/* -*- 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 "mozilla/ArrayUtils.h"

#include "nsSVGLength2.h"

#include "mozilla/dom/SVGAnimatedLength.h"

#include "mozilla/dom/SVGViewportElement.h"

#include "nsContentUtils.h" // NS_ENSURE_FINITE

#include "nsIFrame.h"

#include "nsSMILFloatType.h"

#include "nsSMILValue.h"

#include "nsSVGAttrTearoffTable.h"

#include "nsSVGIntegrationUtils.h"

#include "nsTextFormatter.h"

#include "DOMSVGLength.h"

#include "LayoutLogging.h"

using namespace mozilla;

using namespace mozilla::dom;

static nsStaticAtom** const unitMap[] =

{

  nullptr, /* SVG_LENGTHTYPE_UNKNOWN */

  nullptr, /* SVG_LENGTHTYPE_NUMBER */

  &nsGkAtoms::percentage,

  &nsGkAtoms::em,

  &nsGkAtoms::ex,

  &nsGkAtoms::px,

  &nsGkAtoms::cm,

  &nsGkAtoms::mm,

  &nsGkAtoms::in,

  &nsGkAtoms::pt,

  &nsGkAtoms::pc

};

static nsSVGAttrTearoffTable<nsSVGLength2, SVGAnimatedLength>

  sSVGAnimatedLengthTearoffTable;

/* Helper functions */

static bool

IsValidUnitType(uint16_t unit)

{

  if (unit > SVGLength_Binding::SVG_LENGTHTYPE_UNKNOWN &&

      unit <= SVGLength_Binding::SVG_LENGTHTYPE_PC)

    return true;

  return false;

}

static void

GetUnitString(nsAString& unit, uint16_t unitType)

{

  if (IsValidUnitType(unitType)) {

    if (unitMap[unitType]) {

      (*unitMap[unitType])->ToString(unit);

    }

    return;

  }

  MOZ_ASSERT_UNREACHABLE("Unknown unit type");

}

static uint16_t

GetUnitTypeForString(const nsAString& unitStr)

{

  if (unitStr.IsEmpty())

    return SVGLength_Binding::SVG_LENGTHTYPE_NUMBER;

  nsAtom *unitAtom = NS_GetStaticAtom(unitStr);

  if (unitAtom) {

    for (uint32_t i = 0 ; i < ArrayLength(unitMap) ; i++) {

      if (unitMap[i] && *unitMap[i] == unitAtom) {

        return i;

      }

    }

  }

  return SVGLength_Binding::SVG_LENGTHTYPE_UNKNOWN;

}

static void

GetValueString(nsAString &aValueAsString, float aValue, uint16_t aUnitType)

{

  nsTextFormatter::ssprintf(aValueAsString, u"%g", (double)aValue);

  nsAutoString unitString;

  GetUnitString(unitString, aUnitType);

  aValueAsString.Append(unitString);

}

static bool

GetValueFromString(const nsAString& aString,

                   float& aValue,

                   uint16_t* aUnitType)

{

  RangedPtr<const char16_t> iter =

    SVGContentUtils::GetStartRangedPtr(aString);

  const RangedPtr<const char16_t> end =

    SVGContentUtils::GetEndRangedPtr(aString);

  if (!SVGContentUtils::ParseNumber(iter, end, aValue)) {

    return false;

  }

  const nsAString& units = Substring(iter.get(), end.get());

  *aUnitType = GetUnitTypeForString(units);

  return IsValidUnitType(*aUnitType);

}

static float

FixAxisLength(float aLength)

{

  if (aLength == 0.0f) {

    LAYOUT_WARNING("zero axis length");

    return 1e-20f;

  }

  return aLength;

}

SVGElementMetrics::SVGElementMetrics(nsSVGElement* aSVGElement,

                                     SVGViewportElement* aCtx)

  : mSVGElement(aSVGElement)

  , mCtx(aCtx)

{

}

float

SVGElementMetrics::GetEmLength() const

{

  return SVGContentUtils::GetFontSize(mSVGElement);

}

float

SVGElementMetrics::GetExLength() const

{

  return SVGContentUtils::GetFontXHeight(mSVGElement);

}

float

SVGElementMetrics::GetAxisLength(uint8_t aCtxType) const

{

  if (!EnsureCtx()) {

    return 1;

  }

  return FixAxisLength(mCtx->GetLength(aCtxType));

}

bool

SVGElementMetrics::EnsureCtx() const

{

  if (!mCtx && mSVGElement) {

    mCtx = mSVGElement->GetCtx();

    if (!mCtx && mSVGElement->IsSVGElement(nsGkAtoms::svg)) {

      // mSVGElement must be the outer svg element

      mCtx = static_cast<SVGViewportElement*>(mSVGElement);

    }

  }

  return mCtx != nullptr;

}

NonSVGFrameUserSpaceMetrics::NonSVGFrameUserSpaceMetrics(nsIFrame* aFrame)

  : mFrame(aFrame)

{

}

float

NonSVGFrameUserSpaceMetrics::GetEmLength() const

{

  return SVGContentUtils::GetFontSize(mFrame);

}

float

NonSVGFrameUserSpaceMetrics::GetExLength() const

{

  return SVGContentUtils::GetFontXHeight(mFrame);

}

gfx::Size

NonSVGFrameUserSpaceMetrics::GetSize() const

{

  return nsSVGIntegrationUtils::GetSVGCoordContextForNonSVGFrame(mFrame);

}

float

UserSpaceMetricsWithSize::GetAxisLength(uint8_t aCtxType) const

{

  gfx::Size size = GetSize();

  float length;

  switch (aCtxType) {

  case SVGContentUtils::X:

    length = size.width;

    break;

  case SVGContentUtils::Y:

    length = size.height;

    break;

  case SVGContentUtils::XY:

    length = SVGContentUtils::ComputeNormalizedHypotenuse(size.width, size.height);

    break;

  default:

    MOZ_ASSERT_UNREACHABLE("Unknown axis type");

    length = 1;

    break;

  }

  return FixAxisLength(length);

}

float

nsSVGLength2::GetPixelsPerUnit(nsSVGElement* aSVGElement,

                               uint8_t aUnitType) const

{

  return GetPixelsPerUnit(SVGElementMetrics(aSVGElement), aUnitType);

}

float

nsSVGLength2::GetPixelsPerUnit(SVGViewportElement* aCtx,

                               uint8_t aUnitType) const

{

  return GetPixelsPerUnit(SVGElementMetrics(aCtx, aCtx), aUnitType);

}

float

nsSVGLength2::GetPixelsPerUnit(nsIFrame* aFrame,

                               uint8_t aUnitType) const

{

  nsIContent* content = aFrame->GetContent();

  if (content->IsSVGElement()) {

    return GetPixelsPerUnit(

             SVGElementMetrics(static_cast<nsSVGElement*>(content)), aUnitType);

  }

  return GetPixelsPerUnit(NonSVGFrameUserSpaceMetrics(aFrame), aUnitType);

}

// See https://www.w3.org/TR/css-values-3/#absolute-lengths

static const float DPI = 96.0f;

float

nsSVGLength2::GetPixelsPerUnit(const UserSpaceMetrics& aMetrics,

                               uint8_t aUnitType) const

{

  switch (aUnitType) {

  case SVGLength_Binding::SVG_LENGTHTYPE_NUMBER:

  case SVGLength_Binding::SVG_LENGTHTYPE_PX:

    return 1;

  case SVGLength_Binding::SVG_LENGTHTYPE_MM:

    return DPI / MM_PER_INCH_FLOAT;

  case SVGLength_Binding::SVG_LENGTHTYPE_CM:

    return 10.0f * DPI / MM_PER_INCH_FLOAT;

  case SVGLength_Binding::SVG_LENGTHTYPE_IN:

    return DPI;

  case SVGLength_Binding::SVG_LENGTHTYPE_PT:

    return DPI / POINTS_PER_INCH_FLOAT;

  case SVGLength_Binding::SVG_LENGTHTYPE_PC:

    return 12.0f * DPI / POINTS_PER_INCH_FLOAT;

  case SVGLength_Binding::SVG_LENGTHTYPE_PERCENTAGE:

    return aMetrics.GetAxisLength(mCtxType) / 100.0f;

  case SVGLength_Binding::SVG_LENGTHTYPE_EMS:

    return aMetrics.GetEmLength();

  case SVGLength_Binding::SVG_LENGTHTYPE_EXS:

    return aMetrics.GetExLength();

  default:

    MOZ_ASSERT_UNREACHABLE("Unknown unit type");

    return 0;

  }

}

void

nsSVGLength2::SetBaseValueInSpecifiedUnits(float aValue,

                                           nsSVGElement *aSVGElement,

                                           bool aDoSetAttr)

{

  if (mIsBaseSet && mBaseVal == aValue) {

    return;

  }

  nsAttrValue emptyOrOldValue;

  if (aDoSetAttr) {

    emptyOrOldValue = aSVGElement->WillChangeLength(mAttrEnum);

  }

  mBaseVal = aValue;

  mIsBaseSet = true;

  if (!mIsAnimated) {

    mAnimVal = mBaseVal;

  }

  else {

    aSVGElement->AnimationNeedsResample();

  }

  if (aDoSetAttr) {

    aSVGElement->DidChangeLength(mAttrEnum, emptyOrOldValue);

  }

}

nsresult

nsSVGLength2::ConvertToSpecifiedUnits(uint16_t unitType,

                                      nsSVGElement *aSVGElement)

{

  if (!IsValidUnitType(unitType))

    return NS_ERROR_DOM_NOT_SUPPORTED_ERR;

  if (mIsBaseSet && mSpecifiedUnitType == uint8_t(unitType))

    return NS_OK;

  float pixelsPerUnit = GetPixelsPerUnit(aSVGElement, unitType);

  if (pixelsPerUnit == 0.0f) {

    return NS_ERROR_ILLEGAL_VALUE;

  }

  float valueInUserUnits =

    mBaseVal * GetPixelsPerUnit(aSVGElement, mSpecifiedUnitType);

  float valueInSpecifiedUnits = valueInUserUnits / pixelsPerUnit;

  if (!IsFinite(valueInSpecifiedUnits)) {

    return NS_ERROR_ILLEGAL_VALUE;

  }

  // Even though we're not changing the visual effect this length will have

  // on the document, we still need to send out notifications in case we have

  // mutation listeners, since the actual string value of the attribute will

  // change.

  nsAttrValue emptyOrOldValue = aSVGElement->WillChangeLength(mAttrEnum);

  mSpecifiedUnitType = uint8_t(unitType);

  // Setting aDoSetAttr to false here will ensure we don't call

  // Will/DidChangeAngle a second time (and dispatch duplicate notifications).

  SetBaseValueInSpecifiedUnits(valueInSpecifiedUnits, aSVGElement, false);

  aSVGElement->DidChangeLength(mAttrEnum, emptyOrOldValue);

  return NS_OK;

}

nsresult

nsSVGLength2::NewValueSpecifiedUnits(uint16_t unitType,

                                     float valueInSpecifiedUnits,

                                     nsSVGElement *aSVGElement)

{

  NS_ENSURE_FINITE(valueInSpecifiedUnits, NS_ERROR_ILLEGAL_VALUE);

  if (!IsValidUnitType(unitType))

    return NS_ERROR_DOM_NOT_SUPPORTED_ERR;

  if (mIsBaseSet && mBaseVal == valueInSpecifiedUnits &&

      mSpecifiedUnitType == uint8_t(unitType)) {

    return NS_OK;

  }

  nsAttrValue emptyOrOldValue = aSVGElement->WillChangeLength(mAttrEnum);

  mBaseVal = valueInSpecifiedUnits;

  mIsBaseSet = true;

  mSpecifiedUnitType = uint8_t(unitType);

  if (!mIsAnimated) {

    mAnimVal = mBaseVal;

  }

  else {

    aSVGElement->AnimationNeedsResample();

  }

  aSVGElement->DidChangeLength(mAttrEnum, emptyOrOldValue);

  return NS_OK;

}

nsresult

nsSVGLength2::ToDOMBaseVal(DOMSVGLength **aResult, nsSVGElement *aSVGElement)

{

  RefPtr<DOMSVGLength> domBaseVal =

    DOMSVGLength::GetTearOff(this, aSVGElement, false);

  domBaseVal.forget(aResult);

  return NS_OK;

}

nsresult

nsSVGLength2::ToDOMAnimVal(DOMSVGLength **aResult, nsSVGElement *aSVGElement)

{

  RefPtr<DOMSVGLength> domAnimVal =

    DOMSVGLength::GetTearOff(this, aSVGElement, true);

  domAnimVal.forget(aResult);

  return NS_OK;

}

/* Implementation */

nsresult

nsSVGLength2::SetBaseValueString(const nsAString &aValueAsString,

                                 nsSVGElement *aSVGElement,

                                 bool aDoSetAttr)

{

  float value;

  uint16_t unitType;

  if (!GetValueFromString(aValueAsString, value, &unitType)) {

    return NS_ERROR_DOM_SYNTAX_ERR;

  }

  if (mIsBaseSet && mBaseVal == float(value) &&

      mSpecifiedUnitType == uint8_t(unitType)) {

    return NS_OK;

  }

  nsAttrValue emptyOrOldValue;

  if (aDoSetAttr) {

    emptyOrOldValue = aSVGElement->WillChangeLength(mAttrEnum);

  }

  mBaseVal = value;

  mIsBaseSet = true;

  mSpecifiedUnitType = uint8_t(unitType);

  if (!mIsAnimated) {

    mAnimVal = mBaseVal;

  }

  else {

    aSVGElement->AnimationNeedsResample();

  }

  if (aDoSetAttr) {

    aSVGElement->DidChangeLength(mAttrEnum, emptyOrOldValue);

  }

  return NS_OK;

}

void

nsSVGLength2::GetBaseValueString(nsAString & aValueAsString) const

{

  GetValueString(aValueAsString, mBaseVal, mSpecifiedUnitType);

}

void

nsSVGLength2::GetAnimValueString(nsAString & aValueAsString) const

{

  GetValueString(aValueAsString, mAnimVal, mSpecifiedUnitType);

}

nsresult

nsSVGLength2::SetBaseValue(float aValue, nsSVGElement *aSVGElement,

                           bool aDoSetAttr)

{

  float pixelsPerUnit = GetPixelsPerUnit(aSVGElement, mSpecifiedUnitType);

  if (pixelsPerUnit == 0.0f) {

    return NS_ERROR_ILLEGAL_VALUE;

  }

  float valueInSpecifiedUnits = aValue / pixelsPerUnit;

  if (!IsFinite(valueInSpecifiedUnits)) {

    return NS_ERROR_ILLEGAL_VALUE;

  }

  SetBaseValueInSpecifiedUnits(valueInSpecifiedUnits,

                               aSVGElement, aDoSetAttr);

  return NS_OK;

}

void

nsSVGLength2::SetAnimValueInSpecifiedUnits(float aValue,

                                           nsSVGElement* aSVGElement)

{

  if (mAnimVal == aValue && mIsAnimated) {

    return;

  }

  mAnimVal = aValue;

  mIsAnimated = true;

  aSVGElement->DidAnimateLength(mAttrEnum);

}

nsresult

nsSVGLength2::SetAnimValue(float aValue, nsSVGElement *aSVGElement)

{

  float valueInSpecifiedUnits = aValue /

          GetPixelsPerUnit(aSVGElement, mSpecifiedUnitType);

  if (IsFinite(valueInSpecifiedUnits)) {

    SetAnimValueInSpecifiedUnits(valueInSpecifiedUnits, aSVGElement);

    return NS_OK;

  }

  return NS_ERROR_ILLEGAL_VALUE;

}

already_AddRefed<SVGAnimatedLength>

nsSVGLength2::ToDOMAnimatedLength(nsSVGElement* aSVGElement)

{

  RefPtr<SVGAnimatedLength> svgAnimatedLength =

    sSVGAnimatedLengthTearoffTable.GetTearoff(this);

  if (!svgAnimatedLength) {

    svgAnimatedLength = new SVGAnimatedLength(this, aSVGElement);

    sSVGAnimatedLengthTearoffTable.AddTearoff(this, svgAnimatedLength);

  }

  return svgAnimatedLength.forget();

}

SVGAnimatedLength::~SVGAnimatedLength()

{

  sSVGAnimatedLengthTearoffTable.RemoveTearoff(mVal);

}

UniquePtr<nsISMILAttr>

nsSVGLength2::ToSMILAttr(nsSVGElement *aSVGElement)

{

  return MakeUnique<SMILLength>(this, aSVGElement);

}

nsresult

nsSVGLength2::SMILLength::ValueFromString(const nsAString& aStr,

                                 const SVGAnimationElement* /*aSrcElement*/,

                                 nsSMILValue& aValue,

                                 bool& aPreventCachingOfSandwich) const

{

  float value;

  uint16_t unitType;

  if (!GetValueFromString(aStr, value, &unitType)) {

    return NS_ERROR_DOM_SYNTAX_ERR;

  }

  nsSMILValue val(nsSMILFloatType::Singleton());

  val.mU.mDouble = value * mVal->GetPixelsPerUnit(mSVGElement, unitType);

  aValue = val;

  aPreventCachingOfSandwich =

              (unitType == SVGLength_Binding::SVG_LENGTHTYPE_PERCENTAGE ||

               unitType == SVGLength_Binding::SVG_LENGTHTYPE_EMS ||

               unitType == SVGLength_Binding::SVG_LENGTHTYPE_EXS);

  return NS_OK;

}

nsSMILValue

nsSVGLength2::SMILLength::GetBaseValue() const

{

  nsSMILValue val(nsSMILFloatType::Singleton());

  val.mU.mDouble = mVal->GetBaseValue(mSVGElement);

  return val;

}

void

nsSVGLength2::SMILLength::ClearAnimValue()

{

  if (mVal->mIsAnimated) {

    mVal->mIsAnimated = false;

    mVal->mAnimVal = mVal->mBaseVal;

    mSVGElement->DidAnimateLength(mVal->mAttrEnum);

  }

}

nsresult

nsSVGLength2::SMILLength::SetAnimValue(const nsSMILValue& aValue)

{

  NS_ASSERTION(aValue.mType == nsSMILFloatType::Singleton(),

    "Unexpected type to assign animated value");

  if (aValue.mType == nsSMILFloatType::Singleton()) {

    return mVal->SetAnimValue(float(aValue.mU.mDouble), mSVGElement);

  }

  return NS_OK;

}