Added database support for mail

Send mail command now works from console (to use it from console change the uuid in the 'SendMailCommand' file

src/main/java/emu/grasscutter/game/Mail.java

@@ -0,0 +1,99 @@
+package emu.grasscutter.game;
+
+import java.time.Instant;
+import java.util.ArrayList;
+import java.util.List;
+
+public class Mail {
+
+    public int _id;
+    public MailContent mailContent;
+    public List<MailItem> itemList;
+    public long sendTime;
+    public long expireTime;
+    public int importance;
+    public boolean isRead;
+    public boolean isAttachmentGot;
+    public int stateValue;
+
+    public Mail() {
+        _id = 1;
+        mailContent = new MailContent("No title set...", "No content set...");
+        itemList = new ArrayList<>();
+        sendTime = 0;
+        expireTime = 0;
+        importance = 1;
+        isRead = true;
+        isAttachmentGot = true;
+        stateValue = 1;
+    }
+
+    public Mail(MailContent mailContent, List<MailItem> itemList, long expireTime) {
+        this(mailContent, itemList, expireTime, 1);
+    }
+
+    public Mail(MailContent mailContent, List<MailItem> itemList, long expireTime, int importance) {
+        this(mailContent, itemList, expireTime, importance, 1);
+    }
+
+    public Mail(MailContent mailContent, List<MailItem> itemList, long expireTime, int importance, int state) {
+        this(0, mailContent, itemList, expireTime, importance, state);
+    }
+
+    public Mail(int _id, MailContent mailContent, List<MailItem> itemList, long expireTime, int importance, int state) {
+        this._id = _id;
+        this.mailContent = mailContent;
+        this.itemList = itemList;
+        this.sendTime = (int) Instant.now().EPOCH.getEpochSecond();
+        this.expireTime = expireTime;
+        this.importance = importance;
+        this.isRead = false;
+        this.isAttachmentGot = false;
+        this.stateValue = state;
+    }
+
+    public static class MailContent {
+        public String title;
+        public String content;
+        public String sender;
+
+        public MailContent() {
+            this.title = "";
+            this.content = "loading...";
+            this.sender = "loading";
+        }
+
+        public MailContent(String title, String content) {
+            this(title, content, "Server");
+        }
+
+        public MailContent(String title, String content, GenshinPlayer sender) {
+            this(title, content, sender.getNickname());
+        }
+
+        public MailContent(String title, String content, String sender) {
+            this.title = title;
+            this.content = content;
+            this.sender = sender;
+        }
+    }
+
+    public static class MailItem {
+        public int itemId;
+        public int itemCount;
+
+        public MailItem() {
+            this.itemId = 11101;
+            this.itemCount = 1;
+        }
+
+        public MailItem(int itemId) {
+            this(itemId, 1);
+        }
+
+        public MailItem(int itemId, int itemCount) {
+            this.itemId = itemId;
+            this.itemCount = itemCount;
+        }
+    }
+}