conveyor & recycler ecs (#4537)

* conveyor done, recycler still todo

* done, just need to suss out the physics part. pinged sloth about it

* ship it

Content.Server/Conveyor/ConveyorSystem.cs

@@ -1,15 +1,29 @@
-using Content.Server.MachineLinking.Events;
+using System.Collections.Generic;
+using Content.Server.Items;
+using Content.Server.MachineLinking.Events;
 using Content.Server.MachineLinking.Models;
+using Content.Server.Power.Components;
+using Content.Server.Recycling.Components;
 using Content.Server.Stunnable.Components;
+using Content.Shared.Conveyor;
 using Content.Shared.MachineLinking;
+using Content.Shared.Movement.Components;
 using Content.Shared.Notification.Managers;
+using Robust.Server.GameObjects;
+using Robust.Shared.Containers;
 using Robust.Shared.GameObjects;
+using Robust.Shared.IoC;
 using Robust.Shared.Localization;
+using Robust.Shared.Maths;
+using Robust.Shared.Physics;
+using Robust.Shared.Physics.Dynamics;
 
 namespace Content.Server.Conveyor
 {
     public class ConveyorSystem : EntitySystem
     {
+        [Dependency] private IEntityLookup _entityLookup = default!;
+
         public override void Initialize()
         {
             base.Initialize();
@@ -17,6 +31,27 @@ namespace Content.Server.Conveyor
             SubscribeLocalEvent<ConveyorComponent, SignalReceivedEvent>(OnSignalReceived);
             SubscribeLocalEvent<ConveyorComponent, PortDisconnectedEvent>(OnPortDisconnected);
             SubscribeLocalEvent<ConveyorComponent, LinkAttemptEvent>(OnLinkAttempt);
+            SubscribeLocalEvent<ConveyorComponent, PowerChangedEvent>(OnPowerChanged);
+        }
+
+        private void OnPowerChanged(EntityUid uid, ConveyorComponent component, PowerChangedEvent args)
+        {
+            UpdateAppearance(component);
+        }
+
+        private void UpdateAppearance(ConveyorComponent component)
+        {
+            if (component.Owner.TryGetComponent<AppearanceComponent>(out var appearance))
+            {
+                if (component.Owner.TryGetComponent<ApcPowerReceiverComponent>(out var receiver) && receiver.Powered)
+                {
+                    appearance.SetData(ConveyorVisuals.State, component.State);
+                }
+                else
+                {
+                    appearance.SetData(ConveyorVisuals.State, ConveyorState.Off);
+                }
+            }
         }
 
         private void OnLinkAttempt(EntityUid uid, ConveyorComponent component, LinkAttemptEvent args)
@@ -35,7 +70,7 @@ namespace Content.Server.Conveyor
 
         private void OnPortDisconnected(EntityUid uid, ConveyorComponent component, PortDisconnectedEvent args)
         {
-            component.SetState(TwoWayLeverSignal.Middle);
+            SetState(component, TwoWayLeverSignal.Middle);
         }
 
         private void OnSignalReceived(EntityUid uid, ConveyorComponent component, SignalReceivedEvent args)
@@ -43,9 +78,92 @@ namespace Content.Server.Conveyor
             switch (args.Port)
             {
                 case "state":
-                    component.SetState((TwoWayLeverSignal) args.Value!);
+                    SetState(component, (TwoWayLeverSignal) args.Value!);
                     break;
             }
         }
+
+        private void SetState(ConveyorComponent component, TwoWayLeverSignal signal)
+        {
+            component.State = signal switch
+            {
+                TwoWayLeverSignal.Left => ConveyorState.Reversed,
+                TwoWayLeverSignal.Middle => ConveyorState.Off,
+                TwoWayLeverSignal.Right => ConveyorState.Forward,
+                _ => ConveyorState.Off
+            };
+            UpdateAppearance(component);
+        }
+
+        public bool CanRun(ConveyorComponent component)
+        {
+            if (component.State == ConveyorState.Off)
+            {
+                return false;
+            }
+
+            if (component.Owner.TryGetComponent(out ApcPowerReceiverComponent? receiver) &&
+                !receiver.Powered)
+            {
+                return false;
+            }
+
+            if (component.Owner.HasComponent<ItemComponent>())
+            {
+                return false;
+            }
+
+            return true;
+        }
+
+        /// <summary>
+        ///     Calculates the angle in which entities on top of this conveyor
+        ///     belt are pushed in
+        /// </summary>
+        /// <returns>
+        ///     The angle when taking into account if the conveyor is reversed
+        /// </returns>
+        public Angle GetAngle(ConveyorComponent component)
+        {
+            var adjustment = component.State == ConveyorState.Reversed ? MathHelper.Pi/2 : -MathHelper.Pi/2;
+            var radians = MathHelper.DegreesToRadians(component.Angle);
+
+            return new Angle(component.Owner.Transform.LocalRotation.Theta + radians + adjustment);
+        }
+
+        public IEnumerable<(IEntity, IPhysBody)> GetEntitiesToMove(ConveyorComponent comp)
+        {
+            //todo uuuhhh cache this
+            foreach (var entity in _entityLookup.GetEntitiesIntersecting(comp.Owner, LookupFlags.Approximate))
+            {
+                if (entity.Deleted)
+                {
+                    continue;
+                }
+
+                if (entity == comp.Owner)
+                {
+                    continue;
+                }
+
+                if (!entity.TryGetComponent(out IPhysBody? physics) ||
+                    physics.BodyType == BodyType.Static || physics.BodyStatus == BodyStatus.InAir || entity.IsWeightless())
+                {
+                    continue;
+                }
+
+                if (entity.HasComponent<IMapGridComponent>())
+                {
+                    continue;
+                }
+
+                if (entity.IsInContainer())
+                {
+                    continue;
+                }
+
+                yield return (entity, physics);
+            }
+        }
     }
 }