BauSystem/BauSystem_Main/src/de/steamwar/bausystem/commands/CommandTraceTabCompleter.java

package de.steamwar.bausystem.commands;

import de.steamwar.bausystem.tracer.TNTTracer15;
import de.steamwar.core.Core;
import org.bukkit.command.Command;
import org.bukkit.command.CommandSender;
import org.bukkit.command.TabCompleter;
import org.bukkit.entity.Player;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;

public class CommandTraceTabCompleter implements TabCompleter {

    @Override
    public List<String> onTabComplete(CommandSender sender, Command command, String label, String[] args) {
        if(!(sender instanceof Player)) return new ArrayList<>();
        Player player = (Player) sender;

        switch (Core.getVersion()) {
            case 15:
                return tracer15TabComplete(player, args);
            default:
                return tracer12TabComplete(player, args);
        }
    }

    private List<String> tracer12TabComplete(Player player, String[] args) {
        List<String> tabComplete = new ArrayList<>();
        tabComplete.add("start");
        tabComplete.add("show");
        tabComplete.add("stop");

        return manageList(tabComplete, args, 0);
    }

    private List<String> tracer15TabComplete(Player player, String[] args) {
        List<String> tabComplete = new ArrayList<>();
        if (TNTTracer15.getStatus() == TNTTracer15.Status.IDLE || TNTTracer15.getStatus() == TNTTracer15.Status.IDLE_AUTO) {
            tabComplete.add("start");
        } else {
            tabComplete.add("stop");
        }
        tabComplete.add("toggleauto");
        tabComplete.add("togglewater");
        tabComplete.add("show");
        if (args[0].equalsIgnoreCase("show") && args.length == 2) {
            return manageList(new ArrayList<>(Arrays.asList("block", "particle")), args, 1);
        }
        tabComplete.add("hide");
        tabComplete.add("delete");
        tabComplete.add("interpolate");
        if (args[0].equalsIgnoreCase("interpolate") && args.length == 2) {
            return manageList(new ArrayList<>(Arrays.asList("all", "yaxis", "none")), args, 1);
        }
        //tabComplete.add("gui");
        tabComplete.add("list");

        if (args.length == 2) {
            return new ArrayList<>();
        }
        return manageList(tabComplete, args, 0);
    }

    private List<String> manageList(List<String> strings, String[] args, int index) {
        for (int i = strings.size() - 1; i >= 0; i--) {
            if (!strings.get(i).startsWith(args[index])) {
                strings.remove(i);
            }
        }
        return strings;
    }

}