yaze/src/app/gui/modules/text_editor.cc

#include "text_editor.h"

#include <algorithm>
#include <chrono>
#include <cmath>
#include <regex>
#include <string>

#define IMGUI_DEFINE_MATH_OPERATORS
#include "imgui.h"  // for imGui::GetCurrentWindow()

// TODO
// - multiline comments vs single-line: latter is blocking start of a ML

template <class InputIt1, class InputIt2, class BinaryPredicate>
bool equals(InputIt1 first1, InputIt1 last1, InputIt2 first2, InputIt2 last2,
            BinaryPredicate p) {
  for (; first1 != last1 && first2 != last2; ++first1, ++first2) {
    if (!p(*first1, *first2)) return false;
  }
  return first1 == last1 && first2 == last2;
}

TextEditor::TextEditor()
    : mLineSpacing(1.0f),
      mUndoIndex(0),
      mTabSize(4),
      mOverwrite(false),
      mReadOnly(false),
      mWithinRender(false),
      mScrollToCursor(false),
      mScrollToTop(false),
      mTextChanged(false),
      mColorizerEnabled(true),
      mTextStart(20.0f),
      mLeftMargin(10),
      mCursorPositionChanged(false),
      mColorRangeMin(0),
      mColorRangeMax(0),
      mSelectionMode(SelectionMode::Normal),
      mCheckComments(true),
      mLastClick(-1.0f),
      mHandleKeyboardInputs(true),
      mHandleMouseInputs(true),
      mIgnoreImGuiChild(false),
      mShowWhitespaces(true),
      mStartTime(std::chrono::duration_cast<std::chrono::milliseconds>(
                     std::chrono::system_clock::now().time_since_epoch())
                     .count()) {
  SetPalette(GetDarkPalette());
  SetLanguageDefinition(LanguageDefinition::HLSL());
  mLines.push_back(Line());
}

TextEditor::~TextEditor() {}

void TextEditor::SetLanguageDefinition(const LanguageDefinition& aLanguageDef) {
  mLanguageDefinition = aLanguageDef;
  mRegexList.clear();

  for (auto& r : mLanguageDefinition.mTokenRegexStrings)
    mRegexList.push_back(std::make_pair(
        std::regex(r.first, std::regex_constants::optimize), r.second));

  Colorize();
}

void TextEditor::SetPalette(const Palette& aValue) { mPaletteBase = aValue; }

std::string TextEditor::GetText(const Coordinates& aStart,
                                const Coordinates& aEnd) const {
  std::string result;

  auto lstart = aStart.mLine;
  auto lend = aEnd.mLine;
  auto istart = GetCharacterIndex(aStart);
  auto iend = GetCharacterIndex(aEnd);
  size_t s = 0;

  for (size_t i = lstart; i < lend; i++) s += mLines[i].size();

  result.reserve(s + s / 8);

  while (istart < iend || lstart < lend) {
    if (lstart >= (int)mLines.size()) break;

    auto& line = mLines[lstart];
    if (istart < (int)line.size()) {
      result += line[istart].mChar;
      istart++;
    } else {
      istart = 0;
      ++lstart;
      result += '\n';
    }
  }

  return result;
}

TextEditor::Coordinates TextEditor::GetActualCursorCoordinates() const {
  return SanitizeCoordinates(mState.mCursorPosition);
}

TextEditor::Coordinates TextEditor::SanitizeCoordinates(
    const Coordinates& aValue) const {
  auto line = aValue.mLine;
  auto column = aValue.mColumn;
  if (line >= (int)mLines.size()) {
    if (mLines.empty()) {
      line = 0;
      column = 0;
    } else {
      line = (int)mLines.size() - 1;
      column = GetLineMaxColumn(line);
    }
    return Coordinates(line, column);
  } else {
    column = mLines.empty() ? 0 : std::min(column, GetLineMaxColumn(line));
    return Coordinates(line, column);
  }
}

// https://en.wikipedia.org/wiki/UTF-8
// We assume that the char is a standalone character (<128) or a leading byte of
// an UTF-8 code sequence (non-10xxxxxx code)
static int UTF8CharLength(TextEditor::Char c) {
  if ((c & 0xFE) == 0xFC) return 6;
  if ((c & 0xFC) == 0xF8) return 5;
  if ((c & 0xF8) == 0xF0)
    return 4;
  else if ((c & 0xF0) == 0xE0)
    return 3;
  else if ((c & 0xE0) == 0xC0)
    return 2;
  return 1;
}

// "Borrowed" from ImGui source
static inline int ImTextCharToUtf8(char* buf, int buf_size, unsigned int c) {
  if (c < 0x80) {
    buf[0] = (char)c;
    return 1;
  }
  if (c < 0x800) {
    if (buf_size < 2) return 0;
    buf[0] = (char)(0xc0 + (c >> 6));
    buf[1] = (char)(0x80 + (c & 0x3f));
    return 2;
  }
  if (c >= 0xdc00 && c < 0xe000) {
    return 0;
  }
  if (c >= 0xd800 && c < 0xdc00) {
    if (buf_size < 4) return 0;
    buf[0] = (char)(0xf0 + (c >> 18));
    buf[1] = (char)(0x80 + ((c >> 12) & 0x3f));
    buf[2] = (char)(0x80 + ((c >> 6) & 0x3f));
    buf[3] = (char)(0x80 + ((c) & 0x3f));
    return 4;
  }
  // else if (c < 0x10000)
  {
    if (buf_size < 3) return 0;
    buf[0] = (char)(0xe0 + (c >> 12));
    buf[1] = (char)(0x80 + ((c >> 6) & 0x3f));
    buf[2] = (char)(0x80 + ((c) & 0x3f));
    return 3;
  }
}

void TextEditor::Advance(Coordinates& aCoordinates) const {
  if (aCoordinates.mLine < (int)mLines.size()) {
    auto& line = mLines[aCoordinates.mLine];
    auto cindex = GetCharacterIndex(aCoordinates);

    if (cindex + 1 < (int)line.size()) {
      auto delta = UTF8CharLength(line[cindex].mChar);
      cindex = std::min(cindex + delta, (int)line.size() - 1);
    } else {
      ++aCoordinates.mLine;
      cindex = 0;
    }
    aCoordinates.mColumn = GetCharacterColumn(aCoordinates.mLine, cindex);
  }
}

void TextEditor::DeleteRange(const Coordinates& aStart,
                             const Coordinates& aEnd) {
  assert(aEnd >= aStart);
  assert(!mReadOnly);

  // printf("D(%d.%d)-(%d.%d)\n", aStart.mLine, aStart.mColumn, aEnd.mLine,
  // aEnd.mColumn);

  if (aEnd == aStart) return;

  auto start = GetCharacterIndex(aStart);
  auto end = GetCharacterIndex(aEnd);

  if (aStart.mLine == aEnd.mLine) {
    auto& line = mLines[aStart.mLine];
    auto n = GetLineMaxColumn(aStart.mLine);
    if (aEnd.mColumn >= n)
      line.erase(line.begin() + start, line.end());
    else
      line.erase(line.begin() + start, line.begin() + end);
  } else {
    auto& firstLine = mLines[aStart.mLine];
    auto& lastLine = mLines[aEnd.mLine];

    firstLine.erase(firstLine.begin() + start, firstLine.end());
    lastLine.erase(lastLine.begin(), lastLine.begin() + end);

    if (aStart.mLine < aEnd.mLine)
      firstLine.insert(firstLine.end(), lastLine.begin(), lastLine.end());

    if (aStart.mLine < aEnd.mLine) RemoveLine(aStart.mLine + 1, aEnd.mLine + 1);
  }

  mTextChanged = true;
}

int TextEditor::InsertTextAt(Coordinates& /* inout */ aWhere,
                             const char* aValue) {
  assert(!mReadOnly);

  int cindex = GetCharacterIndex(aWhere);
  int totalLines = 0;
  while (*aValue != '\0') {
    assert(!mLines.empty());

    if (*aValue == '\r') {
      // skip
      ++aValue;
    } else if (*aValue == '\n') {
      if (cindex < (int)mLines[aWhere.mLine].size()) {
        auto& newLine = InsertLine(aWhere.mLine + 1);
        auto& line = mLines[aWhere.mLine];
        newLine.insert(newLine.begin(), line.begin() + cindex, line.end());
        line.erase(line.begin() + cindex, line.end());
      } else {
        InsertLine(aWhere.mLine + 1);
      }
      ++aWhere.mLine;
      aWhere.mColumn = 0;
      cindex = 0;
      ++totalLines;
      ++aValue;
    } else {
      auto& line = mLines[aWhere.mLine];
      auto d = UTF8CharLength(*aValue);
      while (d-- > 0 && *aValue != '\0')
        line.insert(line.begin() + cindex++,
                    Glyph(*aValue++, PaletteIndex::Default));
      ++aWhere.mColumn;
    }

    mTextChanged = true;
  }

  return totalLines;
}

void TextEditor::AddUndo(UndoRecord& aValue) {
  assert(!mReadOnly);
  // printf("AddUndo: (@%d.%d) +\'%s' [%d.%d .. %d.%d], -\'%s', [%d.%d .. %d.%d]
  // (@%d.%d)\n", 	aValue.mBefore.mCursorPosition.mLine,
  //aValue.mBefore.mCursorPosition.mColumn, 	aValue.mAdded.c_str(),
  //aValue.mAddedStart.mLine, aValue.mAddedStart.mColumn,
  //aValue.mAddedEnd.mLine, aValue.mAddedEnd.mColumn, 	aValue.mRemoved.c_str(),
  //aValue.mRemovedStart.mLine, aValue.mRemovedStart.mColumn,
  //aValue.mRemovedEnd.mLine, aValue.mRemovedEnd.mColumn,
  //	aValue.mAfter.mCursorPosition.mLine,
  //aValue.mAfter.mCursorPosition.mColumn
  //	);

  mUndoBuffer.resize((size_t)(mUndoIndex + 1));
  mUndoBuffer.back() = aValue;
  ++mUndoIndex;
}

TextEditor::Coordinates TextEditor::ScreenPosToCoordinates(
    const ImVec2& aPosition) const {
  ImVec2 origin = ImGui::GetCursorScreenPos();
  ImVec2 local(aPosition.x - origin.x, aPosition.y - origin.y);

  int lineNo = std::max(0, (int)floor(local.y / mCharAdvance.y));

  int columnCoord = 0;

  if (lineNo >= 0 && lineNo < (int)mLines.size()) {
    auto& line = mLines.at(lineNo);

    int columnIndex = 0;
    float columnX = 0.0f;

    while ((size_t)columnIndex < line.size()) {
      float columnWidth = 0.0f;

      if (line[columnIndex].mChar == '\t') {
        float spaceSize =
            ImGui::GetFont()
                ->CalcTextSizeA(ImGui::GetFontSize(), FLT_MAX, -1.0f, " ")
                .x;
        float oldX = columnX;
        float newColumnX = (1.0f + std::floor((1.0f + columnX) /
                                              (float(mTabSize) * spaceSize))) *
                           (float(mTabSize) * spaceSize);
        columnWidth = newColumnX - oldX;
        if (mTextStart + columnX + columnWidth * 0.5f > local.x) break;
        columnX = newColumnX;
        columnCoord = (columnCoord / mTabSize) * mTabSize + mTabSize;
        columnIndex++;
      } else {
        char buf[7];
        auto d = UTF8CharLength(line[columnIndex].mChar);
        int i = 0;
        while (i < 6 && d-- > 0) buf[i++] = line[columnIndex++].mChar;
        buf[i] = '\0';
        columnWidth =
            ImGui::GetFont()
                ->CalcTextSizeA(ImGui::GetFontSize(), FLT_MAX, -1.0f, buf)
                .x;
        if (mTextStart + columnX + columnWidth * 0.5f > local.x) break;
        columnX += columnWidth;
        columnCoord++;
      }
    }
  }

  return SanitizeCoordinates(Coordinates(lineNo, columnCoord));
}

TextEditor::Coordinates TextEditor::FindWordStart(
    const Coordinates& aFrom) const {
  Coordinates at = aFrom;
  if (at.mLine >= (int)mLines.size()) return at;

  auto& line = mLines[at.mLine];
  auto cindex = GetCharacterIndex(at);

  if (cindex >= (int)line.size()) return at;

  while (cindex > 0 && isspace(line[cindex].mChar)) --cindex;

  auto cstart = (PaletteIndex)line[cindex].mColorIndex;
  while (cindex > 0) {
    auto c = line[cindex].mChar;
    if ((c & 0xC0) != 0x80)  // not UTF code sequence 10xxxxxx
    {
      if (c <= 32 && isspace(c)) {
        cindex++;
        break;
      }
      if (cstart != (PaletteIndex)line[size_t(cindex - 1)].mColorIndex) break;
    }
    --cindex;
  }
  return Coordinates(at.mLine, GetCharacterColumn(at.mLine, cindex));
}

TextEditor::Coordinates TextEditor::FindWordEnd(
    const Coordinates& aFrom) const {
  Coordinates at = aFrom;
  if (at.mLine >= (int)mLines.size()) return at;

  auto& line = mLines[at.mLine];
  auto cindex = GetCharacterIndex(at);

  if (cindex >= (int)line.size()) return at;

  bool prevspace = (bool)isspace(line[cindex].mChar);
  auto cstart = (PaletteIndex)line[cindex].mColorIndex;
  while (cindex < (int)line.size()) {
    auto c = line[cindex].mChar;
    auto d = UTF8CharLength(c);
    if (cstart != (PaletteIndex)line[cindex].mColorIndex) break;

    if (prevspace != !!isspace(c)) {
      if (isspace(c))
        while (cindex < (int)line.size() && isspace(line[cindex].mChar))
          ++cindex;
      break;
    }
    cindex += d;
  }
  return Coordinates(aFrom.mLine, GetCharacterColumn(aFrom.mLine, cindex));
}

TextEditor::Coordinates TextEditor::FindNextWord(
    const Coordinates& aFrom) const {
  Coordinates at = aFrom;
  if (at.mLine >= (int)mLines.size()) return at;

  // skip to the next non-word character
  auto cindex = GetCharacterIndex(aFrom);
  bool isword = false;
  bool skip = false;
  if (cindex < (int)mLines[at.mLine].size()) {
    auto& line = mLines[at.mLine];
    isword = isalnum(line[cindex].mChar);
    skip = isword;
  }

  while (!isword || skip) {
    if (at.mLine >= mLines.size()) {
      auto l = std::max(0, (int)mLines.size() - 1);
      return Coordinates(l, GetLineMaxColumn(l));
    }

    auto& line = mLines[at.mLine];
    if (cindex < (int)line.size()) {
      isword = isalnum(line[cindex].mChar);

      if (isword && !skip)
        return Coordinates(at.mLine, GetCharacterColumn(at.mLine, cindex));

      if (!isword) skip = false;

      cindex++;
    } else {
      cindex = 0;
      ++at.mLine;
      skip = false;
      isword = false;
    }
  }

  return at;
}

int TextEditor::GetCharacterIndex(const Coordinates& aCoordinates) const {
  if (aCoordinates.mLine >= mLines.size()) return -1;
  auto& line = mLines[aCoordinates.mLine];
  int c = 0;
  int i = 0;
  for (; i < line.size() && c < aCoordinates.mColumn;) {
    if (line[i].mChar == '\t')
      c = (c / mTabSize) * mTabSize + mTabSize;
    else
      ++c;
    i += UTF8CharLength(line[i].mChar);
  }
  return i;
}

int TextEditor::GetCharacterColumn(int aLine, int aIndex) const {
  if (aLine >= mLines.size()) return 0;
  auto& line = mLines[aLine];
  int col = 0;
  int i = 0;
  while (i < aIndex && i < (int)line.size()) {
    auto c = line[i].mChar;
    i += UTF8CharLength(c);
    if (c == '\t')
      col = (col / mTabSize) * mTabSize + mTabSize;
    else
      col++;
  }
  return col;
}

int TextEditor::GetLineCharacterCount(int aLine) const {
  if (aLine >= mLines.size()) return 0;
  auto& line = mLines[aLine];
  int c = 0;
  for (unsigned i = 0; i < line.size(); c++) i += UTF8CharLength(line[i].mChar);
  return c;
}

int TextEditor::GetLineMaxColumn(int aLine) const {
  if (aLine >= mLines.size()) return 0;
  auto& line = mLines[aLine];
  int col = 0;
  for (unsigned i = 0; i < line.size();) {
    auto c = line[i].mChar;
    if (c == '\t')
      col = (col / mTabSize) * mTabSize + mTabSize;
    else
      col++;
    i += UTF8CharLength(c);
  }
  return col;
}

bool TextEditor::IsOnWordBoundary(const Coordinates& aAt) const {
  if (aAt.mLine >= (int)mLines.size() || aAt.mColumn == 0) return true;

  auto& line = mLines[aAt.mLine];
  auto cindex = GetCharacterIndex(aAt);
  if (cindex >= (int)line.size()) return true;

  if (mColorizerEnabled)
    return line[cindex].mColorIndex != line[size_t(cindex - 1)].mColorIndex;

  return isspace(line[cindex].mChar) != isspace(line[cindex - 1].mChar);
}

void TextEditor::RemoveLine(int aStart, int aEnd) {
  assert(!mReadOnly);
  assert(aEnd >= aStart);
  assert(mLines.size() > (size_t)(aEnd - aStart));

  ErrorMarkers etmp;
  for (auto& i : mErrorMarkers) {
    ErrorMarkers::value_type e(i.first >= aStart ? i.first - 1 : i.first,
                               i.second);
    if (e.first >= aStart && e.first <= aEnd) continue;
    etmp.insert(e);
  }
  mErrorMarkers = std::move(etmp);

  Breakpoints btmp;
  for (auto i : mBreakpoints) {
    if (i >= aStart && i <= aEnd) continue;
    btmp.insert(i >= aStart ? i - 1 : i);
  }
  mBreakpoints = std::move(btmp);

  mLines.erase(mLines.begin() + aStart, mLines.begin() + aEnd);
  assert(!mLines.empty());

  mTextChanged = true;
}

void TextEditor::RemoveLine(int aIndex) {
  assert(!mReadOnly);
  assert(mLines.size() > 1);

  ErrorMarkers etmp;
  for (auto& i : mErrorMarkers) {
    ErrorMarkers::value_type e(i.first > aIndex ? i.first - 1 : i.first,
                               i.second);
    if (e.first - 1 == aIndex) continue;
    etmp.insert(e);
  }
  mErrorMarkers = std::move(etmp);

  Breakpoints btmp;
  for (auto i : mBreakpoints) {
    if (i == aIndex) continue;
    btmp.insert(i >= aIndex ? i - 1 : i);
  }
  mBreakpoints = std::move(btmp);

  mLines.erase(mLines.begin() + aIndex);
  assert(!mLines.empty());

  mTextChanged = true;
}

TextEditor::Line& TextEditor::InsertLine(int aIndex) {
  assert(!mReadOnly);

  auto& result = *mLines.insert(mLines.begin() + aIndex, Line());

  ErrorMarkers etmp;
  for (auto& i : mErrorMarkers)
    etmp.insert(ErrorMarkers::value_type(
        i.first >= aIndex ? i.first + 1 : i.first, i.second));
  mErrorMarkers = std::move(etmp);

  Breakpoints btmp;
  for (auto i : mBreakpoints) btmp.insert(i >= aIndex ? i + 1 : i);
  mBreakpoints = std::move(btmp);

  return result;
}

std::string TextEditor::GetWordUnderCursor() const {
  auto c = GetCursorPosition();
  return GetWordAt(c);
}

std::string TextEditor::GetWordAt(const Coordinates& aCoords) const {
  auto start = FindWordStart(aCoords);
  auto end = FindWordEnd(aCoords);

  std::string r;

  auto istart = GetCharacterIndex(start);
  auto iend = GetCharacterIndex(end);

  for (auto it = istart; it < iend; ++it)
    r.push_back(mLines[aCoords.mLine][it].mChar);

  return r;
}

ImU32 TextEditor::GetGlyphColor(const Glyph& aGlyph) const {
  if (!mColorizerEnabled) return mPalette[(int)PaletteIndex::Default];
  if (aGlyph.mComment) return mPalette[(int)PaletteIndex::Comment];
  if (aGlyph.mMultiLineComment)
    return mPalette[(int)PaletteIndex::MultiLineComment];
  auto const color = mPalette[(int)aGlyph.mColorIndex];
  if (aGlyph.mPreprocessor) {
    const auto ppcolor = mPalette[(int)PaletteIndex::Preprocessor];
    const int c0 = ((ppcolor & 0xff) + (color & 0xff)) / 2;
    const int c1 = (((ppcolor >> 8) & 0xff) + ((color >> 8) & 0xff)) / 2;
    const int c2 = (((ppcolor >> 16) & 0xff) + ((color >> 16) & 0xff)) / 2;
    const int c3 = (((ppcolor >> 24) & 0xff) + ((color >> 24) & 0xff)) / 2;
    return ImU32(c0 | (c1 << 8) | (c2 << 16) | (c3 << 24));
  }
  return color;
}

void TextEditor::HandleKeyboardInputs() {
  ImGuiIO& io = ImGui::GetIO();
  auto shift = io.KeyShift;
  auto ctrl = io.ConfigMacOSXBehaviors ? io.KeySuper : io.KeyCtrl;
  auto alt = io.ConfigMacOSXBehaviors ? io.KeyCtrl : io.KeyAlt;

  if (ImGui::IsWindowFocused()) {
    if (ImGui::IsWindowHovered())
      ImGui::SetMouseCursor(ImGuiMouseCursor_TextInput);
    // ImGui::CaptureKeyboardFromApp(true);

    io.WantCaptureKeyboard = true;
    io.WantTextInput = true;

    if (!IsReadOnly() && ctrl && !shift && !alt &&
        ImGui::IsKeyPressed(ImGuiKey_Z))
      Undo();
    else if (!IsReadOnly() && !ctrl && !shift && alt &&
             ImGui::IsKeyPressed(ImGuiKey_Backspace))
      Undo();
    else if (!IsReadOnly() && ctrl && !shift && !alt &&
             ImGui::IsKeyPressed(ImGuiKey_Y))
      Redo();
    else if (!ctrl && !alt && ImGui::IsKeyPressed(ImGuiKey_UpArrow))
      MoveUp(1, shift);
    else if (!ctrl && !alt && ImGui::IsKeyPressed(ImGuiKey_DownArrow))
      MoveDown(1, shift);
    else if (!alt && ImGui::IsKeyPressed(ImGuiKey_LeftArrow))
      MoveLeft(1, shift, ctrl);
    else if (!alt && ImGui::IsKeyPressed(ImGuiKey_RightArrow))
      MoveRight(1, shift, ctrl);
    else if (!alt && ImGui::IsKeyPressed(ImGuiKey_PageUp))
      MoveUp(GetPageSize() - 4, shift);
    else if (!alt && ImGui::IsKeyPressed(ImGuiKey_PageDown))
      MoveDown(GetPageSize() - 4, shift);
    else if (!alt && ctrl && ImGui::IsKeyPressed(ImGuiKey_Home))
      MoveTop(shift);
    else if (ctrl && !alt && ImGui::IsKeyPressed(ImGuiKey_End))
      MoveBottom(shift);
    else if (!ctrl && !alt && ImGui::IsKeyPressed(ImGuiKey_Home))
      MoveHome(shift);
    else if (!ctrl && !alt && ImGui::IsKeyPressed(ImGuiKey_End))
      MoveEnd(shift);
    else if (!IsReadOnly() && !ctrl && !shift && !alt &&
             ImGui::IsKeyPressed(ImGuiKey_Delete))
      Delete();
    else if (!IsReadOnly() && !ctrl && !shift && !alt &&
             ImGui::IsKeyPressed(ImGuiKey_Backspace))
      Backspace();
    else if (!ctrl && !shift && !alt && ImGui::IsKeyPressed(ImGuiKey_Insert))
      mOverwrite ^= true;
    else if (ctrl && !shift && !alt && ImGui::IsKeyPressed(ImGuiKey_Insert))
      Copy();
    else if (ctrl && !shift && !alt && ImGui::IsKeyPressed(ImGuiKey_C))
      Copy();
    else if (!IsReadOnly() && !ctrl && shift && !alt &&
             ImGui::IsKeyPressed(ImGuiKey_Insert))
      Paste();
    else if (!IsReadOnly() && ctrl && !shift && !alt &&
             ImGui::IsKeyPressed(ImGuiKey_V))
      Paste();
    else if (ctrl && !shift && !alt && ImGui::IsKeyPressed(ImGuiKey_X))
      Cut();
    else if (!ctrl && shift && !alt && ImGui::IsKeyPressed(ImGuiKey_Delete))
      Cut();
    else if (ctrl && !shift && !alt && ImGui::IsKeyPressed(ImGuiKey_A))
      SelectAll();
    else if (!IsReadOnly() && !ctrl && !shift && !alt &&
             ImGui::IsKeyPressed(ImGuiKey_Enter))
      EnterCharacter('\n', false);
    else if (!IsReadOnly() && !ctrl && !alt &&
             ImGui::IsKeyPressed(ImGuiKey_Tab))
      EnterCharacter('\t', shift);

    if (!IsReadOnly() && !io.InputQueueCharacters.empty()) {
      for (int i = 0; i < io.InputQueueCharacters.Size; i++) {
        auto c = io.InputQueueCharacters[i];
        if (c != 0 && (c == '\n' || c >= 32)) EnterCharacter(c, shift);
      }
      io.InputQueueCharacters.resize(0);
    }
  }
}

void TextEditor::HandleMouseInputs() {
  ImGuiIO& io = ImGui::GetIO();
  auto shift = io.KeyShift;
  auto ctrl = io.ConfigMacOSXBehaviors ? io.KeySuper : io.KeyCtrl;
  auto alt = io.ConfigMacOSXBehaviors ? io.KeyCtrl : io.KeyAlt;

  if (ImGui::IsWindowHovered()) {
    if (!shift && !alt) {
      auto click = ImGui::IsMouseClicked(0);
      auto doubleClick = ImGui::IsMouseDoubleClicked(0);
      auto t = ImGui::GetTime();
      auto tripleClick =
          click && !doubleClick &&
          (mLastClick != -1.0f && (t - mLastClick) < io.MouseDoubleClickTime);

      /*
      Left mouse button triple click
      */

      if (tripleClick) {
        if (!ctrl) {
          mState.mCursorPosition = mInteractiveStart = mInteractiveEnd =
              ScreenPosToCoordinates(ImGui::GetMousePos());
          mSelectionMode = SelectionMode::Line;
          SetSelection(mInteractiveStart, mInteractiveEnd, mSelectionMode);
        }

        mLastClick = -1.0f;
      }

      /*
      Left mouse button double click
      */

      else if (doubleClick) {
        if (!ctrl) {
          mState.mCursorPosition = mInteractiveStart = mInteractiveEnd =
              ScreenPosToCoordinates(ImGui::GetMousePos());
          if (mSelectionMode == SelectionMode::Line)
            mSelectionMode = SelectionMode::Normal;
          else
            mSelectionMode = SelectionMode::Word;
          SetSelection(mInteractiveStart, mInteractiveEnd, mSelectionMode);
        }

        mLastClick = (float)ImGui::GetTime();
      }

      /*
      Left mouse button click
      */
      else if (click) {
        mState.mCursorPosition = mInteractiveStart = mInteractiveEnd =
            ScreenPosToCoordinates(ImGui::GetMousePos());
        if (ctrl)
          mSelectionMode = SelectionMode::Word;
        else
          mSelectionMode = SelectionMode::Normal;
        SetSelection(mInteractiveStart, mInteractiveEnd, mSelectionMode);

        mLastClick = (float)ImGui::GetTime();
      }
      // Mouse left button dragging (=> update selection)
      else if (ImGui::IsMouseDragging(0) && ImGui::IsMouseDown(0)) {
        io.WantCaptureMouse = true;
        mState.mCursorPosition = mInteractiveEnd =
            ScreenPosToCoordinates(ImGui::GetMousePos());
        SetSelection(mInteractiveStart, mInteractiveEnd, mSelectionMode);
      }
    }
  }
}

void TextEditor::Render() {
  /* Compute mCharAdvance regarding to scaled font size (Ctrl + mouse wheel)*/
  const float fontSize = ImGui::GetFont()
                             ->CalcTextSizeA(ImGui::GetFontSize(), FLT_MAX,
                                             -1.0f, "#", nullptr, nullptr)
                             .x;
  mCharAdvance =
      ImVec2(fontSize, ImGui::GetTextLineHeightWithSpacing() * mLineSpacing);

  /* Update palette with the current alpha from style */
  for (int i = 0; i < (int)PaletteIndex::Max; ++i) {
    auto color = ImGui::ColorConvertU32ToFloat4(mPaletteBase[i]);
    color.w *= ImGui::GetStyle().Alpha;
    mPalette[i] = ImGui::ColorConvertFloat4ToU32(color);
  }

  assert(mLineBuffer.empty());

  auto contentSize = ImGui::GetWindowContentRegionMax();
  auto drawList = ImGui::GetWindowDrawList();
  float longest(mTextStart);

  if (mScrollToTop) {
    mScrollToTop = false;
    ImGui::SetScrollY(0.f);
  }

  ImVec2 cursorScreenPos = ImGui::GetCursorScreenPos();
  auto scrollX = ImGui::GetScrollX();
  auto scrollY = ImGui::GetScrollY();

  auto lineNo = (int)floor(scrollY / mCharAdvance.y);
  auto globalLineMax = (int)mLines.size();
  auto lineMax = std::max(
      0, std::min(
             (int)mLines.size() - 1,
             lineNo + (int)floor((scrollY + contentSize.y) / mCharAdvance.y)));

  // Deduce mTextStart by evaluating mLines size (global lineMax) plus two
  // spaces as text width
  char buf[16];
  snprintf(buf, 16, " %d ", globalLineMax);
  mTextStart = ImGui::GetFont()
                   ->CalcTextSizeA(ImGui::GetFontSize(), FLT_MAX, -1.0f, buf,
                                   nullptr, nullptr)
                   .x +
               mLeftMargin;

  if (!mLines.empty()) {
    float spaceSize = ImGui::GetFont()
                          ->CalcTextSizeA(ImGui::GetFontSize(), FLT_MAX, -1.0f,
                                          " ", nullptr, nullptr)
                          .x;

    while (lineNo <= lineMax) {
      ImVec2 lineStartScreenPos = ImVec2(
          cursorScreenPos.x, cursorScreenPos.y + lineNo * mCharAdvance.y);
      ImVec2 textScreenPos =
          ImVec2(lineStartScreenPos.x + mTextStart, lineStartScreenPos.y);

      auto& line = mLines[lineNo];
      longest = std::max(mTextStart + TextDistanceToLineStart(Coordinates(
                                          lineNo, GetLineMaxColumn(lineNo))),
                         longest);
      auto columnNo = 0;
      Coordinates lineStartCoord(lineNo, 0);
      Coordinates lineEndCoord(lineNo, GetLineMaxColumn(lineNo));

      // Draw selection for the current line
      float sstart = -1.0f;
      float ssend = -1.0f;

      assert(mState.mSelectionStart <= mState.mSelectionEnd);
      if (mState.mSelectionStart <= lineEndCoord)
        sstart = mState.mSelectionStart > lineStartCoord
                     ? TextDistanceToLineStart(mState.mSelectionStart)
                     : 0.0f;
      if (mState.mSelectionEnd > lineStartCoord)
        ssend = TextDistanceToLineStart(mState.mSelectionEnd < lineEndCoord
                                            ? mState.mSelectionEnd
                                            : lineEndCoord);

      if (mState.mSelectionEnd.mLine > lineNo) ssend += mCharAdvance.x;

      if (sstart != -1 && ssend != -1 && sstart < ssend) {
        ImVec2 vstart(lineStartScreenPos.x + mTextStart + sstart,
                      lineStartScreenPos.y);
        ImVec2 vend(lineStartScreenPos.x + mTextStart + ssend,
                    lineStartScreenPos.y + mCharAdvance.y);
        drawList->AddRectFilled(vstart, vend,
                                mPalette[(int)PaletteIndex::Selection]);
      }

      // Draw breakpoints
      auto start = ImVec2(lineStartScreenPos.x + scrollX, lineStartScreenPos.y);

      if (mBreakpoints.count(lineNo + 1) != 0) {
        auto end = ImVec2(lineStartScreenPos.x + contentSize.x + 2.0f * scrollX,
                          lineStartScreenPos.y + mCharAdvance.y);
        drawList->AddRectFilled(start, end,
                                mPalette[(int)PaletteIndex::Breakpoint]);
      }

      // Draw error markers
      auto errorIt = mErrorMarkers.find(lineNo + 1);
      if (errorIt != mErrorMarkers.end()) {
        auto end = ImVec2(lineStartScreenPos.x + contentSize.x + 2.0f * scrollX,
                          lineStartScreenPos.y + mCharAdvance.y);
        drawList->AddRectFilled(start, end,
                                mPalette[(int)PaletteIndex::ErrorMarker]);

        if (ImGui::IsMouseHoveringRect(lineStartScreenPos, end)) {
          ImGui::BeginTooltip();
          ImGui::PushStyleColor(ImGuiCol_Text, ImVec4(1.0f, 0.2f, 0.2f, 1.0f));
          ImGui::Text("Error at line %d:", errorIt->first);
          ImGui::PopStyleColor();
          ImGui::Separator();
          ImGui::PushStyleColor(ImGuiCol_Text, ImVec4(1.0f, 1.0f, 0.2f, 1.0f));
          ImGui::Text("%s", errorIt->second.c_str());
          ImGui::PopStyleColor();
          ImGui::EndTooltip();
        }
      }

      // Draw line number (right aligned)
      snprintf(buf, 16, "%d  ", lineNo + 1);

      auto lineNoWidth = ImGui::GetFont()
                             ->CalcTextSizeA(ImGui::GetFontSize(), FLT_MAX,
                                             -1.0f, buf, nullptr, nullptr)
                             .x;
      drawList->AddText(ImVec2(lineStartScreenPos.x + mTextStart - lineNoWidth,
                               lineStartScreenPos.y),
                        mPalette[(int)PaletteIndex::LineNumber], buf);

      if (mState.mCursorPosition.mLine == lineNo) {
        auto focused = ImGui::IsWindowFocused();

        // Highlight the current line (where the cursor is)
        if (!HasSelection()) {
          auto end = ImVec2(start.x + contentSize.x + scrollX,
                            start.y + mCharAdvance.y);
          drawList->AddRectFilled(
              start, end,
              mPalette[(int)(focused ? PaletteIndex::CurrentLineFill
                                     : PaletteIndex::CurrentLineFillInactive)]);
          drawList->AddRect(start, end,
                            mPalette[(int)PaletteIndex::CurrentLineEdge], 1.0f);
        }

        // Render the cursor
        if (focused) {
          auto timeEnd =
              std::chrono::duration_cast<std::chrono::milliseconds>(
                  std::chrono::system_clock::now().time_since_epoch())
                  .count();
          auto elapsed = timeEnd - mStartTime;
          if (elapsed > 400) {
            float width = 1.0f;
            auto cindex = GetCharacterIndex(mState.mCursorPosition);
            float cx = TextDistanceToLineStart(mState.mCursorPosition);

            if (mOverwrite && cindex < (int)line.size()) {
              auto c = line[cindex].mChar;
              if (c == '\t') {
                auto x = (1.0f + std::floor((1.0f + cx) /
                                            (float(mTabSize) * spaceSize))) *
                         (float(mTabSize) * spaceSize);
                width = x - cx;
              } else {
                char buf2[2];
                buf2[0] = line[cindex].mChar;
                buf2[1] = '\0';
                width = ImGui::GetFont()
                            ->CalcTextSizeA(ImGui::GetFontSize(), FLT_MAX,
                                            -1.0f, buf2)
                            .x;
              }
            }
            ImVec2 cstart(textScreenPos.x + cx, lineStartScreenPos.y);
            ImVec2 cend(textScreenPos.x + cx + width,
                        lineStartScreenPos.y + mCharAdvance.y);
            drawList->AddRectFilled(cstart, cend,
                                    mPalette[(int)PaletteIndex::Cursor]);
            if (elapsed > 800) mStartTime = timeEnd;
          }
        }
      }

      // Render colorized text
      auto prevColor = line.empty() ? mPalette[(int)PaletteIndex::Default]
                                    : GetGlyphColor(line[0]);
      ImVec2 bufferOffset;

      for (int i = 0; i < line.size();) {
        auto& glyph = line[i];
        auto color = GetGlyphColor(glyph);

        if ((color != prevColor || glyph.mChar == '\t' || glyph.mChar == ' ') &&
            !mLineBuffer.empty()) {
          const ImVec2 newOffset(textScreenPos.x + bufferOffset.x,
                                 textScreenPos.y + bufferOffset.y);
          drawList->AddText(newOffset, prevColor, mLineBuffer.c_str());
          auto textSize = ImGui::GetFont()->CalcTextSizeA(
              ImGui::GetFontSize(), FLT_MAX, -1.0f, mLineBuffer.c_str(),
              nullptr, nullptr);
          bufferOffset.x += textSize.x;
          mLineBuffer.clear();
        }
        prevColor = color;

        if (glyph.mChar == '\t') {
          auto oldX = bufferOffset.x;
          bufferOffset.x = (1.0f + std::floor((1.0f + bufferOffset.x) /
                                              (float(mTabSize) * spaceSize))) *
                           (float(mTabSize) * spaceSize);
          ++i;

          if (mShowWhitespaces) {
            const auto s = ImGui::GetFontSize();
            const auto x1 = textScreenPos.x + oldX + 1.0f;
            const auto x2 = textScreenPos.x + bufferOffset.x - 1.0f;
            const auto y = textScreenPos.y + bufferOffset.y + s * 0.5f;
            const ImVec2 p1(x1, y);
            const ImVec2 p2(x2, y);
            const ImVec2 p3(x2 - s * 0.2f, y - s * 0.2f);
            const ImVec2 p4(x2 - s * 0.2f, y + s * 0.2f);
            drawList->AddLine(p1, p2, 0x90909090);
            drawList->AddLine(p2, p3, 0x90909090);
            drawList->AddLine(p2, p4, 0x90909090);
          }
        } else if (glyph.mChar == ' ') {
          if (mShowWhitespaces) {
            const auto s = ImGui::GetFontSize();
            const auto x = textScreenPos.x + bufferOffset.x + spaceSize * 0.5f;
            const auto y = textScreenPos.y + bufferOffset.y + s * 0.5f;
            drawList->AddCircleFilled(ImVec2(x, y), 1.5f, 0x80808080, 4);
          }
          bufferOffset.x += spaceSize;
          i++;
        } else {
          auto l = UTF8CharLength(glyph.mChar);
          while (l-- > 0) mLineBuffer.push_back(line[i++].mChar);
        }
        ++columnNo;
      }

      if (!mLineBuffer.empty()) {
        const ImVec2 newOffset(textScreenPos.x + bufferOffset.x,
                               textScreenPos.y + bufferOffset.y);
        drawList->AddText(newOffset, prevColor, mLineBuffer.c_str());
        mLineBuffer.clear();
      }

      ++lineNo;
    }

    // Draw a tooltip on known identifiers/preprocessor symbols
    if (ImGui::IsMousePosValid()) {
      auto id = GetWordAt(ScreenPosToCoordinates(ImGui::GetMousePos()));
      if (!id.empty()) {
        auto it = mLanguageDefinition.mIdentifiers.find(id);
        if (it != mLanguageDefinition.mIdentifiers.end()) {
          ImGui::BeginTooltip();
          ImGui::TextUnformatted(it->second.mDeclaration.c_str());
          ImGui::EndTooltip();
        } else {
          auto pi = mLanguageDefinition.mPreprocIdentifiers.find(id);
          if (pi != mLanguageDefinition.mPreprocIdentifiers.end()) {
            ImGui::BeginTooltip();
            ImGui::TextUnformatted(pi->second.mDeclaration.c_str());
            ImGui::EndTooltip();
          }
        }
      }
    }
  }

  ImGui::Dummy(ImVec2((longest + 2), mLines.size() * mCharAdvance.y));

  if (mScrollToCursor) {
    EnsureCursorVisible();
    ImGui::SetWindowFocus();
    mScrollToCursor = false;
  }
}

void TextEditor::Render(const char* aTitle, const ImVec2& aSize, bool aBorder) {
  mWithinRender = true;
  mTextChanged = false;
  mCursorPositionChanged = false;

  ImGui::PushStyleColor(
      ImGuiCol_ChildBg,
      ImGui::ColorConvertU32ToFloat4(mPalette[(int)PaletteIndex::Background]));
  ImGui::PushStyleVar(ImGuiStyleVar_ItemSpacing, ImVec2(0.0f, 0.0f));
  if (!mIgnoreImGuiChild)
    ImGui::BeginChild(aTitle, aSize, aBorder,
                      ImGuiWindowFlags_HorizontalScrollbar |
                          ImGuiWindowFlags_AlwaysHorizontalScrollbar |
                          ImGuiWindowFlags_NoMove);

  if (mHandleKeyboardInputs) {
    HandleKeyboardInputs();
    ImGui::PushAllowKeyboardFocus(true);
  }

  if (mHandleMouseInputs) HandleMouseInputs();

  ColorizeInternal();
  Render();

  if (mHandleKeyboardInputs) ImGui::PopAllowKeyboardFocus();

  if (!mIgnoreImGuiChild) ImGui::EndChild();

  ImGui::PopStyleVar();
  ImGui::PopStyleColor();

  mWithinRender = false;
}

void TextEditor::SetText(const std::string& aText) {
  mLines.clear();
  mLines.emplace_back(Line());
  for (auto chr : aText) {
    if (chr == '\r') {
      // ignore the carriage return character
    } else if (chr == '\n')
      mLines.emplace_back(Line());
    else {
      mLines.back().emplace_back(Glyph(chr, PaletteIndex::Default));
    }
  }

  mTextChanged = true;
  mScrollToTop = true;

  mUndoBuffer.clear();
  mUndoIndex = 0;

  Colorize();
}

void TextEditor::SetTextLines(const std::vector<std::string>& aLines) {
  mLines.clear();

  if (aLines.empty()) {
    mLines.emplace_back(Line());
  } else {
    mLines.resize(aLines.size());

    for (size_t i = 0; i < aLines.size(); ++i) {
      const std::string& aLine = aLines[i];

      mLines[i].reserve(aLine.size());
      for (size_t j = 0; j < aLine.size(); ++j)
        mLines[i].emplace_back(Glyph(aLine[j], PaletteIndex::Default));
    }
  }

  mTextChanged = true;
  mScrollToTop = true;

  mUndoBuffer.clear();
  mUndoIndex = 0;

  Colorize();
}

void TextEditor::EnterCharacter(ImWchar aChar, bool aShift) {
  assert(!mReadOnly);

  UndoRecord u;

  u.mBefore = mState;

  if (HasSelection()) {
    if (aChar == '\t' &&
        mState.mSelectionStart.mLine != mState.mSelectionEnd.mLine) {
      auto start = mState.mSelectionStart;
      auto end = mState.mSelectionEnd;
      auto originalEnd = end;

      if (start > end) std::swap(start, end);
      start.mColumn = 0;
      //			end.mColumn = end.mLine < mLines.size() ?
      //mLines[end.mLine].size() : 0;
      if (end.mColumn == 0 && end.mLine > 0) --end.mLine;
      if (end.mLine >= (int)mLines.size())
        end.mLine = mLines.empty() ? 0 : (int)mLines.size() - 1;
      end.mColumn = GetLineMaxColumn(end.mLine);

      // if (end.mColumn >= GetLineMaxColumn(end.mLine))
      //	end.mColumn = GetLineMaxColumn(end.mLine) - 1;

      u.mRemovedStart = start;
      u.mRemovedEnd = end;
      u.mRemoved = GetText(start, end);

      bool modified = false;

      for (int i = start.mLine; i <= end.mLine; i++) {
        auto& line = mLines[i];
        if (aShift) {
          if (!line.empty()) {
            if (line.front().mChar == '\t') {
              line.erase(line.begin());
              modified = true;
            } else {
              for (int j = 0;
                   j < mTabSize && !line.empty() && line.front().mChar == ' ';
                   j++) {
                line.erase(line.begin());
                modified = true;
              }
            }
          }
        } else {
          line.insert(line.begin(),
                      Glyph('\t', TextEditor::PaletteIndex::Background));
          modified = true;
        }
      }

      if (modified) {
        start = Coordinates(start.mLine, GetCharacterColumn(start.mLine, 0));
        Coordinates rangeEnd;
        if (originalEnd.mColumn != 0) {
          end = Coordinates(end.mLine, GetLineMaxColumn(end.mLine));
          rangeEnd = end;
          u.mAdded = GetText(start, end);
        } else {
          end = Coordinates(originalEnd.mLine, 0);
          rangeEnd =
              Coordinates(end.mLine - 1, GetLineMaxColumn(end.mLine - 1));
          u.mAdded = GetText(start, rangeEnd);
        }

        u.mAddedStart = start;
        u.mAddedEnd = rangeEnd;
        u.mAfter = mState;

        mState.mSelectionStart = start;
        mState.mSelectionEnd = end;
        AddUndo(u);

        mTextChanged = true;

        EnsureCursorVisible();
      }

      return;
    }  // c == '\t'
    else {
      u.mRemoved = GetSelectedText();
      u.mRemovedStart = mState.mSelectionStart;
      u.mRemovedEnd = mState.mSelectionEnd;
      DeleteSelection();
    }
  }  // HasSelection

  auto coord = GetActualCursorCoordinates();
  u.mAddedStart = coord;

  assert(!mLines.empty());

  if (aChar == '\n') {
    InsertLine(coord.mLine + 1);
    auto& line = mLines[coord.mLine];
    auto& newLine = mLines[coord.mLine + 1];

    if (mLanguageDefinition.mAutoIndentation)
      for (size_t it = 0; it < line.size() && isascii(line[it].mChar) &&
                          isblank(line[it].mChar);
           ++it)
        newLine.push_back(line[it]);

    const size_t whitespaceSize = newLine.size();
    auto cindex = GetCharacterIndex(coord);
    newLine.insert(newLine.end(), line.begin() + cindex, line.end());
    line.erase(line.begin() + cindex, line.begin() + line.size());
    SetCursorPosition(
        Coordinates(coord.mLine + 1,
                    GetCharacterColumn(coord.mLine + 1, (int)whitespaceSize)));
    u.mAdded = (char)aChar;
  } else {
    char buf[7];
    int e = ImTextCharToUtf8(buf, 7, aChar);
    if (e > 0) {
      buf[e] = '\0';
      auto& line = mLines[coord.mLine];
      auto cindex = GetCharacterIndex(coord);

      if (mOverwrite && cindex < (int)line.size()) {
        auto d = UTF8CharLength(line[cindex].mChar);

        u.mRemovedStart = mState.mCursorPosition;
        u.mRemovedEnd = Coordinates(
            coord.mLine, GetCharacterColumn(coord.mLine, cindex + d));

        while (d-- > 0 && cindex < (int)line.size()) {
          u.mRemoved += line[cindex].mChar;
          line.erase(line.begin() + cindex);
        }
      }

      for (auto p = buf; *p != '\0'; p++, ++cindex)
        line.insert(line.begin() + cindex, Glyph(*p, PaletteIndex::Default));
      u.mAdded = buf;

      SetCursorPosition(
          Coordinates(coord.mLine, GetCharacterColumn(coord.mLine, cindex)));
    } else
      return;
  }

  mTextChanged = true;

  u.mAddedEnd = GetActualCursorCoordinates();
  u.mAfter = mState;

  AddUndo(u);

  Colorize(coord.mLine - 1, 3);
  EnsureCursorVisible();
}

void TextEditor::SetReadOnly(bool aValue) { mReadOnly = aValue; }

void TextEditor::SetColorizerEnable(bool aValue) { mColorizerEnabled = aValue; }

void TextEditor::SetCursorPosition(const Coordinates& aPosition) {
  if (mState.mCursorPosition != aPosition) {
    mState.mCursorPosition = aPosition;
    mCursorPositionChanged = true;
    EnsureCursorVisible();
  }
}

void TextEditor::SetSelectionStart(const Coordinates& aPosition) {
  mState.mSelectionStart = SanitizeCoordinates(aPosition);
  if (mState.mSelectionStart > mState.mSelectionEnd)
    std::swap(mState.mSelectionStart, mState.mSelectionEnd);
}

void TextEditor::SetSelectionEnd(const Coordinates& aPosition) {
  mState.mSelectionEnd = SanitizeCoordinates(aPosition);
  if (mState.mSelectionStart > mState.mSelectionEnd)
    std::swap(mState.mSelectionStart, mState.mSelectionEnd);
}

void TextEditor::SetSelection(const Coordinates& aStart,
                              const Coordinates& aEnd, SelectionMode aMode) {
  auto oldSelStart = mState.mSelectionStart;
  auto oldSelEnd = mState.mSelectionEnd;

  mState.mSelectionStart = SanitizeCoordinates(aStart);
  mState.mSelectionEnd = SanitizeCoordinates(aEnd);
  if (mState.mSelectionStart > mState.mSelectionEnd)
    std::swap(mState.mSelectionStart, mState.mSelectionEnd);

  switch (aMode) {
    case TextEditor::SelectionMode::Normal:
      break;
    case TextEditor::SelectionMode::Word: {
      mState.mSelectionStart = FindWordStart(mState.mSelectionStart);
      if (!IsOnWordBoundary(mState.mSelectionEnd))
        mState.mSelectionEnd = FindWordEnd(FindWordStart(mState.mSelectionEnd));
      break;
    }
    case TextEditor::SelectionMode::Line: {
      const auto lineNo = mState.mSelectionEnd.mLine;
      const auto lineSize =
          (size_t)lineNo < mLines.size() ? mLines[lineNo].size() : 0;
      mState.mSelectionStart = Coordinates(mState.mSelectionStart.mLine, 0);
      mState.mSelectionEnd = Coordinates(lineNo, GetLineMaxColumn(lineNo));
      break;
    }
    default:
      break;
  }

  if (mState.mSelectionStart != oldSelStart ||
      mState.mSelectionEnd != oldSelEnd)
    mCursorPositionChanged = true;
}

void TextEditor::SetTabSize(int aValue) {
  mTabSize = std::max(0, std::min(32, aValue));
}

void TextEditor::InsertText(const std::string& aValue) {
  InsertText(aValue.c_str());
}

void TextEditor::InsertText(const char* aValue) {
  if (aValue == nullptr) return;

  auto pos = GetActualCursorCoordinates();
  auto start = std::min(pos, mState.mSelectionStart);
  int totalLines = pos.mLine - start.mLine;

  totalLines += InsertTextAt(pos, aValue);

  SetSelection(pos, pos);
  SetCursorPosition(pos);
  Colorize(start.mLine - 1, totalLines + 2);
}

void TextEditor::DeleteSelection() {
  assert(mState.mSelectionEnd >= mState.mSelectionStart);

  if (mState.mSelectionEnd == mState.mSelectionStart) return;

  DeleteRange(mState.mSelectionStart, mState.mSelectionEnd);

  SetSelection(mState.mSelectionStart, mState.mSelectionStart);
  SetCursorPosition(mState.mSelectionStart);
  Colorize(mState.mSelectionStart.mLine, 1);
}

void TextEditor::MoveUp(int aAmount, bool aSelect) {
  auto oldPos = mState.mCursorPosition;
  mState.mCursorPosition.mLine =
      std::max(0, mState.mCursorPosition.mLine - aAmount);
  if (oldPos != mState.mCursorPosition) {
    if (aSelect) {
      if (oldPos == mInteractiveStart)
        mInteractiveStart = mState.mCursorPosition;
      else if (oldPos == mInteractiveEnd)
        mInteractiveEnd = mState.mCursorPosition;
      else {
        mInteractiveStart = mState.mCursorPosition;
        mInteractiveEnd = oldPos;
      }
    } else
      mInteractiveStart = mInteractiveEnd = mState.mCursorPosition;
    SetSelection(mInteractiveStart, mInteractiveEnd);

    EnsureCursorVisible();
  }
}

void TextEditor::MoveDown(int aAmount, bool aSelect) {
  assert(mState.mCursorPosition.mColumn >= 0);
  auto oldPos = mState.mCursorPosition;
  mState.mCursorPosition.mLine = std::max(
      0,
      std::min((int)mLines.size() - 1, mState.mCursorPosition.mLine + aAmount));

  if (mState.mCursorPosition != oldPos) {
    if (aSelect) {
      if (oldPos == mInteractiveEnd)
        mInteractiveEnd = mState.mCursorPosition;
      else if (oldPos == mInteractiveStart)
        mInteractiveStart = mState.mCursorPosition;
      else {
        mInteractiveStart = oldPos;
        mInteractiveEnd = mState.mCursorPosition;
      }
    } else
      mInteractiveStart = mInteractiveEnd = mState.mCursorPosition;
    SetSelection(mInteractiveStart, mInteractiveEnd);

    EnsureCursorVisible();
  }
}

static bool IsUTFSequence(char c) { return (c & 0xC0) == 0x80; }

void TextEditor::MoveLeft(int aAmount, bool aSelect, bool aWordMode) {
  if (mLines.empty()) return;

  auto oldPos = mState.mCursorPosition;
  mState.mCursorPosition = GetActualCursorCoordinates();
  auto line = mState.mCursorPosition.mLine;
  auto cindex = GetCharacterIndex(mState.mCursorPosition);

  while (aAmount-- > 0) {
    if (cindex == 0) {
      if (line > 0) {
        --line;
        if ((int)mLines.size() > line)
          cindex = (int)mLines[line].size();
        else
          cindex = 0;
      }
    } else {
      --cindex;
      if (cindex > 0) {
        if ((int)mLines.size() > line) {
          while (cindex > 0 && IsUTFSequence(mLines[line][cindex].mChar))
            --cindex;
        }
      }
    }

    mState.mCursorPosition =
        Coordinates(line, GetCharacterColumn(line, cindex));
    if (aWordMode) {
      mState.mCursorPosition = FindWordStart(mState.mCursorPosition);
      cindex = GetCharacterIndex(mState.mCursorPosition);
    }
  }

  mState.mCursorPosition = Coordinates(line, GetCharacterColumn(line, cindex));

  assert(mState.mCursorPosition.mColumn >= 0);
  if (aSelect) {
    if (oldPos == mInteractiveStart)
      mInteractiveStart = mState.mCursorPosition;
    else if (oldPos == mInteractiveEnd)
      mInteractiveEnd = mState.mCursorPosition;
    else {
      mInteractiveStart = mState.mCursorPosition;
      mInteractiveEnd = oldPos;
    }
  } else
    mInteractiveStart = mInteractiveEnd = mState.mCursorPosition;
  SetSelection(
      mInteractiveStart, mInteractiveEnd,
      aSelect && aWordMode ? SelectionMode::Word : SelectionMode::Normal);

  EnsureCursorVisible();
}

void TextEditor::MoveRight(int aAmount, bool aSelect, bool aWordMode) {
  auto oldPos = mState.mCursorPosition;

  if (mLines.empty() || oldPos.mLine >= mLines.size()) return;

  auto cindex = GetCharacterIndex(mState.mCursorPosition);
  while (aAmount-- > 0) {
    auto lindex = mState.mCursorPosition.mLine;
    auto& line = mLines[lindex];

    if (cindex >= line.size()) {
      if (mState.mCursorPosition.mLine < mLines.size() - 1) {
        mState.mCursorPosition.mLine = std::max(
            0,
            std::min((int)mLines.size() - 1, mState.mCursorPosition.mLine + 1));
        mState.mCursorPosition.mColumn = 0;
      } else
        return;
    } else {
      cindex += UTF8CharLength(line[cindex].mChar);
      mState.mCursorPosition =
          Coordinates(lindex, GetCharacterColumn(lindex, cindex));
      if (aWordMode)
        mState.mCursorPosition = FindNextWord(mState.mCursorPosition);
    }
  }

  if (aSelect) {
    if (oldPos == mInteractiveEnd)
      mInteractiveEnd = SanitizeCoordinates(mState.mCursorPosition);
    else if (oldPos == mInteractiveStart)
      mInteractiveStart = mState.mCursorPosition;
    else {
      mInteractiveStart = oldPos;
      mInteractiveEnd = mState.mCursorPosition;
    }
  } else
    mInteractiveStart = mInteractiveEnd = mState.mCursorPosition;
  SetSelection(
      mInteractiveStart, mInteractiveEnd,
      aSelect && aWordMode ? SelectionMode::Word : SelectionMode::Normal);

  EnsureCursorVisible();
}

void TextEditor::MoveTop(bool aSelect) {
  auto oldPos = mState.mCursorPosition;
  SetCursorPosition(Coordinates(0, 0));

  if (mState.mCursorPosition != oldPos) {
    if (aSelect) {
      mInteractiveEnd = oldPos;
      mInteractiveStart = mState.mCursorPosition;
    } else
      mInteractiveStart = mInteractiveEnd = mState.mCursorPosition;
    SetSelection(mInteractiveStart, mInteractiveEnd);
  }
}

void TextEditor::TextEditor::MoveBottom(bool aSelect) {
  auto oldPos = GetCursorPosition();
  auto newPos = Coordinates((int)mLines.size() - 1, 0);
  SetCursorPosition(newPos);
  if (aSelect) {
    mInteractiveStart = oldPos;
    mInteractiveEnd = newPos;
  } else
    mInteractiveStart = mInteractiveEnd = newPos;
  SetSelection(mInteractiveStart, mInteractiveEnd);
}

void TextEditor::MoveHome(bool aSelect) {
  auto oldPos = mState.mCursorPosition;
  SetCursorPosition(Coordinates(mState.mCursorPosition.mLine, 0));

  if (mState.mCursorPosition != oldPos) {
    if (aSelect) {
      if (oldPos == mInteractiveStart)
        mInteractiveStart = mState.mCursorPosition;
      else if (oldPos == mInteractiveEnd)
        mInteractiveEnd = mState.mCursorPosition;
      else {
        mInteractiveStart = mState.mCursorPosition;
        mInteractiveEnd = oldPos;
      }
    } else
      mInteractiveStart = mInteractiveEnd = mState.mCursorPosition;
    SetSelection(mInteractiveStart, mInteractiveEnd);
  }
}

void TextEditor::MoveEnd(bool aSelect) {
  auto oldPos = mState.mCursorPosition;
  SetCursorPosition(Coordinates(mState.mCursorPosition.mLine,
                                GetLineMaxColumn(oldPos.mLine)));

  if (mState.mCursorPosition != oldPos) {
    if (aSelect) {
      if (oldPos == mInteractiveEnd)
        mInteractiveEnd = mState.mCursorPosition;
      else if (oldPos == mInteractiveStart)
        mInteractiveStart = mState.mCursorPosition;
      else {
        mInteractiveStart = oldPos;
        mInteractiveEnd = mState.mCursorPosition;
      }
    } else
      mInteractiveStart = mInteractiveEnd = mState.mCursorPosition;
    SetSelection(mInteractiveStart, mInteractiveEnd);
  }
}

void TextEditor::Delete() {
  assert(!mReadOnly);

  if (mLines.empty()) return;

  UndoRecord u;
  u.mBefore = mState;

  if (HasSelection()) {
    u.mRemoved = GetSelectedText();
    u.mRemovedStart = mState.mSelectionStart;
    u.mRemovedEnd = mState.mSelectionEnd;

    DeleteSelection();
  } else {
    auto pos = GetActualCursorCoordinates();
    SetCursorPosition(pos);
    auto& line = mLines[pos.mLine];

    if (pos.mColumn == GetLineMaxColumn(pos.mLine)) {
      if (pos.mLine == (int)mLines.size() - 1) return;

      u.mRemoved = '\n';
      u.mRemovedStart = u.mRemovedEnd = GetActualCursorCoordinates();
      Advance(u.mRemovedEnd);

      auto& nextLine = mLines[pos.mLine + 1];
      line.insert(line.end(), nextLine.begin(), nextLine.end());
      RemoveLine(pos.mLine + 1);
    } else {
      auto cindex = GetCharacterIndex(pos);
      u.mRemovedStart = u.mRemovedEnd = GetActualCursorCoordinates();
      u.mRemovedEnd.mColumn++;
      u.mRemoved = GetText(u.mRemovedStart, u.mRemovedEnd);

      auto d = UTF8CharLength(line[cindex].mChar);
      while (d-- > 0 && cindex < (int)line.size())
        line.erase(line.begin() + cindex);
    }

    mTextChanged = true;

    Colorize(pos.mLine, 1);
  }

  u.mAfter = mState;
  AddUndo(u);
}

void TextEditor::Backspace() {
  assert(!mReadOnly);

  if (mLines.empty()) return;

  UndoRecord u;
  u.mBefore = mState;

  if (HasSelection()) {
    u.mRemoved = GetSelectedText();
    u.mRemovedStart = mState.mSelectionStart;
    u.mRemovedEnd = mState.mSelectionEnd;

    DeleteSelection();
  } else {
    auto pos = GetActualCursorCoordinates();
    SetCursorPosition(pos);

    if (mState.mCursorPosition.mColumn == 0) {
      if (mState.mCursorPosition.mLine == 0) return;

      u.mRemoved = '\n';
      u.mRemovedStart = u.mRemovedEnd =
          Coordinates(pos.mLine - 1, GetLineMaxColumn(pos.mLine - 1));
      Advance(u.mRemovedEnd);

      auto& line = mLines[mState.mCursorPosition.mLine];
      auto& prevLine = mLines[mState.mCursorPosition.mLine - 1];
      auto prevSize = GetLineMaxColumn(mState.mCursorPosition.mLine - 1);
      prevLine.insert(prevLine.end(), line.begin(), line.end());

      ErrorMarkers etmp;
      for (auto& i : mErrorMarkers)
        etmp.insert(ErrorMarkers::value_type(
            i.first - 1 == mState.mCursorPosition.mLine ? i.first - 1 : i.first,
            i.second));
      mErrorMarkers = std::move(etmp);

      RemoveLine(mState.mCursorPosition.mLine);
      --mState.mCursorPosition.mLine;
      mState.mCursorPosition.mColumn = prevSize;
    } else {
      auto& line = mLines[mState.mCursorPosition.mLine];
      auto cindex = GetCharacterIndex(pos) - 1;
      auto cend = cindex + 1;
      while (cindex > 0 && IsUTFSequence(line[cindex].mChar)) --cindex;

      // if (cindex > 0 && UTF8CharLength(line[cindex].mChar) > 1)
      //	--cindex;

      u.mRemovedStart = u.mRemovedEnd = GetActualCursorCoordinates();
      --u.mRemovedStart.mColumn;
      --mState.mCursorPosition.mColumn;

      while (cindex < line.size() && cend-- > cindex) {
        u.mRemoved += line[cindex].mChar;
        line.erase(line.begin() + cindex);
      }
    }

    mTextChanged = true;

    EnsureCursorVisible();
    Colorize(mState.mCursorPosition.mLine, 1);
  }

  u.mAfter = mState;
  AddUndo(u);
}

void TextEditor::SelectWordUnderCursor() {
  auto c = GetCursorPosition();
  SetSelection(FindWordStart(c), FindWordEnd(c));
}

void TextEditor::SelectAll() {
  SetSelection(Coordinates(0, 0), Coordinates((int)mLines.size(), 0));
}

bool TextEditor::HasSelection() const {
  return mState.mSelectionEnd > mState.mSelectionStart;
}

void TextEditor::Copy() {
  if (HasSelection()) {
    ImGui::SetClipboardText(GetSelectedText().c_str());
  } else {
    if (!mLines.empty()) {
      std::string str;
      auto& line = mLines[GetActualCursorCoordinates().mLine];
      for (auto& g : line) str.push_back(g.mChar);
      ImGui::SetClipboardText(str.c_str());
    }
  }
}

void TextEditor::Cut() {
  if (IsReadOnly()) {
    Copy();
  } else {
    if (HasSelection()) {
      UndoRecord u;
      u.mBefore = mState;
      u.mRemoved = GetSelectedText();
      u.mRemovedStart = mState.mSelectionStart;
      u.mRemovedEnd = mState.mSelectionEnd;

      Copy();
      DeleteSelection();

      u.mAfter = mState;
      AddUndo(u);
    }
  }
}

void TextEditor::Paste() {
  if (IsReadOnly()) return;

  auto clipText = ImGui::GetClipboardText();
  if (clipText != nullptr && strlen(clipText) > 0) {
    UndoRecord u;
    u.mBefore = mState;

    if (HasSelection()) {
      u.mRemoved = GetSelectedText();
      u.mRemovedStart = mState.mSelectionStart;
      u.mRemovedEnd = mState.mSelectionEnd;
      DeleteSelection();
    }

    u.mAdded = clipText;
    u.mAddedStart = GetActualCursorCoordinates();

    InsertText(clipText);

    u.mAddedEnd = GetActualCursorCoordinates();
    u.mAfter = mState;
    AddUndo(u);
  }
}

bool TextEditor::CanUndo() const { return !mReadOnly && mUndoIndex > 0; }

bool TextEditor::CanRedo() const {
  return !mReadOnly && mUndoIndex < (int)mUndoBuffer.size();
}

void TextEditor::Undo(int aSteps) {
  while (CanUndo() && aSteps-- > 0) mUndoBuffer[--mUndoIndex].Undo(this);
}

void TextEditor::Redo(int aSteps) {
  while (CanRedo() && aSteps-- > 0) mUndoBuffer[mUndoIndex++].Redo(this);
}

const TextEditor::Palette& TextEditor::GetDarkPalette() {
  const static Palette p = {{
      0xff7f7f7f,  // Default
      0xffd69c56,  // Keyword
      0xff00ff00,  // Number
      0xff7070e0,  // String
      0xff70a0e0,  // Char literal
      0xffffffff,  // Punctuation
      0xff408080,  // Preprocessor
      0xffaaaaaa,  // Identifier
      0xff9bc64d,  // Known identifier
      0xffc040a0,  // Preproc identifier
      0xff206020,  // Comment (single line)
      0xff406020,  // Comment (multi line)
      0xff101010,  // Background
      0xffe0e0e0,  // Cursor
      0x80a06020,  // Selection
      0x800020ff,  // ErrorMarker
      0x40f08000,  // Breakpoint
      0xff707000,  // Line number
      0x40000000,  // Current line fill
      0x40808080,  // Current line fill (inactive)
      0x40a0a0a0,  // Current line edge
  }};
  return p;
}

const TextEditor::Palette& TextEditor::GetLightPalette() {
  const static Palette p = {{
      0xff7f7f7f,  // None
      0xffff0c06,  // Keyword
      0xff008000,  // Number
      0xff2020a0,  // String
      0xff304070,  // Char literal
      0xff000000,  // Punctuation
      0xff406060,  // Preprocessor
      0xff404040,  // Identifier
      0xff606010,  // Known identifier
      0xffc040a0,  // Preproc identifier
      0xff205020,  // Comment (single line)
      0xff405020,  // Comment (multi line)
      0xffffffff,  // Background
      0xff000000,  // Cursor
      0x80600000,  // Selection
      0xa00010ff,  // ErrorMarker
      0x80f08000,  // Breakpoint
      0xff505000,  // Line number
      0x40000000,  // Current line fill
      0x40808080,  // Current line fill (inactive)
      0x40000000,  // Current line edge
  }};
  return p;
}

const TextEditor::Palette& TextEditor::GetRetroBluePalette() {
  const static Palette p = {{
      0xff00ffff,  // None
      0xffffff00,  // Keyword
      0xff00ff00,  // Number
      0xff808000,  // String
      0xff808000,  // Char literal
      0xffffffff,  // Punctuation
      0xff008000,  // Preprocessor
      0xff00ffff,  // Identifier
      0xffffffff,  // Known identifier
      0xffff00ff,  // Preproc identifier
      0xff808080,  // Comment (single line)
      0xff404040,  // Comment (multi line)
      0xff800000,  // Background
      0xff0080ff,  // Cursor
      0x80ffff00,  // Selection
      0xa00000ff,  // ErrorMarker
      0x80ff8000,  // Breakpoint
      0xff808000,  // Line number
      0x40000000,  // Current line fill
      0x40808080,  // Current line fill (inactive)
      0x40000000,  // Current line edge
  }};
  return p;
}

std::string TextEditor::GetText() const {
  return GetText(Coordinates(), Coordinates((int)mLines.size(), 0));
}

std::vector<std::string> TextEditor::GetTextLines() const {
  std::vector<std::string> result;

  result.reserve(mLines.size());

  for (auto& line : mLines) {
    std::string text;

    text.resize(line.size());

    for (size_t i = 0; i < line.size(); ++i) text[i] = line[i].mChar;

    result.emplace_back(std::move(text));
  }

  return result;
}

std::string TextEditor::GetSelectedText() const {
  return GetText(mState.mSelectionStart, mState.mSelectionEnd);
}

std::string TextEditor::GetCurrentLineText() const {
  auto lineLength = GetLineMaxColumn(mState.mCursorPosition.mLine);
  return GetText(Coordinates(mState.mCursorPosition.mLine, 0),
                 Coordinates(mState.mCursorPosition.mLine, lineLength));
}

void TextEditor::ProcessInputs() {}

void TextEditor::Colorize(int aFromLine, int aLines) {
  int toLine = aLines == -1 ? (int)mLines.size()
                            : std::min((int)mLines.size(), aFromLine + aLines);
  mColorRangeMin = std::min(mColorRangeMin, aFromLine);
  mColorRangeMax = std::max(mColorRangeMax, toLine);
  mColorRangeMin = std::max(0, mColorRangeMin);
  mColorRangeMax = std::max(mColorRangeMin, mColorRangeMax);
  mCheckComments = true;
}

void TextEditor::ColorizeRange(int aFromLine, int aToLine) {
  if (mLines.empty() || aFromLine >= aToLine) return;

  std::string buffer;
  std::cmatch results;
  std::string id;

  int endLine = std::max(0, std::min((int)mLines.size(), aToLine));
  for (int i = aFromLine; i < endLine; ++i) {
    auto& line = mLines[i];

    if (line.empty()) continue;

    buffer.resize(line.size());
    for (size_t j = 0; j < line.size(); ++j) {
      auto& col = line[j];
      buffer[j] = col.mChar;
      col.mColorIndex = PaletteIndex::Default;
    }

    const char* bufferBegin = &buffer.front();
    const char* bufferEnd = bufferBegin + buffer.size();

    auto last = bufferEnd;

    for (auto first = bufferBegin; first != last;) {
      const char* token_begin = nullptr;
      const char* token_end = nullptr;
      PaletteIndex token_color = PaletteIndex::Default;

      bool hasTokenizeResult = false;

      if (mLanguageDefinition.mTokenize != nullptr) {
        if (mLanguageDefinition.mTokenize(first, last, token_begin, token_end,
                                          token_color))
          hasTokenizeResult = true;
      }

      if (hasTokenizeResult == false) {
        // todo : remove
        // printf("using regex for %.*s\n", first + 10 < last ? 10 : int(last -
        // first), first);

        for (auto& p : mRegexList) {
          if (std::regex_search(first, last, results, p.first,
                                std::regex_constants::match_continuous)) {
            hasTokenizeResult = true;

            auto& v = *results.begin();
            token_begin = v.first;
            token_end = v.second;
            token_color = p.second;
            break;
          }
        }
      }

      if (hasTokenizeResult == false) {
        first++;
      } else {
        const size_t token_length = token_end - token_begin;

        if (token_color == PaletteIndex::Identifier) {
          id.assign(token_begin, token_end);

          // todo : allmost all language definitions use lower case to specify
          // keywords, so shouldn't this use ::tolower ?
          if (!mLanguageDefinition.mCaseSensitive)
            std::transform(id.begin(), id.end(), id.begin(), ::toupper);

          if (!line[first - bufferBegin].mPreprocessor) {
            if (mLanguageDefinition.mKeywords.count(id) != 0)
              token_color = PaletteIndex::Keyword;
            else if (mLanguageDefinition.mIdentifiers.count(id) != 0)
              token_color = PaletteIndex::KnownIdentifier;
            else if (mLanguageDefinition.mPreprocIdentifiers.count(id) != 0)
              token_color = PaletteIndex::PreprocIdentifier;
          } else {
            if (mLanguageDefinition.mPreprocIdentifiers.count(id) != 0)
              token_color = PaletteIndex::PreprocIdentifier;
          }
        }

        for (size_t j = 0; j < token_length; ++j)
          line[(token_begin - bufferBegin) + j].mColorIndex = token_color;

        first = token_end;
      }
    }
  }
}

void TextEditor::ColorizeInternal() {
  if (mLines.empty() || !mColorizerEnabled) return;

  if (mCheckComments) {
    auto endLine = mLines.size();
    auto endIndex = 0;
    auto commentStartLine = endLine;
    auto commentStartIndex = endIndex;
    auto withinString = false;
    auto withinSingleLineComment = false;
    auto withinPreproc = false;
    auto firstChar =
        true;  // there is no other non-whitespace characters in the line before
    auto concatenate = false;  // '\' on the very end of the line
    auto currentLine = 0;
    auto currentIndex = 0;
    while (currentLine < endLine || currentIndex < endIndex) {
      auto& line = mLines[currentLine];

      if (currentIndex == 0 && !concatenate) {
        withinSingleLineComment = false;
        withinPreproc = false;
        firstChar = true;
      }

      concatenate = false;

      if (!line.empty()) {
        auto& g = line[currentIndex];
        auto c = g.mChar;

        if (c != mLanguageDefinition.mPreprocChar && !isspace(c))
          firstChar = false;

        if (currentIndex == (int)line.size() - 1 &&
            line[line.size() - 1].mChar == '\\')
          concatenate = true;

        bool inComment = (commentStartLine < currentLine ||
                          (commentStartLine == currentLine &&
                           commentStartIndex <= currentIndex));

        if (withinString) {
          line[currentIndex].mMultiLineComment = inComment;

          if (c == '\"') {
            if (currentIndex + 1 < (int)line.size() &&
                line[currentIndex + 1].mChar == '\"') {
              currentIndex += 1;
              if (currentIndex < (int)line.size())
                line[currentIndex].mMultiLineComment = inComment;
            } else
              withinString = false;
          } else if (c == '\\') {
            currentIndex += 1;
            if (currentIndex < (int)line.size())
              line[currentIndex].mMultiLineComment = inComment;
          }
        } else {
          if (firstChar && c == mLanguageDefinition.mPreprocChar)
            withinPreproc = true;

          if (c == '\"') {
            withinString = true;
            line[currentIndex].mMultiLineComment = inComment;
          } else {
            auto pred = [](const char& a, const Glyph& b) {
              return a == b.mChar;
            };
            auto from = line.begin() + currentIndex;
            auto& startStr = mLanguageDefinition.mCommentStart;
            auto& singleStartStr = mLanguageDefinition.mSingleLineComment;

            if (singleStartStr.size() > 0 &&
                currentIndex + singleStartStr.size() <= line.size() &&
                equals(singleStartStr.begin(), singleStartStr.end(), from,
                       from + singleStartStr.size(), pred)) {
              withinSingleLineComment = true;
            } else if (!withinSingleLineComment &&
                       currentIndex + startStr.size() <= line.size() &&
                       equals(startStr.begin(), startStr.end(), from,
                              from + startStr.size(), pred)) {
              commentStartLine = currentLine;
              commentStartIndex = currentIndex;
            }

            inComment = inComment = (commentStartLine < currentLine ||
                                     (commentStartLine == currentLine &&
                                      commentStartIndex <= currentIndex));

            line[currentIndex].mMultiLineComment = inComment;
            line[currentIndex].mComment = withinSingleLineComment;

            auto& endStr = mLanguageDefinition.mCommentEnd;
            if (currentIndex + 1 >= (int)endStr.size() &&
                equals(endStr.begin(), endStr.end(), from + 1 - endStr.size(),
                       from + 1, pred)) {
              commentStartIndex = endIndex;
              commentStartLine = endLine;
            }
          }
        }
        line[currentIndex].mPreprocessor = withinPreproc;
        currentIndex += UTF8CharLength(c);
        if (currentIndex >= (int)line.size()) {
          currentIndex = 0;
          ++currentLine;
        }
      } else {
        currentIndex = 0;
        ++currentLine;
      }
    }
    mCheckComments = false;
  }

  if (mColorRangeMin < mColorRangeMax) {
    const int increment =
        (mLanguageDefinition.mTokenize == nullptr) ? 10 : 10000;
    const int to = std::min(mColorRangeMin + increment, mColorRangeMax);
    ColorizeRange(mColorRangeMin, to);
    mColorRangeMin = to;

    if (mColorRangeMax == mColorRangeMin) {
      mColorRangeMin = std::numeric_limits<int>::max();
      mColorRangeMax = 0;
    }
    return;
  }
}

float TextEditor::TextDistanceToLineStart(const Coordinates& aFrom) const {
  auto& line = mLines[aFrom.mLine];
  float distance = 0.0f;
  float spaceSize = ImGui::GetFont()
                        ->CalcTextSizeA(ImGui::GetFontSize(), FLT_MAX, -1.0f,
                                        " ", nullptr, nullptr)
                        .x;
  int colIndex = GetCharacterIndex(aFrom);
  for (size_t it = 0u; it < line.size() && it < colIndex;) {
    if (line[it].mChar == '\t') {
      distance = (1.0f + std::floor((1.0f + distance) /
                                    (float(mTabSize) * spaceSize))) *
                 (float(mTabSize) * spaceSize);
      ++it;
    } else {
      auto d = UTF8CharLength(line[it].mChar);
      char tempCString[7];
      int i = 0;
      for (; i < 6 && d-- > 0 && it < (int)line.size(); i++, it++)
        tempCString[i] = line[it].mChar;

      tempCString[i] = '\0';
      distance += ImGui::GetFont()
                      ->CalcTextSizeA(ImGui::GetFontSize(), FLT_MAX, -1.0f,
                                      tempCString, nullptr, nullptr)
                      .x;
    }
  }

  return distance;
}

void TextEditor::EnsureCursorVisible() {
  if (!mWithinRender) {
    mScrollToCursor = true;
    return;
  }

  float scrollX = ImGui::GetScrollX();
  float scrollY = ImGui::GetScrollY();

  auto height = ImGui::GetWindowHeight();
  auto width = ImGui::GetWindowWidth();

  auto top = 1 + (int)ceil(scrollY / mCharAdvance.y);
  auto bottom = (int)ceil((scrollY + height) / mCharAdvance.y);

  auto left = (int)ceil(scrollX / mCharAdvance.x);
  auto right = (int)ceil((scrollX + width) / mCharAdvance.x);

  auto pos = GetActualCursorCoordinates();
  auto len = TextDistanceToLineStart(pos);

  if (pos.mLine < top)
    ImGui::SetScrollY(std::max(0.0f, (pos.mLine - 1) * mCharAdvance.y));
  if (pos.mLine > bottom - 4)
    ImGui::SetScrollY(
        std::max(0.0f, (pos.mLine + 4) * mCharAdvance.y - height));
  if (len + mTextStart < left + 4)
    ImGui::SetScrollX(std::max(0.0f, len + mTextStart - 4));
  if (len + mTextStart > right - 4)
    ImGui::SetScrollX(std::max(0.0f, len + mTextStart + 4 - width));
}

int TextEditor::GetPageSize() const {
  auto height = ImGui::GetWindowHeight() - 20.0f;
  return (int)floor(height / mCharAdvance.y);
}

TextEditor::UndoRecord::UndoRecord(const std::string& aAdded,
                                   const TextEditor::Coordinates aAddedStart,
                                   const TextEditor::Coordinates aAddedEnd,
                                   const std::string& aRemoved,
                                   const TextEditor::Coordinates aRemovedStart,
                                   const TextEditor::Coordinates aRemovedEnd,
                                   TextEditor::EditorState& aBefore,
                                   TextEditor::EditorState& aAfter)
    : mAdded(aAdded),
      mAddedStart(aAddedStart),
      mAddedEnd(aAddedEnd),
      mRemoved(aRemoved),
      mRemovedStart(aRemovedStart),
      mRemovedEnd(aRemovedEnd),
      mBefore(aBefore),
      mAfter(aAfter) {
  assert(mAddedStart <= mAddedEnd);
  assert(mRemovedStart <= mRemovedEnd);
}

void TextEditor::UndoRecord::Undo(TextEditor* aEditor) {
  if (!mAdded.empty()) {
    aEditor->DeleteRange(mAddedStart, mAddedEnd);
    aEditor->Colorize(mAddedStart.mLine - 1,
                      mAddedEnd.mLine - mAddedStart.mLine + 2);
  }

  if (!mRemoved.empty()) {
    auto start = mRemovedStart;
    aEditor->InsertTextAt(start, mRemoved.c_str());
    aEditor->Colorize(mRemovedStart.mLine - 1,
                      mRemovedEnd.mLine - mRemovedStart.mLine + 2);
  }

  aEditor->mState = mBefore;
  aEditor->EnsureCursorVisible();
}

void TextEditor::UndoRecord::Redo(TextEditor* aEditor) {
  if (!mRemoved.empty()) {
    aEditor->DeleteRange(mRemovedStart, mRemovedEnd);
    aEditor->Colorize(mRemovedStart.mLine - 1,
                      mRemovedEnd.mLine - mRemovedStart.mLine + 1);
  }

  if (!mAdded.empty()) {
    auto start = mAddedStart;
    aEditor->InsertTextAt(start, mAdded.c_str());
    aEditor->Colorize(mAddedStart.mLine - 1,
                      mAddedEnd.mLine - mAddedStart.mLine + 1);
  }

  aEditor->mState = mAfter;
  aEditor->EnsureCursorVisible();
}

static bool TokenizeCStyleString(const char* in_begin, const char* in_end,
                                 const char*& out_begin, const char*& out_end) {
  const char* p = in_begin;

  if (*p == '"') {
    p++;

    while (p < in_end) {
      // handle end of string
      if (*p == '"') {
        out_begin = in_begin;
        out_end = p + 1;
        return true;
      }

      // handle escape character for "
      if (*p == '\\' && p + 1 < in_end && p[1] == '"') p++;

      p++;
    }
  }

  return false;
}

static bool TokenizeCStyleCharacterLiteral(const char* in_begin,
                                           const char* in_end,
                                           const char*& out_begin,
                                           const char*& out_end) {
  const char* p = in_begin;

  if (*p == '\'') {
    p++;

    // handle escape characters
    if (p < in_end && *p == '\\') p++;

    if (p < in_end) p++;

    // handle end of character literal
    if (p < in_end && *p == '\'') {
      out_begin = in_begin;
      out_end = p + 1;
      return true;
    }
  }

  return false;
}

static bool TokenizeCStyleIdentifier(const char* in_begin, const char* in_end,
                                     const char*& out_begin,
                                     const char*& out_end) {
  const char* p = in_begin;

  if ((*p >= 'a' && *p <= 'z') || (*p >= 'A' && *p <= 'Z') || *p == '_') {
    p++;

    while ((p < in_end) &&
           ((*p >= 'a' && *p <= 'z') || (*p >= 'A' && *p <= 'Z') ||
            (*p >= '0' && *p <= '9') || *p == '_'))
      p++;

    out_begin = in_begin;
    out_end = p;
    return true;
  }

  return false;
}

static bool TokenizeCStyleNumber(const char* in_begin, const char* in_end,
                                 const char*& out_begin, const char*& out_end) {
  const char* p = in_begin;

  const bool startsWithNumber = *p >= '0' && *p <= '9';

  if (*p != '+' && *p != '-' && !startsWithNumber) return false;

  p++;

  bool hasNumber = startsWithNumber;

  while (p < in_end && (*p >= '0' && *p <= '9')) {
    hasNumber = true;

    p++;
  }

  if (hasNumber == false) return false;

  bool isFloat = false;
  bool isHex = false;
  bool isBinary = false;

  if (p < in_end) {
    if (*p == '.') {
      isFloat = true;

      p++;

      while (p < in_end && (*p >= '0' && *p <= '9')) p++;
    } else if (*p == 'x' || *p == 'X') {
      // hex formatted integer of the type 0xef80

      isHex = true;

      p++;

      while (p < in_end &&
             ((*p >= '0' && *p <= '9') || (*p >= 'a' && *p <= 'f') ||
              (*p >= 'A' && *p <= 'F')))
        p++;
    } else if (*p == 'b' || *p == 'B') {
      // binary formatted integer of the type 0b01011101

      isBinary = true;

      p++;

      while (p < in_end && (*p >= '0' && *p <= '1')) p++;
    }
  }

  if (isHex == false && isBinary == false) {
    // floating point exponent
    if (p < in_end && (*p == 'e' || *p == 'E')) {
      isFloat = true;

      p++;

      if (p < in_end && (*p == '+' || *p == '-')) p++;

      bool hasDigits = false;

      while (p < in_end && (*p >= '0' && *p <= '9')) {
        hasDigits = true;

        p++;
      }

      if (hasDigits == false) return false;
    }

    // single precision floating point type
    if (p < in_end && *p == 'f') p++;
  }

  if (isFloat == false) {
    // integer size type
    while (p < in_end && (*p == 'u' || *p == 'U' || *p == 'l' || *p == 'L'))
      p++;
  }

  out_begin = in_begin;
  out_end = p;
  return true;
}

static bool TokenizeCStylePunctuation(const char* in_begin, const char* in_end,
                                      const char*& out_begin,
                                      const char*& out_end) {
  (void)in_end;

  switch (*in_begin) {
    case '[':
    case ']':
    case '{':
    case '}':
    case '!':
    case '%':
    case '^':
    case '&':
    case '*':
    case '(':
    case ')':
    case '-':
    case '+':
    case '=':
    case '~':
    case '|':
    case '<':
    case '>':
    case '?':
    case ':':
    case '/':
    case ';':
    case ',':
    case '.':
      out_begin = in_begin;
      out_end = in_begin + 1;
      return true;
  }

  return false;
}

const TextEditor::LanguageDefinition&
TextEditor::LanguageDefinition::CPlusPlus() {
  static bool inited = false;
  static LanguageDefinition langDef;
  if (!inited) {
    static const char* const cppKeywords[] = {"alignas",
                                              "alignof",
                                              "and",
                                              "and_eq",
                                              "asm",
                                              "atomic_cancel",
                                              "atomic_commit",
                                              "atomic_noexcept",
                                              "auto",
                                              "bitand",
                                              "bitor",
                                              "bool",
                                              "break",
                                              "case",
                                              "catch",
                                              "char",
                                              "char16_t",
                                              "char32_t",
                                              "class",
                                              "compl",
                                              "concept",
                                              "const",
                                              "constexpr",
                                              "const_cast",
                                              "continue",
                                              "decltype",
                                              "default",
                                              "delete",
                                              "do",
                                              "double",
                                              "dynamic_cast",
                                              "else",
                                              "enum",
                                              "explicit",
                                              "export",
                                              "extern",
                                              "false",
                                              "float",
                                              "for",
                                              "friend",
                                              "goto",
                                              "if",
                                              "import",
                                              "inline",
                                              "int",
                                              "long",
                                              "module",
                                              "mutable",
                                              "namespace",
                                              "new",
                                              "noexcept",
                                              "not",
                                              "not_eq",
                                              "nullptr",
                                              "operator",
                                              "or",
                                              "or_eq",
                                              "private",
                                              "protected",
                                              "public",
                                              "register",
                                              "reinterpret_cast",
                                              "requires",
                                              "return",
                                              "short",
                                              "signed",
                                              "sizeof",
                                              "static",
                                              "static_assert",
                                              "static_cast",
                                              "struct",
                                              "switch",
                                              "synchronized",
                                              "template",
                                              "this",
                                              "thread_local",
                                              "throw",
                                              "true",
                                              "try",
                                              "typedef",
                                              "typeid",
                                              "typename",
                                              "union",
                                              "unsigned",
                                              "using",
                                              "virtual",
                                              "void",
                                              "volatile",
                                              "wchar_t",
                                              "while",
                                              "xor",
                                              "xor_eq"};
    for (auto& k : cppKeywords) langDef.mKeywords.insert(k);

    static const char* const identifiers[] = {
        "abort",   "abs",           "acos",    "asin",          "atan",
        "atexit",  "atof",          "atoi",    "atol",          "ceil",
        "clock",   "cosh",          "ctime",   "div",           "exit",
        "fabs",    "floor",         "fmod",    "getchar",       "getenv",
        "isalnum", "isalpha",       "isdigit", "isgraph",       "ispunct",
        "isspace", "isupper",       "kbhit",   "log10",         "log2",
        "log",     "memcmp",        "modf",    "pow",           "printf",
        "sprintf", "snprintf",      "putchar", "putenv",        "puts",
        "rand",    "remove",        "rename",  "sinh",          "sqrt",
        "srand",   "strcat",        "strcmp",  "strerror",      "time",
        "tolower", "toupper",       "std",     "string",        "vector",
        "map",     "unordered_map", "set",     "unordered_set", "min",
        "max"};
    for (auto& k : identifiers) {
      Identifier id;
      id.mDeclaration = "Built-in function";
      langDef.mIdentifiers.insert(std::make_pair(std::string(k), id));
    }

    langDef.mTokenize = [](const char* in_begin, const char* in_end,
                           const char*& out_begin, const char*& out_end,
                           PaletteIndex& paletteIndex) -> bool {
      paletteIndex = PaletteIndex::Max;

      while (in_begin < in_end && isascii(*in_begin) && isblank(*in_begin))
        in_begin++;

      if (in_begin == in_end) {
        out_begin = in_end;
        out_end = in_end;
        paletteIndex = PaletteIndex::Default;
      } else if (TokenizeCStyleString(in_begin, in_end, out_begin, out_end))
        paletteIndex = PaletteIndex::String;
      else if (TokenizeCStyleCharacterLiteral(in_begin, in_end, out_begin,
                                              out_end))
        paletteIndex = PaletteIndex::CharLiteral;
      else if (TokenizeCStyleIdentifier(in_begin, in_end, out_begin, out_end))
        paletteIndex = PaletteIndex::Identifier;
      else if (TokenizeCStyleNumber(in_begin, in_end, out_begin, out_end))
        paletteIndex = PaletteIndex::Number;
      else if (TokenizeCStylePunctuation(in_begin, in_end, out_begin, out_end))
        paletteIndex = PaletteIndex::Punctuation;

      return paletteIndex != PaletteIndex::Max;
    };

    langDef.mCommentStart = "/*";
    langDef.mCommentEnd = "*/";
    langDef.mSingleLineComment = "//";

    langDef.mCaseSensitive = true;
    langDef.mAutoIndentation = true;

    langDef.mName = "C++";

    inited = true;
  }
  return langDef;
}

const TextEditor::LanguageDefinition& TextEditor::LanguageDefinition::HLSL() {
  static bool inited = false;
  static LanguageDefinition langDef;
  if (!inited) {
    static const char* const keywords[] = {
        "AppendStructuredBuffer",
        "asm",
        "asm_fragment",
        "BlendState",
        "bool",
        "break",
        "Buffer",
        "ByteAddressBuffer",
        "case",
        "cbuffer",
        "centroid",
        "class",
        "column_major",
        "compile",
        "compile_fragment",
        "CompileShader",
        "const",
        "continue",
        "ComputeShader",
        "ConsumeStructuredBuffer",
        "default",
        "DepthStencilState",
        "DepthStencilView",
        "discard",
        "do",
        "double",
        "DomainShader",
        "dword",
        "else",
        "export",
        "extern",
        "false",
        "float",
        "for",
        "fxgroup",
        "GeometryShader",
        "groupshared",
        "half",
        "Hullshader",
        "if",
        "in",
        "inline",
        "inout",
        "InputPatch",
        "int",
        "interface",
        "line",
        "lineadj",
        "linear",
        "LineStream",
        "matrix",
        "min16float",
        "min10float",
        "min16int",
        "min12int",
        "min16uint",
        "namespace",
        "nointerpolation",
        "noperspective",
        "NULL",
        "out",
        "OutputPatch",
        "packoffset",
        "pass",
        "pixelfragment",
        "PixelShader",
        "point",
        "PointStream",
        "precise",
        "RasterizerState",
        "RenderTargetView",
        "return",
        "register",
        "row_major",
        "RWBuffer",
        "RWByteAddressBuffer",
        "RWStructuredBuffer",
        "RWTexture1D",
        "RWTexture1DArray",
        "RWTexture2D",
        "RWTexture2DArray",
        "RWTexture3D",
        "sample",
        "sampler",
        "SamplerState",
        "SamplerComparisonState",
        "shared",
        "snorm",
        "stateblock",
        "stateblock_state",
        "static",
        "string",
        "struct",
        "switch",
        "StructuredBuffer",
        "tbuffer",
        "technique",
        "technique10",
        "technique11",
        "texture",
        "Texture1D",
        "Texture1DArray",
        "Texture2D",
        "Texture2DArray",
        "Texture2DMS",
        "Texture2DMSArray",
        "Texture3D",
        "TextureCube",
        "TextureCubeArray",
        "true",
        "typedef",
        "triangle",
        "triangleadj",
        "TriangleStream",
        "uint",
        "uniform",
        "unorm",
        "unsigned",
        "vector",
        "vertexfragment",
        "VertexShader",
        "void",
        "volatile",
        "while",
        "bool1",
        "bool2",
        "bool3",
        "bool4",
        "double1",
        "double2",
        "double3",
        "double4",
        "float1",
        "float2",
        "float3",
        "float4",
        "int1",
        "int2",
        "int3",
        "int4",
        "in",
        "out",
        "inout",
        "uint1",
        "uint2",
        "uint3",
        "uint4",
        "dword1",
        "dword2",
        "dword3",
        "dword4",
        "half1",
        "half2",
        "half3",
        "half4",
        "float1x1",
        "float2x1",
        "float3x1",
        "float4x1",
        "float1x2",
        "float2x2",
        "float3x2",
        "float4x2",
        "float1x3",
        "float2x3",
        "float3x3",
        "float4x3",
        "float1x4",
        "float2x4",
        "float3x4",
        "float4x4",
        "half1x1",
        "half2x1",
        "half3x1",
        "half4x1",
        "half1x2",
        "half2x2",
        "half3x2",
        "half4x2",
        "half1x3",
        "half2x3",
        "half3x3",
        "half4x3",
        "half1x4",
        "half2x4",
        "half3x4",
        "half4x4",
    };
    for (auto& k : keywords) langDef.mKeywords.insert(k);

    static const char* const identifiers[] = {
        "abort",
        "abs",
        "acos",
        "all",
        "AllMemoryBarrier",
        "AllMemoryBarrierWithGroupSync",
        "any",
        "asdouble",
        "asfloat",
        "asin",
        "asint",
        "asint",
        "asuint",
        "asuint",
        "atan",
        "atan2",
        "ceil",
        "CheckAccessFullyMapped",
        "clamp",
        "clip",
        "cos",
        "cosh",
        "countbits",
        "cross",
        "D3DCOLORtoUBYTE4",
        "ddx",
        "ddx_coarse",
        "ddx_fine",
        "ddy",
        "ddy_coarse",
        "ddy_fine",
        "degrees",
        "determinant",
        "DeviceMemoryBarrier",
        "DeviceMemoryBarrierWithGroupSync",
        "distance",
        "dot",
        "dst",
        "errorf",
        "EvaluateAttributeAtCentroid",
        "EvaluateAttributeAtSample",
        "EvaluateAttributeSnapped",
        "exp",
        "exp2",
        "f16tof32",
        "f32tof16",
        "faceforward",
        "firstbithigh",
        "firstbitlow",
        "floor",
        "fma",
        "fmod",
        "frac",
        "frexp",
        "fwidth",
        "GetRenderTargetSampleCount",
        "GetRenderTargetSamplePosition",
        "GroupMemoryBarrier",
        "GroupMemoryBarrierWithGroupSync",
        "InterlockedAdd",
        "InterlockedAnd",
        "InterlockedCompareExchange",
        "InterlockedCompareStore",
        "InterlockedExchange",
        "InterlockedMax",
        "InterlockedMin",
        "InterlockedOr",
        "InterlockedXor",
        "isfinite",
        "isinf",
        "isnan",
        "ldexp",
        "length",
        "lerp",
        "lit",
        "log",
        "log10",
        "log2",
        "mad",
        "max",
        "min",
        "modf",
        "msad4",
        "mul",
        "noise",
        "normalize",
        "pow",
        "printf",
        "Process2DQuadTessFactorsAvg",
        "Process2DQuadTessFactorsMax",
        "Process2DQuadTessFactorsMin",
        "ProcessIsolineTessFactors",
        "ProcessQuadTessFactorsAvg",
        "ProcessQuadTessFactorsMax",
        "ProcessQuadTessFactorsMin",
        "ProcessTriTessFactorsAvg",
        "ProcessTriTessFactorsMax",
        "ProcessTriTessFactorsMin",
        "radians",
        "rcp",
        "reflect",
        "refract",
        "reversebits",
        "round",
        "rsqrt",
        "saturate",
        "sign",
        "sin",
        "sincos",
        "sinh",
        "smoothstep",
        "sqrt",
        "step",
        "tan",
        "tanh",
        "tex1D",
        "tex1D",
        "tex1Dbias",
        "tex1Dgrad",
        "tex1Dlod",
        "tex1Dproj",
        "tex2D",
        "tex2D",
        "tex2Dbias",
        "tex2Dgrad",
        "tex2Dlod",
        "tex2Dproj",
        "tex3D",
        "tex3D",
        "tex3Dbias",
        "tex3Dgrad",
        "tex3Dlod",
        "tex3Dproj",
        "texCUBE",
        "texCUBE",
        "texCUBEbias",
        "texCUBEgrad",
        "texCUBElod",
        "texCUBEproj",
        "transpose",
        "trunc"};
    for (auto& k : identifiers) {
      Identifier id;
      id.mDeclaration = "Built-in function";
      langDef.mIdentifiers.insert(std::make_pair(std::string(k), id));
    }

    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("[ \\t]*#[ \\t]*[a-zA-Z_]+",
                                                  PaletteIndex::Preprocessor));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("L?\\\"(\\\\.|[^\\\"])*\\\"",
                                                  PaletteIndex::String));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("\\'\\\\?[^\\']\\'",
                                                  PaletteIndex::CharLiteral));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "[+-]?([0-9]+([.][0-9]*)?|[.][0-9]+)([eE][+-]?[0-9]+)?[fF]?",
            PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("[+-]?[0-9]+[Uu]?[lL]?[lL]?",
                                                  PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("0[0-7]+[Uu]?[lL]?[lL]?",
                                                  PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "0[xX][0-9a-fA-F]+[uU]?[lL]?[lL]?", PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("[a-zA-Z_][a-zA-Z0-9_]*",
                                                  PaletteIndex::Identifier));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "[\\[\\]\\{\\}\\!\\%\\^\\&\\*\\(\\)\\-\\+\\=\\~\\|\\<\\>\\?\\/"
            "\\;\\,\\.]",
            PaletteIndex::Punctuation));

    langDef.mCommentStart = "/*";
    langDef.mCommentEnd = "*/";
    langDef.mSingleLineComment = "//";

    langDef.mCaseSensitive = true;
    langDef.mAutoIndentation = true;

    langDef.mName = "HLSL";

    inited = true;
  }
  return langDef;
}

const TextEditor::LanguageDefinition& TextEditor::LanguageDefinition::GLSL() {
  static bool inited = false;
  static LanguageDefinition langDef;
  if (!inited) {
    static const char* const keywords[] = {
        "auto",       "break",     "case",           "char",
        "const",      "continue",  "default",        "do",
        "double",     "else",      "enum",           "extern",
        "float",      "for",       "goto",           "if",
        "inline",     "int",       "long",           "register",
        "restrict",   "return",    "short",          "signed",
        "sizeof",     "static",    "struct",         "switch",
        "typedef",    "union",     "unsigned",       "void",
        "volatile",   "while",     "_Alignas",       "_Alignof",
        "_Atomic",    "_Bool",     "_Complex",       "_Generic",
        "_Imaginary", "_Noreturn", "_Static_assert", "_Thread_local"};
    for (auto& k : keywords) langDef.mKeywords.insert(k);

    static const char* const identifiers[] = {
        "abort",   "abs",     "acos",    "asin",     "atan",    "atexit",
        "atof",    "atoi",    "atol",    "ceil",     "clock",   "cosh",
        "ctime",   "div",     "exit",    "fabs",     "floor",   "fmod",
        "getchar", "getenv",  "isalnum", "isalpha",  "isdigit", "isgraph",
        "ispunct", "isspace", "isupper", "kbhit",    "log10",   "log2",
        "log",     "memcmp",  "modf",    "pow",      "putchar", "putenv",
        "puts",    "rand",    "remove",  "rename",   "sinh",    "sqrt",
        "srand",   "strcat",  "strcmp",  "strerror", "time",    "tolower",
        "toupper"};
    for (auto& k : identifiers) {
      Identifier id;
      id.mDeclaration = "Built-in function";
      langDef.mIdentifiers.insert(std::make_pair(std::string(k), id));
    }

    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("[ \\t]*#[ \\t]*[a-zA-Z_]+",
                                                  PaletteIndex::Preprocessor));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("L?\\\"(\\\\.|[^\\\"])*\\\"",
                                                  PaletteIndex::String));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("\\'\\\\?[^\\']\\'",
                                                  PaletteIndex::CharLiteral));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "[+-]?([0-9]+([.][0-9]*)?|[.][0-9]+)([eE][+-]?[0-9]+)?[fF]?",
            PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("[+-]?[0-9]+[Uu]?[lL]?[lL]?",
                                                  PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("0[0-7]+[Uu]?[lL]?[lL]?",
                                                  PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "0[xX][0-9a-fA-F]+[uU]?[lL]?[lL]?", PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("[a-zA-Z_][a-zA-Z0-9_]*",
                                                  PaletteIndex::Identifier));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "[\\[\\]\\{\\}\\!\\%\\^\\&\\*\\(\\)\\-\\+\\=\\~\\|\\<\\>\\?\\/"
            "\\;\\,\\.]",
            PaletteIndex::Punctuation));

    langDef.mCommentStart = "/*";
    langDef.mCommentEnd = "*/";
    langDef.mSingleLineComment = "//";

    langDef.mCaseSensitive = true;
    langDef.mAutoIndentation = true;

    langDef.mName = "GLSL";

    inited = true;
  }
  return langDef;
}

const TextEditor::LanguageDefinition& TextEditor::LanguageDefinition::C() {
  static bool inited = false;
  static LanguageDefinition langDef;
  if (!inited) {
    static const char* const keywords[] = {
        "auto",       "break",     "case",           "char",
        "const",      "continue",  "default",        "do",
        "double",     "else",      "enum",           "extern",
        "float",      "for",       "goto",           "if",
        "inline",     "int",       "long",           "register",
        "restrict",   "return",    "short",          "signed",
        "sizeof",     "static",    "struct",         "switch",
        "typedef",    "union",     "unsigned",       "void",
        "volatile",   "while",     "_Alignas",       "_Alignof",
        "_Atomic",    "_Bool",     "_Complex",       "_Generic",
        "_Imaginary", "_Noreturn", "_Static_assert", "_Thread_local"};
    for (auto& k : keywords) langDef.mKeywords.insert(k);

    static const char* const identifiers[] = {
        "abort",   "abs",     "acos",    "asin",     "atan",    "atexit",
        "atof",    "atoi",    "atol",    "ceil",     "clock",   "cosh",
        "ctime",   "div",     "exit",    "fabs",     "floor",   "fmod",
        "getchar", "getenv",  "isalnum", "isalpha",  "isdigit", "isgraph",
        "ispunct", "isspace", "isupper", "kbhit",    "log10",   "log2",
        "log",     "memcmp",  "modf",    "pow",      "putchar", "putenv",
        "puts",    "rand",    "remove",  "rename",   "sinh",    "sqrt",
        "srand",   "strcat",  "strcmp",  "strerror", "time",    "tolower",
        "toupper"};
    for (auto& k : identifiers) {
      Identifier id;
      id.mDeclaration = "Built-in function";
      langDef.mIdentifiers.insert(std::make_pair(std::string(k), id));
    }

    langDef.mTokenize = [](const char* in_begin, const char* in_end,
                           const char*& out_begin, const char*& out_end,
                           PaletteIndex& paletteIndex) -> bool {
      paletteIndex = PaletteIndex::Max;

      while (in_begin < in_end && isascii(*in_begin) && isblank(*in_begin))
        in_begin++;

      if (in_begin == in_end) {
        out_begin = in_end;
        out_end = in_end;
        paletteIndex = PaletteIndex::Default;
      } else if (TokenizeCStyleString(in_begin, in_end, out_begin, out_end))
        paletteIndex = PaletteIndex::String;
      else if (TokenizeCStyleCharacterLiteral(in_begin, in_end, out_begin,
                                              out_end))
        paletteIndex = PaletteIndex::CharLiteral;
      else if (TokenizeCStyleIdentifier(in_begin, in_end, out_begin, out_end))
        paletteIndex = PaletteIndex::Identifier;
      else if (TokenizeCStyleNumber(in_begin, in_end, out_begin, out_end))
        paletteIndex = PaletteIndex::Number;
      else if (TokenizeCStylePunctuation(in_begin, in_end, out_begin, out_end))
        paletteIndex = PaletteIndex::Punctuation;

      return paletteIndex != PaletteIndex::Max;
    };

    langDef.mCommentStart = "/*";
    langDef.mCommentEnd = "*/";
    langDef.mSingleLineComment = "//";

    langDef.mCaseSensitive = true;
    langDef.mAutoIndentation = true;

    langDef.mName = "C";

    inited = true;
  }
  return langDef;
}

const TextEditor::LanguageDefinition& TextEditor::LanguageDefinition::SQL() {
  static bool inited = false;
  static LanguageDefinition langDef;
  if (!inited) {
    static const char* const keywords[] = {"ADD",
                                           "EXCEPT",
                                           "PERCENT",
                                           "ALL",
                                           "EXEC",
                                           "PLAN",
                                           "ALTER",
                                           "EXECUTE",
                                           "PRECISION",
                                           "AND",
                                           "EXISTS",
                                           "PRIMARY",
                                           "ANY",
                                           "EXIT",
                                           "PRINT",
                                           "AS",
                                           "FETCH",
                                           "PROC",
                                           "ASC",
                                           "FILE",
                                           "PROCEDURE",
                                           "AUTHORIZATION",
                                           "FILLFACTOR",
                                           "PUBLIC",
                                           "BACKUP",
                                           "FOR",
                                           "RAISERROR",
                                           "BEGIN",
                                           "FOREIGN",
                                           "READ",
                                           "BETWEEN",
                                           "FREETEXT",
                                           "READTEXT",
                                           "BREAK",
                                           "FREETEXTTABLE",
                                           "RECONFIGURE",
                                           "BROWSE",
                                           "FROM",
                                           "REFERENCES",
                                           "BULK",
                                           "FULL",
                                           "REPLICATION",
                                           "BY",
                                           "FUNCTION",
                                           "RESTORE",
                                           "CASCADE",
                                           "GOTO",
                                           "RESTRICT",
                                           "CASE",
                                           "GRANT",
                                           "RETURN",
                                           "CHECK",
                                           "GROUP",
                                           "REVOKE",
                                           "CHECKPOINT",
                                           "HAVING",
                                           "RIGHT",
                                           "CLOSE",
                                           "HOLDLOCK",
                                           "ROLLBACK",
                                           "CLUSTERED",
                                           "IDENTITY",
                                           "ROWCOUNT",
                                           "COALESCE",
                                           "IDENTITY_INSERT",
                                           "ROWGUIDCOL",
                                           "COLLATE",
                                           "IDENTITYCOL",
                                           "RULE",
                                           "COLUMN",
                                           "IF",
                                           "SAVE",
                                           "COMMIT",
                                           "IN",
                                           "SCHEMA",
                                           "COMPUTE",
                                           "INDEX",
                                           "SELECT",
                                           "CONSTRAINT",
                                           "INNER",
                                           "SESSION_USER",
                                           "CONTAINS",
                                           "INSERT",
                                           "SET",
                                           "CONTAINSTABLE",
                                           "INTERSECT",
                                           "SETUSER",
                                           "CONTINUE",
                                           "INTO",
                                           "SHUTDOWN",
                                           "CONVERT",
                                           "IS",
                                           "SOME",
                                           "CREATE",
                                           "JOIN",
                                           "STATISTICS",
                                           "CROSS",
                                           "KEY",
                                           "SYSTEM_USER",
                                           "CURRENT",
                                           "KILL",
                                           "TABLE",
                                           "CURRENT_DATE",
                                           "LEFT",
                                           "TEXTSIZE",
                                           "CURRENT_TIME",
                                           "LIKE",
                                           "THEN",
                                           "CURRENT_TIMESTAMP",
                                           "LINENO",
                                           "TO",
                                           "CURRENT_USER",
                                           "LOAD",
                                           "TOP",
                                           "CURSOR",
                                           "NATIONAL",
                                           "TRAN",
                                           "DATABASE",
                                           "NOCHECK",
                                           "TRANSACTION",
                                           "DBCC",
                                           "NONCLUSTERED",
                                           "TRIGGER",
                                           "DEALLOCATE",
                                           "NOT",
                                           "TRUNCATE",
                                           "DECLARE",
                                           "NULL",
                                           "TSEQUAL",
                                           "DEFAULT",
                                           "NULLIF",
                                           "UNION",
                                           "DELETE",
                                           "OF",
                                           "UNIQUE",
                                           "DENY",
                                           "OFF",
                                           "UPDATE",
                                           "DESC",
                                           "OFFSETS",
                                           "UPDATETEXT",
                                           "DISK",
                                           "ON",
                                           "USE",
                                           "DISTINCT",
                                           "OPEN",
                                           "USER",
                                           "DISTRIBUTED",
                                           "OPENDATASOURCE",
                                           "VALUES",
                                           "DOUBLE",
                                           "OPENQUERY",
                                           "VARYING",
                                           "DROP",
                                           "OPENROWSET",
                                           "VIEW",
                                           "DUMMY",
                                           "OPENXML",
                                           "WAITFOR",
                                           "DUMP",
                                           "OPTION",
                                           "WHEN",
                                           "ELSE",
                                           "OR",
                                           "WHERE",
                                           "END",
                                           "ORDER",
                                           "WHILE",
                                           "ERRLVL",
                                           "OUTER",
                                           "WITH",
                                           "ESCAPE",
                                           "OVER",
                                           "WRITETEXT"};

    for (auto& k : keywords) langDef.mKeywords.insert(k);

    static const char* const identifiers[] = {"ABS",
                                              "ACOS",
                                              "ADD_MONTHS",
                                              "ASCII",
                                              "ASCIISTR",
                                              "ASIN",
                                              "ATAN",
                                              "ATAN2",
                                              "AVG",
                                              "BFILENAME",
                                              "BIN_TO_NUM",
                                              "BITAND",
                                              "CARDINALITY",
                                              "CASE",
                                              "CAST",
                                              "CEIL",
                                              "CHARTOROWID",
                                              "CHR",
                                              "COALESCE",
                                              "COMPOSE",
                                              "CONCAT",
                                              "CONVERT",
                                              "CORR",
                                              "COS",
                                              "COSH",
                                              "COUNT",
                                              "COVAR_POP",
                                              "COVAR_SAMP",
                                              "CUME_DIST",
                                              "CURRENT_DATE",
                                              "CURRENT_TIMESTAMP",
                                              "DBTIMEZONE",
                                              "DECODE",
                                              "DECOMPOSE",
                                              "DENSE_RANK",
                                              "DUMP",
                                              "EMPTY_BLOB",
                                              "EMPTY_CLOB",
                                              "EXP",
                                              "EXTRACT",
                                              "FIRST_VALUE",
                                              "FLOOR",
                                              "FROM_TZ",
                                              "GREATEST",
                                              "GROUP_ID",
                                              "HEXTORAW",
                                              "INITCAP",
                                              "INSTR",
                                              "INSTR2",
                                              "INSTR4",
                                              "INSTRB",
                                              "INSTRC",
                                              "LAG",
                                              "LAST_DAY",
                                              "LAST_VALUE",
                                              "LEAD",
                                              "LEAST",
                                              "LENGTH",
                                              "LENGTH2",
                                              "LENGTH4",
                                              "LENGTHB",
                                              "LENGTHC",
                                              "LISTAGG",
                                              "LN",
                                              "LNNVL",
                                              "LOCALTIMESTAMP",
                                              "LOG",
                                              "LOWER",
                                              "LPAD",
                                              "LTRIM",
                                              "MAX",
                                              "MEDIAN",
                                              "MIN",
                                              "MOD",
                                              "MONTHS_BETWEEN",
                                              "NANVL",
                                              "NCHR",
                                              "NEW_TIME",
                                              "NEXT_DAY",
                                              "NTH_VALUE",
                                              "NULLIF",
                                              "NUMTODSINTERVAL",
                                              "NUMTOYMINTERVAL",
                                              "NVL",
                                              "NVL2",
                                              "POWER",
                                              "RANK",
                                              "RAWTOHEX",
                                              "REGEXP_COUNT",
                                              "REGEXP_INSTR",
                                              "REGEXP_REPLACE",
                                              "REGEXP_SUBSTR",
                                              "REMAINDER",
                                              "REPLACE",
                                              "ROUND",
                                              "ROWNUM",
                                              "RPAD",
                                              "RTRIM",
                                              "SESSIONTIMEZONE",
                                              "SIGN",
                                              "SIN",
                                              "SINH",
                                              "SOUNDEX",
                                              "SQRT",
                                              "STDDEV",
                                              "SUBSTR",
                                              "SUM",
                                              "SYS_CONTEXT",
                                              "SYSDATE",
                                              "SYSTIMESTAMP",
                                              "TAN",
                                              "TANH",
                                              "TO_CHAR",
                                              "TO_CLOB",
                                              "TO_DATE",
                                              "TO_DSINTERVAL",
                                              "TO_LOB",
                                              "TO_MULTI_BYTE",
                                              "TO_NCLOB",
                                              "TO_NUMBER",
                                              "TO_SINGLE_BYTE",
                                              "TO_TIMESTAMP",
                                              "TO_TIMESTAMP_TZ",
                                              "TO_YMINTERVAL",
                                              "TRANSLATE",
                                              "TRIM",
                                              "TRUNC",
                                              "TZ_OFFSET",
                                              "UID",
                                              "UPPER",
                                              "USER",
                                              "USERENV",
                                              "VAR_POP",
                                              "VAR_SAMP",
                                              "VARIANCE",
                                              "VSIZE "};
    for (auto& k : identifiers) {
      Identifier id;
      id.mDeclaration = "Built-in function";
      langDef.mIdentifiers.insert(std::make_pair(std::string(k), id));
    }

    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("L?\\\"(\\\\.|[^\\\"])*\\\"",
                                                  PaletteIndex::String));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("\\\'[^\\\']*\\\'",
                                                  PaletteIndex::String));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "[+-]?([0-9]+([.][0-9]*)?|[.][0-9]+)([eE][+-]?[0-9]+)?[fF]?",
            PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("[+-]?[0-9]+[Uu]?[lL]?[lL]?",
                                                  PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("0[0-7]+[Uu]?[lL]?[lL]?",
                                                  PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "0[xX][0-9a-fA-F]+[uU]?[lL]?[lL]?", PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("[a-zA-Z_][a-zA-Z0-9_]*",
                                                  PaletteIndex::Identifier));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "[\\[\\]\\{\\}\\!\\%\\^\\&\\*\\(\\)\\-\\+\\=\\~\\|\\<\\>\\?\\/"
            "\\;\\,\\.]",
            PaletteIndex::Punctuation));

    langDef.mCommentStart = "/*";
    langDef.mCommentEnd = "*/";
    langDef.mSingleLineComment = "//";

    langDef.mCaseSensitive = false;
    langDef.mAutoIndentation = false;

    langDef.mName = "SQL";

    inited = true;
  }
  return langDef;
}

const TextEditor::LanguageDefinition&
TextEditor::LanguageDefinition::AngelScript() {
  static bool inited = false;
  static LanguageDefinition langDef;
  if (!inited) {
    static const char* const keywords[] = {
        "and",       "abstract", "auto",      "bool",      "break",
        "case",      "cast",     "class",     "const",     "continue",
        "default",   "do",       "double",    "else",      "enum",
        "false",     "final",    "float",     "for",       "from",
        "funcdef",   "function", "get",       "if",        "import",
        "in",        "inout",    "int",       "interface", "int8",
        "int16",     "int32",    "int64",     "is",        "mixin",
        "namespace", "not",      "null",      "or",        "out",
        "override",  "private",  "protected", "return",    "set",
        "shared",    "super",    "switch",    "this ",     "true",
        "typedef",   "uint",     "uint8",     "uint16",    "uint32",
        "uint64",    "void",     "while",     "xor"};

    for (auto& k : keywords) langDef.mKeywords.insert(k);

    static const char* const identifiers[] = {
        "cos",         "sin",         "tab",      "acos",        "asin",
        "atan",        "atan2",       "cosh",     "sinh",        "tanh",
        "log",         "log10",       "pow",      "sqrt",        "abs",
        "ceil",        "floor",       "fraction", "closeTo",     "fpFromIEEE",
        "fpToIEEE",    "complex",     "opEquals", "opAddAssign", "opSubAssign",
        "opMulAssign", "opDivAssign", "opAdd",    "opSub",       "opMul",
        "opDiv"};
    for (auto& k : identifiers) {
      Identifier id;
      id.mDeclaration = "Built-in function";
      langDef.mIdentifiers.insert(std::make_pair(std::string(k), id));
    }

    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("L?\\\"(\\\\.|[^\\\"])*\\\"",
                                                  PaletteIndex::String));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("\\'\\\\?[^\\']\\'",
                                                  PaletteIndex::String));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "[+-]?([0-9]+([.][0-9]*)?|[.][0-9]+)([eE][+-]?[0-9]+)?[fF]?",
            PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("[+-]?[0-9]+[Uu]?[lL]?[lL]?",
                                                  PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("0[0-7]+[Uu]?[lL]?[lL]?",
                                                  PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "0[xX][0-9a-fA-F]+[uU]?[lL]?[lL]?", PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("[a-zA-Z_][a-zA-Z0-9_]*",
                                                  PaletteIndex::Identifier));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "[\\[\\]\\{\\}\\!\\%\\^\\&\\*\\(\\)\\-\\+\\=\\~\\|\\<\\>\\?\\/"
            "\\;\\,\\.]",
            PaletteIndex::Punctuation));

    langDef.mCommentStart = "/*";
    langDef.mCommentEnd = "*/";
    langDef.mSingleLineComment = "//";

    langDef.mCaseSensitive = true;
    langDef.mAutoIndentation = true;

    langDef.mName = "AngelScript";

    inited = true;
  }
  return langDef;
}

const TextEditor::LanguageDefinition& TextEditor::LanguageDefinition::Lua() {
  static bool inited = false;
  static LanguageDefinition langDef;
  if (!inited) {
    static const char* const keywords[] = {
        "and", "break",    "do",     "",     "else", "elseif", "end",  "false",
        "for", "function", "if",     "in",   "",     "local",  "nil",  "not",
        "or",  "repeat",   "return", "then", "true", "until",  "while"};

    for (auto& k : keywords) langDef.mKeywords.insert(k);

    static const char* const identifiers[] = {"assert",       "collectgarbage",
                                              "dofile",       "error",
                                              "getmetatable", "ipairs",
                                              "loadfile",     "load",
                                              "loadstring",   "next",
                                              "pairs",        "pcall",
                                              "print",        "rawequal",
                                              "rawlen",       "rawget",
                                              "rawset",       "select",
                                              "setmetatable", "tonumber",
                                              "tostring",     "type",
                                              "xpcall",       "_G",
                                              "_VERSION",     "arshift",
                                              "band",         "bnot",
                                              "bor",          "bxor",
                                              "btest",        "extract",
                                              "lrotate",      "lshift",
                                              "replace",      "rrotate",
                                              "rshift",       "create",
                                              "resume",       "running",
                                              "status",       "wrap",
                                              "yield",        "isyieldable",
                                              "debug",        "getuservalue",
                                              "gethook",      "getinfo",
                                              "getlocal",     "getregistry",
                                              "getmetatable", "getupvalue",
                                              "upvaluejoin",  "upvalueid",
                                              "setuservalue", "sethook",
                                              "setlocal",     "setmetatable",
                                              "setupvalue",   "traceback",
                                              "close",        "flush",
                                              "input",        "lines",
                                              "open",         "output",
                                              "popen",        "read",
                                              "tmpfile",      "type",
                                              "write",        "close",
                                              "flush",        "lines",
                                              "read",         "seek",
                                              "setvbuf",      "write",
                                              "__gc",         "__tostring",
                                              "abs",          "acos",
                                              "asin",         "atan",
                                              "ceil",         "cos",
                                              "deg",          "exp",
                                              "tointeger",    "floor",
                                              "fmod",         "ult",
                                              "log",          "max",
                                              "min",          "modf",
                                              "rad",          "random",
                                              "randomseed",   "sin",
                                              "sqrt",         "string",
                                              "tan",          "type",
                                              "atan2",        "cosh",
                                              "sinh",         "tanh",
                                              "pow",          "frexp",
                                              "ldexp",        "log10",
                                              "pi",           "huge",
                                              "maxinteger",   "mininteger",
                                              "loadlib",      "searchpath",
                                              "seeall",       "preload",
                                              "cpath",        "path",
                                              "searchers",    "loaded",
                                              "module",       "require",
                                              "clock",        "date",
                                              "difftime",     "execute",
                                              "exit",         "getenv",
                                              "remove",       "rename",
                                              "setlocale",    "time",
                                              "tmpname",      "byte",
                                              "char",         "dump",
                                              "find",         "format",
                                              "gmatch",       "gsub",
                                              "len",          "lower",
                                              "match",        "rep",
                                              "reverse",      "sub",
                                              "upper",        "pack",
                                              "packsize",     "unpack",
                                              "concat",       "maxn",
                                              "insert",       "pack",
                                              "unpack",       "remove",
                                              "move",         "sort",
                                              "offset",       "codepoint",
                                              "char",         "len",
                                              "codes",        "charpattern",
                                              "coroutine",    "table",
                                              "io",           "os",
                                              "string",       "utf8",
                                              "bit32",        "math",
                                              "debug",        "package"};
    for (auto& k : identifiers) {
      Identifier id;
      id.mDeclaration = "Built-in function";
      langDef.mIdentifiers.insert(std::make_pair(std::string(k), id));
    }

    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("L?\\\"(\\\\.|[^\\\"])*\\\"",
                                                  PaletteIndex::String));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("\\\'[^\\\']*\\\'",
                                                  PaletteIndex::String));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "0[xX][0-9a-fA-F]+[uU]?[lL]?[lL]?", PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "[+-]?([0-9]+([.][0-9]*)?|[.][0-9]+)([eE][+-]?[0-9]+)?[fF]?",
            PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("[+-]?[0-9]+[Uu]?[lL]?[lL]?",
                                                  PaletteIndex::Number));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>("[a-zA-Z_][a-zA-Z0-9_]*",
                                                  PaletteIndex::Identifier));
    langDef.mTokenRegexStrings.push_back(
        std::make_pair<std::string, PaletteIndex>(
            "[\\[\\]\\{\\}\\!\\%\\^\\&\\*\\(\\)\\-\\+\\=\\~\\|\\<\\>\\?\\/"
            "\\;\\,\\.]",
            PaletteIndex::Punctuation));

    langDef.mCommentStart = "--[[";
    langDef.mCommentEnd = "]]";
    langDef.mSingleLineComment = "--";

    langDef.mCaseSensitive = true;
    langDef.mAutoIndentation = false;

    langDef.mName = "Lua";

    inited = true;
  }
  return langDef;
}