PlayerDataEvents.java

package slimeknights.tconstruct.shared;

import net.minecraft.entity.player.EntityPlayer;
import net.minecraft.item.ItemStack;
import net.minecraft.nbt.NBTTagCompound;
import net.minecraftforge.fml.common.eventhandler.SubscribeEvent;
import net.minecraftforge.fml.common.gameevent.PlayerEvent;
import net.minecraftforge.items.ItemHandlerHelper;

import slimeknights.tconstruct.common.config.Config;
import slimeknights.tconstruct.library.Util;
import slimeknights.tconstruct.library.utils.TagUtil;

public class PlayerDataEvents {

  public static final String TAG_PLAYER_HAS_BOOK = Util.prefix("spawned_book");

  @SubscribeEvent
  public void onPlayerLoggedIn(PlayerEvent.PlayerLoggedInEvent event) {
    if(Config.spawnWithBook) {
      NBTTagCompound playerData = event.player.getEntityData();
      NBTTagCompound data = TagUtil.getTagSafe(playerData, EntityPlayer.PERSISTED_NBT_TAG);

      if(!data.getBoolean(TAG_PLAYER_HAS_BOOK)) {
        ItemHandlerHelper.giveItemToPlayer(event.player, new ItemStack(TinkerCommons.book));
        data.setBoolean(TAG_PLAYER_HAS_BOOK, true);
        playerData.setTag(EntityPlayer.PERSISTED_NBT_TAG, data);
      }
    }
  }
}