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/*
* Copyright (C) 2000 Lars Knoll (knoll@kde.org)
* Copyright (C) 2003-2017 Apple Inc. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*
*/
#pragma once
#include "BidiContext.h"
#include "BidiRunList.h"
#include "WritingMode.h"
#include <wtf/HashMap.h>
#include <wtf/Noncopyable.h>
#include <wtf/Vector.h>
namespace WebCore {
class RenderObject;
template<typename Iterator> class WhitespaceCollapsingState {
public:
void reset()
{
m_transitions.clear();
m_currentTransition = 0;
}
void startIgnoringSpaces(const Iterator& transition)
{
ASSERT(!(m_transitions.size() % 2));
m_transitions.append(transition);
}
void stopIgnoringSpaces(const Iterator& transition)
{
ASSERT(m_transitions.size() % 2);
m_transitions.append(transition);
}
// When ignoring spaces, this needs to be called for objects that need line boxes such as RenderInlines or
// hard line breaks to ensure that they're not ignored.
void ensureLineBoxInsideIgnoredSpaces(RenderObject& renderer)
{
Iterator transition(0, &renderer, 0);
stopIgnoringSpaces(transition);
startIgnoringSpaces(transition);
}
void decrementTransitionAt(size_t index)
{
m_transitions[index].fastDecrement();
}
const Vector<Iterator>& transitions() { return m_transitions; }
size_t numTransitions() const { return m_transitions.size(); }
size_t currentTransition() const { return m_currentTransition; }
void setCurrentTransition(size_t currentTransition) { m_currentTransition = currentTransition; }
void incrementCurrentTransition() { ++m_currentTransition; }
void decrementNumTransitions() { m_transitions.shrink(m_transitions.size() - 1); }
bool betweenTransitions() const { return m_currentTransition % 2; }
private:
Vector<Iterator> m_transitions;
size_t m_currentTransition { 0 };
};
// The BidiStatus at a given position (typically the end of a line) can
// be cached and then used to restart bidi resolution at that position.
struct BidiStatus {
BidiStatus() = default;
// Creates a BidiStatus representing a new paragraph root with a default direction.
// Uses TextDirection as it only has two possibilities instead of UCharDirection which has at least 19.
BidiStatus(TextDirection direction, bool isOverride)
: eor(direction == TextDirection::LTR ? U_LEFT_TO_RIGHT : U_RIGHT_TO_LEFT)
, lastStrong(eor)
, last(eor)
, context(BidiContext::create(direction == TextDirection::LTR ? 0 : 1, eor, isOverride))
{
}
BidiStatus(UCharDirection eor, UCharDirection lastStrong, UCharDirection last, RefPtr<BidiContext>&& context)
: eor(eor)
, lastStrong(lastStrong)
, last(last)
, context(WTFMove(context))
{
}
UCharDirection eor { U_OTHER_NEUTRAL };
UCharDirection lastStrong { U_OTHER_NEUTRAL };
UCharDirection last { U_OTHER_NEUTRAL };
RefPtr<BidiContext> context;
};
struct BidiEmbedding {
BidiEmbedding(UCharDirection direction, BidiEmbeddingSource source)
: direction(direction)
, source(source)
{
}
UCharDirection direction;
BidiEmbeddingSource source;
};
inline bool operator==(const BidiStatus& status1, const BidiStatus& status2)
{
return status1.eor == status2.eor && status1.last == status2.last && status1.lastStrong == status2.lastStrong && *(status1.context) == *(status2.context);
}
inline bool operator!=(const BidiStatus& status1, const BidiStatus& status2)
{
return !(status1 == status2);
}
struct BidiCharacterRun {
WTF_MAKE_FAST_ALLOCATED;
public:
BidiCharacterRun(unsigned start, unsigned stop, BidiContext* context, UCharDirection direction)
: m_start(start)
, m_stop(stop)
, m_override(context->override())
{
if (direction == U_OTHER_NEUTRAL)
direction = context->dir();
m_level = context->level();
// add level of run (cases I1 & I2)
if (m_level % 2) {
if (direction == U_LEFT_TO_RIGHT || direction == U_ARABIC_NUMBER || direction == U_EUROPEAN_NUMBER)
m_level++;
} else {
if (direction == U_RIGHT_TO_LEFT)
m_level++;
else if (direction == U_ARABIC_NUMBER || direction == U_EUROPEAN_NUMBER)
m_level += 2;
}
}
~BidiCharacterRun()
{
// Delete the linked list in a loop to prevent destructor recursion.
auto next = WTFMove(m_next);
while (next)
next = WTFMove(next->m_next);
}
unsigned start() const { return m_start; }
unsigned stop() const { return m_stop; }
unsigned char level() const { return m_level; }
bool reversed(bool visuallyOrdered) { return m_level % 2 && !visuallyOrdered; }
bool dirOverride(bool visuallyOrdered) { return m_override || visuallyOrdered; }
BidiCharacterRun* next() const { return m_next.get(); }
std::unique_ptr<BidiCharacterRun> takeNext() { return WTFMove(m_next); }
void setNext(std::unique_ptr<BidiCharacterRun>&& next) { m_next = WTFMove(next); }
private:
std::unique_ptr<BidiCharacterRun> m_next;
public:
unsigned m_start;
unsigned m_stop;
unsigned char m_level;
bool m_override : 1;
bool m_hasHyphen : 1; // Used by BidiRun subclass which is a layering violation but enables us to save 8 bytes per object on 64-bit.
};
enum VisualDirectionOverride {
NoVisualOverride,
VisualLeftToRightOverride,
VisualRightToLeftOverride
};
// BidiResolver is WebKit's implementation of the Unicode Bidi Algorithm
// http://unicode.org/reports/tr9
template<typename Iterator, typename Run, typename DerivedClass> class BidiResolverBase {
WTF_MAKE_NONCOPYABLE(BidiResolverBase);
public:
const Iterator& position() const { return m_current; }
void setPositionIgnoringNestedIsolates(const Iterator& position) { m_current = position; }
void setPosition(const Iterator& position, unsigned nestedIsolatedCount)
{
m_current = position;
m_nestedIsolateCount = nestedIsolatedCount;
}
void increment() { static_cast<DerivedClass&>(*this).incrementInternal(); }
BidiContext* context() const { return m_status.context.get(); }
void setContext(RefPtr<BidiContext>&& context) { m_status.context = WTFMove(context); }
void setLastDir(UCharDirection lastDir) { m_status.last = lastDir; }
void setLastStrongDir(UCharDirection lastStrongDir) { m_status.lastStrong = lastStrongDir; }
void setEorDir(UCharDirection eorDir) { m_status.eor = eorDir; }
UCharDirection dir() const { return m_direction; }
void setDir(UCharDirection direction) { m_direction = direction; }
const BidiStatus& status() const { return m_status; }
void setStatus(BidiStatus status) { m_status = status; }
WhitespaceCollapsingState<Iterator>& whitespaceCollapsingState() { return m_whitespaceCollapsingState; }
// The current algorithm handles nested isolates one layer of nesting at a time.
// But when we layout each isolated span, we will walk into (and ignore) all
// child isolated spans.
void enterIsolate() { m_nestedIsolateCount++; }
void exitIsolate() { ASSERT(m_nestedIsolateCount >= 1); m_nestedIsolateCount--; }
bool inIsolate() const { return m_nestedIsolateCount; }
void embed(UCharDirection, BidiEmbeddingSource);
bool commitExplicitEmbedding();
void createBidiRunsForLine(const Iterator& end, VisualDirectionOverride = NoVisualOverride, bool hardLineBreak = false);
BidiRunList<Run>& runs() { return m_runs; }
// FIXME: This used to be part of deleteRuns() but was a layering violation.
// It's unclear if this is still needed.
void markCurrentRunEmpty() { m_emptyRun = true; }
void setWhitespaceCollapsingTransitionForIsolatedRun(Run&, size_t);
unsigned whitespaceCollapsingTransitionForIsolatedRun(Run&);
protected:
BidiResolverBase() = default;
// FIXME: Instead of InlineBidiResolvers subclassing this method, we should
// pass in some sort of Traits object which knows how to create runs for appending.
void appendRun() { static_cast<DerivedClass&>(*this).appendRunInternal(); }
bool needsContinuePastEnd() const { return static_cast<const DerivedClass&>(*this).needsContinuePastEndInternal(); }
Iterator m_current;
// sor and eor are "start of run" and "end of run" respectively and correpond
// to abreviations used in UBA spec: http://unicode.org/reports/tr9/#BD7
Iterator m_sor; // Points to the first character in the current run.
Iterator m_eor; // Points to the last character in the current run.
Iterator m_last;
BidiStatus m_status;
UCharDirection m_direction { U_OTHER_NEUTRAL };
Iterator endOfLine;
bool m_reachedEndOfLine { false };
Iterator m_lastBeforeET; // Before a U_EUROPEAN_NUMBER_TERMINATOR
bool m_emptyRun { true };
// FIXME: This should not belong to the resolver, but rather be passed
// into createBidiRunsForLine by the caller.
BidiRunList<Run> m_runs;
WhitespaceCollapsingState<Iterator> m_whitespaceCollapsingState;
unsigned m_nestedIsolateCount { 0 };
HashMap<Run*, unsigned> m_whitespaceCollapsingTransitionForIsolatedRun;
private:
void raiseExplicitEmbeddingLevel(UCharDirection from, UCharDirection to);
void lowerExplicitEmbeddingLevel(UCharDirection from);
void checkDirectionInLowerRaiseEmbeddingLevel();
void updateStatusLastFromCurrentDirection(UCharDirection);
void reorderRunsFromLevels();
void incrementInternal() { m_current.increment(); }
void appendRunInternal();
bool needsContinuePastEndInternal() const { return true; }
Vector<BidiEmbedding, 8> m_currentExplicitEmbeddingSequence;
};
template<typename Iterator, typename Run>
class BidiResolver : public BidiResolverBase<Iterator, Run, BidiResolver<Iterator, Run>> {
};
template<typename Iterator, typename Run, typename IsolateRun>
class BidiResolverWithIsolate : public BidiResolverBase<Iterator, Run, BidiResolverWithIsolate<Iterator, Run, IsolateRun>> {
public:
~BidiResolverWithIsolate();
void incrementInternal();
void appendRunInternal();
bool needsContinuePastEndInternal() const;
Vector<IsolateRun>& isolatedRuns() { return m_isolatedRuns; }
private:
Vector<IsolateRun> m_isolatedRuns;
};
template<typename Iterator, typename Run, typename IsolateRun>
inline BidiResolverWithIsolate<Iterator, Run, IsolateRun>::~BidiResolverWithIsolate()
{
// The owner of this resolver should have handled the isolated runs.
ASSERT(m_isolatedRuns.isEmpty());
}
template<typename Iterator, typename Run, typename DerivedClass>
void BidiResolverBase<Iterator, Run, DerivedClass>::appendRunInternal()
{
if (!m_emptyRun && !m_eor.atEnd()) {
unsigned startOffset = m_sor.offset();
unsigned endOffset = m_eor.offset();
if (!endOfLine.atEnd() && endOffset >= endOfLine.offset()) {
m_reachedEndOfLine = true;
endOffset = endOfLine.offset();
}
if (endOffset >= startOffset)
m_runs.appendRun(makeUnique<Run>(startOffset, endOffset + 1, context(), m_direction));
m_eor.increment();
m_sor = m_eor;
}
m_direction = U_OTHER_NEUTRAL;
m_status.eor = U_OTHER_NEUTRAL;
}
template<typename Iterator, typename Run, typename DerivedClass>
void BidiResolverBase<Iterator, Run, DerivedClass>::embed(UCharDirection dir, BidiEmbeddingSource source)
{
// Isolated spans compute base directionality during their own UBA run.
// Do not insert fake embed characters once we enter an isolated span.
ASSERT(!inIsolate());
ASSERT(dir == U_POP_DIRECTIONAL_FORMAT || dir == U_LEFT_TO_RIGHT_EMBEDDING || dir == U_LEFT_TO_RIGHT_OVERRIDE || dir == U_RIGHT_TO_LEFT_EMBEDDING || dir == U_RIGHT_TO_LEFT_OVERRIDE);
m_currentExplicitEmbeddingSequence.append(BidiEmbedding(dir, source));
}
template<typename Iterator, typename Run, typename DerivedClass>
void BidiResolverBase<Iterator, Run, DerivedClass>::checkDirectionInLowerRaiseEmbeddingLevel()
{
ASSERT(m_status.eor != U_OTHER_NEUTRAL || m_eor.atEnd());
ASSERT(m_status.last != U_DIR_NON_SPACING_MARK
&& m_status.last != U_BOUNDARY_NEUTRAL
&& m_status.last != U_RIGHT_TO_LEFT_EMBEDDING
&& m_status.last != U_LEFT_TO_RIGHT_EMBEDDING
&& m_status.last != U_RIGHT_TO_LEFT_OVERRIDE
&& m_status.last != U_LEFT_TO_RIGHT_OVERRIDE
&& m_status.last != U_POP_DIRECTIONAL_FORMAT);
if (m_direction == U_OTHER_NEUTRAL)
m_direction = m_status.lastStrong == U_LEFT_TO_RIGHT ? U_LEFT_TO_RIGHT : U_RIGHT_TO_LEFT;
}
template<typename Iterator, typename Run, typename DerivedClass>
void BidiResolverBase<Iterator, Run, DerivedClass>::lowerExplicitEmbeddingLevel(UCharDirection from)
{
if (!m_emptyRun && m_eor != m_last) {
checkDirectionInLowerRaiseEmbeddingLevel();
// bidi.sor ... bidi.eor ... bidi.last eor; need to append the bidi.sor-bidi.eor run or extend it through bidi.last
if (from == U_LEFT_TO_RIGHT) {
// bidi.sor ... bidi.eor ... bidi.last L
if (m_status.eor == U_EUROPEAN_NUMBER) {
if (m_status.lastStrong != U_LEFT_TO_RIGHT) {
m_direction = U_EUROPEAN_NUMBER;
appendRun();
}
} else if (m_status.eor == U_ARABIC_NUMBER) {
m_direction = U_ARABIC_NUMBER;
appendRun();
} else if (m_status.lastStrong != U_LEFT_TO_RIGHT) {
appendRun();
m_direction = U_LEFT_TO_RIGHT;
}
} else if (m_status.eor == U_EUROPEAN_NUMBER || m_status.eor == U_ARABIC_NUMBER || m_status.lastStrong == U_LEFT_TO_RIGHT) {
appendRun();
m_direction = U_RIGHT_TO_LEFT;
}
m_eor = m_last;
}
appendRun();
m_emptyRun = true;
// sor for the new run is determined by the higher level (rule X10)
setLastDir(from);
setLastStrongDir(from);
m_eor = Iterator();
}
template<typename Iterator, typename Run, typename DerivedClass>
void BidiResolverBase<Iterator, Run, DerivedClass>::raiseExplicitEmbeddingLevel(UCharDirection from, UCharDirection to)
{
if (!m_emptyRun && m_eor != m_last) {
checkDirectionInLowerRaiseEmbeddingLevel();
// bidi.sor ... bidi.eor ... bidi.last eor; need to append the bidi.sor-bidi.eor run or extend it through bidi.last
if (to == U_LEFT_TO_RIGHT) {
// bidi.sor ... bidi.eor ... bidi.last L
if (m_status.eor == U_EUROPEAN_NUMBER) {
if (m_status.lastStrong != U_LEFT_TO_RIGHT) {
m_direction = U_EUROPEAN_NUMBER;
appendRun();
}
} else if (m_status.eor == U_ARABIC_NUMBER) {
m_direction = U_ARABIC_NUMBER;
appendRun();
} else if (m_status.lastStrong != U_LEFT_TO_RIGHT && from == U_LEFT_TO_RIGHT) {
appendRun();
m_direction = U_LEFT_TO_RIGHT;
}
} else if (m_status.eor == U_ARABIC_NUMBER
|| (m_status.eor == U_EUROPEAN_NUMBER && (m_status.lastStrong != U_LEFT_TO_RIGHT || from == U_RIGHT_TO_LEFT))
|| (m_status.eor != U_EUROPEAN_NUMBER && m_status.lastStrong == U_LEFT_TO_RIGHT && from == U_RIGHT_TO_LEFT)) {
appendRun();
m_direction = U_RIGHT_TO_LEFT;
}
m_eor = m_last;
}
appendRun();
m_emptyRun = true;
setLastDir(to);
setLastStrongDir(to);
m_eor = Iterator();
}
template<typename Iterator, typename Run, typename DerivedClass>
bool BidiResolverBase<Iterator, Run, DerivedClass>::commitExplicitEmbedding()
{
// When we're "inIsolate()" we're resolving the parent context which
// ignores (skips over) the isolated content, including embedding levels.
// We should never accrue embedding levels while skipping over isolated content.
ASSERT(!inIsolate() || m_currentExplicitEmbeddingSequence.isEmpty());
auto fromLevel = context()->level();
RefPtr<BidiContext> toContext = context();
for (auto& embedding : m_currentExplicitEmbeddingSequence) {
if (embedding.direction == U_POP_DIRECTIONAL_FORMAT) {
if (auto* parentContext = toContext->parent())
toContext = parentContext;
} else {
UCharDirection direction = (embedding.direction == U_RIGHT_TO_LEFT_EMBEDDING || embedding.direction == U_RIGHT_TO_LEFT_OVERRIDE) ? U_RIGHT_TO_LEFT : U_LEFT_TO_RIGHT;
bool override = embedding.direction == U_LEFT_TO_RIGHT_OVERRIDE || embedding.direction == U_RIGHT_TO_LEFT_OVERRIDE;
unsigned char level = toContext->level();
if (direction == U_RIGHT_TO_LEFT)
level = nextGreaterOddLevel(level);
else
level = nextGreaterEvenLevel(level);
if (level < 61)
toContext = BidiContext::create(level, direction, override, embedding.source, toContext.get());
}
}
auto toLevel = toContext->level();
if (toLevel > fromLevel)
raiseExplicitEmbeddingLevel(fromLevel % 2 ? U_RIGHT_TO_LEFT : U_LEFT_TO_RIGHT, toLevel % 2 ? U_RIGHT_TO_LEFT : U_LEFT_TO_RIGHT);
else if (toLevel < fromLevel)
lowerExplicitEmbeddingLevel(fromLevel % 2 ? U_RIGHT_TO_LEFT : U_LEFT_TO_RIGHT);
setContext(WTFMove(toContext));
m_currentExplicitEmbeddingSequence.clear();
return fromLevel != toLevel;
}
template<typename Iterator, typename Run, typename DerivedClass>
inline void BidiResolverBase<Iterator, Run, DerivedClass>::updateStatusLastFromCurrentDirection(UCharDirection dirCurrent)
{
switch (dirCurrent) {
case U_EUROPEAN_NUMBER_TERMINATOR:
if (m_status.last != U_EUROPEAN_NUMBER)
m_status.last = U_EUROPEAN_NUMBER_TERMINATOR;
break;
case U_EUROPEAN_NUMBER_SEPARATOR:
case U_COMMON_NUMBER_SEPARATOR:
case U_SEGMENT_SEPARATOR:
case U_WHITE_SPACE_NEUTRAL:
case U_OTHER_NEUTRAL:
switch (m_status.last) {
case U_LEFT_TO_RIGHT:
case U_RIGHT_TO_LEFT:
case U_RIGHT_TO_LEFT_ARABIC:
case U_EUROPEAN_NUMBER:
case U_ARABIC_NUMBER:
m_status.last = dirCurrent;
break;
default:
m_status.last = U_OTHER_NEUTRAL;
}
break;
case U_DIR_NON_SPACING_MARK:
case U_BOUNDARY_NEUTRAL:
case U_RIGHT_TO_LEFT_EMBEDDING:
case U_LEFT_TO_RIGHT_EMBEDDING:
case U_RIGHT_TO_LEFT_OVERRIDE:
case U_LEFT_TO_RIGHT_OVERRIDE:
case U_POP_DIRECTIONAL_FORMAT:
// ignore these
break;
case U_EUROPEAN_NUMBER:
FALLTHROUGH;
default:
m_status.last = dirCurrent;
}
}
template<typename Iterator, typename Run, typename DerivedClass>
inline void BidiResolverBase<Iterator, Run, DerivedClass>::reorderRunsFromLevels()
{
unsigned char levelLow = 128;
unsigned char levelHigh = 0;
for (Run* run = m_runs.firstRun(); run; run = run->next()) {
levelHigh = std::max(run->level(), levelHigh);
levelLow = std::min(run->level(), levelLow);
}
// This implements reordering of the line (L2 according to Bidi spec):
// http://unicode.org/reports/tr9/#L2
// L2. From the highest level found in the text to the lowest odd level on each line,
// reverse any contiguous sequence of characters that are at that level or higher.
// Reversing is only done up to the lowest odd level.
if (!(levelLow % 2))
levelLow++;
unsigned count = m_runs.runCount() - 1;
while (levelHigh >= levelLow) {
unsigned i = 0;
Run* run = m_runs.firstRun();
while (i < count) {
for (;i < count && run && run->level() < levelHigh; i++)
run = run->next();
unsigned start = i;
for (;i <= count && run && run->level() >= levelHigh; i++)
run = run->next();
unsigned end = i - 1;
m_runs.reverseRuns(start, end);
}
levelHigh--;
}
}
template<typename Iterator, typename Run, typename DerivedClass>
void BidiResolverBase<Iterator, Run, DerivedClass>::createBidiRunsForLine(const Iterator& end, VisualDirectionOverride override, bool hardLineBreak)
{
ASSERT(m_direction == U_OTHER_NEUTRAL);
if (override != NoVisualOverride) {
m_emptyRun = false;
m_sor = m_current;
m_eor = Iterator();
while (m_current != end && !m_current.atEnd()) {
m_eor = m_current;
increment();
}
m_direction = override == VisualLeftToRightOverride ? U_LEFT_TO_RIGHT : U_RIGHT_TO_LEFT;
appendRun();
m_runs.setLogicallyLastRun(m_runs.lastRun());
if (override == VisualRightToLeftOverride && m_runs.runCount())
m_runs.reverseRuns(0, m_runs.runCount() - 1);
return;
}
m_emptyRun = true;
m_eor = Iterator();
m_last = m_current;
bool pastEnd = false;
BidiResolverBase<Iterator, Run, DerivedClass> stateAtEnd;
while (true) {
UCharDirection dirCurrent;
if (pastEnd && (hardLineBreak || m_current.atEnd())) {
BidiContext* c = context();
if (hardLineBreak) {
// A deviation from the Unicode Bidi Algorithm in order to match
// WinIE and user expectations: hard line breaks reset bidi state
// coming from unicode bidi control characters, but not those from
// DOM nodes with specified directionality
stateAtEnd.setContext(c->copyStackRemovingUnicodeEmbeddingContexts());
dirCurrent = stateAtEnd.context()->dir();
stateAtEnd.setEorDir(dirCurrent);
stateAtEnd.setLastDir(dirCurrent);
stateAtEnd.setLastStrongDir(dirCurrent);
} else {
while (c->parent())
c = c->parent();
dirCurrent = c->dir();
}
} else {
dirCurrent = m_current.direction();
if (context()->override()
&& dirCurrent != U_RIGHT_TO_LEFT_EMBEDDING
&& dirCurrent != U_LEFT_TO_RIGHT_EMBEDDING
&& dirCurrent != U_RIGHT_TO_LEFT_OVERRIDE
&& dirCurrent != U_LEFT_TO_RIGHT_OVERRIDE
&& dirCurrent != U_POP_DIRECTIONAL_FORMAT)
dirCurrent = context()->dir();
else if (dirCurrent == U_DIR_NON_SPACING_MARK)
dirCurrent = m_status.last;
}
#if PLATFORM(WIN)
// Our Windows build hasn't updated its headers from ICU 6.1, which doesn't have these symbols.
const UCharDirection U_FIRST_STRONG_ISOLATE = static_cast<UCharDirection>(19);
const UCharDirection U_LEFT_TO_RIGHT_ISOLATE = static_cast<UCharDirection>(20);
const UCharDirection U_RIGHT_TO_LEFT_ISOLATE = static_cast<UCharDirection>(21);
const UCharDirection U_POP_DIRECTIONAL_ISOLATE = static_cast<UCharDirection>(22);
#endif
// We ignore all character directionality while in unicode-bidi: isolate spans.
// We'll handle ordering the isolated characters in a second pass.
if (inIsolate() || dirCurrent == U_FIRST_STRONG_ISOLATE || dirCurrent == U_LEFT_TO_RIGHT_ISOLATE || dirCurrent == U_RIGHT_TO_LEFT_ISOLATE || dirCurrent == U_POP_DIRECTIONAL_ISOLATE)
dirCurrent = U_OTHER_NEUTRAL;
ASSERT(m_status.eor != U_OTHER_NEUTRAL || m_eor.atEnd());
switch (dirCurrent) {
// embedding and overrides (X1-X9 in the Bidi specs)
case U_RIGHT_TO_LEFT_EMBEDDING:
case U_LEFT_TO_RIGHT_EMBEDDING:
case U_RIGHT_TO_LEFT_OVERRIDE:
case U_LEFT_TO_RIGHT_OVERRIDE:
case U_POP_DIRECTIONAL_FORMAT:
embed(dirCurrent, FromUnicode);
commitExplicitEmbedding();
break;
// strong types
case U_LEFT_TO_RIGHT:
switch(m_status.last) {
case U_RIGHT_TO_LEFT:
case U_RIGHT_TO_LEFT_ARABIC:
case U_EUROPEAN_NUMBER:
case U_ARABIC_NUMBER:
if (m_status.last != U_EUROPEAN_NUMBER || m_status.lastStrong != U_LEFT_TO_RIGHT)
appendRun();
break;
case U_LEFT_TO_RIGHT:
break;
case U_EUROPEAN_NUMBER_SEPARATOR:
case U_EUROPEAN_NUMBER_TERMINATOR:
case U_COMMON_NUMBER_SEPARATOR:
case U_BOUNDARY_NEUTRAL:
case U_BLOCK_SEPARATOR:
case U_SEGMENT_SEPARATOR:
case U_WHITE_SPACE_NEUTRAL:
case U_OTHER_NEUTRAL:
if (m_status.eor == U_EUROPEAN_NUMBER) {
if (m_status.lastStrong != U_LEFT_TO_RIGHT) {
// the numbers need to be on a higher embedding level, so let's close that run
m_direction = U_EUROPEAN_NUMBER;
appendRun();
if (context()->dir() != U_LEFT_TO_RIGHT) {
// the neutrals take the embedding direction, which is R
m_eor = m_last;
m_direction = U_RIGHT_TO_LEFT;
appendRun();
}
}
} else if (m_status.eor == U_ARABIC_NUMBER) {
// Arabic numbers are always on a higher embedding level, so let's close that run
m_direction = U_ARABIC_NUMBER;
appendRun();
if (context()->dir() != U_LEFT_TO_RIGHT) {
// the neutrals take the embedding direction, which is R
m_eor = m_last;
m_direction = U_RIGHT_TO_LEFT;
appendRun();
}
} else if (m_status.lastStrong != U_LEFT_TO_RIGHT) {
//last stuff takes embedding dir
if (context()->dir() == U_RIGHT_TO_LEFT) {
m_eor = m_last;
m_direction = U_RIGHT_TO_LEFT;
}
appendRun();
}
break;
default:
break;
}
m_eor = m_current;
m_status.eor = U_LEFT_TO_RIGHT;
m_status.lastStrong = U_LEFT_TO_RIGHT;
m_direction = U_LEFT_TO_RIGHT;
break;
case U_RIGHT_TO_LEFT_ARABIC:
case U_RIGHT_TO_LEFT:
switch (m_status.last) {
case U_LEFT_TO_RIGHT:
case U_EUROPEAN_NUMBER:
case U_ARABIC_NUMBER:
appendRun();
FALLTHROUGH;
case U_RIGHT_TO_LEFT:
case U_RIGHT_TO_LEFT_ARABIC:
break;
case U_EUROPEAN_NUMBER_SEPARATOR:
case U_EUROPEAN_NUMBER_TERMINATOR:
case U_COMMON_NUMBER_SEPARATOR:
case U_BOUNDARY_NEUTRAL:
case U_BLOCK_SEPARATOR:
case U_SEGMENT_SEPARATOR:
case U_WHITE_SPACE_NEUTRAL:
case U_OTHER_NEUTRAL:
if (m_status.eor == U_EUROPEAN_NUMBER) {
if (m_status.lastStrong == U_LEFT_TO_RIGHT && context()->dir() == U_LEFT_TO_RIGHT)
m_eor = m_last;
appendRun();
} else if (m_status.eor == U_ARABIC_NUMBER)
appendRun();
else if (m_status.lastStrong == U_LEFT_TO_RIGHT) {
if (context()->dir() == U_LEFT_TO_RIGHT)
m_eor = m_last;
appendRun();
}
break;
default:
break;
}
m_eor = m_current;
m_status.eor = U_RIGHT_TO_LEFT;
m_status.lastStrong = dirCurrent;
m_direction = U_RIGHT_TO_LEFT;
break;
// weak types:
case U_EUROPEAN_NUMBER:
if (m_status.lastStrong != U_RIGHT_TO_LEFT_ARABIC) {
// if last strong was AL change EN to AN
switch (m_status.last) {
case U_EUROPEAN_NUMBER:
case U_LEFT_TO_RIGHT:
break;
case U_RIGHT_TO_LEFT:
case U_RIGHT_TO_LEFT_ARABIC:
case U_ARABIC_NUMBER:
m_eor = m_last;
appendRun();
m_direction = U_EUROPEAN_NUMBER;
break;
case U_EUROPEAN_NUMBER_SEPARATOR:
case U_COMMON_NUMBER_SEPARATOR:
if (m_status.eor == U_EUROPEAN_NUMBER)
break;
FALLTHROUGH;
case U_EUROPEAN_NUMBER_TERMINATOR:
case U_BOUNDARY_NEUTRAL:
case U_BLOCK_SEPARATOR:
case U_SEGMENT_SEPARATOR:
case U_WHITE_SPACE_NEUTRAL:
case U_OTHER_NEUTRAL:
if (m_status.eor == U_EUROPEAN_NUMBER) {
if (m_status.lastStrong == U_RIGHT_TO_LEFT) {
// ENs on both sides behave like Rs, so the neutrals should be R.
// Terminate the EN run.
appendRun();
// Make an R run.
m_eor = m_status.last == U_EUROPEAN_NUMBER_TERMINATOR ? m_lastBeforeET : m_last;
m_direction = U_RIGHT_TO_LEFT;
appendRun();
// Begin a new EN run.
m_direction = U_EUROPEAN_NUMBER;
}
} else if (m_status.eor == U_ARABIC_NUMBER) {
// Terminate the AN run.
appendRun();
if (m_status.lastStrong == U_RIGHT_TO_LEFT || context()->dir() == U_RIGHT_TO_LEFT) {
// Make an R run.
m_eor = m_status.last == U_EUROPEAN_NUMBER_TERMINATOR ? m_lastBeforeET : m_last;
m_direction = U_RIGHT_TO_LEFT;
appendRun();
// Begin a new EN run.
m_direction = U_EUROPEAN_NUMBER;
}
} else if (m_status.lastStrong == U_RIGHT_TO_LEFT) {
// Extend the R run to include the neutrals.
m_eor = m_status.last == U_EUROPEAN_NUMBER_TERMINATOR ? m_lastBeforeET : m_last;
m_direction = U_RIGHT_TO_LEFT;
appendRun();
// Begin a new EN run.
m_direction = U_EUROPEAN_NUMBER;
}
break;
default:
break;
}
m_eor = m_current;
m_status.eor = U_EUROPEAN_NUMBER;
if (m_direction == U_OTHER_NEUTRAL)
m_direction = U_LEFT_TO_RIGHT;
break;
}
FALLTHROUGH;
case U_ARABIC_NUMBER:
dirCurrent = U_ARABIC_NUMBER;
switch (m_status.last) {
case U_LEFT_TO_RIGHT:
if (context()->dir() == U_LEFT_TO_RIGHT)
appendRun();
break;
case U_ARABIC_NUMBER:
break;
case U_RIGHT_TO_LEFT:
case U_RIGHT_TO_LEFT_ARABIC:
case U_EUROPEAN_NUMBER:
m_eor = m_last;
appendRun();
break;
case U_COMMON_NUMBER_SEPARATOR:
if (m_status.eor == U_ARABIC_NUMBER)
break;
FALLTHROUGH;
case U_EUROPEAN_NUMBER_SEPARATOR:
case U_EUROPEAN_NUMBER_TERMINATOR:
case U_BOUNDARY_NEUTRAL:
case U_BLOCK_SEPARATOR:
case U_SEGMENT_SEPARATOR:
case U_WHITE_SPACE_NEUTRAL:
case U_OTHER_NEUTRAL:
if (m_status.eor == U_ARABIC_NUMBER
|| (m_status.eor == U_EUROPEAN_NUMBER && (m_status.lastStrong == U_RIGHT_TO_LEFT || context()->dir() == U_RIGHT_TO_LEFT))
|| (m_status.eor != U_EUROPEAN_NUMBER && m_status.lastStrong == U_LEFT_TO_RIGHT && context()->dir() == U_RIGHT_TO_LEFT)) {
// Terminate the run before the neutrals.
appendRun();
// Begin an R run for the neutrals.
m_direction = U_RIGHT_TO_LEFT;
} else if (m_direction == U_OTHER_NEUTRAL)
m_direction = m_status.lastStrong == U_LEFT_TO_RIGHT ? U_LEFT_TO_RIGHT : U_RIGHT_TO_LEFT;
m_eor = m_last;
appendRun();
break;
default:
break;
}
m_eor = m_current;
m_status.eor = U_ARABIC_NUMBER;
if (m_direction == U_OTHER_NEUTRAL)
m_direction = U_ARABIC_NUMBER;
break;
case U_EUROPEAN_NUMBER_SEPARATOR:
case U_COMMON_NUMBER_SEPARATOR:
break;
case U_EUROPEAN_NUMBER_TERMINATOR:
if (m_status.last == U_EUROPEAN_NUMBER) {
dirCurrent = U_EUROPEAN_NUMBER;
m_eor = m_current;
m_status.eor = dirCurrent;
} else if (m_status.last != U_EUROPEAN_NUMBER_TERMINATOR)
m_lastBeforeET = m_emptyRun ? m_eor : m_last;
break;
// boundary neutrals should be ignored
case U_BOUNDARY_NEUTRAL:
if (m_eor == m_last)
m_eor = m_current;
break;
// neutrals
case U_BLOCK_SEPARATOR:
// FIXME: What do we do with newline and paragraph separators that come to here?
break;
case U_SEGMENT_SEPARATOR:
// FIXME: Implement rule L1.
break;
case U_WHITE_SPACE_NEUTRAL:
break;
case U_OTHER_NEUTRAL:
break;
default:
break;
}
if (pastEnd && (m_eor == m_current || !needsContinuePastEnd())) {
if (!m_reachedEndOfLine) {
m_eor = endOfLine;
switch (m_status.eor) {
case U_LEFT_TO_RIGHT:
case U_RIGHT_TO_LEFT:
case U_ARABIC_NUMBER:
m_direction = m_status.eor;
break;
case U_EUROPEAN_NUMBER:
m_direction = m_status.lastStrong == U_LEFT_TO_RIGHT ? U_LEFT_TO_RIGHT : U_EUROPEAN_NUMBER;
break;
default:
ASSERT_NOT_REACHED();
}
appendRun();
}
m_current = end;
m_status = stateAtEnd.m_status;
m_sor = stateAtEnd.m_sor;
m_eor = stateAtEnd.m_eor;
m_last = stateAtEnd.m_last;
m_reachedEndOfLine = stateAtEnd.m_reachedEndOfLine;
m_lastBeforeET = stateAtEnd.m_lastBeforeET;
m_emptyRun = stateAtEnd.m_emptyRun;
m_direction = U_OTHER_NEUTRAL;
break;
}
updateStatusLastFromCurrentDirection(dirCurrent);
m_last = m_current;
if (m_emptyRun) {
m_sor = m_current;
m_emptyRun = false;
}
increment();
if (!m_currentExplicitEmbeddingSequence.isEmpty()) {
bool committed = commitExplicitEmbedding();
if (committed && pastEnd) {
m_current = end;
m_status = stateAtEnd.m_status;
m_sor = stateAtEnd.m_sor;
m_eor = stateAtEnd.m_eor;
m_last = stateAtEnd.m_last;
m_reachedEndOfLine = stateAtEnd.m_reachedEndOfLine;
m_lastBeforeET = stateAtEnd.m_lastBeforeET;
m_emptyRun = stateAtEnd.m_emptyRun;
m_direction = U_OTHER_NEUTRAL;
break;
}
}
if (!pastEnd && (m_current == end || m_current.atEnd())) {
if (m_emptyRun)
break;
stateAtEnd.m_status = m_status;
stateAtEnd.m_sor = m_sor;
stateAtEnd.m_eor = m_eor;
stateAtEnd.m_last = m_last;
stateAtEnd.m_reachedEndOfLine = m_reachedEndOfLine;
stateAtEnd.m_lastBeforeET = m_lastBeforeET;
stateAtEnd.m_emptyRun = m_emptyRun;
endOfLine = m_last;
pastEnd = true;
}
}
m_runs.setLogicallyLastRun(m_runs.lastRun());
reorderRunsFromLevels();
endOfLine = Iterator();
}
template<typename Iterator, typename Run, typename DerivedClass>
void BidiResolverBase<Iterator, Run, DerivedClass>::setWhitespaceCollapsingTransitionForIsolatedRun(Run& run, size_t transition)
{
ASSERT(!m_whitespaceCollapsingTransitionForIsolatedRun.contains(&run));
m_whitespaceCollapsingTransitionForIsolatedRun.add(&run, transition);
}
template<typename Iterator, typename Run, typename DerivedClass>
unsigned BidiResolverBase<Iterator, Run, DerivedClass>::whitespaceCollapsingTransitionForIsolatedRun(Run& run)
{
return m_whitespaceCollapsingTransitionForIsolatedRun.take(&run);
}
} // namespace WebCore