/*
 * This source code is released into the public domain.
 */

#ifndef	LFJAIL_ARGV_HH
#define	LFJAIL_ARGV_HH

#include <memory>
#include <ranges>
#include <string>
#include <vector>

namespace lfjail {

/*
 * argv: stores a null-terminated array of nul-terminated C strings.
 * argv::data() is suitable for passing to ::execv().
 *
 * Create an argv using argv::from_range(), which takes a range of
 * string-like objects.
 */

struct argv {
	/*
	 * Create a new argv from a range.
	 */
	static auto from_range(std::ranges::range auto &&args) -> argv {
		auto ret = argv{};

		for (auto &&arg : args)
			ret._add_arg(std::string_view(arg));

		ret._args.push_back(nullptr);
		return ret;
	}

	template<typename T>
	static auto from_args(std::initializer_list<T> &&args) {
		return from_range(std::move(args));
	}

	argv(argv &&) noexcept = default;
	auto operator=(this argv &, argv &&other) -> argv& = default;

	// Not copyable.  TODO: for completeness, it probably should be.
	argv(argv const &) = delete;
	auto operator=(this argv &, argv const &other) -> argv& = delete;

	~argv();

	// Access the stored arguments.
	auto data(this argv const &self) -> char const * const * {
		return self._args.data();
	}

	auto data(this argv &self) -> char * const * {
		return self._args.data();
	}

	auto size(this argv const &self) {
		return self._args.size();
	}

	// Range access
	auto begin(this argv const &self) {
		return self._args.begin();
	}

	auto end(this argv const &self) {
		return self._args.end();
	}

private:
	// Use the from_range() factory method to create new instances.
	argv() = default;

	// The argument pointers, including the null terminator.
	std::vector<char *> _args;

	// Add a new argument to the array.
	auto _add_arg(this argv &self, std::string_view arg) -> void;
};

} // namespace lf

#endif	// !LFJAIL_ARGV_HH