Added Traveler's birthday gift system

src/main/java/emu/grasscutter/game/mail/BirthdayMailSystem.java

@@ -0,0 +1,137 @@
+package emu.grasscutter.game.mail;
+
+import emu.grasscutter.Grasscutter;
+import emu.grasscutter.game.player.Player;
+import emu.grasscutter.game.props.ActionReason;
+
+import java.time.LocalDate;
+import java.time.ZoneId;
+import java.util.ArrayList;
+import java.util.List;
+
+/**
+ * System for handling birthday gifts for players.
+ * Checks if today is a player's birthday and sends a gift if it is.
+ */
+public class BirthdayMailSystem {
+    // Mail content constants
+    private static final String MAIL_TITLE = "Best Wishes on Your Birthday";
+    private static final String MAIL_CONTENT = "Happy Birthday, Traveler! Please find your gift attached to this message. Thank you for all your support. We wish you a brighter future, no matter what you are going through.";
+    private static final String MAIL_SENDER = "Server";
+
+    // Gift item ID - Cake for Traveler
+    private static final int BIRTHDAY_GIFT_ID = 118008;
+    private static final int BIRTHDAY_GIFT_COUNT = 1;
+
+    /**
+     * Checks if today is the player's birthday and sends a gift if it is.
+     * Should be called when a player logs in.
+     *
+     * @param player The player to check
+     */
+    public static void checkBirthdayAndSendGift(Player player) {
+        if (player == null || !player.hasBirthday()) {
+            return;
+        }
+
+        // Get current date
+        LocalDate currentDate = LocalDate.now(ZoneId.systemDefault());
+        int currentDay = currentDate.getDayOfMonth();
+        int currentMonth = currentDate.getMonthValue();
+
+        // Get player's birthday
+        int birthdayDay = player.getBirthday().getDay();
+        int birthdayMonth = player.getBirthday().getMonth();
+
+        // Check if today is the player's birthday
+        if (currentDay == birthdayDay && currentMonth == birthdayMonth) {
+            // Check if player already received birthday gift today
+            if (!hasReceivedBirthdayGiftToday(player)) {
+                sendBirthdayGift(player);
+            }
+        }
+    }
+
+    /**
+     * Sends a birthday gift to the player.
+     *
+     * @param player The player to send the gift to
+     */
+    private static void sendBirthdayGift(Player player) {
+        // Create mail content
+        Mail.MailContent mailContent = new Mail.MailContent(MAIL_TITLE, MAIL_CONTENT, MAIL_SENDER);
+
+        // Create mail item list with birthday cake
+        List<Mail.MailItem> mailItems = new ArrayList<>();
+        mailItems.add(new Mail.MailItem(BIRTHDAY_GIFT_ID, BIRTHDAY_GIFT_COUNT));
+
+        // Calculate expiration time (7 days from now)
+        long expireTime = System.currentTimeMillis() / 1000 + (7 * 24 * 60 * 60);
+
+        // Create mail
+        Mail birthdayMail = new Mail(mailContent, mailItems, expireTime);
+
+        // Send mail to player
+        player.getMailHandler().sendMail(birthdayMail);
+
+        // Log the action
+        Grasscutter.getLogger().info("Birthday gift sent to " + player.getNickname() + " (UID: " + player.getUid() + ")");
+
+        // Mark that player received birthday gift today
+        markBirthdayGiftReceived(player);
+    }
+
+    /**
+     * Checks if the player has already received a birthday gift today.
+     * Uses player properties to store this information.
+     *
+     * @param player The player to check
+     * @return True if the player has received a birthday gift today, false otherwise
+     */
+    private static boolean hasReceivedBirthdayGiftToday(Player player) {
+        // Get current date as a string in format YYYYMMDD
+        LocalDate currentDate = LocalDate.now(ZoneId.systemDefault());
+        String dateString = String.format("%04d%02d%02d", 
+                currentDate.getYear(), 
+                currentDate.getMonthValue(), 
+                currentDate.getDayOfMonth());
+
+        // Convert to integer for storage in player properties
+        int dateValue = Integer.parseInt(dateString);
+
+        // Check if player has a property for the last birthday gift date
+        Integer lastGiftDate = player.getProperties().get(PlayerProperties.LAST_BIRTHDAY_GIFT_DATE);
+
+        return lastGiftDate != null && lastGiftDate == dateValue;
+    }
+
+    /**
+     * Marks that the player has received a birthday gift today.
+     *
+     * @param player The player to mark
+     */
+    private static void markBirthdayGiftReceived(Player player) {
+        // Get current date as a string in format YYYYMMDD
+        LocalDate currentDate = LocalDate.now(ZoneId.systemDefault());
+        String dateString = String.format("%04d%02d%02d", 
+                currentDate.getYear(), 
+                currentDate.getMonthValue(), 
+                currentDate.getDayOfMonth());
+
+        // Convert to integer for storage in player properties
+        int dateValue = Integer.parseInt(dateString);
+
+        // Store the date in player properties
+        player.getProperties().put(PlayerProperties.LAST_BIRTHDAY_GIFT_DATE, dateValue);
+
+        // Save player data
+        player.save();
+    }
+
+    /**
+     * Constants for player properties related to birthday gifts.
+     */
+    private static class PlayerProperties {
+        public static final int LAST_BIRTHDAY_GIFT_DATE = 10001; // Custom property ID
+    }
+}

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

@@ -11,6 +11,7 @@
 import emu.grasscutter.game.achievement.Achievements;
 import emu.grasscutter.game.activity.ActivityManager;
 import emu.grasscutter.game.avatar.*;
+import emu.grasscutter.game.mail.BirthdayMailSystem;
 import emu.grasscutter.game.battlepass.BattlePassManager;
 import emu.grasscutter.game.city.CityInfoData;
 import emu.grasscutter.game.entity.GameEntity;
@@ -1469,6 +1470,9 @@ public void onLogin() {
 
         // First notify packets sent
         this.hasSentLoginPackets = true;
+
+        // Check if today is player's birthday and send gift if needed
+        BirthdayMailSystem.checkBirthdayAndSendGift(this);
 
         // Set session state
         session.setState(SessionState.ACTIVE);