Add history support, and fix parsing system.

include/internal/syntax/parser.h

@@ -1,57 +1,54 @@
 #pragma once
 
 #include "decl.h"
-#include "internal/vase/vase.h"
 #include "pch.h"
 
 namespace bed::internal::syntax {
-struct Parser {
-  static constexpr uint64_t MAX_CHUNK = 512;
+struct ParserSnapshot {
+  ParseState *root = nullptr;
+  Language *lang = nullptr;
+};
 
-  ParseState *root;
-  Language lang;
-  bool in_edit = false;
+ParserSnapshot make_parser(vase::Shard *vase, uint64_t lines, Language *lang);
+ParserSnapshot retain(const ParserSnapshot &snap);
+void release(ParserSnapshot &snap);
+
+uint64_t next_closing(const ParserSnapshot &snap, uint64_t line);
+uint64_t prev_opening(const ParserSnapshot &snap, uint64_t line);
+
+struct Iterator {
+  ParserSnapshot snap;
+  std::optional<vase::Iterator> it;
+  void *state;
+  uint64_t at;
+  std::vector<Token> tokens;
+  std::vector<ParseEvent> events;
+  Iterator(uint64_t, ParserSnapshot, vase::Shard *);
+  ~Iterator();
+  Iterator(const Iterator &) = delete;
+  Iterator &operator=(const Iterator &) = delete;
+  Iterator(Iterator &&other);
+  Iterator &operator=(Iterator &&other);
+  void next();
+};
+
+std::optional<Iterator> get_hl(const ParserSnapshot &snap, vase::Shard *vase, uint64_t target);
+
+void insert(ParserSnapshot &snap, vase::Shard *vase, uint64_t start, uint64_t count);
+void erase(ParserSnapshot &snap, vase::Shard *vase, uint64_t start, uint64_t count);
+
+struct Edit {
+  ParserSnapshot *target;
   bool dirty = false;
   uint64_t dirty_start = 0;
   uint64_t dirty_end = 0;
+  int64_t edit_delta = 0;
 
-  Parser(vase::Shard *, uint64_t, Language);
-  ~Parser();
-  Parser(const Parser &) = delete;
-  Parser &operator=(const Parser &) = delete;
+  explicit Edit(ParserSnapshot &snap) : target(&snap) {}
 
-  void reset(vase::Shard *, uint64_t, Language);
-  void erase(vase::Shard *, uint64_t, uint64_t);
-  void insert(vase::Shard *, uint64_t, uint64_t);
-  void modify(vase::Shard *, uint64_t, uint64_t);
-
-  void begin_edit();
-  void erase(uint64_t start, uint64_t count);
-  void insert(uint64_t start, uint64_t count);
-  void end_edit(vase::Shard *vase);
   void mark_dirty(uint64_t start, uint64_t end);
-
-  uint64_t next_closing(uint64_t line);
-  uint64_t prev_opening(uint64_t line);
-
-  std::pair<ParseState *, ParseState *> split_tree(ParseState *node, uint64_t line);
-  ParseState *join_tree(ParseState *a, ParseState *b);
-
-  struct Iterator {
-    Parser *p;
-    std::optional<vase::Iterator> it;
-    void *state;
-    uint64_t at;
-    std::vector<Token> tokens;
-    std::vector<ParseEvent> events;
-    Iterator(uint64_t, Parser *, vase::Shard *);
-    ~Iterator();
-    Iterator(const Iterator &) = delete;
-    Iterator &operator=(const Iterator &) = delete;
-    Iterator(Iterator &&other);
-    Iterator &operator=(Iterator &&other);
-    void next();
-  };
-  std::optional<Iterator> get_hl(vase::Shard *, uint64_t);
+  void insert(uint64_t start, uint64_t count);
+  void erase(uint64_t start, uint64_t count);
+  void commit(vase::Shard *vase);
 };
 } // namespace bed::internal::syntax