Add syndicate sleeper agents random event

Content.Server/AlertLevel/AlertLevelSystem.cs

@@ -96,6 +96,16 @@ private void OnPrototypeReload(PrototypesReloadedEventArgs args)
         RaiseLocalEvent(new AlertLevelPrototypeReloadedEvent());
     }
 
+    public string GetLevel(EntityUid station, AlertLevelComponent? alert = null)
+    {
+        if (!Resolve(station, ref alert))
+        {
+            return string.Empty;
+        }
+
+        return alert.CurrentLevel;
+    }
+
     public float GetAlertLevelDelay(EntityUid station, AlertLevelComponent? alert = null)
     {
         if (!Resolve(station, ref alert))

Content.Server/StationEvents/Components/AlertLevelInterceptionRuleComponent.cs

@@ -0,0 +1,15 @@
+using Content.Server.StationEvents.Events;
+using Content.Server.AlertLevel;
+using Robust.Shared.Prototypes;
+
+namespace Content.Server.StationEvents.Components;
+
+[RegisterComponent, Access(typeof(AlertLevelInterceptionRule))]
+public sealed partial class AlertLevelInterceptionRuleComponent : Component
+{
+    /// <summary>
+    /// Alert level to set the station to when the event starts.
+    /// </summary>
+    [DataField]
+    public string AlertLevel = "blue";
+}

Content.Server/StationEvents/Events/AlertLevelInterceptionRule.cs

@@ -0,0 +1,23 @@
+using Content.Server.GameTicking.Components;
+using Content.Server.StationEvents.Components;
+using Content.Server.AlertLevel;
+
+namespace Content.Server.StationEvents.Events;
+
+public sealed class AlertLevelInterceptionRule : StationEventSystem<AlertLevelInterceptionRuleComponent>
+{
+    [Dependency] private readonly AlertLevelSystem _alertLevelSystem = default!;
+
+    protected override void Started(EntityUid uid, AlertLevelInterceptionRuleComponent component, GameRuleComponent gameRule,
+        GameRuleStartedEvent args)
+    {
+        base.Started(uid, component, gameRule, args);
+
+        if (!TryGetRandomStation(out var chosenStation))
+            return;
+        if (_alertLevelSystem.GetLevel(chosenStation.Value) != "green")
+            return;
+
+        _alertLevelSystem.SetLevel(chosenStation.Value, component.AlertLevel, true, true, true);
+    }
+}

Resources/Audio/Announcements/attributions.yml

@@ -42,3 +42,8 @@
   license: "CC-BY-SA-3.0"
   copyright: "Paradise, volume and pitch changed, merged with redalert.ogg"
   source: "https://github.com/ParadiseSS13/Paradise/blob/07b26ee6b4a11a0607986d322ee007020569feae/sound/effects/siren.ogg"
+
+- files: ["intercept.ogg"]
+  license: "CC-BY-SA-3.0"
+  copyright: "Taken from tgstation"
+  source: "https://github.com/tgstation/tgstation/blob/95731342b97167d7883ff091d389f79c36442ee6/sound/ai/default/intercept.ogg"

Resources/Locale/en-US/station-events/events/intercept.ftl

@@ -0,0 +1 @@
+station-event-communication-interception = Attention! Enemy communication intercepted. Security level elevated.

Resources/Prototypes/GameRules/events.yml

@@ -454,6 +454,31 @@
       - type: NukeopsRole
         prototype: Nukeops
 
+- type: entity
+  id: SleeperAgentsRule
+  parent: BaseGameRule
+  noSpawn: true
+  components:
+  - type: StationEvent
+    earliestStart: 25
+    weight: 15
+    minimumPlayers: 15
+    reoccurrenceDelay: 60
+    startAnnouncement: station-event-communication-interception
+    startAudio:
+      path: /Audio/Announcements/intercept.ogg
+  - type: AlertLevelInterceptionRule
+  - type: TraitorRule
+  - type: AntagSelection
+    definitions:
+    - prefRoles: [ Traitor ]
+      min: 1
+      max: 2
+      playerRatio: 10
+      mindComponents:
+      - type: TraitorRole
+        prototype: Traitor
+
 - type: entity
   id: MassHallucinations
   parent: BaseGameRule