gecko-dev/dom/svg/SVGAnimatedNumber.cpp

/* -*- 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 "SVGAnimatedNumber.h"

#include "mozilla/Attributes.h"
#include "mozilla/SMILValue.h"
#include "mozilla/SVGContentUtils.h"
#include "nsContentUtils.h"
#include "SMILFloatType.h"
#include "SVGAttrTearoffTable.h"

using namespace mozilla::dom;

namespace mozilla {

/* Implementation */

//----------------------------------------------------------------------
// Helper class: AutoChangeNumberNotifier
// Stack-based helper class to ensure DidChangeNumber is called.
class MOZ_RAII AutoChangeNumberNotifier {
 public:
  AutoChangeNumberNotifier(SVGAnimatedNumber* aNumber, SVGElement* aSVGElement)
      : mNumber(aNumber), mSVGElement(aSVGElement) {
    MOZ_ASSERT(mNumber, "Expecting non-null number");
    MOZ_ASSERT(mSVGElement, "Expecting non-null element");
  }

  ~AutoChangeNumberNotifier() {
    mSVGElement->DidChangeNumber(mNumber->mAttrEnum);
    if (mNumber->mIsAnimated) {
      mSVGElement->AnimationNeedsResample();
    }
  }

 private:
  SVGAnimatedNumber* const mNumber;
  SVGElement* const mSVGElement;
};

static SVGAttrTearoffTable<SVGAnimatedNumber,
                           SVGAnimatedNumber::DOMAnimatedNumber>
    sSVGAnimatedNumberTearoffTable;

static bool GetValueFromString(const nsAString& aString,
                               bool aPercentagesAllowed, float& aValue) {
  bool success;
  auto token = SVGContentUtils::GetAndEnsureOneToken(aString, success);

  if (!success) {
    return false;
  }

  RangedPtr<const char16_t> iter = SVGContentUtils::GetStartRangedPtr(token);
  const RangedPtr<const char16_t> end = SVGContentUtils::GetEndRangedPtr(token);

  if (!SVGContentUtils::ParseNumber(iter, end, aValue)) {
    return false;
  }

  if (aPercentagesAllowed) {
    const nsAString& units = Substring(iter.get(), end.get());
    if (units.EqualsLiteral("%")) {
      aValue /= 100;
      return true;
    }
  }

  return iter == end;
}

nsresult SVGAnimatedNumber::SetBaseValueString(const nsAString& aValueAsString,
                                               SVGElement* aSVGElement) {
  float val;

  if (!GetValueFromString(aValueAsString,
                          aSVGElement->NumberAttrAllowsPercentage(mAttrEnum),
                          val)) {
    return NS_ERROR_DOM_SYNTAX_ERR;
  }

  mBaseVal = val;
  mIsBaseSet = true;
  if (!mIsAnimated) {
    mAnimVal = mBaseVal;
  } else {
    aSVGElement->AnimationNeedsResample();
  }

  // We don't need to call DidChange* here - we're only called by
  // SVGElement::ParseAttribute under Element::SetAttr,
  // which takes care of notifying.
  return NS_OK;
}

void SVGAnimatedNumber::GetBaseValueString(nsAString& aValueAsString) {
  aValueAsString.Truncate();
  aValueAsString.AppendFloat(mBaseVal);
}

void SVGAnimatedNumber::SetBaseValue(float aValue, SVGElement* aSVGElement) {
  if (mIsBaseSet && aValue == mBaseVal) {
    return;
  }

  AutoChangeNumberNotifier notifier(this, aSVGElement);

  mBaseVal = aValue;
  mIsBaseSet = true;
  if (!mIsAnimated) {
    mAnimVal = mBaseVal;
  }
}

void SVGAnimatedNumber::SetAnimValue(float aValue, SVGElement* aSVGElement) {
  if (mIsAnimated && aValue == mAnimVal) {
    return;
  }
  mAnimVal = aValue;
  mIsAnimated = true;
  aSVGElement->DidAnimateNumber(mAttrEnum);
}

already_AddRefed<DOMSVGAnimatedNumber> SVGAnimatedNumber::ToDOMAnimatedNumber(
    SVGElement* aSVGElement) {
  RefPtr<DOMAnimatedNumber> domAnimatedNumber =
      sSVGAnimatedNumberTearoffTable.GetTearoff(this);
  if (!domAnimatedNumber) {
    domAnimatedNumber = new DOMAnimatedNumber(this, aSVGElement);
    sSVGAnimatedNumberTearoffTable.AddTearoff(this, domAnimatedNumber);
  }

  return domAnimatedNumber.forget();
}

SVGAnimatedNumber::DOMAnimatedNumber::~DOMAnimatedNumber() {
  sSVGAnimatedNumberTearoffTable.RemoveTearoff(mVal);
}

UniquePtr<SMILAttr> SVGAnimatedNumber::ToSMILAttr(SVGElement* aSVGElement) {
  return MakeUnique<SMILNumber>(this, aSVGElement);
}

nsresult SVGAnimatedNumber::SMILNumber::ValueFromString(
    const nsAString& aStr,
    const mozilla::dom::SVGAnimationElement* /*aSrcElement*/, SMILValue& aValue,
    bool& aPreventCachingOfSandwich) const {
  float value;

  if (!GetValueFromString(
          aStr, mSVGElement->NumberAttrAllowsPercentage(mVal->mAttrEnum),
          value)) {
    return NS_ERROR_DOM_SYNTAX_ERR;
  }

  SMILValue val(SMILFloatType::Singleton());
  val.mU.mDouble = value;
  aValue = val;
  aPreventCachingOfSandwich = false;

  return NS_OK;
}

SMILValue SVGAnimatedNumber::SMILNumber::GetBaseValue() const {
  SMILValue val(SMILFloatType::Singleton());
  val.mU.mDouble = mVal->mBaseVal;
  return val;
}

void SVGAnimatedNumber::SMILNumber::ClearAnimValue() {
  if (mVal->mIsAnimated) {
    mVal->mIsAnimated = false;
    mVal->mAnimVal = mVal->mBaseVal;
    mSVGElement->DidAnimateNumber(mVal->mAttrEnum);
  }
}

nsresult SVGAnimatedNumber::SMILNumber::SetAnimValue(const SMILValue& aValue) {
  NS_ASSERTION(aValue.mType == SMILFloatType::Singleton(),
               "Unexpected type to assign animated value");
  if (aValue.mType == SMILFloatType::Singleton()) {
    mVal->SetAnimValue(float(aValue.mU.mDouble), mSVGElement);
  }
  return NS_OK;
}

}  // namespace mozilla