Unit enter payload command

core/assets/bundles/bundle.properties

@@ -354,6 +354,7 @@ command.rebuild = Rebuild
 command.assist = Assist Player
 command.move = Move
 command.boost = Boost
+command.enterPayload = Enter Payload Block
 command.loadUnits = Load Units
 command.loadBlocks = Load Blocks
 command.unloadPayload = Unload Payload

core/src/mindustry/ai/UnitCommand.java

@@ -17,7 +17,7 @@ public class UnitCommand extends MappableContent{
     @Deprecated
     public static final Seq<UnitCommand> all = new Seq<>();
 
-    public static UnitCommand moveCommand, repairCommand, rebuildCommand, assistCommand, mineCommand, boostCommand, loadUnitsCommand, loadBlocksCommand, unloadPayloadCommand;
+    public static UnitCommand moveCommand, repairCommand, rebuildCommand, assistCommand, mineCommand, boostCommand, enterPayloadCommand, loadUnitsCommand, loadBlocksCommand, unloadPayloadCommand;
 
     /** Name of UI icon (from Icon class). */
     public final String icon;
@@ -87,6 +87,11 @@ public class UnitCommand extends MappableContent{
             drawTarget = true;
             resetTarget = false;
         }};
+        enterPayloadCommand = new UnitCommand("enterPayload", "downOpen", Binding.unit_command_enter_payload, null){{
+            switchToMove = false;
+            drawTarget = true;
+            resetTarget = false;
+        }};
         loadUnitsCommand = new UnitCommand("loadUnits", "upload", Binding.unit_command_load_units, null){{
             switchToMove = false;
             drawTarget = true;

core/src/mindustry/ai/types/CommandAI.java

@@ -20,6 +20,7 @@ public class CommandAI extends AIController{
     protected static final int maxCommandQueueSize = 50, avoidInterval = 10;
     protected static final Vec2 vecOut = new Vec2(), vecMovePos = new Vec2();
     protected static final boolean[] noFound = {false};
+    protected static final UnitPayload tmpPayload = new UnitPayload(null);
 
     public Seq<Position> commandQueue = new Seq<>(5);
     public @Nullable Vec2 targetPos;
@@ -145,6 +146,15 @@ public class CommandAI extends AIController{
             }
         }
 
+        if(!net.client() && command == UnitCommand.enterPayloadCommand && unit.buildOn() != null && (targetPos == null || (world.buildWorld(targetPos.x, targetPos.y) != null && world.buildWorld(targetPos.x, targetPos.y) == unit.buildOn()))){
+            var build = unit.buildOn();
+            tmpPayload.unit = unit;
+            if(build.team == unit.team && build.acceptPayload(build, tmpPayload)){
+                Call.unitEnteredPayload(unit, build);
+                return; //no use updating after this, the unit is gone!
+            }
+        }
+
         //acquiring naval targets isn't supported yet, so use the fallback dumb AI
         if(unit.team.isAI() && unit.team.rules().rtsAi && unit.type.naval){
             if(fallback == null) fallback = new GroundAI();
@@ -198,7 +208,8 @@ public class CommandAI extends AIController{
             vecOut.set(targetPos);
             vecMovePos.set(targetPos);
 
-            if(group != null && group.valid && groupIndex < group.units.size){
+            //the enter payload command requires an exact position
+            if(group != null && group.valid && groupIndex < group.units.size && command != UnitCommand.enterPayloadCommand){
                 vecMovePos.add(group.positions[groupIndex * 2], group.positions[groupIndex * 2 + 1]);
             }
 
@@ -295,6 +306,11 @@ public class CommandAI extends AIController{
     }
 
     void finishPath(){
+        //the enter payload command never finishes until they are actually accepted
+        if(command == UnitCommand.enterPayloadCommand && commandQueue.size == 0 && targetPos != null && world.buildWorld(targetPos.x, targetPos.y) != null && world.buildWorld(targetPos.x, targetPos.y).block.acceptsPayloads){
+            return;
+        }
+
         Vec2 prev = targetPos;
         targetPos = null;
 

core/src/mindustry/input/Binding.java

@@ -56,6 +56,7 @@ public enum Binding implements KeyBind{
     unit_command_assist(KeyCode.unset),
     unit_command_mine(KeyCode.unset),
     unit_command_boost(KeyCode.unset),
+    unit_command_enter_payload(KeyCode.unset),
     unit_command_load_units(KeyCode.unset),
     unit_command_load_blocks(KeyCode.unset),
     unit_command_unload_payload(KeyCode.unset),

core/src/mindustry/input/InputHandler.java

@@ -557,6 +557,31 @@ public abstract class InputHandler implements InputProcessor, GestureListener{
         }
     }
 
+    @Remote(called = Loc.server)
+    public static void unitEnteredPayload(Unit unit, Building build){
+        if(unit == null || build == null || unit.team != build.team) return;
+
+        unit.remove();
+
+        //reset the enter command
+        if(unit.controller() instanceof CommandAI ai && ai.command == UnitCommand.enterPayloadCommand){
+            ai.clearCommands();
+            ai.command = UnitCommand.moveCommand;
+        }
+
+        //clear removed state of unit so it can be synced
+        if(Vars.net.client()){
+            Vars.netClient.clearRemovedEntity(unit.id);
+        }
+
+        UnitPayload unitPay = new UnitPayload(unit);
+
+        if(build.acceptPayload(build, unitPay)){
+            Fx.unitDrop.at(build);
+            build.handlePayload(build, unitPay);
+        }
+    }
+
     @Remote(targets = Loc.client, called = Loc.server)
     public static void dropItem(Player player, float angle){
         if(player == null) return;

core/src/mindustry/type/UnitType.java

@@ -810,7 +810,7 @@ public class UnitType extends UnlockableContent implements Senseable{
         if(commands.length == 0){
             Seq<UnitCommand> cmds = new Seq<>(UnitCommand.class);
 
-            cmds.add(UnitCommand.moveCommand);
+            cmds.add(UnitCommand.moveCommand, UnitCommand.enterPayloadCommand);
 
             if(canBoost){
                 cmds.add(UnitCommand.boostCommand);

core/src/mindustry/world/Block.java

@@ -57,6 +57,8 @@ public class Block extends UnlockableContent implements Senseable{
     public boolean conductivePower = false;
     /** If true, this block can output payloads; affects blending. */
     public boolean outputsPayload = false;
+    /** If true, this block can input payloads; affects unit payload enter behavior. */
+    public boolean acceptsPayloads = false;
     /** If true, payloads will attempt to move into this block. */
     public boolean acceptsPayload = false;
     /** Visual flag use for blending of certain transportation blocks. */

core/src/mindustry/world/blocks/payloads/BlockProducer.java

@@ -30,6 +30,7 @@ public abstract class BlockProducer extends PayloadBlock{
         hasItems = true;
         solid = true;
         hasPower = true;
+        acceptsPayloads = false;
         rotate = true;
         regionRotated1 = 1;
 

core/src/mindustry/world/blocks/payloads/PayloadBlock.java

@@ -25,6 +25,7 @@ public class PayloadBlock extends Block{
         update = true;
         sync = true;
         group = BlockGroup.payloads;
+        acceptsPayloads = true;
         envEnabled |= Env.space | Env.underwater;
     }
 

core/src/mindustry/world/blocks/payloads/PayloadConveyor.java

@@ -30,6 +30,7 @@ public class PayloadConveyor extends Block{
         update = true;
         outputsPayload = true;
         noUpdateDisabled = true;
+        acceptsPayloads = true;
         priority = TargetPriority.transport;
         envEnabled |= Env.space | Env.underwater;
         sync = true;

core/src/mindustry/world/blocks/payloads/PayloadSource.java

@@ -37,6 +37,7 @@ public class PayloadSource extends PayloadBlock{
         noUpdateDisabled = true;
         clearOnDoubleTap = true;
         regionRotated1 = 1;
+        acceptsPayloads = false;
         commandable = true;
 
         config(Block.class, (PayloadSourceBuild build, Block block) -> {