feat(AutoSign): Add AutoSign Module

src/main/java/com/lambda/mixin/entity/ClientPlayerEntityMixin.java

@@ -19,10 +19,7 @@
 
 import com.lambda.Lambda;
 import com.lambda.event.EventFlow;
-import com.lambda.event.events.MovementEvent;
-import com.lambda.event.events.PlayerEvent;
-import com.lambda.event.events.PlayerPacketEvent;
-import com.lambda.event.events.TickEvent;
+import com.lambda.event.events.*;
 import com.lambda.interaction.managers.rotating.Rotation;
 import com.lambda.interaction.managers.rotating.RotationManager;
 import com.lambda.module.modules.movement.ElytraFly;
@@ -38,6 +35,7 @@
 import com.llamalad7.mixinextras.injector.wrapoperation.WrapOperation;
 import com.llamalad7.mixinextras.sugar.Local;
 import com.mojang.authlib.GameProfile;
+import net.minecraft.block.entity.SignBlockEntity;
 import net.minecraft.client.gui.screen.Screen;
 import net.minecraft.client.input.Input;
 import net.minecraft.client.network.AbstractClientPlayerEntity;
@@ -71,6 +69,13 @@ public ClientPlayerEntityMixin(ClientWorld world, GameProfile profile) {
         super(world, profile);
     }
 
+    @Inject(method = "openEditSignScreen", at = @At("HEAD"), cancellable = true)
+    private void onOpenEditSignScreen(SignBlockEntity sign, boolean front, CallbackInfo ci) {
+        if (EventFlow.post(new GuiEvent.SignEditorOpen(sign, front)).isCanceled()) {
+            ci.cancel();
+        }
+    }
+
     @WrapOperation(method = "move", at = @At(value = "INVOKE", target = "Lnet/minecraft/client/network/AbstractClientPlayerEntity;move(Lnet/minecraft/entity/MovementType;Lnet/minecraft/util/math/Vec3d;)V"))
     private void wrapMove(ClientPlayerEntity instance, MovementType movementType, Vec3d vec3d, Operation<Void> original) {
         EventFlow.post(new MovementEvent.Player.Pre(movementType, vec3d));

src/main/kotlin/com/lambda/event/events/GuiEvent.kt

@@ -18,6 +18,9 @@
 package com.lambda.event.events
 
 import com.lambda.event.Event
+import com.lambda.event.callback.Cancellable
+import com.lambda.event.callback.ICancellable
+import net.minecraft.block.entity.SignBlockEntity
 
 sealed class GuiEvent {
     /**
@@ -33,4 +36,12 @@ sealed class GuiEvent {
      * By default, the game's framebuffer is bound.
      */
     data object EndFrame : Event
+
+    /**
+     * Triggered when the sign editor GUI is opened. Can be canceled.
+     */
+    data class SignEditorOpen(
+        var sign: SignBlockEntity,
+        var front: Boolean
+    ) : ICancellable by Cancellable()
 }

src/main/kotlin/com/lambda/module/modules/player/AutoSign.kt

@@ -0,0 +1,97 @@
+/*
+ * Copyright 2026 Lambda
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+package com.lambda.module.modules.player
+
+import com.ibm.icu.util.Calendar
+import com.lambda.event.events.GuiEvent
+import com.lambda.event.listener.SafeListener.Companion.listen
+import com.lambda.module.Module
+import com.lambda.module.tag.ModuleTag
+import net.minecraft.block.entity.HangingSignBlockEntity
+import net.minecraft.client.gui.screen.ingame.AbstractSignEditScreen
+import net.minecraft.client.gui.screen.ingame.HangingSignEditScreen
+import net.minecraft.client.gui.screen.ingame.SignEditScreen
+import net.minecraft.network.packet.c2s.play.UpdateSignC2SPacket
+import java.util.*
+
+
+class AutoSign : Module(
+	name = "AutoSign",
+	description = """Auto fills signs with customizable text. Leave lines empty to skip them. Supports data formatting with:
+		|<d> - Day of month (1-31)
+		|<dd> - Day of month (01-31)
+		|<M> - Month (1-12)
+        |<MM> - Month (01-12)
+		|<MMM> - Month (short name, e.g., Jan)
+        |<MMMM> - Month (full name, e.g., January)
+		|<yy> - Year (last two digits, e.g., 26)
+		|<yyyy> - Year (e.g., 2026)
+        |<HH> - Hour (00-23)
+		|<mm> - Minute (00-59)
+        |<ss> - Second (00-59)
+	""".trimMargin(),
+	tag = ModuleTag.PLAYER
+) {
+	var autoWrite by setting("Auto Write", true)
+	var line1 by setting("Line 1", "Welcome to Lambda!") { autoWrite }
+	var line2 by setting("Line 2", "Enjoy your stay.") { autoWrite }
+	var line3 by setting("Line 3", "Have fun!") { autoWrite }
+	var line4 by setting("Line 4", "Lambda <dd>/<M>/<yy>") { autoWrite }
+	var writeOnFront by setting("Write Front", true, description = "Write on front side of the sign") { autoWrite }
+
+	var autoClose by setting("Auto Close", true)
+
+	init {
+		listen<GuiEvent.SignEditorOpen> { event ->
+			val lines = Array(4) { i -> event.component1().frontText.getMessages(false)[i].string }
+			if (autoWrite) {
+				var formatLines = arrayOf(line1, line2, line3, line4)
+				val calendar = Calendar.getInstance()
+				val month = calendar.get(Calendar.MONTH) + 1 // Months are 0-based in Calendar
+
+				for (i in 0 until 4) {
+					val formattedLine = formatLines[i]
+						.replace("<dd>", String.format($$"%1$td", Date()))
+						.replace("<d>", String.format($$"%1$te", Date()))
+						.replace("<M>", month.toString())
+						.replace("<MM>", String.format("%02d", month))
+						.replace("<MMM>", String.format($$"%1$tb", Date()))
+						.replace("<MMMM>", String.format($$"%1$tB", Date()))
+						.replace("<yy>", String.format($$"%1$ty", Date()))
+						.replace("<yyyy>", String.format($$"%1$tY", Date()))
+						.replace("<HH>", String.format($$"%1$tH", Date()))
+						.replace("<mm>", String.format($$"%1$tM", Date()))
+						.replace("<ss>", String.format($$"%1$tS", Date()))
+
+					if (formattedLine.isNotEmpty()) lines[i] = String.format(formattedLine, Date())
+				}
+			}
+
+			var editor: AbstractSignEditScreen = if (event.sign is HangingSignBlockEntity) HangingSignEditScreen(event.sign, true, mc.shouldFilterText())
+			else SignEditScreen(event.sign, true, mc.shouldFilterText())
+			for (i in 0 until 4) editor.messages[i] = lines[i]
+			if (autoClose) {
+				if (writeOnFront) mc.networkHandler?.sendPacket(UpdateSignC2SPacket(event.sign.pos, true, editor.messages[0], editor.messages[1], editor.messages[2], editor.messages[3]))
+				else mc.networkHandler?.sendPacket(UpdateSignC2SPacket(event.sign.pos, false, editor.messages[0], editor.messages[1], editor.messages[2], editor.messages[3]))
+			} else {
+				mc.setScreen(editor)
+			}
+			event.cancel()
+		}
+	}
+}

src/main/resources/lambda.accesswidener

@@ -123,3 +123,6 @@ transitive-accessible method net/minecraft/item/BlockItem getPlacementState (Lne
 transitive-accessible method net/minecraft/block/AbstractBlock getPickStack (Lnet/minecraft/world/WorldView;Lnet/minecraft/util/math/BlockPos;Lnet/minecraft/block/BlockState;Z)Lnet/minecraft/item/ItemStack;
 transitive-accessible field net/minecraft/client/gui/screen/ingame/HandledScreen focusedSlot Lnet/minecraft/screen/slot/Slot;
 transitive-accessible field net/minecraft/registry/SimpleRegistry frozen Z
+
+# AutoSign / GuiEvent.SignEditorOpen event
+accessible field net/minecraft/client/gui/screen/ingame/AbstractSignEditScreen messages [Ljava/lang/String;