text: // Copyright 2016 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/fpdfdoc/csection.h"
  
  #include <algorithm>
  
  #include "core/fpdfdoc/cline.h"
  #include "core/fpdfdoc/cpdf_variabletext.h"
  #include "core/fpdfdoc/cpvt_wordinfo.h"
  #include "third_party/base/stl_util.h"
  
  CSection::CSection(CPDF_VariableText* pVT) : m_pVT(pVT) {
    ASSERT(m_pVT);
  }
  
  CSection::~CSection() = default;
  
  void CSection::ResetLinePlace() {
    int32_t i = 0;
    for (auto& pLine : m_LineArray) {
      pLine->LinePlace = CPVT_WordPlace(SecPlace.nSecIndex, i, -1);
      ++i;
    }
  }
  
  CPVT_WordPlace CSection::AddWord(const CPVT_WordPlace& place,
                                   const CPVT_WordInfo& wordinfo) {
    int32_t nWordIndex = pdfium::clamp(
        place.nWordIndex, 0, pdfium::CollectionSize<int32_t>(m_WordArray));
    m_WordArray.insert(m_WordArray.begin() + nWordIndex,
                       std::make_unique<CPVT_WordInfo>(wordinfo));
    return place;
  }
  
  CPVT_WordPlace CSection::AddLine(const CPVT_LineInfo& lineinfo) {
    m_LineArray.push_back(std::make_unique<CLine>(lineinfo));
    return CPVT_WordPlace(SecPlace.nSecIndex, m_LineArray.size() - 1, -1);
  }
  
  CPVT_FloatRect CSection::Rearrange() {
    if (m_pVT->GetCharArray() > 0)
      return CTypeset(this).CharArray();
    return CTypeset(this).Typeset();
  }
  
  CFX_SizeF CSection::GetSectionSize(float fFontSize) {
    return CTypeset(this).GetEditSize(fFontSize);
  }
  
  CPVT_WordPlace CSection::GetBeginWordPlace() const {
    if (m_LineArray.empty())
      return SecPlace;
    return m_LineArray.front()->GetBeginWordPlace();
  }
  
  CPVT_WordPlace CSection::GetEndWordPlace() const {
    if (m_LineArray.empty())
      return SecPlace;
    return m_LineArray.back()->GetEndWordPlace();
  }
  
  CPVT_WordPlace CSection::GetPrevWordPlace(const CPVT_WordPlace& place) const {
    if (place.nLineIndex < 0)
      return GetBeginWordPlace();
  
    if (place.nLineIndex >= pdfium::CollectionSize<int32_t>(m_LineArray))
      return GetEndWordPlace();
  
    CLine* pLine = m_LineArray[place.nLineIndex].get();
    if (place.nWordIndex == pLine->m_LineInfo.nBeginWordIndex)
      return CPVT_WordPlace(place.nSecIndex, place.nLineIndex, -1);
  
    if (place.nWordIndex >= pLine->m_LineInfo.nBeginWordIndex)
      return pLine->GetPrevWordPlace(place);
  
    if (!pdfium::IndexInBounds(m_LineArray, place.nLineIndex - 1))
      return place;
  
    return m_LineArray[place.nLineIndex - 1]->GetEndWordPlace();
  }
  
  CPVT_WordPlace CSection::GetNextWordPlace(const CPVT_WordPlace& place) const {
    if (place.nLineIndex < 0)
      return GetBeginWordPlace();
  
    if (place.nLineIndex >= pdfium::CollectionSize<int32_t>(m_LineArray))
      return GetEndWordPlace();
  
    CLine* pLine = m_LineArray[place.nLineIndex].get();
    if (place.nWordIndex < pLine->m_LineInfo.nEndWordIndex)
      return pLine->GetNextWordPlace(place);
  
    if (!pdfium::IndexInBounds(m_LineArray, place.nLineIndex + 1))
      return place;
  
    return m_LineArray[place.nLineIndex + 1]->GetBeginWordPlace();
  }
  
  void CSection::UpdateWordPlace(CPVT_WordPlace& place) const {
    int32_t nLeft = 0;
    int32_t nRight = pdfium::CollectionSize<int32_t>(m_LineArray) - 1;
    int32_t nMid = (nLeft + nRight) / 2;
    while (nLeft <= nRight) {
      CLine* pLine = m_LineArray[nMid].get();
      if (place.nWordIndex < pLine->m_LineInfo.nBeginWordIndex) {
        nRight = nMid - 1;
        nMid = (nLeft + nRight) / 2;
      } else if (place.nWordIndex > pLine->m_LineInfo.nEndWordIndex) {
        nLeft = nMid + 1;
        nMid = (nLeft + nRight) / 2;
      } else {
        place.nLineIndex = nMid;
        return;
      }
    }
  }
  
  CPVT_WordPlace CSection::SearchWordPlace(const CFX_PointF& point) const {
    CPVT_WordPlace place = GetBeginWordPlace();
    bool bUp = true;
    bool bDown = true;
    int32_t nLeft = 0;
    int32_t nRight = pdfium::CollectionSize<int32_t>(m_LineArray) - 1;
    int32_t nMid = pdfium::CollectionSize<int32_t>(m_LineArray) / 2;
    while (nLeft <= nRight) {
      CLine* pLine = m_LineArray[nMid].get();
      float fTop = pLine->m_LineInfo.fLineY - pLine->m_LineInfo.fLineAscent -
                   m_pVT->GetLineLeading();
      float fBottom = pLine->m_LineInfo.fLineY - pLine->m_LineInfo.fLineDescent;
      if (IsFloatBigger(point.y, fTop))
        bUp = false;
      if (IsFloatSmaller(point.y, fBottom))
        bDown = false;
      if (IsFloatSmaller(point.y, fTop)) {
        nRight = nMid - 1;
        nMid = (nLeft + nRight) / 2;
        continue;
      }
      if (IsFloatBigger(point.y, fBottom)) {
        nLeft = nMid + 1;
        nMid = (nLeft + nRight) / 2;
        continue;
      }
      place = SearchWordPlace(
          point.x,
          CPVT_WordRange(pLine->GetNextWordPlace(pLine->GetBeginWordPlace()),
                         pLine->GetEndWordPlace()));
      place.nLineIndex = nMid;
      return place;
    }
    if (bUp)
      place = GetBeginWordPlace();
    if (bDown)
      place = GetEndWordPlace();
    return place;
  }
  
  CPVT_WordPlace CSection::SearchWordPlace(
      float fx,
      const CPVT_WordPlace& lineplace) const {
    if (!pdfium::IndexInBounds(m_LineArray, lineplace.nLineIndex))
      return GetBeginWordPlace();
  
    CLine* pLine = m_LineArray[lineplace.nLineIndex].get();
    return SearchWordPlace(
        fx - m_Rect.left,
        CPVT_WordRange(pLine->GetNextWordPlace(pLine->GetBeginWordPlace()),
                       pLine->GetEndWordPlace()));
  }
  
  CPVT_WordPlace CSection::SearchWordPlace(float fx,
                                           const CPVT_WordRange& range) const {
    CPVT_WordPlace wordplace = range.BeginPos;
    wordplace.nWordIndex = -1;
  
    int32_t nLeft = range.BeginPos.nWordIndex;
    int32_t nRight = range.EndPos.nWordIndex + 1;
    int32_t nMid = (nLeft + nRight) / 2;
    while (nLeft < nRight) {
      if (nMid == nLeft)
        break;
      if (nMid == nRight) {
        nMid--;
        break;
      }
      if (!pdfium::IndexInBounds(m_WordArray, nMid))
        break;
      CPVT_WordInfo* pWord = m_WordArray[nMid].get();
      if (fx > pWord->fWordX + m_pVT->GetWordWidth(*pWord) * VARIABLETEXT_HALF) {
        nLeft = nMid;
        nMid = (nLeft + nRight) / 2;
        continue;
      }
      nRight = nMid;
      nMid = (nLeft + nRight) / 2;
    }
    if (pdfium::IndexInBounds(m_WordArray, nMid)) {
      CPVT_WordInfo* pWord = m_WordArray[nMid].get();
      if (fx > pWord->fWordX + m_pVT->GetWordWidth(*pWord) * VARIABLETEXT_HALF)
        wordplace.nWordIndex = nMid;
    }
    return wordplace;
  }
  
  void CSection::ClearLeftWords(int32_t nWordIndex) {
    for (int32_t i = nWordIndex; i >= 0; i--) {
      if (pdfium::IndexInBounds(m_WordArray, i))
        m_WordArray.erase(m_WordArray.begin() + i);
    }
  }
  
  void CSection::ClearRightWords(int32_t nWordIndex) {
    int32_t sz = pdfium::CollectionSize<int32_t>(m_WordArray);
    for (int32_t i = sz - 1; i > nWordIndex; i--) {
      if (pdfium::IndexInBounds(m_WordArray, i))
        m_WordArray.erase(m_WordArray.begin() + i);
    }
  }
  
  void CSection::ClearMidWords(int32_t nBeginIndex, int32_t nEndIndex) {
    for (int32_t i = nEndIndex; i > nBeginIndex; i--) {
      if (pdfium::IndexInBounds(m_WordArray, i))
        m_WordArray.erase(m_WordArray.begin() + i);
    }
  }
  
  void CSection::ClearWords(const CPVT_WordRange& PlaceRange) {
    CPVT_WordPlace SecBeginPos = GetBeginWordPlace();
    CPVT_WordPlace SecEndPos = GetEndWordPlace();
    if (PlaceRange.BeginPos >= SecBeginPos) {
      if (PlaceRange.EndPos <= SecEndPos) {
        ClearMidWords(PlaceRange.BeginPos.nWordIndex,
                      PlaceRange.EndPos.nWordIndex);
      } else {
        ClearRightWords(PlaceRange.BeginPos.nWordIndex);
      }
    } else if (PlaceRange.EndPos <= SecEndPos) {
      ClearLeftWords(PlaceRange.EndPos.nWordIndex);
    } else {
      m_WordArray.clear();
    }
  }
  
  void CSection::ClearWord(const CPVT_WordPlace& place) {
    if (pdfium::IndexInBounds(m_WordArray, place.nWordIndex))
      m_WordArray.erase(m_WordArray.begin() + place.nWordIndex);
  }
  