Add survival-style block pick support (#526)

* Add survival-style block pick support

* Add BedrockBlockPickRequestPacketTranslator.java

* Remove unnecessary println

* Edit styling and add null check

* Fix compile error

* Remove nesting and unnecessary check

* Further reduce nesting

* Change 1-line statements and add missing comment

* Fix creating translator

* Fix imports

connector/src/main/java/org/geysermc/connector/network/translators/bedrock/BedrockBlockPickRequestPacketTranslator.java

@@ -0,0 +1,104 @@
+/*
+ * Copyright (c) 2019-2020 GeyserMC. http://geysermc.org
+ *
+ *  Permission is hereby granted, free of charge, to any person obtaining a copy
+ *  of this software and associated documentation files (the "Software"), to deal
+ *  in the Software without restriction, including without limitation the rights
+ *  to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ *  copies of the Software, and to permit persons to whom the Software is
+ *  furnished to do so, subject to the following conditions:
+ *
+ *  The above copyright notice and this permission notice shall be included in
+ *  all copies or substantial portions of the Software.
+ *
+ *  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ *  IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ *  FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ *  AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ *  LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ *  OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+ *  THE SOFTWARE.
+ *
+ *  @author GeyserMC
+ *  @link https://github.com/GeyserMC/Geyser
+ *
+ */
+
+package org.geysermc.connector.network.translators.bedrock;
+
+import com.github.steveice10.mc.protocol.data.game.world.block.BlockState;
+import com.github.steveice10.mc.protocol.packet.ingame.client.window.ClientMoveItemToHotbarPacket;
+import com.nukkitx.math.vector.Vector3i;
+import com.nukkitx.protocol.bedrock.packet.BlockPickRequestPacket;
+import com.nukkitx.protocol.bedrock.packet.PlayerHotbarPacket;
+import org.geysermc.connector.entity.Entity;
+import org.geysermc.connector.inventory.Inventory;
+import org.geysermc.connector.network.session.GeyserSession;
+import org.geysermc.connector.network.translators.PacketTranslator;
+import org.geysermc.connector.network.translators.Translator;
+import org.geysermc.connector.network.translators.item.ItemEntry;
+import org.geysermc.connector.network.translators.world.block.BlockTranslator;
+import org.geysermc.connector.network.translators.item.ItemTranslator;
+import org.geysermc.connector.network.translators.Translators;
+
+@Translator(packet = BlockPickRequestPacket.class)
+public class BedrockBlockPickRequestPacketTranslator extends PacketTranslator<BlockPickRequestPacket> {
+
+    @Override
+    public void translate(BlockPickRequestPacket packet, GeyserSession session) {
+        Vector3i vector = packet.getBlockPosition();
+        BlockState blockToPick = session.getConnector().getWorldManager().getBlockAt(session, vector.getX(), vector.getY(), vector.getZ());
+        
+        // Block is air - chunk caching is probably off
+        if (blockToPick.getId() == 0) {
+            return;
+        }
+
+        // Get the inventory to choose a slot to pick
+        Inventory inventory = session.getInventoryCache().getOpenInventory();
+        if (inventory == null) {
+            inventory = session.getInventory();
+        }
+
+        String targetIdentifier = BlockTranslator.getJavaIdBlockMap().inverse().get(blockToPick).split("\\[")[0];
+        ItemTranslator itemTranslator = Translators.getItemTranslator();
+
+        // Check hotbar for item
+        for (int i = 36; i < 45; i++) {
+            if (inventory.getItem(i) == null) {
+                continue;
+            }
+            ItemEntry item = itemTranslator.getItem(inventory.getItem(i));
+            // If this isn't the item we're looking for
+            if (!item.getJavaIdentifier().equals(targetIdentifier)) {
+                continue;
+            }
+            
+            PlayerHotbarPacket hotbarPacket = new PlayerHotbarPacket();
+            hotbarPacket.setContainerId(0);
+            // Java inventory slot to hotbar slot ID
+            hotbarPacket.setSelectedHotbarSlot(i - 36);
+            hotbarPacket.setSelectHotbarSlot(true);
+            session.sendUpstreamPacket(hotbarPacket);
+            session.getInventory().setHeldItemSlot(i - 36);
+            // Don't check inventory if item was in hotbar
+            return;
+        }
+
+        // Check inventory for item
+        for (int i = 9; i < 36; i++) {
+            if (inventory.getItem(i) == null) {
+                continue;
+            }
+            ItemEntry item = itemTranslator.getItem(inventory.getItem(i));
+            // If this isn't the item we're looking for
+            if (!item.getJavaIdentifier().equals(targetIdentifier)) {
+                continue;
+            }
+            
+            ClientMoveItemToHotbarPacket packetToSend = new ClientMoveItemToHotbarPacket(i); // https://wiki.vg/Protocol#Pick_Item
+            session.sendDownstreamPacket(packetToSend);
+            return;
+        }
+    }
+}