Gun stuff (#132)

* Guns can now be fully automatic.

Take that BYOND.

* Improve delay handling

* Bullet spread

* Fix firing guns on pickup

Content.Client/GameObjects/EntitySystems/RangedWeaponSystem.cs

@@ -0,0 +1,76 @@
+using Content.Client.GameObjects.Components.Weapons.Ranged;
+using Content.Client.Interfaces.GameObjects;
+using Content.Shared.Input;
+using SS14.Client.GameObjects.EntitySystems;
+using SS14.Client.Interfaces.Graphics.ClientEye;
+using SS14.Client.Interfaces.Input;
+using SS14.Client.Player;
+using SS14.Shared.GameObjects.Systems;
+using SS14.Shared.Input;
+using SS14.Shared.IoC;
+
+namespace Content.Client.GameObjects.EntitySystems
+{
+    public class RangedWeaponSystem : EntitySystem
+    {
+
+#pragma warning disable 649
+        [Dependency] private readonly IPlayerManager _playerManager;
+        [Dependency] private readonly IEyeManager _eyeManager;
+        [Dependency] private readonly IInputManager _inputManager;
+#pragma warning restore 649
+
+        private InputSystem _inputSystem;
+        private bool _isFirstShot;
+        private bool _blocked;
+
+        public override void Initialize()
+        {
+            base.Initialize();
+
+            IoCManager.InjectDependencies(this);
+            _inputSystem = EntitySystemManager.GetEntitySystem<InputSystem>();
+        }
+
+        public override void Update(float frameTime)
+        {
+            base.Update(frameTime);
+
+            var canFireSemi = _isFirstShot;
+            var state = _inputSystem.CmdStates.GetState(ContentKeyFunctions.UseItemInHand);
+            if (state != BoundKeyState.Down)
+            {
+                _isFirstShot = true;
+                _blocked = false;
+                return;
+            }
+
+            _isFirstShot = false;
+
+            var entity = _playerManager.LocalPlayer.ControlledEntity;
+            if (entity == null || !entity.TryGetComponent(out IHandsComponent hands))
+            {
+                return;
+            }
+
+            var held = hands.ActiveHand;
+            if (held == null || !held.TryGetComponent(out ClientRangedWeaponComponent weapon))
+            {
+                _blocked = true;
+                return;
+            }
+
+            if (_blocked)
+            {
+                return;
+            }
+
+            var worldPos = _eyeManager.ScreenToWorld(_inputManager.MouseScreenPosition);
+
+            if (weapon.Automatic || canFireSemi)
+            {
+                weapon.TryFire(worldPos);
+            }
+        }
+    }
+}