Firestarter fixes (#24647)

* Firestarter fixes

- Actually networks the action.
- Namespace fixes.

* No networky for you

Content.Server/Atmos/EntitySystems/FirestarterSystem.cs

@@ -0,0 +1,62 @@
+using Content.Server.Atmos.Components;
+using Content.Shared.Actions.Events;
+using Content.Shared.Atmos.Components;
+using Content.Shared.Atmos.EntitySystems;
+using Robust.Shared.Audio.Systems;
+using Robust.Shared.Containers;
+using Robust.Shared.Map;
+
+namespace Content.Server.Atmos.EntitySystems;
+
+/// <summary>
+/// Adds an action ability that will cause all flammable targets in a radius to ignite, also heals the owner
+/// of the component when used.
+/// </summary>
+public sealed class FirestarterSystem : SharedFirestarterSystem
+{
+    [Dependency] private readonly EntityLookupSystem _lookup = default!;
+    [Dependency] private readonly FlammableSystem _flammable = default!;
+    [Dependency] private readonly SharedAudioSystem _audio = default!;
+    [Dependency] private readonly SharedContainerSystem _container = default!;
+
+    private readonly HashSet<Entity<FlammableComponent>> _flammables = new();
+
+    public override void Initialize()
+    {
+        base.Initialize();
+        SubscribeLocalEvent<FirestarterComponent, FireStarterActionEvent>(OnStartFire);
+    }
+
+    /// <summary>
+    /// Checks Radius for igniting nearby flammable objects
+    /// </summary>
+    private void OnStartFire(EntityUid uid, FirestarterComponent component, FireStarterActionEvent args)
+    {
+        if (_container.IsEntityOrParentInContainer(uid))
+            return;
+
+        var xform = Transform(uid);
+        var ignitionRadius = component.IgnitionRadius;
+        IgniteNearby(uid, xform.Coordinates, args.Severity, ignitionRadius);
+        _audio.PlayPvs(component.IgniteSound, uid);
+
+        args.Handled = true;
+    }
+
+    /// <summary>
+    /// Ignites flammable objects within range.
+    /// </summary>
+    public void IgniteNearby(EntityUid uid, EntityCoordinates coordinates, float severity, float radius)
+    {
+        _flammables.Clear();
+        _lookup.GetEntitiesInRange(coordinates, radius, _flammables);
+
+        foreach (var flammable in _flammables)
+        {
+            var ent = flammable.Owner;
+            var stackAmount = 2 + (int) (severity / 0.15f);
+            _flammable.AdjustFireStacks(ent, stackAmount, flammable);
+            _flammable.Ignite(ent, uid, flammable);
+        }
+    }
+}