feat: introduce help. auto add help through parser generation like another action.

src/headers/parser/argument_parser.hpp

@@ -1,23 +1,72 @@
 #pragma once
-#include <list>
-#include <optional>
-#include <type_traits>
 #ifndef ARGUMENT_PARSER_HPP
 #define ARGUMENT_PARSER_HPP
+
 #include <any>
 #include <atomic>
 #include <base_convention.hpp>
 #include <functional>
 #include <initializer_list>
+#include <list>
 #include <memory>
+#include <optional>
 #include <stdexcept>
 #include <string>
+#include <thread>
 #include <traits.hpp>
+#include <type_traits>
 #include <unordered_map>
 #include <utility>
 #include <vector>
 
+
 namespace argument_parser {
+	namespace internal::atomic {
+		template <typename T> class copyable_atomic {
+		public:
+			copyable_atomic() : value(std::make_shared<std::atomic<T>>()) {}
+			copyable_atomic(T desired) : value(std::make_shared<std::atomic<T>>(desired)) {}
+
+			copyable_atomic(const copyable_atomic &other) : value(other.value) {}
+			copyable_atomic &operator=(const copyable_atomic &other) {
+				if (this != &other) {
+					value = other.value;
+				}
+				return *this;
+			}
+
+			copyable_atomic(copyable_atomic &&other) noexcept = default;
+			copyable_atomic &operator=(copyable_atomic &&other) noexcept = default;
+			~copyable_atomic() = default;
+
+			T operator=(T desired) noexcept {
+				store(desired);
+				return desired;
+			}
+
+			operator T() const noexcept {
+				return load();
+			}
+
+			void store(T desired, std::memory_order order = std::memory_order_seq_cst) noexcept {
+				if (value) {
+					value->store(desired, order);
+				}
+			}
+
+			T load(std::memory_order order = std::memory_order_seq_cst) const noexcept {
+				return value ? value->load(order) : T{};
+			}
+
+			T exchange(T desired, std::memory_order order = std::memory_order_seq_cst) noexcept {
+				return value ? value->exchange(desired, order) : T{};
+			}
+
+		private:
+			std::shared_ptr<std::atomic<T>> value;
+		};
+	} // namespace internal::atomic
+
 	class action_base {
 	public:
 		virtual ~action_base() = default;
@@ -127,6 +176,13 @@ namespace argument_parser {
 		}
 	} // namespace helpers
 
+	/**
+	 * @brief Base class for parsing arguments from the command line.
+	 *
+	 * Note: This class and its methods are NOT thread-safe.
+	 * It must be instantiated and used from a single thread (typically the main thread),
+	 * as operations such as argument processing and checking rely on thread-local or instance-specific state.
+	 */
 	class base_parser {
 	public:
 		template <typename T>
@@ -177,6 +233,18 @@ namespace argument_parser {
 		std::string program_name;
 		std::vector<std::string> parsed_arguments;
 
+		void reset_current_conventions() {
+			_current_conventions = {};
+		}
+
+		void current_conventions(std::initializer_list<conventions::convention const *const> convention_types) {
+			_current_conventions = convention_types;
+		}
+
+		[[nodiscard]] std::initializer_list<conventions::convention const *const> current_conventions() const {
+			return _current_conventions;
+		}
+
 	private:
 		void assert_argument_not_exist(std::string const &short_arg, std::string const &long_arg) const;
 		static void set_argument_status(bool is_required, std::string const &help_text, argument &arg);
@@ -224,6 +292,9 @@ namespace argument_parser {
 		std::unordered_map<std::string, int> long_arguments;
 		std::unordered_map<int, std::string> reverse_long_arguments;
 
+		std::initializer_list<conventions::convention const *const> _current_conventions;
+		internal::atomic::copyable_atomic<std::thread::id> creation_thread_id = std::this_thread::get_id();
+
 		std::list<std::function<void(base_parser const &)>> on_complete_events;
 
 		friend class linux_parser;

src/headers/parser/parser_v2.hpp

@@ -77,9 +77,8 @@ namespace argument_parser::v2 {
 			return base::get_optional<T>(arg);
 		}
 
-		void on_complete(std::function<void(argument_parser::base_parser const &)> const &action) {
-			base::on_complete(action);
-		}
+		using argument_parser::base_parser::display_help;
+		using argument_parser::base_parser::on_complete;
 
 	protected:
 		void set_program_name(std::string p) {
@@ -90,6 +89,9 @@ namespace argument_parser::v2 {
 			return base::parsed_arguments;
 		}
 
+		using argument_parser::base_parser::current_conventions;
+		using argument_parser::base_parser::reset_current_conventions;
+
 	private:
 		template <bool IsTyped, typename ActionType, typename T, typename ArgsMap>
 		void add_argument_impl(ArgsMap const &argument_pairs) {

src/headers/parser/platform_headers/windows_parser.hpp

@@ -13,6 +13,7 @@ namespace argument_parser {
 		class windows_parser : public v2::base_parser {
 		public:
 			windows_parser();
+			using base_parser::display_help;
 		};
 	} // namespace v2
 } // namespace argument_parser

src/source/parser/argument_parser.cpp

@@ -2,6 +2,18 @@
 
 #include <iostream>
 #include <sstream>
+#include <thread>
+
+class deferred_exec {
+public:
+	deferred_exec(std::function<void()> const &func) : func(func) {}
+	~deferred_exec() {
+		func();
+	}
+
+private:
+	std::function<void()> func;
+};
 
 bool contains(std::unordered_map<std::string, int> const &map, std::string const &key) {
 	return map.find(key) != map.end();
@@ -101,6 +113,13 @@ namespace argument_parser {
 	}
 
 	void base_parser::handle_arguments(std::initializer_list<conventions::convention const *const> convention_types) {
+		if (std::this_thread::get_id() != this->creation_thread_id.load()) {
+			throw std::runtime_error("handle_arguments must be called from the main thread");
+		}
+
+		deferred_exec reset_current_conventions([this]() { this->reset_current_conventions(); });
+		this->current_conventions(convention_types);
+
 		for (auto it = parsed_arguments.begin(); it != parsed_arguments.end(); ++it) {
 			std::stringstream error_stream;
 			bool arg_correctly_handled = false;

src/source/parser/platform_parsers/windows_parser.cpp

@@ -1,6 +1,9 @@
+
 #ifdef _WIN32
 
 #include "windows_parser.hpp"
+#include "argument_parser.hpp"
+#include "parser_v2.hpp"
 
 #include <Windows.h>
 #include <iostream>
@@ -96,6 +99,14 @@ namespace argument_parser::v2 {
 	windows_parser::windows_parser() {
 		parse_windows_arguments(ref_parsed_args(),
 								[this](std::string const &program_name) { this->set_program_name(program_name); });
+
+		add_argument({{flags::ShortArgument, "h"},
+					  {flags::LongArgument, "help"},
+					  {flags::Action, helpers::make_non_parametered_action([this]() {
+						   this->display_help(this->current_conventions());
+						   std::exit(0);
+					   })},
+					  {flags::HelpText, "Prints this help text."}});
 	}
 } // namespace argument_parser::v2