make dragons breathe fire (#26746)

* add ActionGun system

* add RepeatingTrigger

* dragons breath projectile, repeatedly explodes

* give dragon fire breathing action, fireproof it

* oop

* oop 2

* prevent troll

* proper repeating thing

* pro

* webedit ops

* realops

---------

Co-authored-by: deltanedas <@deltanedas:kde.org>

Content.Shared/Weapons/Ranged/Components/ActionGunComponent.cs

@@ -0,0 +1,37 @@
+using Content.Shared.Actions;
+using Content.Shared.Weapons.Ranged.Systems;
+using Robust.Shared.GameStates;
+using Robust.Shared.Prototypes;
+
+namespace Content.Shared.Weapons.Ranged.Components;
+
+/// <summary>
+/// Lets you shoot a gun using an action.
+/// </summary>
+[RegisterComponent, NetworkedComponent, Access(typeof(ActionGunSystem))]
+public sealed partial class ActionGunComponent : Component
+{
+    /// <summary>
+    /// Action to create, must use <see cref="ActionGunShootEvent"/>.
+    /// </summary>
+    [DataField(required: true)]
+    public EntProtoId Action = string.Empty;
+
+    [DataField]
+    public EntityUid? ActionEntity;
+
+    /// <summary>
+    /// Prototype of gun entity to spawn.
+    /// Deleted when this component is removed.
+    /// </summary>
+    [DataField(required: true)]
+    public EntProtoId GunProto = string.Empty;
+
+    [DataField]
+    public EntityUid? Gun;
+}
+
+/// <summary>
+/// Action event for <see cref="ActionGunComponent"/> to shoot at a position.
+/// </summary>
+public sealed partial class ActionGunShootEvent : WorldTargetActionEvent;

Content.Shared/Weapons/Ranged/Systems/ActionGunSystem.cs

@@ -0,0 +1,41 @@
+using Content.Shared.Actions;
+using Content.Shared.Weapons.Ranged.Components;
+
+namespace Content.Shared.Weapons.Ranged.Systems;
+
+public sealed class ActionGunSystem : EntitySystem
+{
+    [Dependency] private readonly SharedActionsSystem _actions = default!;
+    [Dependency] private readonly SharedGunSystem _gun = default!;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<ActionGunComponent, MapInitEvent>(OnMapInit);
+        SubscribeLocalEvent<ActionGunComponent, ComponentShutdown>(OnShutdown);
+        SubscribeLocalEvent<ActionGunComponent, ActionGunShootEvent>(OnShoot);
+    }
+
+    private void OnMapInit(Entity<ActionGunComponent> ent, ref MapInitEvent args)
+    {
+        if (string.IsNullOrEmpty(ent.Comp.Action))
+            return;
+
+        _actions.AddAction(ent, ref ent.Comp.ActionEntity, ent.Comp.Action);
+        ent.Comp.Gun = Spawn(ent.Comp.GunProto);
+    }
+
+    private void OnShutdown(Entity<ActionGunComponent> ent, ref ComponentShutdown args)
+    {
+        if (ent.Comp.Gun is {} gun)
+            QueueDel(gun);
+    }
+
+    private void OnShoot(Entity<ActionGunComponent> ent, ref ActionGunShootEvent args)
+    {
+        if (TryComp<GunComponent>(ent.Comp.Gun, out var gun))
+            _gun.AttemptShoot(ent, ent.Comp.Gun.Value, gun, args.Target);
+    }
+}
+