feature(serenitea pot): Implementation of the entry function

It's being perfected, so don't worry. (probably)

src/main/java/emu/grasscutter/server/packet/recv/HandlerWidgetDoBagReq.java

+package emu.grasscutter.server.packet.recv;
+
+import emu.grasscutter.Grasscutter;
+import emu.grasscutter.data.GameData;
+import emu.grasscutter.data.def.GadgetData;
+import emu.grasscutter.game.entity.EntityVehicle;
+import emu.grasscutter.game.entity.GameEntity;
+import emu.grasscutter.game.props.LifeState;
+import emu.grasscutter.net.packet.Opcodes;
+import emu.grasscutter.net.packet.PacketHandler;
+import emu.grasscutter.net.packet.PacketOpcodes;
+import emu.grasscutter.net.proto.*;
+import emu.grasscutter.server.game.GameSession;
+import emu.grasscutter.server.packet.send.PacketSceneEntityAppearNotify;
+import emu.grasscutter.server.packet.send.PacketWidgetCoolDownNotify;
+import emu.grasscutter.server.packet.send.PacketWidgetDoBagRsp;
+import emu.grasscutter.server.packet.send.PacketWidgetGadgetDataNotify;
+import emu.grasscutter.utils.Position;
+
+import java.util.List;
+
+@Opcodes(PacketOpcodes.WidgetDoBagReq)
+public class HandlerWidgetDoBagReq extends PacketHandler {
+
+    @Override
+    public void handle(GameSession session, byte[] header, byte[] payload) throws Exception {
+        WidgetDoBagReqOuterClass.WidgetDoBagReq req = WidgetDoBagReqOuterClass.WidgetDoBagReq.parseFrom(payload);
+        switch (req.getMaterialId()) {
+            case 220026 -> {
+                GadgetData gadgetData = GameData.getGadgetDataMap().get(70500025);
+                Position pos = new Position(req.getWidgetCreatorInfo().getLocationInfo().getPos());
+                Position rot = new Position(req.getWidgetCreatorInfo().getLocationInfo().getRot());
+                GameEntity entity = new EntityVehicle(
+                        session.getPlayer().getScene(),
+                        session.getPlayer(),
+                        gadgetData.getId(),
+                        0,
+                        pos,
+                        rot
+                );
+
+                session.getPlayer().getScene().addEntity(entity);
+
+                session.send(new PacketWidgetGadgetDataNotify(70500025, List.of(entity.getId())));  // ???
+                session.send(new PacketWidgetCoolDownNotify(15, System.currentTimeMillis() + 5000L, true));
+                session.send(new PacketWidgetCoolDownNotify(15, System.currentTimeMillis() + 5000L, true));
+                // Send twice, and I don't know why, Ask mhy
+                session.send(new PacketWidgetDoBagRsp());
+            }
+            default -> {
+                session.send(new PacketWidgetDoBagRsp());
+            }
+
+        }
+    }
+
+}

src/main/java/emu/grasscutter/server/packet/send/PacketWidgetCoolDownNotify.java

+package emu.grasscutter.server.packet.send;
+
+import emu.grasscutter.net.packet.BasePacket;
+import emu.grasscutter.net.packet.PacketOpcodes;
+import emu.grasscutter.net.proto.WidgetCoolDownDataOuterClass;
+import emu.grasscutter.net.proto.WidgetCoolDownNotifyOuterClass;
+
+public class PacketWidgetCoolDownNotify extends BasePacket {
+
+    public PacketWidgetCoolDownNotify(int id, long coolDownTime, boolean isSuccess) {
+        super(PacketOpcodes.WidgetCoolDownNotify);
+
+        WidgetCoolDownNotifyOuterClass.WidgetCoolDownNotify proto = WidgetCoolDownNotifyOuterClass.WidgetCoolDownNotify.newBuilder()
+                .addGroupCoolDownDataList(
+                        WidgetCoolDownDataOuterClass.WidgetCoolDownData.newBuilder()
+                                .setId(id)
+                                .setCoolDownTime(coolDownTime)
+                                .setIsSuccess(isSuccess)
+                                .build()
+                )
+                .build();
+
+        this.setData(proto);
+    }
+}

src/main/java/emu/grasscutter/server/packet/send/PacketWidgetDoBagRsp.java

+package emu.grasscutter.server.packet.send;
+
+import emu.grasscutter.net.packet.BasePacket;
+import emu.grasscutter.net.packet.PacketOpcodes;
+import emu.grasscutter.net.proto.WidgetDoBagRspOuterClass;
+
+public class PacketWidgetDoBagRsp extends BasePacket {
+
+    public PacketWidgetDoBagRsp(int materialId) {
+        super(PacketOpcodes.WidgetDoBagRsp);
+
+        WidgetDoBagRspOuterClass.WidgetDoBagRsp proto = WidgetDoBagRspOuterClass.WidgetDoBagRsp.newBuilder()
+                .setMaterialId(materialId)
+                .setRetcode(0)
+                .build();
+
+        this.setData(proto);
+    }
+
+    public PacketWidgetDoBagRsp() {
+        super(PacketOpcodes.WidgetDoBagRsp);
+
+        WidgetDoBagRspOuterClass.WidgetDoBagRsp proto = WidgetDoBagRspOuterClass.WidgetDoBagRsp.newBuilder()
+                .build();
+
+        this.setData(proto);
+    }
+}

src/main/java/emu/grasscutter/server/packet/send/PacketWidgetGadgetDataNotify.java

+package emu.grasscutter.server.packet.send;
+
+import emu.grasscutter.net.packet.BasePacket;
+import emu.grasscutter.net.packet.PacketOpcodes;
+import emu.grasscutter.net.proto.WidgetGadgetDataNotifyOuterClass;
+import emu.grasscutter.net.proto.WidgetGadgetDataOuterClass;
+
+import java.io.IOException;
+import java.util.List;
+
+public class PacketWidgetGadgetDataNotify extends BasePacket {
+    public PacketWidgetGadgetDataNotify(int gadgetId, List<Integer> gadgetEntityIdList) throws IOException {
+        super(PacketOpcodes.WidgetGadgetDataNotify);
+
+        WidgetGadgetDataNotifyOuterClass.WidgetGadgetDataNotify proto = WidgetGadgetDataNotifyOuterClass.WidgetGadgetDataNotify.newBuilder()
+                .setWidgetGadgetData(
+                        WidgetGadgetDataOuterClass.WidgetGadgetData.newBuilder()
+                                .setGadgetId(gadgetId)
+                                .addAllGadgetEntityIdList(gadgetEntityIdList)
+                                .build()
+                )
+                .build();
+
+        this.setData(proto);
+    }
+}