Adds grappling gun (#16662)

Content.Shared/Projectiles/SharedProjectileSystem.cs

@@ -1,6 +1,9 @@
 using Content.Shared.Projectiles;
+using Content.Shared.Weapons.Ranged.Components;
 using Robust.Shared.Map;
+using Robust.Shared.Physics;
 using Robust.Shared.Physics.Events;
+using Robust.Shared.Physics.Systems;
 using Robust.Shared.Serialization;
 
 namespace Content.Shared.Projectiles
@@ -9,10 +12,26 @@ namespace Content.Shared.Projectiles
     {
         public const string ProjectileFixture = "projectile";
 
+        [Dependency] private readonly SharedPhysicsSystem _physics = default!;
+        [Dependency] private readonly SharedTransformSystem _transform = default!;
+
         public override void Initialize()
         {
             base.Initialize();
             SubscribeLocalEvent<ProjectileComponent, PreventCollideEvent>(PreventCollision);
+            SubscribeLocalEvent<EmbeddableProjectileComponent, StartCollideEvent>(OnEmbedCollide);
+        }
+
+        private void OnEmbedCollide(EntityUid uid, EmbeddableProjectileComponent component, ref StartCollideEvent args)
+        {
+            if (!TryComp<ProjectileComponent>(uid, out var projectile))
+                return;
+
+            _physics.SetLinearVelocity(uid, Vector2.Zero, body: args.OurBody);
+            _physics.SetBodyType(uid, BodyType.Static, body: args.OurBody);
+            _transform.SetParent(uid, args.OtherEntity);
+            var ev = new ProjectileEmbedEvent(projectile.Shooter, projectile.Weapon, args.OtherEntity);
+            RaiseLocalEvent(uid, ref ev);
         }
 
         private void PreventCollision(EntityUid uid, ProjectileComponent component, ref PreventCollideEvent args)
@@ -25,7 +44,8 @@ namespace Content.Shared.Projectiles
 
         public void SetShooter(ProjectileComponent component, EntityUid uid)
         {
-            if (component.Shooter == uid) return;
+            if (component.Shooter == uid)
+                return;
 
             component.Shooter = uid;
             Dirty(component);