implement can place at

server/MPClient.ts

@@ -272,7 +272,7 @@ export class MPClient {
 			return;
 		}
 
-		if (itemStack.isBlock) {
+		if (itemStack.isBlock && Block.blocks[itemStack.itemID].behaviour.canPlaceBlockAt(this.entity.world, this.diggingAt.x, this.diggingAt.y, this.diggingAt.z)) {
 			if (this.entity.world.getBlockId(this.diggingAt.x, this.diggingAt.y, this.diggingAt.z) === 0) {
 				itemStack.size--;
 				this.entity.world.setBlockAndMetadataWithNotify(this.diggingAt.x, this.diggingAt.y, this.diggingAt.z, itemStack.itemID, itemStack.damage);

server/blocks/Block.ts

@@ -98,6 +98,7 @@ export class Block {
 	}
 
 	public setBehaviour(value:IBlockBehaviour) {
+		value.block = this;
 		this.behaviour = value;
 		return this;
 	}

server/blocks/BlockBehaviorSugarcane.ts

@@ -11,6 +11,35 @@ export class BlockBehaviourSugarcane extends BlockBehaviour {
 		}
 	}
 
+	public canPlaceBlockAt(world: World, x: number, y: number, z: number) {
+		const blockBelow = world.getBlockId(x, y - 1, z);
+
+		if (blockBelow === this.block.blockId) {
+			return true;
+		}
+
+		// Check if right ground block
+		if (blockBelow !== Block.grass.blockId && blockBelow !== Block.dirt.blockId) {
+			return false;
+		}
+
+		// Check if water is around
+		if (world.getBlockId(x - 1, y - 1, z) === Block.waterStill.blockId) {
+			return true;
+		}
+		if (world.getBlockId(x + 1, y - 1, z) === Block.waterStill.blockId) {
+			return true;
+		}
+		if (world.getBlockId(x, y - 1, z - 1) === Block.waterStill.blockId) {
+			return true;
+		}
+		if (world.getBlockId(x, y - 1, z + 1) === Block.waterStill.blockId) {
+			return true;
+		}
+
+		return false;
+	}
+
 	public getBoundingBox() {
 		return AABB.getAABB(0, 0, 0, 0, 0, 0);
 	}

server/blocks/BlockBehaviour.ts

@@ -1,12 +1,16 @@
 import AABB from "../AABB";
 import Random from "../Random";
 import { World } from "../World";
+import { Block } from "./Block";
 import { IBlockBehaviour } from "./IBlockBehaviour";
 
 export class BlockBehaviour implements IBlockBehaviour {
+	public block!:Block;
+
 	public neighborBlockChange(world:World, x:number, y:number, z:number, blockId:number) {}
 	public droppedItem(blockId:number) { return blockId; }
 	public droppedCount(blockId:number) { return 1; }
 	public getBoundingBox(x:number, y:number, z:number) { return AABB.getAABB(0 + x, 0 + y, 0 + z, 1 + x, 1 + y, 1 + z); }
 	public randomTick(world:World, x:number, y:number, z:number, random:Random) {}
+	public canPlaceBlockAt(world:World, x:number, y:number, z:number) { return true; }
 }

server/blocks/IBlockBehaviour.ts

@@ -1,9 +1,15 @@
 import AABB from "../AABB";
+import Random from "../Random";
 import { World } from "../World";
+import { Block } from "./Block";
 
 export interface IBlockBehaviour {
+	block:Block,
+
 	neighborBlockChange(world:World, x:number, y:number, z:number, blockId:number): void,
 	droppedItem: (blockId:number) => number,
 	droppedCount: (blockId:number) => number,
 	getBoundingBox: (x:number, y:number, z:number) => AABB,
+	randomTick: (world:World, x:number, y:number, z:number, random:Random) => void,
+	canPlaceBlockAt: (world:World, x:number, y:number, z:number) => boolean
 }

server/packets/WindowClick.ts

@@ -0,0 +1,54 @@
+import { createWriter, IReader, Endian } from "bufferstuff";
+import { IPacket } from "./IPacket";
+import { Packet } from "../enums/Packet";
+
+export class PacketWindowClick implements IPacket {
+	public packetId = Packet.WindowClick;
+	public windowId:number;
+	public slot:number;
+	public rightClick:boolean;
+	public actionNumber:number;
+	public shift:boolean;
+	public itemId:number;
+	public itemCount:number;
+	public itemUses:number;
+
+	public constructor(windowId?:number, slot?:number, rightClick?:boolean, actionNumber?:number, shift?:boolean, itemId?:number, itemCount?:number, itemUses?:number) {
+		if (typeof(windowId) === "number" && typeof(slot) === "number" && typeof(rightClick) === "boolean" && typeof(actionNumber) === "number" && typeof(shift) === "boolean" && typeof(itemId) === "number" && typeof(itemCount) ===  "number" && typeof(itemUses) === "number") {
+			this.windowId = windowId;
+			this.slot = slot;
+			this.rightClick = rightClick;
+			this.actionNumber = actionNumber;
+			this.shift = shift;
+			this.itemId = itemId;
+			this.itemCount = itemCount;
+			this.itemUses = itemUses;
+		} else {
+			this.windowId = Number.MIN_VALUE;
+			this.slot = Number.MIN_VALUE;
+			this.rightClick = false;
+			this.actionNumber = Number.MIN_VALUE;
+			this.shift = false;
+			this.itemId = Number.MIN_VALUE;
+			this.itemCount = Number.MIN_VALUE;
+			this.itemUses = Number.MIN_VALUE;
+		}
+	}
+
+	public readData(reader:IReader) {
+		this.windowId = reader.readByte();
+		this.slot = reader.readShort();
+		this.rightClick = reader.readBool();
+		this.actionNumber = reader.readShort();
+		this.shift = reader.readBool();
+		this.itemId = reader.readShort();
+		this.itemCount = reader.readByte();
+		this.itemUses = reader.readShort();
+
+		return this;
+	}
+
+	public writeData() {
+		return createWriter(Endian.BE, 4).writeUByte(this.packetId).writeByte(this.windowId).writeShort(this.slot).writeBool(this.rightClick).writeShort(this.actionNumber).writeShort(this.itemId).writeByte(this.itemCount).writeShort(this.itemUses).toBuffer();
+	}
+}