackground."
  //
  // values: color | "transparent"
  // default: "transparent"
  //
  if (aData->mSIDs & NS_STYLE_INHERIT_BIT(Background)) {
    const nsAttrValue* value = aAttributes->GetAttr(nsGkAtoms::mathbackground_);
    if (!value) {
      value = aAttributes->GetAttr(nsGkAtoms::background);
      if (value) {
        WarnDeprecated(nsGkAtoms::background->GetUTF16String(),
                       nsGkAtoms::mathbackground_->GetUTF16String(),
                       aData->Document());
      }
    }
    if (value) {
      nscolor color;
      if (value->GetColorValue(color)) {
        aData->SetColorValueIfUnset(eCSSProperty_background_color, color);
      }
    }
  }

  // mathcolor
  //
  // "Specifies the foreground color to use when drawing the components of this
  // element, such as the content for token elements or any lines, surds, or
  // other decorations. It also establishes the default mathcolor used for
  // child elements when used on a layout element."
  //
  // values: color
  // default: inherited
  //
  // color
  //
  // "Specified the color for the token. Deprecated in favor of mathcolor."
  //
  // values: color
  // default: inherited
  //
  if (aData->mSIDs & NS_STYLE_INHERIT_BIT(Color)) {
    const nsAttrValue* value = aAttributes->GetAttr(nsGkAtoms::mathcolor_);
    if (!value) {
      value = aAttributes->GetAttr(nsGkAtoms::color);
      if (value) {
        WarnDeprecated(nsGkAtoms::color->GetUTF16String(),
                       nsGkAtoms::mathcolor_->GetUTF16String(),
                       aData->Document());
      }
    }
    nscolor color;
    if (value && value->GetColorValue(color)) {
      aData->SetColorValueIfUnset(eCSSProperty_color, color);
    }
  }

  if (aData->mSIDs & NS_STYLE_INHERIT_BIT(Position)) {
    // width
    //
    // "Specifies the desired width of the entire table and is intended for
    // visual user agents. When the value is a percentage value, the value is
    // relative to the horizontal space a MathML renderer has available for the
    // math element. When the value is "auto", the MathML renderer should
    // calculate the table width from its contents using whatever layout
    // algorithm it chooses. "
    //
    // values: "auto" | length
    // default: auto
    //
    if (!aData->PropertyIsSet(eCSSProperty_width)) {
      const nsAttrValue* value = aAttributes->GetAttr(nsGkAtoms::width);
      nsCSSValue width;
      // This does not handle auto and unitless values
      if (value && value->Type() == nsAttrValue::eString) {
        ParseNumericValue(value->GetStringValue(), width, 0, aData->Document());
        if (width.GetUnit() == eCSSUnit_Percent) {
          aData->SetPercentValue(eCSSProperty_width, width.GetPercentValue());
        } else if (width.GetUnit() != eCSSUnit_Null) {
          aData->SetLengthValue(eCSSProperty_width, width);
        }
      }
    }
  }

  // dir
  //
  // Overall Directionality of Mathematics Formulas:
  // "The overall directionality for a formula, basically the direction of the
  // Layout Schemata, is specified by the dir attribute on the containing math
  // element (see Section 2.2 The Top-Level math Element). The default is ltr.
  // [...] The overall directionality is usually set on the math, but may also
  // be switched for individual subformula by using the dir attribute on mrow
  // or mstyle elements."
  //
  // Bidirectional Layout in Token Elements:
  // "Specifies the initial directionality for text within the token:
  // ltr (Left To Right) or rtl (Right To Left). This attribute should only be
  // needed in rare cases involving weak or neutral characters;
  // see Section 3.1.5.1 Overall Directionality of Mathematics Formulas for
  // further discussion. It has no effect on mspace."
  //
  // values: "ltr" | "rtl"
  // default: inherited
  //
  if (aData->mSIDs & NS_STYLE_INHERIT_BIT(Visibility)) {
    const nsAttrValue* value = aAttributes->GetAttr(nsGkAtoms::dir);
    if (value && value->Type() == nsAttrValue::eString &&
        !aData->PropertyIsSet(eCSSProperty_direction)) {
      nsAutoString str(value->GetStringValue());
      static const char dirs[][4] = {"ltr", "rtl"};
      static const int32_t dirValues[MOZ_ARRAY_LENGTH(dirs)] = {
          NS_STYLE_DIRECTION_LTR, NS_STYLE_DIRECTION_RTL};
      for (uint32_t i = 0; i < ArrayLength(dirs); ++i) {
        if (str.EqualsASCII(dirs[i])) {
          aData->SetKeywordValue(eCSSProperty_direction, dirValues[i]);
          break;
        }
      }
    }
  }
}

nsresult nsMathMLElement::GetEventTargetParent(EventChainPreVisitor& aVisitor) {
  nsresult rv = Element::GetEventTargetParent(aVisitor);
  NS_ENSURE_SUCCESS(rv, rv);

  return GetEventTargetParentForLinks(aVisitor);
}

nsresult nsMathMLElement::PostHandleEvent(EventChainPostVisitor& aVisitor) {
  return PostHandleEventForLinks(aVisitor);
}

NS_IMPL_ELEMENT_CLONE(nsMathMLElement)

EventStates nsMathMLElement::IntrinsicState() const {
  return Link::LinkState() | nsMathMLElementBase::IntrinsicState() |
         (mIncrementScriptLevel ? NS_EVENT_STATE_INCREMENT_SCRIPT_LEVEL
                                : EventStates());
}

bool nsMathMLElement::IsNodeOfType(uint32_t aFlags) const { return false; }

void nsMathMLElement::SetIncrementScriptLevel(bool aIncrementScriptLevel,
                                              bool aNotify) {
  if (aIncrementScriptLevel == mIncrementScriptLevel) return;
  mIncrementScriptLevel = aIncrementScriptLevel;

  NS_ASSERTION(aNotify, "We always notify!");

  UpdateState(true);
}

bool nsMathMLElement::IsFocusableInternal(int32_t* aTabIndex, bool aWithMouse) {
  nsCOMPtr<nsIURI> uri;
  if (IsLink(getter_AddRefs(uri))) {
    if (aTabIndex) {
      *aTabIndex = ((sTabFocusModel & eTabFocus_linksMask) == 0 ? -1 : 0);
    }
    return true;
  }

  if (aTabIndex) {
    *aTabIndex = -1;
  }

  return false;
}

bool nsMathMLElement::IsLink(nsIURI** aURI) const {
  // http://www.w3.org/TR/2010/REC-MathML3-20101021/chapter6.html#interf.link
  // The REC says that the following elements should not be linking elements:
  if (IsAnyOfMathMLElements(nsGkAtoms::mprescripts_, nsGkAtoms::none,
                            nsGkAtoms::malignmark_, nsGkAtoms::maligngroup_)) {
    *aURI = nullptr;
    return false;
  }

  bool hasHref = false;
  const nsAttrValue* href =
      mAttrsAndChildren.GetAttr(nsGkAtoms::href, kNameSpaceID_None);
  if (href) {
    // MathML href
    // The REC says: "When user agents encounter MathML elements with both href
    // and xlink:href attributes, the href attribute should take precedence."
    hasHref = true;
  } else {
    // To be a clickable XLink for styling and interaction purposes, we require:
    //
    //   xlink:href    - must be set
    //   xlink:type    - must be unset or set to "" or set to "simple"
    //   xlink:show    - must be unset or set to "", "new" or "replace"
    //   xlink:actuate - must be unset or set to "" or "onRequest"
    //
    // For any other values, we're either not a *clickable* XLink, or the end
    // result is poorly specified. Either way, we return false.

    static Element::AttrValuesArray sTypeVals[] = {&nsGkAtoms::_empty,
                                                   &nsGkAtoms::simple, nullptr};

    static Element::AttrValuesArray sShowVals[] = {
        &nsGkAtoms::_empty, &nsGkAtoms::_new, &nsGkAtoms::replace, nullptr};

    static Element::AttrValuesArray sActuateVals[] = {
        &nsGkAtoms::_empty, &nsGkAtoms::onRequest, nullptr};

    // Optimization: check for href first for early return
    href = mAttrsAndChildren.GetAttr(nsGkAtoms::href, kNameSpaceID_XLink);
    if (href &&
        FindAttrValueIn(kNameSpaceID_XLink, nsGkAtoms::type, sTypeVals,
                        eCaseMatters) != Element::ATTR_VALUE_NO_MATCH &&
        FindAttrValueIn(kNameSpaceID_XLink, nsGkAtoms::show, sShowVals,
                        eCaseMatters) != Element::ATTR_VALUE_NO_MATCH &&
        FindAttrValueIn(kNameSpaceID_XLink, nsGkAtoms::actuate, sActuateVals,
                        eCaseMatters) != Element::ATTR_VALUE_NO_MATCH) {
      hasHref = true;
    }
  }

  if (hasHref) {
    nsCOMPtr<nsIURI> baseURI = GetBaseURI();
    // Get absolute URI
    nsAutoString hrefStr;
    href->ToString(hrefStr);
    nsContentUtils::NewURIWithDocumentCharset(aURI, hrefStr, OwnerDoc(),
                                              baseURI);
    // must promise out param is non-null if we return true
    return !!*aURI;
  }

  *aURI = nullptr;
  return false;
}

void nsMathMLElement::GetLinkTarget(nsAString& aTarget) {
  const nsAttrValue* target =
      mAttrsAndChildren.GetAttr(nsGkAtoms::target, kNameSpaceID_XLink);
  if (target) {
    target->ToString(aTarget);
  }

  if (aTarget.IsEmpty()) {
    static Element::AttrValuesArray sShowVals[] = {
        &nsGkAtoms::_new, &nsGkAtoms::replace, nullptr};

    switch (FindAttrValueIn(kNameSpaceID_XLink, nsGkAtoms::show, sShowVals,
                            eCaseMatters)) {
      case 0:
        aTarget.AssignLiteral("_blank");
        return;
      case 1:
        return;
    }
    OwnerDoc()->GetBaseTarget(aTarget);
  }
}

already_AddRefed<nsIURI> nsMathMLElement::GetHrefURI() const {
  nsCOMPtr<nsIURI> hrefURI;
  return IsLink(getter_AddRefs(hrefURI)) ? hrefURI.forget() : nullptr;
}

nsresult nsMathMLElement::AfterSetAttr(int32_t aNameSpaceID, nsAtom* aName,
                                       const nsAttrValue* aValue,
                                       const nsAttrValue* aOldValue,
                                       nsIPrincipal* aSubjectPrincipal,
                                       bool aNotify) {
  // It is important that this be done after the attribute is set/unset.
  // We will need the updated attribute value because notifying the document
  // that content states have changed will call IntrinsicState, which will try
  // to get updated information about the visitedness from Link.
  if (aName == nsGkAtoms::href && (aNameSpaceID == kNameSpaceID_None ||
                                   aNameSpaceID == kNameSpaceID_XLink)) {
    if (aValue && aNameSpaceID == kNameSpaceID_XLink) {
      WarnDeprecated(u"xlink:href", u"href", OwnerDoc());
    }
    // Note: When unsetting href, there may still be another href since there
    // are 2 possible namespaces.
    Link::ResetLinkState(aNotify, aValue || Link::ElementHasHref());
  }

  return nsMathMLElementBase::AfterSetAttr(
      aNameSpaceID, aName, aValue, aOldValue, aSubjectPrincipal, aNotify);
}

JSObject* nsMathMLElement::WrapNode(JSContext* aCx,
                                    JS::Handle<JSObject*> aGivenProto) {
  return ElementBinding::Wrap(aCx, this, aGivenProto);
}