text: /*
   * Copyright (c) 2020, the SerenityOS developers.
   * All rights reserved.
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions are met:
   *
   * 1. Redistributions of source code must retain the above copyright notice, this
   *    list of conditions and the following disclaimer.
   *
   * 2. Redistributions in binary form must reproduce the above copyright notice,
   *    this list of conditions and the following disclaimer in the documentation
   *    and/or other materials provided with the distribution.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
   * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
   * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
   * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
   * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
   * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
   */
  
  #include <LibGUI/JSSyntaxHighlighter.h>
  #include <LibGUI/TextEditor.h>
  #include <LibGfx/Font.h>
  #include <LibGfx/Palette.h>
  #include <LibJS/Lexer.h>
  #include <LibJS/Token.h>
  
  namespace GUI {
  
  static TextStyle style_for_token_type(Gfx::Palette palette, JS::TokenType type)
  {
      switch (JS::Token::category(type)) {
      case JS::TokenCategory::Invalid:
          return { palette.syntax_comment() };
      case JS::TokenCategory::Number:
          return { palette.syntax_number() };
      case JS::TokenCategory::String:
          return { palette.syntax_string() };
      case JS::TokenCategory::Punctuation:
          return { palette.syntax_punctuation() };
      case JS::TokenCategory::Operator:
          return { palette.syntax_operator() };
      case JS::TokenCategory::Keyword:
          return { palette.syntax_keyword(), &Gfx::Font::default_bold_fixed_width_font() };
      case JS::TokenCategory::ControlKeyword:
          return { palette.syntax_control_keyword(), &Gfx::Font::default_bold_fixed_width_font() };
      case JS::TokenCategory::Identifier:
          return { palette.syntax_identifier() };
      default:
          return { palette.base_text() };
      }
  }
  
  bool JSSyntaxHighlighter::is_identifier(void* token) const
  {
      auto js_token = static_cast<JS::TokenType>(reinterpret_cast<size_t>(token));
      return js_token == JS::TokenType::Identifier;
  }
  
  bool JSSyntaxHighlighter::is_navigatable([[maybe_unused]] void* token) const
  {
      return false;
  }
  
  void JSSyntaxHighlighter::rehighlight(Gfx::Palette palette)
  {
      ASSERT(m_editor);
      auto text = m_editor->text();
  
      JS::Lexer lexer(text);
  
      Vector<GUI::TextDocumentSpan> spans;
      GUI::TextPosition position { 0, 0 };
      GUI::TextPosition start { 0, 0 };
  
      auto advance_position = [&position](char ch) {
          if (ch == '\n') {
              position.set_line(position.line() + 1);
              position.set_column(0);
          } else
              position.set_column(position.column() + 1);
      };
  
      auto append_token = [&](StringView str, const JS::Token& token, bool is_trivia) {
          if (str.is_empty())
              return;
  
          start = position;
          for (size_t i = 0; i < str.length() - 1; ++i)
              advance_position(str[i]);
  
          GUI::TextDocumentSpan span;
          span.range.set_start(start);
          span.range.set_end({ position.line(), position.column() });
          auto type = is_trivia ? JS::TokenType::Invalid : token.type();
          auto style = style_for_token_type(palette, type);
          span.color = style.color;
          span.font = style.font;
          span.is_skippable = is_trivia;
          span.data = reinterpret_cast<void*>(static_cast<size_t>(type));
          spans.append(span);
          advance_position(str[str.length() - 1]);
  
  #ifdef DEBUG_SYNTAX_HIGHLIGHTING
          dbg() << token.name() << (is_trivia ? " (trivia) @ \"" : " @ \"") << token.value() << "\" "
                << span.range.start().line() << ":" << span.range.start().column() << " - "
                << span.range.end().line() << ":" << span.range.end().column();
  #endif
      };
  
      bool was_eof = false;
      for (auto token = lexer.next(); !was_eof; token = lexer.next()) {
          append_token(token.trivia(), token, true);
          append_token(token.value(), token, false);
  
          if (token.type() == JS::TokenType::Eof)
              was_eof = true;
      }
  
      m_editor->document().set_spans(spans);
  
      m_has_brace_buddies = false;
      highlight_matching_token_pair();
  
      m_editor->update();
  }
  
  Vector<SyntaxHighlighter::MatchingTokenPair> JSSyntaxHighlighter::matching_token_pairs() const
  {
      static Vector<SyntaxHighlighter::MatchingTokenPair> pairs;
      if (pairs.is_empty()) {
          pairs.append({ reinterpret_cast<void*>(JS::TokenType::CurlyOpen), reinterpret_cast<void*>(JS::TokenType::CurlyClose) });
          pairs.append({ reinterpret_cast<void*>(JS::TokenType::ParenOpen), reinterpret_cast<void*>(JS::TokenType::ParenClose) });
          pairs.append({ reinterpret_cast<void*>(JS::TokenType::BracketOpen), reinterpret_cast<void*>(JS::TokenType::BracketClose) });
      }
      return pairs;
  }
  
  bool JSSyntaxHighlighter::token_types_equal(void* token1, void* token2) const
  {
      return static_cast<JS::TokenType>(reinterpret_cast<size_t>(token1)) == static_cast<JS::TokenType>(reinterpret_cast<size_t>(token2));
  }
  
  JSSyntaxHighlighter::~JSSyntaxHighlighter()
  {
  }
  
  }
  