// 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/fpdftext/cpdf_textpage.h"

#include <algorithm>
#include <utility>
#include <vector>

#include "core/fpdfapi/font/cpdf_font.h"
#include "core/fpdfapi/page/cpdf_form.h"
#include "core/fpdfapi/page/cpdf_formobject.h"
#include "core/fpdfapi/page/cpdf_page.h"
#include "core/fpdfapi/page/cpdf_pageobject.h"
#include "core/fpdfapi/page/cpdf_textobject.h"
#include "core/fpdfapi/parser/cpdf_dictionary.h"
#include "core/fpdfapi/parser/cpdf_string.h"
#include "core/fpdftext/unicodenormalizationdata.h"
#include "core/fxcrt/fx_bidi.h"
#include "core/fxcrt/fx_ext.h"
#include "core/fxcrt/fx_ucd.h"
#include "third_party/base/stl_util.h"

namespace {

const FX_FLOAT kDefaultFontSize = 1.0f;
const uint16_t* const g_UnicodeData_Normalization_Maps[5] = {
    nullptr, g_UnicodeData_Normalization_Map1, g_UnicodeData_Normalization_Map2,
    g_UnicodeData_Normalization_Map3, g_UnicodeData_Normalization_Map4};

FX_FLOAT NormalizeThreshold(FX_FLOAT threshold) {
  if (threshold < 300)
    return threshold / 2.0f;
  if (threshold < 500)
    return threshold / 4.0f;
  if (threshold < 700)
    return threshold / 5.0f;
  return threshold / 6.0f;
}

FX_FLOAT CalculateBaseSpace(const CPDF_TextObject* pTextObj,
                            const CFX_Matrix& matrix) {
  FX_FLOAT baseSpace = 0.0;
  const int nItems = pTextObj->CountItems();
  if (pTextObj->m_TextState.GetCharSpace() && nItems >= 3) {
    bool bAllChar = true;
    FX_FLOAT spacing =
        matrix.TransformDistance(pTextObj->m_TextState.GetCharSpace());
    baseSpace = spacing;
    for (int i = 0; i < nItems; i++) {
      CPDF_TextObjectItem item;
      pTextObj->GetItemInfo(i, &item);
      if (item.m_CharCode == static_cast<uint32_t>(-1)) {
        FX_FLOAT fontsize_h = pTextObj->m_TextState.GetFontSizeH();
        FX_FLOAT kerning = -fontsize_h * item.m_Origin.x / 1000;
        baseSpace = std::min(baseSpace, kerning + spacing);
        bAllChar = false;
      }
    }
    if (baseSpace < 0.0 || (nItems == 3 && !bAllChar))
      baseSpace = 0.0;
  }
  return baseSpace;
}

FX_STRSIZE Unicode_GetNormalization(FX_WCHAR wch, FX_WCHAR* pDst) {
  wch = wch & 0xFFFF;
  FX_WCHAR wFind = g_UnicodeData_Normalization[wch];
  if (!wFind) {
    if (pDst)
      *pDst = wch;
    return 1;
  }
  if (wFind >= 0x8000) {
    wch = wFind - 0x8000;
    wFind = 1;
  } else {
    wch = wFind & 0x0FFF;
    wFind >>= 12;
  }
  const uint16_t* pMap = g_UnicodeData_Normalization_Maps[wFind];
  if (pMap == g_UnicodeData_Normalization_Map4) {
    pMap = g_UnicodeData_Normalization_Map4 + wch;
    wFind = (FX_WCHAR)(*pMap++);
  } else {
    pMap += wch;
  }
  if (pDst) {
    FX_WCHAR n = wFind;
    while (n--)
      *pDst++ = *pMap++;
  }
  return (FX_STRSIZE)wFind;
}

float MaskPercentFilled(const std::vector<bool>& mask,
                        int32_t start,
                        int32_t end) {
  if (start >= end)
    return 0;
  float count = std::count_if(mask.begin() + start, mask.begin() + end,
                              [](bool r) { return r; });
  return count / (end - start);
}

}  // namespace

FPDF_CHAR_INFO::FPDF_CHAR_INFO()
    : m_Unicode(0),
      m_Charcode(0),
      m_Flag(0),
      m_FontSize(0),
      m_pTextObj(nullptr) {}

FPDF_CHAR_INFO::~FPDF_CHAR_INFO() {}

PAGECHAR_INFO::PAGECHAR_INFO()
    : m_Index(0), m_CharCode(0), m_Unicode(0), m_Flag(0), m_pTextObj(nullptr) {}

PAGECHAR_INFO::PAGECHAR_INFO(const PAGECHAR_INFO&) = default;

PAGECHAR_INFO::~PAGECHAR_INFO() {}

CPDF_TextPage::CPDF_TextPage(const CPDF_Page* pPage, FPDFText_Direction flags)
    : m_pPage(pPage),
      m_parserflag(flags),
      m_pPreTextObj(nullptr),
      m_bIsParsed(false),
      m_TextlineDir(TextOrientation::Unknown) {
  m_TextBuf.EstimateSize(0, 10240);
  m_DisplayMatrix =
      pPage->GetDisplayMatrix(0, 0, static_cast<int>(pPage->GetPageWidth()),
                              static_cast<int>(pPage->GetPageHeight()), 0);
}

CPDF_TextPage::~CPDF_TextPage() {}

bool CPDF_TextPage::IsControlChar(const PAGECHAR_INFO& charInfo) {
  switch (charInfo.m_Unicode) {
    case 0x2:
    case 0x3:
    case 0x93:
    case 0x94:
    case 0x96:
    case 0x97:
    case 0x98:
    case 0xfffe:
      return charInfo.m_Flag != FPDFTEXT_CHAR_HYPHEN;
    default:
      return false;
  }
}

void CPDF_TextPage::ParseTextPage() {
  m_bIsParsed = false;
  m_TextBuf.Clear();
  m_CharList.clear();
  m_pPreTextObj = nullptr;
  ProcessObject();

  m_bIsParsed = true;
  m_CharIndex.clear();
  int nCount = pdfium::CollectionSize<int>(m_CharList);
  if (nCount)
    m_CharIndex.push_back(0);

  for (int i = 0; i < nCount; i++) {
    int indexSize = pdfium::CollectionSize<int>(m_CharIndex);
    const PAGECHAR_INFO& charinfo = m_CharList[i];
    if (charinfo.m_Flag == FPDFTEXT_CHAR_GENERATED ||
        (charinfo.m_Unicode != 0 && !IsControlChar(charinfo))) {
      if (indexSize % 2) {
        m_CharIndex.push_back(1);
      } else {
        if (indexSize <= 0)
          continue;
        m_CharIndex[indexSize - 1] += 1;
      }
    } else {
      if (indexSize % 2) {
        if (indexSize <= 0)
          continue;
        m_CharIndex[indexSize - 1] = i + 1;
      } else {
        m_CharIndex.push_back(i + 1);
      }
    }
  }
  int indexSize = pdfium::CollectionSize<int>(m_CharIndex);
  if (indexSize % 2)
    m_CharIndex.erase(m_CharIndex.begin() + indexSize - 1);
}

int CPDF_TextPage::CountChars() const {
  return pdfium::CollectionSize<int>(m_CharList);
}

int CPDF_TextPage::CharIndexFromTextIndex(int TextIndex) const {
  int indexSize = pdfium::CollectionSize<int>(m_CharIndex);
  int count = 0;
  for (int i = 0; i < indexSize; i += 2) {
    count += m_CharIndex[i + 1];
    if (count > TextIndex)
      return TextIndex - count + m_CharIndex[i + 1] + m_CharIndex[i];
  }
  return -1;
}

int CPDF_TextPage::TextIndexFromCharIndex(int CharIndex) const {
  int indexSize = pdfium::CollectionSize<int>(m_CharIndex);
  int count = 0;
  for (int i = 0; i < indexSize; i += 2) {
    count += m_CharIndex[i + 1];
    if (m_CharIndex[i + 1] + m_CharIndex[i] > CharIndex) {
      if (CharIndex - m_CharIndex[i] < 0)
        return -1;

      return CharIndex - m_CharIndex[i] + count - m_CharIndex[i + 1];
    }
  }
  return -1;
}

std::vector<CFX_FloatRect> CPDF_TextPage::GetRectArray(int start,
                                                       int nCount) const {
  if (start < 0 || nCount == 0 || !m_bIsParsed)
    return std::vector<CFX_FloatRect>();

  if (nCount + start > pdfium::CollectionSize<int>(m_CharList) ||
      nCount == -1) {
    nCount = pdfium::CollectionSize<int>(m_CharList) - start;
  }

  std::vector<CFX_FloatRect> rectArray;
  CPDF_TextObject* pCurObj = nullptr;
  CFX_FloatRect rect;
  int curPos = start;
  bool bFlagNewRect = true;
  while (nCount--) {
    PAGECHAR_INFO info_curchar = m_CharList[curPos++];
    if (info_curchar.m_Flag == FPDFTEXT_CHAR_GENERATED)
      continue;
    if (info_curchar.m_CharBox.Width() < 0.01 ||
        info_curchar.m_CharBox.Height() < 0.01) {
      continue;
    }
    if (!pCurObj)
      pCurObj = info_curchar.m_pTextObj;
    if (pCurObj != info_curchar.m_pTextObj) {
      rectArray.push_back(rect);
      pCurObj = info_curchar.m_pTextObj;
      bFlagNewRect = true;
    }
    if (bFlagNewRect) {
      CFX_Matrix matrix = info_curchar.m_pTextObj->GetTextMatrix();
      matrix.Concat(info_curchar.m_Matrix);

      CFX_Matrix matrix_reverse;
      matrix_reverse.SetReverse(matrix);

      CFX_PointF origin = matrix_reverse.Transform(info_curchar.m_Origin);
      rect.left = info_curchar.m_CharBox.left;
      rect.right = info_curchar.m_CharBox.right;
      if (pCurObj->GetFont()->GetTypeDescent()) {
        rect.bottom = origin.y +
                      pCurObj->GetFont()->GetTypeDescent() *
                          pCurObj->GetFontSize() / 1000;
        FX_FLOAT xPosTemp = origin.x;
        matrix.TransformPoint(xPosTemp, rect.bottom);
      } else {
        rect.bottom = info_curchar.m_CharBox.bottom;
      }
      if (pCurObj->GetFont()->GetTypeAscent()) {
        rect.top =
            origin.y +
            pCurObj->GetFont()->GetTypeAscent() * pCurObj->GetFontSize() / 1000;
        FX_FLOAT xPosTemp =
            origin.x +
            GetCharWidth(info_curchar.m_CharCode, pCurObj->GetFont()) *
                pCurObj->GetFontSize() / 1000;
        matrix.TransformPoint(xPosTemp, rect.top);
      } else {
        rect.top = info_curchar.m_CharBox.top;
      }
      bFlagNewRect = false;
      rect = info_curchar.m_CharBox;
      rect.Normalize();
    } else {
      info_curchar.m_CharBox.Normalize();
      rect.left = std::min(rect.left, info_curchar.m_CharBox.left);
      rect.right = std::max(rect.right, info_curchar.m_CharBox.right);
      rect.top = std::max(rect.top, info_curchar.m_CharBox.top);
      rect.bottom = std::min(rect.bottom, info_curchar.m_CharBox.bottom);
    }
  }
  rectArray.push_back(rect);
  return rectArray;
}

int CPDF_TextPage::GetIndexAtPos(const CFX_PointF& point,
                                 FX_FLOAT xTolerance,
                                 FX_FLOAT yTolerance) const {
  if (!m_bIsParsed)
    return -3;

  int pos = 0;
  int NearPos = -1;
  double xdif = 5000;
  double ydif = 5000;
  while (pos < pdfium::CollectionSize<int>(m_CharList)) {
    PAGECHAR_INFO charinfo = m_CharList[pos];
    CFX_FloatRect charrect = charinfo.m_CharBox;
    if (charrect.Contains(point))
      break;
    if (xTolerance > 0 || yTolerance > 0) {
      CFX_FloatRect charRectExt;
      charrect.Normalize();
      charRectExt.left = charrect.left - xTolerance / 2;
      charRectExt.right = charrect.right + xTolerance / 2;
      charRectExt.top = charrect.top + yTolerance / 2;
      charRectExt.bottom = charrect.bottom - yTolerance / 2;
      if (charRectExt.Contains(point)) {
        double curXdif, curYdif;
        curXdif = FXSYS_fabs(point.x - charrect.left) <
                          FXSYS_fabs(point.x - charrect.right)
                      ? FXSYS_fabs(point.x - charrect.left)
                      : FXSYS_fabs(point.x - charrect.right);
        curYdif = FXSYS_fabs(point.y - charrect.bottom) <
                          FXSYS_fabs(point.y - charrect.top)
                      ? FXSYS_fabs(point.y - charrect.bottom)
                      : FXSYS_fabs(point.y - charrect.top);
        if (curYdif + curXdif < xdif + ydif) {
          ydif = curYdif;
          xdif = curXdif;
          NearPos = pos;
        }
      }
    }
    ++pos;
  }
  return pos < pdfium::CollectionSize<int>(m_CharList) ? pos : NearPos;
}

CFX_WideString CPDF_TextPage::GetTextByRect(const CFX_FloatRect& rect) const {
  if (!m_bIsParsed)
    return CFX_WideString();

  FX_FLOAT posy = 0;
  bool IsContainPreChar = false;
  bool IsAddLineFeed = false;
  CFX_WideString strText;
  for (const auto& charinfo : m_CharList) {
    if (IsRectIntersect(rect, charinfo.m_CharBox)) {
      if (FXSYS_fabs(posy - charinfo.m_Origin.y) > 0 && !IsContainPreChar &&
          IsAddLineFeed) {
        posy = charinfo.m_Origin.y;
        if (!strText.IsEmpty())
          strText += L"\r\n";
      }
      IsContainPreChar = true;
      IsAddLineFeed = false;
      if (charinfo.m_Unicode)
        strText += charinfo.m_Unicode;
    } else if (charinfo.m_Unicode == 32) {
      if (IsContainPreChar && charinfo.m_Unicode) {
        strText += charinfo.m_Unicode;
        IsContainPreChar = false;
        IsAddLineFeed = false;
      }
    } else {
      IsContainPreChar = false;
      IsAddLineFeed = true;
    }
  }
  return strText;
}

int CPDF_TextPage::GetIndexAtPos(FX_FLOAT x,
                                 FX_FLOAT y,
                                 FX_FLOAT xTolerance,
                                 FX_FLOAT yTolerance) const {
  CFX_PointF point(x, y);
  return GetIndexAtPos(point, xTolerance, yTolerance);
}

void CPDF_TextPage::GetCharInfo(int index, FPDF_CHAR_INFO* info) const {
  if (!m_bIsParsed)
    return;

  if (index < 0 || index >= pdfium::CollectionSize<int>(m_CharList))
    return;

  const PAGECHAR_INFO& charinfo = m_CharList[index];
  info->m_Charcode = charinfo.m_CharCode;
  info->m_Origin = charinfo.m_Origin;
  info->m_Unicode = charinfo.m_Unicode;
  info->m_Flag = charinfo.m_Flag;
  info->m_CharBox = charinfo.m_CharBox;
  info->m_pTextObj = charinfo.m_pTextObj;
  if (charinfo.m_pTextObj && charinfo.m_pTextObj->GetFont())
    info->m_FontSize = charinfo.m_pTextObj->GetFontSize();
  else
    info->m_FontSize = kDefaultFontSize;
  info->m_Matrix = charinfo.m_Matrix;
}

void CPDF_TextPage::CheckMarkedContentObject(int32_t& start,
                                             int32_t& nCount) const {
  PAGECHAR_INFO charinfo = m_CharList[start];
  PAGECHAR_INFO charinfo2 = m_CharList[start + nCount - 1];
  if (FPDFTEXT_CHAR_PIECE != charinfo.m_Flag &&
      FPDFTEXT_CHAR_PIECE != charinfo2.m_Flag) {
    return;
  }
  if (FPDFTEXT_CHAR_PIECE == charinfo.m_Flag) {
    PAGECHAR_INFO charinfo1 = charinfo;
    int startIndex = start;
    while (FPDFTEXT_CHAR_PIECE == charinfo1.m_Flag &&
           charinfo1.m_Index == charinfo.m_Index) {
      startIndex--;
      if (startIndex < 0)
        break;
      charinfo1 = m_CharList[startIndex];
    }
    startIndex++;
    start = startIndex;
  }
  if (FPDFTEXT_CHAR_PIECE == charinfo2.m_Flag) {
    PAGECHAR_INFO charinfo3 = charinfo2;
    int endIndex = start + nCount - 1;
    while (FPDFTEXT_CHAR_PIECE == charinfo3.m_Flag &&
           charinfo3.m_Index == charinfo2.m_Index) {
      endIndex++;
      if (endIndex >= pdfium::CollectionSize<int>(m_CharList))
        break;
      charinfo3 = m_CharList[endIndex];
    }
    endIndex--;
    nCount = endIndex - start + 1;
  }
}

CFX_WideString CPDF_TextPage::GetPageText(int start, int nCount) const {
  if (!m_bIsParsed || nCount == 0)
    return L"";

  if (start < 0)
    start = 0;

  if (nCount == -1) {
    nCount = pdfium::CollectionSize<int>(m_CharList) - start;
    return CFX_WideString(
        m_TextBuf.AsStringC().Mid(start, m_TextBuf.AsStringC().GetLength()));
  }
  if (nCount <= 0 || m_CharList.empty())
    return L"";
  if (nCount + start > pdfium::CollectionSize<int>(m_CharList) - 1)
    nCount = pdfium::CollectionSize<int>(m_CharList) - start;
  if (nCount <= 0)
    return L"";
  CheckMarkedContentObject(start, nCount);
  int startindex = 0;
  PAGECHAR_INFO charinfo = m_CharList[start];
  int startOffset = 0;
  while (charinfo.m_Index == -1) {
    startOffset++;
    if (startOffset > nCount ||
        start + startOffset >= pdfium::CollectionSize<int>(m_CharList)) {
      return L"";
    }
    charinfo = m_CharList[start + startOffset];
  }
  startindex = charinfo.m_Index;
  charinfo = m_CharList[start + nCount - 1];
  int nCountOffset = 0;
  while (charinfo.m_Index == -1) {
    nCountOffset++;
    if (nCountOffset >= nCount)
      return L"";
    charinfo = m_CharList[start + nCount - nCountOffset - 1];
  }
  nCount = start + nCount - nCountOffset - startindex;
  if (nCount <= 0)
    return L"";
  return CFX_WideString(m_TextBuf.AsStringC().Mid(startindex, nCount));
}

int CPDF_TextPage::CountRects(int start, int nCount) {
  if (!m_bIsParsed || start < 0)
    return -1;

  if (nCount == -1 ||
      nCount + start > pdfium::CollectionSize<int>(m_CharList)) {
    nCount = pdfium::CollectionSize<int>(m_CharList) - start;
  }
  m_SelRects = GetRectArray(start, nCount);
  return pdfium::CollectionSize<int>(m_SelRects);
}

void CPDF_TextPage::GetRect(int rectIndex,
                            FX_FLOAT& left,
                            FX_FLOAT& top,
                            FX_FLOAT& right,
                            FX_FLOAT& bottom) const {
  if (!m_bIsParsed)
    return;

  if (rectIndex < 0 || rectIndex >= pdfium::CollectionSize<int>(m_SelRects))
    return;

  left = m_SelRects[rectIndex].left;
  top = m_SelRects[rectIndex].top;
  right = m_SelRects[rectIndex].right;
  bottom = m_SelRects[rectIndex].bottom;
}

CPDF_TextPage::TextOrientation CPDF_TextPage::FindTextlineFlowOrientation()
    const {
  if (m_pPage->GetPageObjectList()->empty())
    return TextOrientation::Unknown;

  const int32_t nPageWidth = static_cast<int32_t>(m_pPage->GetPageWidth());
  const int32_t nPageHeight = static_cast<int32_t>(m_pPage->GetPageHeight());
  if (nPageWidth <= 0 || nPageHeight <= 0)
    return TextOrientation::Unknown;

  std::vector<bool> nHorizontalMask(nPageWidth);
  std::vector<bool> nVerticalMask(nPageHeight);
  FX_FLOAT fLineHeight = 0.0f;
  int32_t nStartH = nPageWidth;
  int32_t nEndH = 0;
  int32_t nStartV = nPageHeight;
  int32_t nEndV = 0;
  for (const auto& pPageObj : *m_pPage->GetPageObjectList()) {
    if (!pPageObj->IsText())
      continue;

    int32_t minH = std::max(static_cast<int32_t>(pPageObj->m_Left), 0);
    int32_t maxH =
        std::min(static_cast<int32_t>(pPageObj->m_Right), nPageWidth);
    int32_t minV = std::max(static_cast<int32_t>(pPageObj->m_Bottom), 0);
    int32_t maxV = std::min(static_cast<int32_t>(pPageObj->m_Top), nPageHeight);
    if (minH >= maxH || minV >= maxV)
      continue;

    for (int32_t i = minH; i < maxH; ++i)
      nHorizontalMask[i] = true;
    for (int32_t i = minV; i < maxV; ++i)
      nVerticalMask[i] = true;

    nStartH = std::min(nStartH, minH);
    nEndH = std::max(nEndH, maxH);
    nStartV = std::min(nStartV, minV);
    nEndV = std::max(nEndV, maxV);

    if (fLineHeight <= 0.0f)
      fLineHeight = pPageObj->m_Top - pPageObj->m_Bottom;
  }
  const int32_t nDoubleLineHeight = 2 * fLineHeight;
  if ((nEndV - nStartV) < nDoubleLineHeight)
    return TextOrientation::Horizontal;
  if ((nEndH - nStartH) < nDoubleLineHeight)
    return TextOrientation::Vertical;

  const FX_FLOAT nSumH = MaskPercentFilled(nHorizontalMask, nStartH, nEndH);
  if (nSumH > 0.8f)
    return TextOrientation::Horizontal;

  const FX_FLOAT nSumV = MaskPercentFilled(nVerticalMask, nStartV, nEndV);
  if (nSumH > nSumV)
    return TextOrientation::Horizontal;
  if (nSumH < nSumV)
    return TextOrientation::Vertical;
  return TextOrientation::Unknown;
}

void CPDF_TextPage::AppendGeneratedCharacter(FX_WCHAR unicode,
                                             const CFX_Matrix& formMatrix) {
  PAGECHAR_INFO generateChar;
  if (!GenerateCharInfo(unicode, generateChar))
    return;

  m_TextBuf.AppendChar(unicode);
  if (!formMatrix.IsIdentity())
    generateChar.m_Matrix = formMatrix;
  m_CharList.push_back(generateChar);
}

void CPDF_TextPage::ProcessObject() {
  if (m_pPage->GetPageObjectList()->empty())
    return;

  m_TextlineDir = FindTextlineFlowOrientation();
  const CPDF_PageObjectList* pObjList = m_pPage->GetPageObjectList();
  for (auto it = pObjList->begin(); it != pObjList->end(); ++it) {
    if (CPDF_PageObject* pObj = it->get()) {
      if (pObj->IsText()) {
        CFX_Matrix matrix;
        ProcessTextObject(pObj->AsText(), matrix, pObjList, it);
      } else if (pObj->IsForm()) {
        CFX_Matrix formMatrix(1, 0, 0, 1, 0, 0);
        ProcessFormObject(pObj->AsForm(), formMatrix);
      }
    }
  }
  for (const auto& obj : m_LineObj)
    ProcessTextObject(obj);

  m_LineObj.clear();
  CloseTempLine();
}

void CPDF_TextPage::ProcessFormObject(CPDF_FormObject* pFormObj,
                                      const CFX_Matrix& formMatrix) {
  CPDF_PageObjectList* pObjectList = pFormObj->m_pForm->GetPageObjectList();
  if (pObjectList->empty())
    return;

  CFX_Matrix curFormMatrix;
  curFormMatrix = pFormObj->m_FormMatrix;
  curFormMatrix.Concat(formMatrix);

  for (auto it = pObjectList->begin(); it != pObjectList->end(); ++it) {
    if (CPDF_PageObject* pPageObj = it->get()) {
      if (pPageObj->IsText())
        ProcessTextObject(pPageObj->AsText(), curFormMatrix, pObjectList, it);
      else if (pPageObj->IsForm())
        ProcessFormObject(pPageObj->AsForm(), curFormMatrix);
    }
  }
}

int CPDF_TextPage::GetCharWidth(uint32_t charCode, CPDF_Font* pFont) const {
  if (charCode == CPDF_Font::kInvalidCharCode)
    return 0;

  if (int w = pFont->GetCharWidthF(charCode))
    return w;

  CFX_ByteString str;
  pFont->AppendChar(str, charCode);
  if (int w = pFont->GetStringWidth(str.c_str(), 1))
    return w;

  return pFont->GetCharBBox(charCode).Width();
}

void CPDF_TextPage::AddCharInfoByLRDirection(FX_WCHAR wChar,
                                             PAGECHAR_INFO info) {
  if (IsControlChar(info)) {
    info.m_Index = -1;
    m_CharList.push_back(info);
    return;
  }

  info.m_Index = m_TextBuf.GetLength();
  if (wChar >= 0xFB00 && wChar <= 0xFB06) {
    FX_WCHAR* pDst = nullptr;
    FX_STRSIZE nCount = Unicode_GetNormalization(wChar, pDst);
    if (nCount >= 1) {
      pDst = FX_Alloc(FX_WCHAR, nCount);
      Unicode_GetNormalization(wChar, pDst);
      for (int nIndex = 0; nIndex < nCount; nIndex++) {
        PAGECHAR_INFO info2 = info;
        info2.m_Unicode = pDst[nIndex];
        info2.m_Flag = FPDFTEXT_CHAR_PIECE;
        m_TextBuf.AppendChar(info2.m_Unicode);
        m_CharList.push_back(info2);
      }
      FX_Free(pDst);
      return;
    }
  }
  m_TextBuf.AppendChar(wChar);
  m_CharList.push_back(info);
}

void CPDF_TextPage::AddCharInfoByRLDirection(FX_WCHAR wChar,
                                             PAGECHAR_INFO info) {
  if (IsControlChar(info)) {
    info.m_Index = -1;
    m_CharList.push_back(info);
    return;
  }

  info.m_Index = m_TextBuf.GetLength();
  wChar = FX_GetMirrorChar(wChar, true, false);
  FX_WCHAR* pDst = nullptr;
  FX_STRSIZE nCount = Unicode_GetNormalization(wChar, pDst);
  if (nCount >= 1) {
    pDst = FX_Alloc(FX_WCHAR, nCount);
    Unicode_GetNormalization(wChar, pDst);
    for (int nIndex = 0; nIndex < nCount; nIndex++) {
      PAGECHAR_INFO info2 = info;
      info2.m_Unicode = pDst[nIndex];
      info2.m_Flag = FPDFTEXT_CHAR_PIECE;
      m_TextBuf.AppendChar(info2.m_Unicode);
      m_CharList.push_back(info2);
    }
    FX_Free(pDst);
    return;
  }
  info.m_Unicode = wChar;
  m_TextBuf.AppendChar(info.m_Unicode);
  m_CharList.push_back(info);
}

void CPDF_TextPage::CloseTempLine() {
  if (m_TempCharList.empty())
    return;

  CFX_WideString str = m_TempTextBuf.MakeString();
  bool bPrevSpace = false;
  for (int i = 0; i < str.GetLength(); i++) {
    if (str.GetAt(i) != ' ') {
      bPrevSpace = false;
      continue;
    }
    if (bPrevSpace) {
      m_TempTextBuf.Delete(i, 1);
      m_TempCharList.erase(m_TempCharList.begin() + i);
      str.Delete(i);
      i--;
    }
    bPrevSpace = true;
  }
  CFX_BidiString bidi(str);
  if (m_parserflag == FPDFText_Direction::Right)
    bidi.SetOverallDirectionRight();
  CFX_BidiChar::Direction eCurrentDirection = bidi.OverallDirection();
  for (const auto& segment : bidi) {
    if (segment.direction == CFX_BidiChar::RIGHT ||
        (segment.direction == CFX_BidiChar::NEUTRAL &&
         eCurrentDirection == CFX_BidiChar::RIGHT)) {
      eCurrentDirection = CFX_BidiChar::RIGHT;
      for (int m = segment.start + segment.count; m > segment.start; --m)
        AddCharInfoByRLDirection(bidi.CharAt(m - 1), m_TempCharList[m - 1]);
    } else {
      eCurrentDirection = CFX_BidiChar::LEFT;
      for (int m = segment.start; m < segment.start + segment.count; m++)
        AddCharInfoByLRDirection(bidi.CharAt(m), m_TempCharList[m]);
    }
  }
  m_TempCharList.clear();
  m_TempTextBuf.Delete(0, m_TempTextBuf.GetLength());
}

void CPDF_TextPage::ProcessTextObject(
    CPDF_TextObject* pTextObj,
    const CFX_Matrix& formMatrix,
    const CPDF_PageObjectList* pObjList,
    CPDF_PageObjectList::const_iterator ObjPos) {
  if (FXSYS_fabs(pTextObj->m_Right - pTextObj->m_Left) < 0.01f)
    return;

  size_t count = m_LineObj.size();
  PDFTEXT_Obj Obj;
  Obj.m_pTextObj = pTextObj;
  Obj.m_formMatrix = formMatrix;
  if (count == 0) {
    m_LineObj.push_back(Obj);
    return;
  }
  if (IsSameAsPreTextObject(pTextObj, pObjList, ObjPos))
    return;

  PDFTEXT_Obj prev_Obj = m_LineObj[count - 1];
  CPDF_TextObjectItem item;
  int nItem = prev_Obj.m_pTextObj->CountItems();
  prev_Obj.m_pTextObj->GetItemInfo(nItem - 1, &item);
  FX_FLOAT prev_width =
      GetCharWidth(item.m_CharCode, prev_Obj.m_pTextObj->GetFont()) *
      prev_Obj.m_pTextObj->GetFontSize() / 1000;

  CFX_Matrix prev_matrix = prev_Obj.m_pTextObj->GetTextMatrix();
  prev_width = FXSYS_fabs(prev_width);
  prev_matrix.Concat(prev_Obj.m_formMatrix);
  prev_width = prev_matrix.TransformDistance(prev_width);
  pTextObj->GetItemInfo(0, &item);
  FX_FLOAT this_width = GetCharWidth(item.m_CharCode, pTextObj->GetFont()) *
                        pTextObj->GetFontSize() / 1000;
  this_width = FXSYS_fabs(this_width);

  CFX_Matrix this_matrix = pTextObj->GetTextMatrix();
  this_width = FXSYS_fabs(this_width);
  this_matrix.Concat(formMatrix);
  this_width = this_matrix.TransformDistance(this_width);

  FX_FLOAT threshold =
      prev_width > this_width ? prev_width / 4 : this_width / 4;
  CFX_PointF prev_pos = m_DisplayMatrix.Transform(
      prev_Obj.m_formMatrix.Transform(prev_Obj.m_pTextObj->GetPos()));
  CFX_PointF this_pos =
      m_DisplayMatrix.Transform(formMatrix.Transform(pTextObj->GetPos()));
  if (FXSYS_fabs(this_pos.y - prev_pos.y) > threshold * 2) {
    for (size_t i = 0; i < count; i++)
      ProcessTextObject(m_LineObj[i]);
    m_LineObj.clear();
    m_LineObj.push_back(Obj);
    return;
  }

  for (size_t i = count; i > 0; --i) {
    PDFTEXT_Obj prev_text_obj = m_LineObj[i - 1];
    CFX_PointF new_prev_pos =
        m_DisplayMatrix.Transform(prev_text_obj.m_formMatrix.Transform(
            prev_text_obj.m_pTextObj->GetPos()));
    if (this_pos.x >= new_prev_pos.x) {
      m_LineObj.insert(m_LineObj.begin() + i, Obj);
      return;
    }
  }
  m_LineObj.insert(m_LineObj.begin(), Obj);
}

FPDFText_MarkedContent CPDF_TextPage::PreMarkedContent(PDFTEXT_Obj Obj) {
  CPDF_TextObject* pTextObj = Obj.m_pTextObj;
  if (!pTextObj->m_ContentMark)
    return FPDFText_MarkedContent::Pass;

  int nContentMark = pTextObj->m_ContentMark.CountItems();
  if (nContentMark < 1)
    return FPDFText_MarkedContent::Pass;

  CFX_WideString actText;
  bool bExist = false;
  CPDF_Dictionary* pDict = nullptr;
  int n = 0;
  for (n = 0; n < nContentMark; n++) {
    const CPDF_ContentMarkItem& item = pTextObj->m_ContentMark.GetItem(n);
    pDict = item.GetParam();
    if (!pDict)
      continue;
    CPDF_String* temp = ToString(pDict->GetObjectFor("ActualText"));
    if (temp) {
      bExist = true;
      actText = temp->GetUnicodeText();
    }
  }
  if (!bExist)
    return FPDFText_MarkedContent::Pass;

  if (m_pPreTextObj && m_pPreTextObj->m_ContentMark &&
      m_pPreTextObj->m_ContentMark.CountItems() == n &&
      pDict == m_pPreTextObj->m_ContentMark.GetItem(n - 1).GetParam()) {
    return FPDFText_MarkedContent::Done;
  }

  FX_STRSIZE nItems = actText.GetLength();
  if (nItems < 1)
    return FPDFText_MarkedContent::Pass;

  CPDF_Font* pFont = pTextObj->GetFont();
  bExist = false;
  for (FX_STRSIZE i = 0; i < nItems; i++) {
    if (pFont->CharCodeFromUnicode(actText.GetAt(i)) !=
        CPDF_Font::kInvalidCharCode) {
      bExist = true;
      break;
    }
  }
  if (!bExist)
    return FPDFText_MarkedContent::Pass;

  bExist = false;
  for (FX_STRSIZE i = 0; i < nItems; i++) {
    FX_WCHAR wChar = actText.GetAt(i);
    if ((wChar > 0x80 && wChar < 0xFFFD) || (wChar <= 0x80 && isprint(wChar))) {
      bExist = true;
      break;
    }
  }
  if (!bExist)
    return FPDFText_MarkedContent::Done;

  return FPDFText_MarkedContent::Delay;
}

void CPDF_TextPage::ProcessMarkedContent(PDFTEXT_Obj Obj) {
  CPDF_TextObject* pTextObj = Obj.m_pTextObj;
  if (!pTextObj->m_ContentMark)
    return;

  int nContentMark = pTextObj->m_ContentMark.CountItems();
  if (nContentMark < 1)
    return;

  CFX_WideString actText;
  for (int n = 0; n < nContentMark; n++) {
    const CPDF_ContentMarkItem& item = pTextObj->m_ContentMark.GetItem(n);
    CPDF_Dictionary* pDict = item.GetParam();
    if (pDict)
      actText = pDict->GetUnicodeTextFor("ActualText");
  }
  FX_STRSIZE nItems = actText.GetLength();
  if (nItems < 1)
    return;

  CPDF_Font* pFont = pTextObj->GetFont();
  CFX_Matrix matrix = pTextObj->GetTextMatrix();
  matrix.Concat(Obj.m_formMatrix);

  for (FX_STRSIZE k = 0; k < nItems; k++) {
    FX_WCHAR wChar = actText.GetAt(k);
    if (wChar <= 0x80 && !isprint(wChar))
      wChar = 0x20;
    if (wChar >= 0xFFFD)
      continue;

    PAGECHAR_INFO charinfo;
    charinfo.m_Origin = pTextObj->GetPos();
    charinfo.m_Index = m_TextBuf.GetLength();
    charinfo.m_Unicode = wChar;
    charinfo.m_CharCode = pFont->CharCodeFromUnicode(wChar);
    charinfo.m_Flag = FPDFTEXT_CHAR_PIECE;
    charinfo.m_pTextObj = pTextObj;
    charinfo.m_CharBox = pTextObj->GetRect();
    charinfo.m_Matrix = matrix;
    m_TempTextBuf.AppendChar(wChar);
    m_TempCharList.push_back(charinfo);
  }
}

void CPDF_TextPage::FindPreviousTextObject() {
  if (m_TempCharList.empty() && m_CharList.empty())
    return;

  PAGECHAR_INFO preChar =
      m_TempCharList.empty() ? m_CharList.back() : m_TempCharList.back();

  if (preChar.m_pTextObj)
    m_pPreTextObj = preChar.m_pTextObj;
}

void CPDF_TextPage::SwapTempTextBuf(int32_t iCharListStartAppend,
                                    int32_t iBufStartAppend) {
  int32_t i = iCharListStartAppend;
  int32_t j = pdfium::CollectionSize<int32_t>(m_TempCharList) - 1;
  for (; i < j; i++, j--) {
    std::swap(m_TempCharList[i], m_TempCharList[j]);
    std::swap(m_TempCharList[i].m_Index, m_TempCharList[j].m_Index);
  }
  FX_WCHAR* pTempBuffer = m_TempTextBuf.GetBuffer();
  i = iBufStartAppend;
  j = m_TempTextBuf.GetLength() - 1;
  for (; i < j; i++, j--)
    std::swap(pTempBuffer[i], pTempBuffer[j]);
}

bool CPDF_TextPage::IsRightToLeft(const CPDF_TextObject* pTextObj,
                                  const CPDF_Font* pFont,
                                  int nItems) const {
  CFX_WideString str;
  for (int32_t i = 0; i < nItems; i++) {
    CPDF_TextObjectItem item;
    pTextObj->GetItemInfo(i, &item);
    if (item.m_CharCode == static_cast<uint32_t>(-1))
      continue;
    CFX_WideString wstrItem = pFont->UnicodeFromCharCode(item.m_CharCode);
    FX_WCHAR wChar = wstrItem.GetAt(0);
    if ((wstrItem.IsEmpty() || wChar == 0) && item.m_CharCode)
      wChar = (FX_WCHAR)item.m_CharCode;
    if (wChar)
      str += wChar;
  }
  return CFX_BidiString(str).OverallDirection() == CFX_BidiChar::RIGHT;
}

void CPDF_TextPage::ProcessTextObject(PDFTEXT_Obj Obj) {
  CPDF_TextObject* pTextObj = Obj.m_pTextObj;
  if (FXSYS_fabs(pTextObj->m_Right - pTextObj->m_Left) < 0.01f)
    return;
  CFX_Matrix formMatrix = Obj.m_formMatrix;
  CPDF_Font* pFont = pTextObj->GetFont();
  CFX_Matrix matrix = pTextObj->GetTextMatrix();
  matrix.Concat(formMatrix);

  FPDFText_MarkedContent ePreMKC = PreMarkedContent(Obj);
  if (ePreMKC == FPDFText_MarkedContent::Done) {
    m_pPreTextObj = pTextObj;
    m_perMatrix = formMatrix;
    return;
  }
  GenerateCharacter result = GenerateCharacter::None;
  if (m_pPreTextObj) {
    result = ProcessInsertObject(pTextObj, formMatrix);
    if (result == GenerateCharacter::LineBreak)
      m_CurlineRect = Obj.m_pTextObj->GetRect();
    else
      m_CurlineRect.Union(Obj.m_pTextObj->GetRect());

    switch (result) {
      case GenerateCharacter::None:
        break;
      case GenerateCharacter::Space: {
        PAGECHAR_INFO generateChar;
        if (GenerateCharInfo(TEXT_SPACE_CHAR, generateChar)) {
          if (!formMatrix.IsIdentity())
            generateChar.m_Matrix = formMatrix;
          m_TempTextBuf.AppendChar(TEXT_SPACE_CHAR);
          m_TempCharList.push_back(generateChar);
        }
        break;
      }
      case GenerateCharacter::LineBreak:
        CloseTempLine();
        if (m_TextBuf.GetSize()) {
          AppendGeneratedCharacter(TEXT_RETURN_CHAR, formMatrix);
          AppendGeneratedCharacter(TEXT_LINEFEED_CHAR, formMatrix);
        }
        break;
      case GenerateCharacter::Hyphen:
        if (pTextObj->CountChars() == 1) {
          CPDF_TextObjectItem item;
          pTextObj->GetCharInfo(0, &item);
          CFX_WideString wstrItem =
              pTextObj->GetFont()->UnicodeFromCharCode(item.m_CharCode);
          if (wstrItem.IsEmpty())
            wstrItem += (FX_WCHAR)item.m_CharCode;
          FX_WCHAR curChar = wstrItem.GetAt(0);
          if (curChar == 0x2D || curChar == 0xAD)
            return;
        }
        while (m_TempTextBuf.GetSize() > 0 &&
               m_TempTextBuf.AsStringC().GetAt(m_TempTextBuf.GetLength() - 1) ==
                   0x20) {
          m_TempTextBuf.Delete(m_TempTextBuf.GetLength() - 1, 1);
          m_TempCharList.pop_back();
        }
        PAGECHAR_INFO* charinfo = &m_TempCharList.back();
        m_TempTextBuf.Delete(m_TempTextBuf.GetLength() - 1, 1);
        charinfo->m_Unicode = 0x2;
        charinfo->m_Flag = FPDFTEXT_CHAR_HYPHEN;
        m_TempTextBuf.AppendChar(0xfffe);
        break;
    }
  } else {
    m_CurlineRect = Obj.m_pTextObj->GetRect();
  }

  if (ePreMKC == FPDFText_MarkedContent::Delay) {
    ProcessMarkedContent(Obj);
    m_pPreTextObj = pTextObj;
    m_perMatrix = formMatrix;
    return;
  }
  m_pPreTextObj = pTextObj;
  m_perMatrix = formMatrix;
  int nItems = pTextObj->CountItems();
  FX_FLOAT baseSpace = CalculateBaseSpace(pTextObj, matrix);

  const bool bR2L = IsRightToLeft(pTextObj, pFont, nItems);
  const bool bIsBidiAndMirrorInverse =
      bR2L && (matrix.a * matrix.d - matrix.b * matrix.c) < 0;
  int32_t iBufStartAppend = m_TempTextBuf.GetLength();
  int32_t iCharListStartAppend =
      pdfium::CollectionSize<int32_t>(m_TempCharList);

  FX_FLOAT spacing = 0;
  for (int i = 0; i < nItems; i++) {
    CPDF_TextObjectItem item;
    PAGECHAR_INFO charinfo;
    pTextObj->GetItemInfo(i, &item);
    if (item.m_CharCode == static_cast<uint32_t>(-1)) {
      CFX_WideString str = m_TempTextBuf.MakeString();
      if (str.IsEmpty())
        str = m_TextBuf.AsStringC();
      if (str.IsEmpty() || str.GetAt(str.GetLength() - 1) == TEXT_SPACE_CHAR)
        continue;

      FX_FLOAT fontsize_h = pTextObj->m_TextState.GetFontSizeH();
      spacing = -fontsize_h * item.m_Origin.x / 1000;
      continue;
    }
    FX_FLOAT charSpace = pTextObj->m_TextState.GetCharSpace();
    if (charSpace > 0.001)
      spacing += matrix.TransformDistance(charSpace);
    else if (charSpace < -0.001)
      spacing -= matrix.TransformDistance(FXSYS_fabs(charSpace));
    spacing -= baseSpace;
    if (spacing && i > 0) {
      int last_width = 0;
      FX_FLOAT fontsize_h = pTextObj->m_TextState.GetFontSizeH();
      uint32_t space_charcode = pFont->CharCodeFromUnicode(' ');
      FX_FLOAT threshold = 0;
      if (space_charcode != CPDF_Font::kInvalidCharCode)
        threshold = fontsize_h * pFont->GetCharWidthF(space_charcode) / 1000;
      if (threshold > fontsize_h / 3)
        threshold = 0;
      else
        threshold /= 2;
      if (threshold == 0) {
        threshold = fontsize_h;
        int this_width = FXSYS_abs(GetCharWidth(item.m_CharCode, pFont));
        threshold = this_width > last_width ? (FX_FLOAT)this_width
                                            : (FX_FLOAT)last_width;
        threshold = NormalizeThreshold(threshold);
        threshold = fontsize_h * threshold / 1000;
      }
      if (threshold && (spacing && spacing >= threshold)) {
        charinfo.m_Unicode = TEXT_SPACE_CHAR;
        charinfo.m_Flag = FPDFTEXT_CHAR_GENERATED;
        charinfo.m_pTextObj = pTextObj;
        charinfo.m_Index = m_TextBuf.GetLength();
        m_TempTextBuf.AppendChar(TEXT_SPACE_CHAR);
        charinfo.m_CharCode = CPDF_Font::kInvalidCharCode;
        charinfo.m_Matrix = formMatrix;
        charinfo.m_Origin = matrix.Transform(item.m_Origin);
        charinfo.m_CharBox =
            CFX_FloatRect(charinfo.m_Origin.x, charinfo.m_Origin.y,
                          charinfo.m_Origin.x, charinfo.m_Origin.y);
        m_TempCharList.push_back(charinfo);
      }
      if (item.m_CharCode == CPDF_Font::kInvalidCharCode)
        continue;
    }
    spacing = 0;
    CFX_WideString wstrItem = pFont->UnicodeFromCharCode(item.m_CharCode);
    bool bNoUnicode = false;
    if (wstrItem.IsEmpty() && item.m_CharCode) {
      wstrItem += static_cast<FX_WCHAR>(item.m_CharCode);
      bNoUnicode = true;
    }
    charinfo.m_Index = -1;
    charinfo.m_CharCode = item.m_CharCode;
    if (bNoUnicode)
      charinfo.m_Flag = FPDFTEXT_CHAR_UNUNICODE;
    else
      charinfo.m_Flag = FPDFTEXT_CHAR_NORMAL;

    charinfo.m_pTextObj = pTextObj;
    charinfo.m_Origin = matrix.Transform(item.m_Origin);

    FX_RECT rect =
        charinfo.m_pTextObj->GetFont()->GetCharBBox(charinfo.m_CharCode);
    charinfo.m_CharBox.top =
        rect.top * pTextObj->GetFontSize() / 1000 + item.m_Origin.y;
    charinfo.m_CharBox.left =
        rect.left * pTextObj->GetFontSize() / 1000 + item.m_Origin.x;
    charinfo.m_CharBox.right =
        rect.right * pTextObj->GetFontSize() / 1000 + item.m_Origin.x;
    charinfo.m_CharBox.bottom =
        rect.bottom * pTextObj->GetFontSize() / 1000 + item.m_Origin.y;
    if (fabsf(charinfo.m_CharBox.top - charinfo.m_CharBox.bottom) < 0.01f) {
      charinfo.m_CharBox.top =
          charinfo.m_CharBox.bottom + pTextObj->GetFontSize();
    }
    if (fabsf(charinfo.m_CharBox.right - charinfo.m_CharBox.left) < 0.01f) {
      charinfo.m_CharBox.right =
          charinfo.m_CharBox.left + pTextObj->GetCharWidth(charinfo.m_CharCode);
    }
    matrix.TransformRect(charinfo.m_CharBox);
    charinfo.m_Matrix = matrix;
    if (wstrItem.IsEmpty()) {
      charinfo.m_Unicode = 0;
      m_TempCharList.push_back(charinfo);
      m_TempTextBuf.AppendChar(0xfffe);
      continue;
    } else {
      int nTotal = wstrItem.GetLength();
      bool bDel = false;
      const int count =
          std::min(pdfium::CollectionSize<int>(m_TempCharList), 7);
      FX_FLOAT threshold = charinfo.m_Matrix.TransformXDistance(
          (FX_FLOAT)TEXT_CHARRATIO_GAPDELTA * pTextObj->GetFontSize());
      for (int n = pdfium::CollectionSize<int>(m_TempCharList);
           n > pdfium::CollectionSize<int>(m_TempCharList) - count; n--) {
        const PAGECHAR_INFO& charinfo1 = m_TempCharList[n - 1];
        CFX_PointF diff = charinfo1.m_Origin - charinfo.m_Origin;
        if (charinfo1.m_CharCode == charinfo.m_CharCode &&
            charinfo1.m_pTextObj->GetFont() == charinfo.m_pTextObj->GetFont() &&
            FXSYS_fabs(diff.x) < threshold && FXSYS_fabs(diff.y) < threshold) {
          bDel = true;
          break;
        }
      }
      if (!bDel) {
        for (int nIndex = 0; nIndex < nTotal; nIndex++) {
          charinfo.m_Unicode = wstrItem.GetAt(nIndex);
          if (charinfo.m_Unicode) {
            charinfo.m_Index = m_TextBuf.GetLength();
            m_TempTextBuf.AppendChar(charinfo.m_Unicode);
          } else {
            m_TempTextBuf.AppendChar(0xfffe);
          }
          m_TempCharList.push_back(charinfo);
        }
      } else if (i == 0) {
        CFX_WideString str = m_TempTextBuf.MakeString();
        if (!str.IsEmpty() &&
            str.GetAt(str.GetLength() - 1) == TEXT_SPACE_CHAR) {
          m_TempTextBuf.Delete(m_TempTextBuf.GetLength() - 1, 1);
          m_TempCharList.pop_back();
        }
      }
    }
  }
  if (bIsBidiAndMirrorInverse)
    SwapTempTextBuf(iCharListStartAppend, iBufStartAppend);
}

CPDF_TextPage::TextOrientation CPDF_TextPage::GetTextObjectWritingMode(
    const CPDF_TextObject* pTextObj) const {
  int32_t nChars = pTextObj->CountChars();
  if (nChars == 1)
    return m_TextlineDir;

  CPDF_TextObjectItem first, last;
  pTextObj->GetCharInfo(0, &first);
  pTextObj->GetCharInfo(nChars - 1, &last);

  CFX_Matrix textMatrix = pTextObj->GetTextMatrix();
  first.m_Origin = textMatrix.Transform(first.m_Origin);
  last.m_Origin = textMatrix.Transform(last.m_Origin);

  FX_FLOAT dX = FXSYS_fabs(last.m_Origin.x - first.m_Origin.x);
  FX_FLOAT dY = FXSYS_fabs(last.m_Origin.y - first.m_Origin.y);
  if (dX <= 0.0001f && dY <= 0.0001f)
    return TextOrientation::Unknown;

  CFX_VectorF v(dX, dY);
  v.Normalize();
  if (v.y <= 0.0872f)
    return v.x <= 0.0872f ? m_TextlineDir : TextOrientation::Horizontal;

  if (v.x <= 0.0872f)
    return TextOrientation::Vertical;

  return m_TextlineDir;
}

bool CPDF_TextPage::IsHyphen(FX_WCHAR curChar) {
  CFX_WideString strCurText = m_TempTextBuf.MakeString();
  if (strCurText.IsEmpty())
    strCurText = m_TextBuf.AsStringC();
  FX_STRSIZE nCount = strCurText.GetLength();
  int nIndex = nCount - 1;
  FX_WCHAR wcTmp = strCurText.GetAt(nIndex);
  while (wcTmp == 0x20 && nIndex <= nCount - 1 && nIndex >= 0)
    wcTmp = strCurText.GetAt(--nIndex);
  if (0x2D == wcTmp || 0xAD == wcTmp) {
    if (--nIndex > 0) {
      FX_WCHAR preChar = strCurText.GetAt((nIndex));
      if (((preChar >= L'A' && preChar <= L'Z') ||
           (preChar >= L'a' && preChar <= L'z')) &&
          ((curChar >= L'A' && curChar <= L'Z') ||
           (curChar >= L'a' && curChar <= L'z'))) {
        return true;
      }
    }
    const PAGECHAR_INFO* preInfo;
    if (!m_TempCharList.empty())
      preInfo = &m_TempCharList.back();
    else if (!m_CharList.empty())
      preInfo = &m_CharList.back();
    else
      return false;
    if (FPDFTEXT_CHAR_PIECE == preInfo->m_Flag &&
        (0xAD == preInfo->m_Unicode || 0x2D == preInfo->m_Unicode)) {
      return true;
    }
  }
  return false;
}

CPDF_TextPage::GenerateCharacter CPDF_TextPage::ProcessInsertObject(
    const CPDF_TextObject* pObj,
    const CFX_Matrix& formMatrix) {
  FindPreviousTextObject();
  TextOrientation WritingMode = GetTextObjectWritingMode(pObj);
  if (WritingMode == TextOrientation::Unknown)
    WritingMode = GetTextObjectWritingMode(m_pPreTextObj);

  CFX_FloatRect this_rect = pObj->GetRect();
  CFX_FloatRect prev_rect = m_pPreTextObj->GetRect();
  CPDF_TextObjectItem PrevItem;
  CPDF_TextObjectItem item;
  int nItem = m_pPreTextObj->CountItems();
  m_pPreTextObj->GetItemInfo(nItem - 1, &PrevItem);
  pObj->GetItemInfo(0, &item);
  CFX_WideString wstrItem =
      pObj->GetFont()->UnicodeFromCharCode(item.m_CharCode);
  if (wstrItem.IsEmpty())
    wstrItem += static_cast<FX_WCHAR>(item.m_CharCode);
  FX_WCHAR curChar = wstrItem.GetAt(0);
  if (WritingMode == TextOrientation::Horizontal) {
    if (this_rect.Height() > 4.5 && prev_rect.Height() > 4.5) {
      FX_FLOAT top =
          this_rect.top < prev_rect.top ? this_rect.top : prev_rect.top;
      FX_FLOAT bottom = this_rect.bottom > prev_rect.bottom ? this_rect.bottom
                                                            : prev_rect.bottom;
      if (bottom >= top) {
        return IsHyphen(curChar) ? GenerateCharacter::Hyphen
                                 : GenerateCharacter::LineBreak;
      }
    }
  } else if (WritingMode == TextOrientation::Vertical) {
    if (this_rect.Width() > pObj->GetFontSize() * 0.1f &&
        prev_rect.Width() > m_pPreTextObj->GetFontSize() * 0.1f) {
      FX_FLOAT left = this_rect.left > m_CurlineRect.left ? this_rect.left
                                                          : m_CurlineRect.left;
      FX_FLOAT right = this_rect.right < m_CurlineRect.right
                           ? this_rect.right
                           : m_CurlineRect.right;
      if (right <= left) {
        return IsHyphen(curChar) ? GenerateCharacter::Hyphen
                                 : GenerateCharacter::LineBreak;
      }
    }
  }

  FX_FLOAT last_pos = PrevItem.m_Origin.x;
  int nLastWidth = GetCharWidth(PrevItem.m_CharCode, m_pPreTextObj->GetFont());
  FX_FLOAT last_width = nLastWidth * m_pPreTextObj->GetFontSize() / 1000;
  last_width = FXSYS_fabs(last_width);
  int nThisWidth = GetCharWidth(item.m_CharCode, pObj->GetFont());
  FX_FLOAT this_width = nThisWidth * pObj->GetFontSize() / 1000;
  this_width = FXSYS_fabs(this_width);
  FX_FLOAT threshold =
      last_width > this_width ? last_width / 4 : this_width / 4;

  CFX_Matrix prev_matrix = m_pPreTextObj->GetTextMatrix();
  prev_matrix.Concat(m_perMatrix);

  CFX_Matrix prev_reverse;
  prev_reverse.SetReverse(prev_matrix);

  CFX_PointF pos = prev_reverse.Transform(formMatrix.Transform(pObj->GetPos()));
  if (last_width < this_width)
    threshold = prev_reverse.TransformDistance(threshold);

  bool bNewline = false;
  if (WritingMode == TextOrientation::Horizontal) {
    CFX_FloatRect rect1(m_pPreTextObj->m_Left, pObj->m_Bottom,
                        m_pPreTextObj->m_Right, pObj->m_Top);
    CFX_FloatRect rect2 = m_pPreTextObj->GetRect();
    CFX_FloatRect rect3 = rect1;
    rect1.Intersect(rect2);
    if ((rect1.IsEmpty() && rect2.Height() > 5 && rect3.Height() > 5) ||
        ((pos.y > threshold * 2 || pos.y < threshold * -3) &&
         (FXSYS_fabs(pos.y) < 1 ? FXSYS_fabs(pos.x) < FXSYS_fabs(pos.y)
                                : true))) {
      bNewline = true;
      if (nItem > 1) {
        CPDF_TextObjectItem tempItem;
        m_pPreTextObj->GetItemInfo(0, &tempItem);
        CFX_Matrix m = m_pPreTextObj->GetTextMatrix();
        if (PrevItem.m_Origin.x > tempItem.m_Origin.x &&
            m_DisplayMatrix.a > 0.9 && m_DisplayMatrix.b < 0.1 &&
            m_DisplayMatrix.c < 0.1 && m_DisplayMatrix.d < -0.9 && m.b < 0.1 &&
            m.c < 0.1) {
          CFX_FloatRect re(0, m_pPreTextObj->m_Bottom, 1000,
                           m_pPreTextObj->m_Top);
          if (re.Contains(pObj->GetPos())) {
            bNewline = false;
          } else {
            CFX_FloatRect rect(0, pObj->m_Bottom, 1000, pObj->m_Top);
            if (rect.Contains(m_pPreTextObj->GetPos()))
              bNewline = false;
          }
        }
      }
    }
  }
  if (bNewline) {
    return IsHyphen(curChar) ? GenerateCharacter::Hyphen
                             : GenerateCharacter::LineBreak;
  }

  int32_t nChars = pObj->CountChars();
  if (nChars == 1 && (0x2D == curChar || 0xAD == curChar) &&
      IsHyphen(curChar)) {
    return GenerateCharacter::Hyphen;
  }
  CFX_WideString PrevStr =
      m_pPreTextObj->GetFont()->UnicodeFromCharCode(PrevItem.m_CharCode);
  FX_WCHAR preChar = PrevStr.GetAt(PrevStr.GetLength() - 1);
  CFX_Matrix matrix = pObj->GetTextMatrix();
  matrix.Concat(formMatrix);

  threshold = (FX_FLOAT)(nLastWidth > nThisWidth ? nLastWidth : nThisWidth);
  threshold = threshold > 400
                  ? (threshold < 700
                         ? threshold / 4
                         : (threshold > 800 ? threshold / 6 : threshold / 5))
                  : (threshold / 2);
  if (nLastWidth >= nThisWidth) {
    threshold *= FXSYS_fabs(m_pPreTextObj->GetFontSize());
  } else {
    threshold *= FXSYS_fabs(pObj->GetFontSize());
    threshold = matrix.TransformDistance(threshold);
    threshold = prev_reverse.TransformDistance(threshold);
  }
  threshold /= 1000;
  if ((threshold < 1.4881 && threshold > 1.4879) ||
      (threshold < 1.39001 && threshold > 1.38999)) {
    threshold *= 1.5;
  }
  if (FXSYS_fabs(last_pos + last_width - pos.x) > threshold &&
      curChar != L' ' && preChar != L' ') {
    if (curChar != L' ' && preChar != L' ') {
      if ((pos.x - last_pos - last_width) > threshold ||
          (last_pos - pos.x - last_width) > threshold) {
        return GenerateCharacter::Space;
      }
      if (pos.x < 0 && (last_pos - pos.x - last_width) > threshold)
        return GenerateCharacter::Space;
      if ((pos.x - last_pos - last_width) > this_width ||
          (pos.x - last_pos - this_width) > last_width) {
        return GenerateCharacter::Space;
      }
    }
  }
  return GenerateCharacter::None;
}

bool CPDF_TextPage::IsSameTextObject(CPDF_TextObject* pTextObj1,
                                     CPDF_TextObject* pTextObj2) {
  if (!pTextObj1 || !pTextObj2)
    return false;

  CFX_FloatRect rcPreObj = pTextObj2->GetRect();
  CFX_FloatRect rcCurObj = pTextObj1->GetRect();
  if (rcPreObj.IsEmpty() && rcCurObj.IsEmpty()) {
    FX_FLOAT dbXdif = FXSYS_fabs(rcPreObj.left - rcCurObj.left);
    size_t nCount = m_CharList.size();
    if (nCount >= 2) {
      PAGECHAR_INFO perCharTemp = m_CharList[nCount - 2];
      FX_FLOAT dbSpace = perCharTemp.m_CharBox.Width();
      if (dbXdif > dbSpace)
        return false;
    }
  }
  if (!rcPreObj.IsEmpty() || !rcCurObj.IsEmpty()) {
    rcPreObj.Intersect(rcCurObj);
    if (rcPreObj.IsEmpty())
      return false;
    if (FXSYS_fabs(rcPreObj.Width() - rcCurObj.Width()) >
        rcCurObj.Width() / 2) {
      return false;
    }
    if (pTextObj2->GetFontSize() != pTextObj1->GetFontSize())
      return false;
  }
  int nPreCount = pTextObj2->CountItems();
  int nCurCount = pTextObj1->CountItems();
  if (nPreCount != nCurCount)
    return false;
  // If both objects have no items, consider them same.
  if (!nPreCount)
    return true;

  CPDF_TextObjectItem itemPer;
  CPDF_TextObjectItem itemCur;
  for (int i = 0; i < nPreCount; i++) {
    pTextObj2->GetItemInfo(i, &itemPer);
    pTextObj1->GetItemInfo(i, &itemCur);
    if (itemCur.m_CharCode != itemPer.m_CharCode)
      return false;
  }

  CFX_PointF diff = pTextObj1->GetPos() - pTextObj2->GetPos();
  FX_FLOAT font_size = pTextObj2->GetFontSize();
  FX_FLOAT char_size = GetCharWidth(itemPer.m_CharCode, pTextObj2->GetFont());
  FX_FLOAT max_pre_size =
      std::max(std::max(rcPreObj.Height(), rcPreObj.Width()), font_size);
  if (FXSYS_fabs(diff.x) > char_size * font_size / 1000 * 0.9 ||
      FXSYS_fabs(diff.y) > max_pre_size / 8) {
    return false;
  }
  return true;
}

bool CPDF_TextPage::IsSameAsPreTextObject(
    CPDF_TextObject* pTextObj,
    const CPDF_PageObjectList* pObjList,
    CPDF_PageObjectList::const_iterator iter) {
  int i = 0;
  while (i < 5 && iter != pObjList->begin()) {
    --iter;
    CPDF_PageObject* pOtherObj = iter->get();
    if (pOtherObj == pTextObj || !pOtherObj->IsText())
      continue;
    if (IsSameTextObject(pOtherObj->AsText(), pTextObj))
      return true;
    ++i;
  }
  return false;
}

bool CPDF_TextPage::GenerateCharInfo(FX_WCHAR unicode, PAGECHAR_INFO& info) {
  const PAGECHAR_INFO* preChar;
  if (!m_TempCharList.empty())
    preChar = &m_TempCharList.back();
  else if (!m_CharList.empty())
    preChar = &m_CharList.back();
  else
    return false;

  info.m_Index = m_TextBuf.GetLength();
  info.m_Unicode = unicode;
  info.m_pTextObj = nullptr;
  info.m_CharCode = CPDF_Font::kInvalidCharCode;
  info.m_Flag = FPDFTEXT_CHAR_GENERATED;

  int preWidth = 0;
  if (preChar->m_pTextObj && preChar->m_CharCode != -1) {
    preWidth =
        GetCharWidth(preChar->m_CharCode, preChar->m_pTextObj->GetFont());
  }

  FX_FLOAT fFontSize = preChar->m_pTextObj ? preChar->m_pTextObj->GetFontSize()
                                           : preChar->m_CharBox.Height();
  if (!fFontSize)
    fFontSize = kDefaultFontSize;

  info.m_Origin = CFX_PointF(
      preChar->m_Origin.x + preWidth * (fFontSize) / 1000, preChar->m_Origin.y);
  info.m_CharBox = CFX_FloatRect(info.m_Origin.x, info.m_Origin.y,
                                 info.m_Origin.x, info.m_Origin.y);
  return true;
}

bool CPDF_TextPage::IsRectIntersect(const CFX_FloatRect& rect1,
                                    const CFX_FloatRect& rect2) {
  CFX_FloatRect rect = rect1;
  rect.Intersect(rect2);
  return !rect.IsEmpty();
}