// 符号表：记录局部变量/常量/参数定义。
#pragma once

#include <optional>
#include <string>
#include <unordered_map>
#include <vector>

 #include "SysYParser.h"

enum class BaseTypeKind { Int, Float, Void };

struct TypeDesc {
  BaseTypeKind base = BaseTypeKind::Int;
  std::vector<int> dims;  // 为空表示标量；数组维度允许首维为 -1 表示形参不定长
  bool is_const = false;
};

enum class SymbolKind { Var, Const, Param };

struct SymbolEntry {
  SymbolKind kind = SymbolKind::Var;
  SysYParser::VarDefContext* var_decl = nullptr;
  SysYParser::ConstDefContext* const_decl = nullptr;
  SysYParser::FuncFParamContext* param_decl = nullptr;
  TypeDesc type;  // 记录类型信息
  bool is_const = false;
  std::optional<int> const_value;
};

class SymbolTable {
 public:
  void EnterScope();
  void ExitScope();

  bool ContainsInCurrentScope(const std::string& name) const;
  void Add(const std::string& name, const SymbolEntry& entry);
  const SymbolEntry* Lookup(const std::string& name) const;

 private:
  std::vector<std::unordered_map<std::string, SymbolEntry>> scopes_;
};