Improve highlighting structure

- switched to a sparse delta based map
- true lazy-loading to avoid any unneccessary allocations
- fixed windows management api

include/syntax/decl.h

@@ -6,6 +6,8 @@
 #include "pch.h"
 #include "syntax/trie.h"
 
+#define MAX_LINES_LOOKBEHIND 80
+
 struct Highlight {
   uint32_t fg{0xFFFFFF};
   uint32_t bg{0x000000};
@@ -35,10 +37,23 @@ struct Token {
   TokenKind type;
 };
 
+struct StateBase {
+  virtual ~StateBase() = default;
+  virtual std::unique_ptr<StateBase> clone() const = 0;
+};
+
+struct CustomState : StateBase {
+  std::string value;
+  explicit CustomState(std::string v) : value(std::move(v)) {}
+  std::unique_ptr<StateBase> clone() const override {
+    return std::make_unique<CustomState>(value);
+  }
+};
+
 struct LineData {
-  std::shared_ptr<void> in_state{nullptr};
+  std::unique_ptr<StateBase> out_state;
   std::vector<Token> tokens;
-  std::shared_ptr<void> out_state{nullptr};
+  std::unique_ptr<StateBase> in_state;
 };
 
 #endif