Profile set birthday feature

src/main/java/emu/grasscutter/game/player/PlayerBirthday.java

@@ -0,0 +1,68 @@
+package emu.grasscutter.game.player;
+
+import emu.grasscutter.net.proto.BirthdayOuterClass.Birthday;
+
+public class PlayerBirthday {
+    private int day;
+    private int month;
+
+    public PlayerBirthday(){
+        this.day = 0;
+        this.month = 0;
+    }
+
+    public PlayerBirthday(int day, int month){
+        this.day = day;
+        this.month = month;
+    }
+
+    public PlayerBirthday set(PlayerBirthday birth){
+        this.day = birth.day;
+        this.month = birth.month;
+
+        return this;
+    }
+
+    public PlayerBirthday set(int d, int m){
+        this.day = d;
+        this.month = m;
+
+        return this;
+    }
+
+    public PlayerBirthday setDay(int value){
+        this.day = value;
+        return this;
+    }
+
+    public PlayerBirthday setMonth(int value){
+        this.month = value;
+        return this;
+    }
+
+    public int getDay(){
+        return this.day;
+    }
+
+    public int getMonth(){
+        return this.month;
+    }
+
+    public Birthday toProto(){
+        return Birthday.newBuilder()
+                .setDay(this.getDay())
+                .setMonth(this.getMonth())
+                .build();
+    }
+
+    public Birthday.Builder getFilledProtoWhenNotEmpty(){
+        if(this.getDay() > 0)
+        {
+            return Birthday.newBuilder()
+                    .setDay(this.getDay())
+                    .setMonth(this.getMonth());
+        }
+
+        return Birthday.newBuilder();
+    }
+}