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

#ifndef	LFJAIL_COMMAND_MAP_HH
#define	LFJAIL_COMMAND_MAP_HH

/*
 * command_map represents a hierarchical list of commands.  At each level,
 * a command is mapped to a handler, which can either be a function, in
 * which case we execute the function, or another command_map, in which
 * case we invoke the new map
 */

#include <functional>
#include <iostream>
#include <string>
#include <utility>

#include "context.hh"
#include "string_utils.hh"
#include "usage_error.hh"

namespace lfjail::command {

namespace detail {

struct command_base {
	command_base(command_base const &) = delete;
	command_base &operator=(command_base const &) = delete;

	command_base(std::string_view path) noexcept;
	virtual auto invoke(context const &, int, char **) -> int = 0;
};

} // namespace detail

// Declare a global command and add it to the root node.
template<std::invocable<context const &, int, char **> F>
struct command final : detail::command_base {
	command(std::string_view path, F fn)
	try : command_base(path)
	    , _func(std::move(fn))
	{
	} catch (std::exception const &exc) {
		std::cerr << "lfjail: ERROR: failed to initialise command "
			<< path << ": " << exc.what() << "\n";
		std::abort();
	}

	auto invoke(context const &ctx, int argc, char **argv) -> int override {
		return std::invoke(_func, ctx, argc, argv);
	}

private:
	F _func;
};

// Dispatch a command based on argc/argv.
auto dispatch(context const &, int argc, char **argv) -> int;

// Print a list of commands to stderr.
void print_usage(std::string_view prefix);

} // namespace lfjail

#endif	// !LFJAIL_COMMAND_MAP_HH