name = "help";

group = "void";

shortDescription = "Print list of commands";

longDescription = "";

argumentTypes = [ "command-or-group-name" ];

function execute() {

    if (arguments.length == 0) {

        var groups = getCommandGroups();

        message("List of command categories:");

        message("");

        for (var name in groups) {

            if (name == "void")

                continue;

            var data = groups[name];

            message(name + " :: " + data.shortDescription);

        }

        message("");

        message("Type \"help\" followed by a category name for a list of commands in that category.");

        message("Type \"help all\" for the list of all commands.");

        message("Type \"help\" followed by a command name for full documentation.");

        message("Command name abbreviations are allowed if they are unambiguous.");

    } else {

        var arg = arguments[0];

        if (arg == "all") {

            var groups = getCommandGroups();

            for (var name in groups) {

                if (name == "void")

                    continue;

                message("Command category: " + name);

                message("");

                var commands = getCommandsInGroup(name);

                for (var i = 0; i < commands.length; ++i) {

                    var data = commands[i];

                    message(data.name + " :: " + data.shortDescription);

                }

                message("");

            }

        } else {

            var data = findCommand(arg);

            if (data != undefined) {

                message(data.shortDescription + ".");

                if (data.longDescription.length != 0)

                    message(data.longDescription);

                if (data.aliases.length != 0)

                    message("Aliases: " + data.aliases.join(", "));

                if (data.seeAlso.length != 0)

                    message("See also: " + data.seeAlso.join(", "));

            } else {

                data = getCommandGroups()[arg];

                if (data != undefined) {

                    message(data.shortDescription + ".");

                    message("");

                    message("List of commands:");

                    message("");

                    var commands = getCommandsInGroup(arg);

                    for (var i = 0; i < commands.length; ++i) {

                        var data = commands[i];

                        message(data.name + " :: " + data.shortDescription);

                    }

                } else {

                    message("Undefined command \"" + arg + "\". Try \"help\".");

                }

            }

        }

    }

};