Add custom syntax highlighter and optimize

include/syntax/parser.h

@@ -0,0 +1,33 @@
+#include "syntax/decl.h"
+
+struct Parser {
+  Knot *root;
+  std::shared_mutex *knot_mutex;
+  std::string lang;
+  std::shared_ptr<void> (*parse_func)(std::vector<Token> *tokens,
+                                      std::shared_ptr<void> in_state,
+                                      const char *text, uint32_t len);
+  bool (*state_match_func)(std::shared_ptr<void> state_1,
+                           std::shared_ptr<void> state_2);
+  std::atomic<uint32_t> scroll_max{UINT32_MAX - 2048};
+  std::mutex mutex;
+  std::mutex data_mutex;
+  std::vector<LineData> line_data;
+  std::set<uint32_t> dirty_lines;
+
+  Parser(Knot *n_root, std::shared_mutex *n_knot_mutex, std::string n_lang,
+         uint32_t n_scroll_max);
+  void edit(Knot *n_root, uint32_t start_line, uint32_t old_end_line,
+            uint32_t new_end_line);
+  void work();
+  void scroll(uint32_t line);
+  uint8_t get_type(Coord c) {
+    if (c.row >= line_data.size())
+      return 0;
+    const LineData &line = line_data[c.row];
+    for (const Token &t : line.tokens)
+      if (t.start <= c.col && c.col < t.end)
+        return t.type;
+    return 0;
+  }
+};