added missing redstone power flag logic

src/block/BlockLegacyMetadata.php

@@ -142,6 +142,8 @@ final class BlockLegacyMetadata{
 	public const LEAVES_FLAG_NO_DECAY = 0x04;
 	public const LEAVES_FLAG_CHECK_DECAY = 0x08;
 
+	public const LECTERN_FLAG_POWERED = 0x04;
+
 	public const LEVER_FLAG_POWERED = 0x08;
 
 	public const LIQUID_FLAG_FALLING = 0x08;

src/block/Lectern.php

@@ -40,13 +40,15 @@ class Lectern extends Transparent{
 
 	protected int $viewedPage = 0;
 	protected ?WritableBookBase $book = null;
+	protected bool $producingSignal = false;
 
 	public function readStateFromData(int $id, int $stateMeta) : void{
-		$this->facing = BlockDataSerializer::readLegacyHorizontalFacing($stateMeta);
+		$this->facing = BlockDataSerializer::readLegacyHorizontalFacing($stateMeta & 0x03);
+		$this->producingSignal = ($stateMeta & BlockLegacyMetadata::LECTERN_FLAG_POWERED) !== 0;
 	}
 
 	public function writeStateToMeta() : int{
-		return BlockDataSerializer::writeLegacyHorizontalFacing($this->facing);
+		return BlockDataSerializer::writeLegacyHorizontalFacing($this->facing) | ($this->producingSignal ? BlockLegacyMetadata::LECTERN_FLAG_POWERED : 0);
 	}
 
 	public function readStateFromWorld() : void{
@@ -68,7 +70,7 @@ class Lectern extends Transparent{
 	}
 
 	public function getStateBitmask() : int{
-		return 0b11;
+		return 0b111;
 	}
 
 	public function getFlammability() : int{
@@ -88,6 +90,14 @@ class Lectern extends Transparent{
 		return [AxisAlignedBB::one()->trim(Facing::UP, 0.1)];
 	}
 
+	public function isProducingSignal() : bool{ return $this->producingSignal; }
+
+	/** @return $this */
+	public function setProducingSignal(bool $producingSignal) : self{
+		$this->producingSignal = $producingSignal;
+		return $this;
+	}
+
 	public function getViewedPage() : int{
 		return $this->viewedPage;
 	}
@@ -124,4 +134,30 @@ class Lectern extends Transparent{
 		}
 		return false;
 	}
+
+	public function onPageTurn(int $newPage) : bool{
+		if($newPage === $this->viewedPage){
+			return true;
+		}
+		if($this->book === null || $newPage >= count($this->book->getPages()) || $newPage < 0){
+			return false;
+		}
+
+		$this->viewedPage = $newPage;
+		if(!$this->producingSignal){
+			$this->producingSignal = true;
+			$this->position->getWorld()->scheduleDelayedBlockUpdate($this->position, 1);
+		}
+
+		$this->position->getWorld()->setBlock($this->position, $this);
+
+		return true;
+	}
+
+	public function onScheduledUpdate() : void{
+		if($this->producingSignal){
+			$this->producingSignal = false;
+			$this->position->getWorld()->setBlock($this->position, $this);
+		}
+	}
 }

src/network/mcpe/handler/InGamePacketHandler.php

@@ -945,14 +945,10 @@ class InGamePacketHandler extends PacketHandler{
 
 		$lectern = $world->getBlockAt($pos->getX(), $pos->getY(), $pos->getZ());
 		if($lectern instanceof Lectern && $this->player->canInteract($lectern->getPosition(), 15)){
-			if($lectern->getViewedPage() === $packet->page){
-				return true;
-			}
-			$book = $lectern->getBook();
-			if($book !== null && count($book->getPages()) === $packet->totalPages && $packet->page >= 0 && $packet->page < $packet->totalPages){
-				$world->setBlock($lectern->getPosition(), $lectern->setViewedPage($packet->page));
-				return true;
+			if(!$lectern->onPageTurn($packet->page)){
+				$this->onFailedBlockAction($lectern->getPosition(), null);
 			}
+			return true;
 		}
 
 		return false;