refactor: adjust code structure

1 files changed, 135 insertions, 0 deletions

diff --git a/src/render/utils.cc b/src/render/utils.cc
new file mode 100644
index 0000000..9c6610a
--- /dev/null
+++ b/src/render/utils.cc
@@ -0,0 +1,135 @@
+/*
+ * Ricochet - A minimalist CLI web browser for fast, distraction-free navigation.
+ * Copyright (C) 2026  Richard Qin
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+#include "ricochet/render/utils.hh"
+
+#include <array>
+#include <cstdint>
+#include <stdexcept>
+
+namespace ricochet::render {
+
+std::string decode_entities( std::string text )
+{
+  constexpr std::array<std::pair<std::string_view, std::string_view>, 25> entities
+    = { { { "&nbsp;", " " },   { "&lt;", "<" },     { "&gt;", ">" },     { "&amp;", "&" },   { "&quot;", "\"" },
+          { "&apos;", "'" },   { "&copy;", "©" },   { "&reg;", "®" },    { "&trade;", "™" }, { "&euro;", "€" },
+          { "&pound;", "£" },  { "&yen;", "¥" },    { "&cent;", "¢" },   { "&sect;", "§" },  { "&para;", "¶" },
+          { "&hellip;", "…" }, { "&dagger;", "†" }, { "&Dagger;", "‡" }, { "&bull;", "•" },  { "&prime;", "′" },
+          { "&Prime;", "″" },  { "&lsaquo;", "‹" }, { "&rsaquo;", "›" }, { "&oline;", "‾" }, { "&frasl;", "⁄" } } };
+
+  for ( const auto& [entity, replacement] : entities ) {
+    std::size_t pos = 0;
+    while ( ( pos = text.find( entity, pos ) ) != std::string::npos ) {
+      text.replace( pos, entity.length(), replacement );
+      pos += replacement.length();
+    }
+  }
+
+  std::size_t pos = 0;
+  while ( ( pos = text.find( "&#", pos ) ) != std::string::npos ) {
+    const std::size_t end = text.find( ';', pos );
+    if ( end != std::string::npos && end - pos < 10 ) {
+      const std::string code = text.substr( pos + 2, end - pos - 2 );
+      try {
+        std::uint32_t cp = 0;
+        if ( !code.empty() && ( code[0] == 'x' || code[0] == 'X' ) ) {
+          cp = std::stoul( code.substr( 1 ), nullptr, 16 );
+        } else {
+          cp = std::stoul( code );
+        }
+        if ( cp < 128 ) {
+          text.replace( pos, end - pos + 1, 1, static_cast<char>( cp ) );
+          continue;
+        }
+      } catch ( const std::invalid_argument& ) {
+        (void)0;
+      } catch ( const std::out_of_range& ) {
+        (void)0;
+      }
+    }
+    pos++;
+  }
+  return text;
+}
+
+std::string extract_attr( const std::string& tag_name, std::string_view attr_name )
+{
+  std::string match = " " + std::string( attr_name ) + "=";
+  std::size_t pos = tag_name.find( match );
+
+  if ( pos == std::string::npos ) {
+    match = std::string( attr_name ) + "=";
+    if ( !tag_name.starts_with( match ) ) {
+      return "";
+    }
+    pos = 0;
+  } else {
+    pos += 1;
+  }
+
+  pos += attr_name.length() + 1;
+  if ( pos >= tag_name.length() ) {
+    return "";
+  }
+
+  const char quote = tag_name[pos];
+  if ( quote == '"' || quote == '\'' ) {
+    const std::size_t end = tag_name.find( quote, pos + 1 );
+    if ( end != std::string::npos ) {
+      return tag_name.substr( pos + 1, end - pos - 1 );
+    }
+    return "";
+  }
+
+  const std::size_t end = tag_name.find_first_of( " >/", pos );
+  return tag_name.substr( pos, ( end == std::string::npos ) ? std::string::npos : end - pos );
+}
+
+std::size_t get_visible_length( std::string_view str )
+{
+  std::size_t len = 0;
+  bool in_ansi = false;
+  for ( std::size_t i = 0; i < str.length(); ++i ) {
+    const auto c = static_cast<unsigned char>( str[i] );
+    if ( c == 0x1B ) {
+      in_ansi = true;
+    } else if ( in_ansi && c == 'm' ) {
+      in_ansi = false;
+    } else if ( !in_ansi ) {
+      if ( ( c & 0x80 ) == 0 || ( c & 0xE0 ) == 0xC0 ) {
+        len += 1;
+      } else if ( ( c & 0xF0 ) == 0xE0 || ( c & 0xF8 ) == 0xF0 ) {
+        len += 2;
+      }
+    }
+  }
+  return len;
+}
+
+bool is_ignored_tag( std::string_view tag )
+{
+  return tag == "head" || tag == "style" || tag == "script" || tag == "meta" || tag == "title" || tag == "link";
+}
+
+bool is_heading_tag( std::string_view tag )
+{
+  return tag == "h1" || tag == "h2" || tag == "h3" || tag == "h4";
+}
+
+} // namespace ricochet::render