lang/include/basic_nodes.hpp

#pragma once

#include <optional>
#include <string>
#include <utility>
#include <variant>

namespace nodes {

enum class Modifier {
  OUT,       // -> x
  IN,        // <- x
  REF,       // <> x
  OR_FALSE,  // x?
  OR_RETURN, // x!
  NONE,
};

class Node {
public:
  Node(std::pair<size_t, size_t> start_position,
       std::pair<size_t, size_t> end_position)
      : start_position_(start_position), end_position_(end_position) {}

  std::pair<size_t, size_t> get_start_position() { return start_position_; }

  std::pair<size_t, size_t> get_end_position() { return end_position_; }

protected:
  std::pair<size_t, size_t> start_position_;
  std::pair<size_t, size_t> end_position_;
};

struct unit {};
struct null {};

class Literal : public Node {
public:
  template <typename T>
  Literal(Node node, T &&value) : Node(node), value_(std::forward<T>(value)) {}

  template <typename T> std::optional<T *> get() {
    if (std::holds_alternative<T>(value_)) {
      return &std::get<T>(value_);
    }
    return std::nullopt;
  }

  template <typename T> std::optional<const T *> get() const {
    if (std::holds_alternative<T>(value_)) {
      return &std::get<T>(value_);
    }
    return std::nullopt;
  }

  std::variant<double, long long, std::string, char, bool, unit, null> *
  get_any() {
    return &value_;
  }

  const std::variant<double, long long, std::string, char, bool, unit, null> *
  get_any() const {
    return &value_;
  }

private:
  std::variant<double, long long, std::string, char, bool, unit, null> value_;
};

class Identifier : public Node {
public:
  enum IdentifierType {
    SIMPLE_NAME,
    SIMPLE_TYPE,
    TYPECLASS,
    ARGUMENT_NAME,
    ARGUMENT_TYPE,
    // ANNOTATION, used as std::string
    OPERATOR,
    PLACEHOLDER,
  };

  Identifier(Node node, IdentifierType type, std::string &&value)
      : Node(node), type_(type), value_(std::move(value)) {}

  Identifier(Node node, IdentifierType type, const std::string &value)
      : Node(node), type_(type), value_(value) {}

  IdentifierType get_type() { return type_; }

  std::string *get() { return &value_; }

  const std::string *get() const { return &value_; }

private:
  IdentifierType type_;
  std::string value_;
};

} // namespace nodes