public class OrenCommandHandler implements CommandExecutor {

    /**
     * All the commands registered and past on
     */
    private ArrayList<OrenCommand> commands = new ArrayList<>();

    @Override
    public boolean onCommand(CommandSender sender, Command cmd, String label, String[] args) {
        if (args.length == 0) {
            sender.sendMessage("§8§lOrenMC Commands:");
            sender.sendMessage(help(0));
        } else if (NumberUtils.isNumber(args[0])) {
            sender.sendMessage("§8§lOrenMC Commands:");
            sender.sendMessage(help(Integer.parseInt(args[0])));
        } else {
            OrenCommand oc = getCommand(args[0]);
            if (oc == null) {
                sender.sendMessage("§8§lOrenMC Commands:" + help(0));
                sender.sendMessage(help(0));
            } else {
                oc.getExecutor().onCommand(sender, cmd, args[0], args.length >= 2 ? Arrays.copyOfRange(args, 1, args.length) : new String[0]);
            }
        }
        return true;
    }

    /**
     * Get a string of all the commands registered
     *
     * @return The commands separated by a comma
     */
    private String help(int start) {
        StringBuilder sb = new StringBuilder();

        OrenCommand oc;
        for (int i = start * 9; i < commands.size() && i < (start + 1) * 9; i++) {
            oc = commands.get(i);
            sb.append("§a" + StringUtils.capitalize(oc.getName()) + ": §7" + oc.getDescription() + "\n");
        }
        return sb.toString().trim();
    }

    /**
     * Add a command to be handled by OrenCore.
     *
     * @param name
     *            The name of the command
     * @param executor
     *            The executor to handle the command
     * @param aliases
     *            Any aliases of the command
     */
    public void hookCommand(String name, CommandExecutor executor, String description, String... aliases) {
        commands.add(new OrenCommand(name, executor, description, aliases));
    }

    /**
     * Get the command based on the given alias or label
     *
     * @param label
     *            The alias or label
     * @return the corresponding command
     */
    private OrenCommand getCommand(String label) {
        for (OrenCommand oc : commands) {
            if (oc.isAlias(label)) {
                return oc;
            }
        }
        return null;
    }

    private class OrenCommand {

        private String name;
        private CommandExecutor executor;
        private String description;
        private String[] aliases;

        public OrenCommand(String name, CommandExecutor executor, String description, String... aliases) {
            this.name = name;
            this.executor = executor;
            this.description = description;
            this.aliases = aliases;
        }

        public CommandExecutor getExecutor() {
            return executor;
        }

        public String getName() {
            return name;
        }

        public String getDescription() {
            return description;
        }

        public boolean isAlias(String label) {
            if (label.equalsIgnoreCase(name)) {
                return true;
            }
            for (String alias : aliases) {
                if (alias.equalsIgnoreCase(label)) {
                    return true;
                }
            }
            return false;
        }

    }
}