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// Copyright 2014 PDFium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
// Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
#include "core/fxcrt/fx_bidi.h"
#include <algorithm>
#include "core/fxcrt/fx_ucd.h"
#include "third_party/base/ptr_util.h"
CFX_BidiChar::CFX_BidiChar()
: m_CurrentSegment({0, 0, NEUTRAL}), m_LastSegment({0, 0, NEUTRAL}) {}
bool CFX_BidiChar::AppendChar(wchar_t wch) {
uint32_t dwProps = FX_GetUnicodeProperties(wch);
int32_t iBidiCls = (dwProps & FX_BIDICLASSBITSMASK) >> FX_BIDICLASSBITS;
Direction direction = NEUTRAL;
switch (iBidiCls) {
case FX_BIDICLASS_L:
case FX_BIDICLASS_AN:
case FX_BIDICLASS_EN:
direction = LEFT;
break;
case FX_BIDICLASS_R:
case FX_BIDICLASS_AL:
direction = RIGHT;
break;
}
bool bChangeDirection = (direction != m_CurrentSegment.direction);
if (bChangeDirection)
StartNewSegment(direction);
m_CurrentSegment.count++;
return bChangeDirection;
}
bool CFX_BidiChar::EndChar() {
StartNewSegment(NEUTRAL);
return m_LastSegment.count > 0;
}
void CFX_BidiChar::StartNewSegment(CFX_BidiChar::Direction direction) {
m_LastSegment = m_CurrentSegment;
m_CurrentSegment.start += m_CurrentSegment.count;
m_CurrentSegment.count = 0;
m_CurrentSegment.direction = direction;
}
CFX_BidiString::CFX_BidiString(const CFX_WideString& str)
: m_Str(str),
m_pBidiChar(pdfium::MakeUnique<CFX_BidiChar>()),
m_eOverallDirection(CFX_BidiChar::LEFT) {
for (const auto& c : m_Str) {
if (m_pBidiChar->AppendChar(c))
m_Order.push_back(m_pBidiChar->GetSegmentInfo());
}
if (m_pBidiChar->EndChar())
m_Order.push_back(m_pBidiChar->GetSegmentInfo());
size_t nR2L = std::count_if(m_Order.begin(), m_Order.end(),
[](const CFX_BidiChar::Segment& seg) {
return seg.direction == CFX_BidiChar::RIGHT;
});
size_t nL2R = std::count_if(m_Order.begin(), m_Order.end(),
[](const CFX_BidiChar::Segment& seg) {
return seg.direction == CFX_BidiChar::LEFT;
});
if (nR2L > 0 && nR2L >= nL2R)
SetOverallDirectionRight();
}
CFX_BidiString::~CFX_BidiString() {}
void CFX_BidiString::SetOverallDirectionRight() {
if (m_eOverallDirection != CFX_BidiChar::RIGHT) {
std::reverse(m_Order.begin(), m_Order.end());
m_eOverallDirection = CFX_BidiChar::RIGHT;
}
}