Add weather command

Signed-off-by: Jaida Wu <mlgmxyysd@meowcat.org>

src/main/java/emu/grasscutter/command/commands/Weather.java

@@ -0,0 +1,39 @@
+package emu.grasscutter.command.commands;
+
+import emu.grasscutter.command.Command;
+import emu.grasscutter.command.CommandHandler;
+import emu.grasscutter.game.GenshinPlayer;
+import emu.grasscutter.game.props.ClimateType;
+import emu.grasscutter.server.packet.send.PacketSceneAreaWeatherNotify;
+
+import java.util.List;
+
+@Command(label = "weather", usage = "weather <weatherId>",
+        description = "Changes the weather.", aliases = {"w"}, permission = "player.weather")
+public class Weather implements CommandHandler {
+
+    @Override
+    public void onCommand(GenshinPlayer sender, List<String> args) {
+        if (sender == null) {
+            CommandHandler.sendMessage(null, "Run this command in-game.");
+            return;
+        }
+
+        if (args.size() < 1) {
+            CommandHandler.sendMessage(sender, "Usage: weather <weatherId>");
+            return;
+        }
+
+        try {
+            int weatherId = Integer.parseInt(args.get(0));
+
+            ClimateType climate = ClimateType.getTypeByValue(weatherId);
+
+            sender.getScene().setClimate(climate);
+            sender.getScene().broadcastPacket(new PacketSceneAreaWeatherNotify(sender));
+            CommandHandler.sendMessage(sender, "Changed weather to " + weatherId);
+        } catch (NumberFormatException ignored) {
+            CommandHandler.sendMessage(sender, "Invalid weather ID.");
+        }
+    }
+}