cl3/include/utils/command_parser.hpp

#pragma once

#include <iostream>
#include <optional>
#include <vector>
#include <string>
#include <functional>
#include <variant>

enum class PatternType { FixedWord, AnyWord, AnyWords };

struct Pattern {
  PatternType type;
  std::string fixed_word;
};

using Callback = std::variant<std::function<void(const std::vector<std::string>&)>,
                              std::function<bool(const std::vector<std::string>&)>>;

class Parser {
 public:
  void AddRule(const std::vector<Pattern>& pattern, const auto& callback,
               bool find_in_suggestion = true) {
    if constexpr (std::is_same_v<
                      decltype(callback(std::declval<const std::vector<std::string>&>())), void>) {
      AddRuleImpl(pattern, std::function<void(const std::vector<std::string>&)>(callback),
                  find_in_suggestion);
    } else {
      AddRuleImpl(pattern, std::function<bool(const std::vector<std::string>&)>(callback),
                  find_in_suggestion);
    }
  }
  void Parse(int argc, char* argv[]) const;
  std::vector<std::string> GetPossibleAdditions(int argc, char* argv[]) const;
  std::vector<std::string> GetPossibleAdditions(const std::vector<std::string>&) const;

 private:
  void AddRuleImpl(const std::vector<Pattern>& pattern, const Callback& callback,
                   bool find_in_suggestion);
  bool Match(const std::vector<Pattern>& pattern, const std::vector<std::string>& args) const;

 private:
  struct Rule {
    Rule(const std::vector<Pattern>& pattern, Callback callback, bool find_in_suggestion)
        : pattern(pattern), callback(callback), find_in_suggestion(find_in_suggestion) {}
    std::vector<Pattern> pattern;
    Callback callback;
    bool find_in_suggestion;
  };

  std::vector<Rule> rules_;
};

std::vector<Pattern> MakePattern(
    std::initializer_list<std::variant<const char*, PatternType>> elements);