Grasscutter/src/main/java/emu/grasscutter/server/packet/send/PacketGetMailItemRsp.java

package emu.grasscutter.server.packet.send;

import emu.grasscutter.data.GameData;
import emu.grasscutter.game.inventory.GameItem;
import emu.grasscutter.game.mail.Mail;
import emu.grasscutter.game.player.Player;
import emu.grasscutter.game.props.ActionReason;
import emu.grasscutter.net.packet.BasePacket;
import emu.grasscutter.net.packet.PacketOpcodes;
import emu.grasscutter.net.proto.EquipParamOuterClass;
import emu.grasscutter.net.proto.GetMailItemRspOuterClass.GetMailItemRsp;

import java.util.ArrayList;
import java.util.List;
import java.util.stream.Collectors;

public class PacketGetMailItemRsp  extends BasePacket {

    public PacketGetMailItemRsp(Player player, List<Integer> mailList) {
        super(PacketOpcodes.GetMailItemRsp);

        List<Mail> claimedMessages = new ArrayList<>();
        List<EquipParamOuterClass.EquipParam> claimedItems = new ArrayList<>();

        GetMailItemRsp.Builder proto = GetMailItemRsp.newBuilder();

        for (int mailId : mailList) {
            Mail message = player.getMail(mailId);

            for(Mail.MailItem mailItem : message.itemList) {
                EquipParamOuterClass.EquipParam.Builder item = EquipParamOuterClass.EquipParam.newBuilder();
                int promoteLevel = 0;
                if (mailItem.itemLevel > 20) { // 20/40
                    promoteLevel = 1;
                } else if (mailItem.itemLevel > 40) { // 40/50
                    promoteLevel = 2;
                } else if (mailItem.itemLevel > 50) { // 50/60
                    promoteLevel = 3;
                } else if (mailItem.itemLevel > 60) { // 60/70
                    promoteLevel = 4;
                } else if (mailItem.itemLevel > 70) { // 70/80
                    promoteLevel = 5;
                } else if (mailItem.itemLevel > 80) { // 80/90
                    promoteLevel = 6;
                }

                item.setItemId(mailItem.itemId);
                item.setItemNum(mailItem.itemCount);
                item.setItemLevel(mailItem.itemLevel);
                item.setPromoteLevel(promoteLevel);
                claimedItems.add(item.build());

                GameItem gameItem = new GameItem(GameData.getItemDataMap().get(mailItem.itemId));
                gameItem.setCount(mailItem.itemCount);
                gameItem.setLevel(mailItem.itemLevel);
                gameItem.setPromoteLevel(promoteLevel);
                player.getInventory().addItem(gameItem, ActionReason.MailAttachment);
            }

            message.isAttachmentGot = true;
            claimedMessages.add(message);

            player.replaceMailByIndex(mailId, message);
        }

        proto.addAllMailIdList(claimedMessages.stream().map(message -> player.getMailId(message)).collect(Collectors.toList()));
        proto.addAllItemList(claimedItems);

        this.setData(proto.build());
        player.getSession().send(new PacketMailChangeNotify(player, claimedMessages)); // For some reason you have to also send the MailChangeNotify packet
    }
}