hek/src/main/java/me/hammerle/HeK.java

package me.hammerle;

import java.util.Arrays;
import net.minecraft.block.Block;
import net.minecraft.block.Blocks;
import net.minecraft.client.Minecraft;
import net.minecraft.util.text.ChatType;
import net.minecraft.util.text.StringTextComponent;
import net.minecraftforge.client.event.ClientChatEvent;
import net.minecraftforge.client.event.ClientChatReceivedEvent;
import net.minecraftforge.eventbus.api.SubscribeEvent;
import net.minecraftforge.fml.common.Mod;

@Mod.EventBusSubscriber
@Mod("hefix")
public class HeK {

    private static String filter = "Hegemony";
    private static String percent = null;
    private static double startExp = 0.0;
    private static double exp = 0.0;
    private static double nextExp = 0.0;

    private static void sendMessage(String msg) {
        Minecraft.getInstance().ingameGUI.addChatMessage(ChatType.CHAT, new StringTextComponent(msg));
    }

    private static boolean isOre(Block b) {
        return b == Blocks.IRON_ORE || b == Blocks.COAL_ORE;
    }

    @SubscribeEvent
    public static void onClientChat(ClientChatEvent e) {
        if(!e.getMessage().startsWith("/")) {
            return;
        }
        String[] parts = e.getMessage().split(" ");
        switch(parts[0]) {
            case "/hefix":
                e.setCanceled(true);
                if(parts.length < 2) {
                    filter = null;
                    sendMessage("Filter cleared");
                    return;
                }
                filter = String.join(" ", Arrays.copyOfRange(parts, 1, parts.length));
                sendMessage("Filter set to '" + filter + "'");
                break;
            case "/percent":
                e.setCanceled(true);
                if(parts.length < 4) {
                    percent = null;
                    sendMessage("EXP cleared");
                    return;
                }
                percent = parts[1];
                try {
                    exp = Double.parseDouble(parts[2]);
                    startExp = exp;
                    nextExp = Double.parseDouble(parts[3]);
                } catch(NumberFormatException ex) {
                    sendMessage("Type valid numbers");
                    return;
                }
                sendMessage(String.format("Percent set to '%s' and %.1f and %.1f", percent, exp, nextExp));
                break;
        }

    }

    @SubscribeEvent
    public static void onChatReceive(ClientChatReceivedEvent e) {
        String msg = e.getMessage().getFormattedText();
        if(filter != null && msg.contains(filter)) {
            e.setCanceled(true);
        }
        if(percent != null && e.getType() == ChatType.GAME_INFO && msg.contains(percent)) {
            msg = msg.replaceAll("§.", "");
            String[] parts = msg.split(" ");
            for(int i = 0; i < parts.length; i++) {
                if(parts[i].equals(percent)) {
                    if(i == 0) {
                        continue;
                    }
                    try {
                        exp += Double.parseDouble(parts[i - 1]);
                        double d = ((exp - startExp) * 100.0) / (nextExp - startExp);
                        e.setMessage(new StringTextComponent(String.format("§6%s§r +%s - %.1f%%", percent, parts[i - 1], d)));
                        return;
                    } catch(NumberFormatException ex) {
                        e.setMessage(new StringTextComponent(ex.getLocalizedMessage()));
                        break;
                    }
                }
            }
            e.setCanceled(true);
        }
    }
}