#pragma once
#include "common.h"

namespace antlrSysY {
template <typename T_V> class ScopeTable {

  typedef std::map<std::string, T_V> ScopeTableEntry_t;

private:
  std::vector<ScopeTableEntry_t> _scope_list;

public:
  // On init, there is already an empty scope
  ScopeTable() {
    _scope_list.push_back(ScopeTableEntry_t());
  }
  ~ScopeTable() {}

  void enter_scope() {
    _scope_list.push_back(ScopeTableEntry_t());
  };

  void leave_scope() {
    if (_scope_list.size() <= 1)
      throw GrammarException("Unable to leave global scope");
    _scope_list.pop_back();
  };

  void push_name(const std::string &name, const T_V &value) {
    auto &current_scope = _scope_list.back();

    if (current_scope.count(name))
      throw GrammarException("Duplicate name in current scope");
    current_scope[name] = value;
  };

  std::optional<T_V> get_name(const std::string &name) {
    for (auto i = _scope_list.size() - 1; i >= 0; --i) {
      if (_scope_list[i].count(name)) {
        return {_scope_list[i][name]};
      }
    }
    return {};
  };

  std::optional<T_V> get_name(const std::string &name, int level) {
    if (_scope_list[level].count(name)) {
      return {_scope_list[level][name]};
    }
    return {};
  };
  int get_level() const {
    return _scope_list.size() - 1;
  }
};
}