Feat: Port Delta-V Glimmer Wisps (#1125)

# Description
Ports DeltaV-Station/Delta-v#1383 with all due
changes.

Also moves some files from delta-v/nyano namespaces to the root
namespace.

# TODO
- [X] Port fun
- [X] Test fun
- [X] Record fun

<details><summary><h1>Media</h1></summary>
<p>

I had to compress the shit out of this video, so it's about as good as
it can get.


https://github.com/user-attachments/assets/3ab9d328-ae6e-4a6c-8a48-9da22783579a

</p>
</details>

---

# Changelog
:cl:
- add: Raising glimmer too high can now cause glimmer wisps to start
haunting the station.

---------

Co-authored-by: deltanedas <[email protected]>

Content.Server/LifeDrainer/LifeDrainerComponent.cs

@@ -0,0 +1,60 @@
+using Content.Shared.Damage;
+using Content.Shared.DoAfter;
+using Content.Shared.Whitelist;
+using Robust.Shared.Audio;
+
+namespace Content.Server.LifeDrainer;
+
+/// <summary>
+/// Adds a verb to drain life from a crit mob that matches a whitelist.
+/// Successfully draining a mob rejuvenates you completely.
+/// </summary>
+[RegisterComponent, Access(typeof(LifeDrainerSystem))]
+public sealed partial class LifeDrainerComponent : Component
+{
+    /// <summary>
+    /// Damage to give to the target when draining is complete
+    /// </summary>
+    [DataField(required: true)]
+    public DamageSpecifier Damage = new();
+
+    /// <summary>
+    /// Mobs have to match this whitelist to be drained.
+    /// </summary>
+    [DataField]
+    public EntityWhitelist? Whitelist;
+
+    /// <summary>
+    /// The time that it takes to drain an entity.
+    /// </summary>
+    [DataField]
+    public TimeSpan Delay = TimeSpan.FromSeconds(8.35f);
+
+    /// <summary>
+    /// Sound played while draining a mob.
+    /// </summary>
+    [DataField]
+    public SoundSpecifier DrainSound = new SoundPathSpecifier("/Audio/DeltaV/Effects/clang2.ogg");
+
+    /// <summary>
+    /// Sound played after draining is complete.
+    /// </summary>
+    [DataField]
+    public SoundSpecifier FinishSound = new SoundPathSpecifier("/Audio/Effects/guardian_inject.ogg");
+
+    [DataField]
+    public EntityUid? DrainStream;
+
+    /// <summary>
+    /// A current drain doafter in progress.
+    /// </summary>
+    [DataField]
+    public DoAfterId? DoAfter;
+
+    /// <summary>
+    /// What mob is being targeted for draining.
+    /// When draining stops the AI will try to drain this target again until successful.
+    /// </summary>
+    [DataField]
+    public EntityUid? Target;
+}

Content.Server/LifeDrainer/LifeDrainerSystem.cs

@@ -0,0 +1,143 @@
+using Content.Server.Carrying;
+using Content.Server.NPC.Systems;
+using Content.Shared.ActionBlocker;
+using Content.Shared.Damage;
+using Content.Shared.DoAfter;
+using Content.Shared.Interaction;
+using Content.Shared.Mobs.Systems;
+using Content.Shared.Movement.Pulling.Components;
+using Content.Shared.Popups;
+using Content.Shared.Rejuvenate;
+using Content.Shared.Verbs;
+using Content.Shared.Whitelist;
+using Robust.Shared.Audio.Systems;
+using Robust.Shared.Player;
+using Robust.Shared.Utility;
+
+namespace Content.Server.LifeDrainer;
+
+public sealed class LifeDrainerSystem : EntitySystem
+{
+    [Dependency] private readonly ActionBlockerSystem _actionBlocker = default!;
+    [Dependency] private readonly DamageableSystem _damageable = default!;
+    [Dependency] private readonly EntityWhitelistSystem _whitelist = default!;
+    [Dependency] private readonly MobStateSystem _mob = default!;
+    [Dependency] private readonly NpcFactionSystem _faction = default!;
+    [Dependency] private readonly SharedAudioSystem _audio = default!;
+    [Dependency] private readonly SharedDoAfterSystem _doAfter = default!;
+    [Dependency] private readonly SharedInteractionSystem _interaction = default!;
+    [Dependency] private readonly SharedPopupSystem _popup = default!;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<LifeDrainerComponent, GetVerbsEvent<InnateVerb>>(OnGetVerbs);
+        SubscribeLocalEvent<LifeDrainerComponent, LifeDrainDoAfterEvent>(OnDrain);
+    }
+
+    private void OnGetVerbs(Entity<LifeDrainerComponent> ent, ref GetVerbsEvent<InnateVerb> args)
+    {
+        var target = args.Target;
+        if (!args.CanAccess || !args.CanInteract || !CanDrain(ent, target))
+            return;
+
+        args.Verbs.Add(new InnateVerb()
+        {
+            Act = () =>
+            {
+                TryDrain(ent, target);
+            },
+            Text = Loc.GetString("verb-life-drain"),
+            Icon = new SpriteSpecifier.Texture(new ("/Textures/Nyanotrasen/Icons/verbiconfangs.png")),
+            Priority = 2
+        });
+    }
+
+    private void OnDrain(Entity<LifeDrainerComponent> ent, ref LifeDrainDoAfterEvent args)
+    {
+        var (uid, comp) = ent;
+        CancelDrain(comp);
+        if (args.Handled || args.Args.Target is not {} target)
+            return;
+
+        // attack whoever interrupted the draining
+        if (args.Cancelled)
+        {
+            // someone pulled the psionic away
+            if (TryComp<PullableComponent>(target, out var pullable) && pullable.Puller is {} puller)
+                _faction.AggroEntity(uid, puller);
+
+            // someone pulled me away
+            if (TryComp(ent, out pullable) && pullable.Puller is {} selfPuller)
+                _faction.AggroEntity(uid, selfPuller);
+
+            // someone carried the psionic away
+            if (TryComp<BeingCarriedComponent>(target, out var carried))
+                _faction.AggroEntity(uid, carried.Carrier);
+
+            return;
+        }
+
+        _popup.PopupEntity(Loc.GetString("life-drain-second-end", ("drainer", uid)), target, target, PopupType.LargeCaution);
+        _popup.PopupEntity(Loc.GetString("life-drain-third-end", ("drainer", uid), ("target", target)), target, Filter.PvsExcept(target), true, PopupType.LargeCaution);
+
+        var rejuv = new RejuvenateEvent();
+        RaiseLocalEvent(uid, rejuv);
+
+        _audio.PlayPvs(comp.FinishSound, uid);
+
+        _damageable.TryChangeDamage(target, comp.Damage, true, origin: uid);
+    }
+
+    public bool CanDrain(Entity<LifeDrainerComponent> ent, EntityUid target)
+    {
+        var (uid, comp) = ent;
+        return !IsDraining(comp)
+            && uid != target
+            && (comp.Whitelist is null || _whitelist.IsValid(comp.Whitelist, target))
+            && _mob.IsCritical(target);
+    }
+
+    public bool IsDraining(LifeDrainerComponent comp)
+    {
+        return _doAfter.GetStatus(comp.DoAfter) == DoAfterStatus.Running;
+    }
+
+    public bool TryDrain(Entity<LifeDrainerComponent> ent, EntityUid target)
+    {
+        var (uid, comp) = ent;
+        if (!CanDrain(ent, target) || !_actionBlocker.CanInteract(uid, target) || !_interaction.InRangeUnobstructed(ent, target, popup: true))
+            return false;
+
+        _popup.PopupEntity(Loc.GetString("life-drain-second-start", ("drainer", uid)), target, target, PopupType.LargeCaution);
+        _popup.PopupEntity(Loc.GetString("life-drain-third-start", ("drainer", uid), ("target", target)), target, Filter.PvsExcept(target), true, PopupType.LargeCaution);
+
+        if (_audio.PlayPvs(comp.DrainSound, target) is {} stream)
+            comp.DrainStream = stream.Item1;
+
+        var ev = new LifeDrainDoAfterEvent();
+        var args = new DoAfterArgs(EntityManager, uid, comp.Delay, ev, target: target, eventTarget: uid)
+        {
+            BreakOnTargetMove = true,
+            BreakOnUserMove = true,
+            MovementThreshold = 2f,
+            NeedHand = false
+        };
+
+        if (!_doAfter.TryStartDoAfter(args, out var id))
+            return false;
+
+        comp.DoAfter = id;
+        comp.Target = target;
+        return true;
+    }
+
+    public void CancelDrain(LifeDrainerComponent comp)
+    {
+        comp.DrainStream = _audio.Stop(comp.DrainStream);
+        _doAfter.Cancel(comp.DoAfter);
+        comp.DoAfter = null;
+        comp.Target = null;
+    }
+}

Content.Server/NPC/HTN/PrimitiveTasks/Operators/Interactions/DrainOperator.cs

@@ -0,0 +1,50 @@
+using Content.Server.LifeDrainer;
+
+namespace Content.Server.NPC.HTN.PrimitiveTasks.Operators.Interactions;
+
+public sealed partial class DrainOperator : HTNOperator
+{
+    [Dependency] private readonly IEntityManager _entMan = default!;
+
+    private LifeDrainerSystem _drainer = default!;
+    private EntityQuery<LifeDrainerComponent> _drainerQuery;
+
+    [DataField(required: true)]
+    public string DrainKey = string.Empty;
+
+    public override void Initialize(IEntitySystemManager sysManager)
+    {
+        base.Initialize(sysManager);
+
+        _drainer = sysManager.GetEntitySystem<LifeDrainerSystem>();
+        _drainerQuery = _entMan.GetEntityQuery<LifeDrainerComponent>();
+    }
+
+    public override HTNOperatorStatus Update(NPCBlackboard blackboard, float frameTime)
+    {
+        var owner = blackboard.GetValue<EntityUid>(NPCBlackboard.Owner);
+        var target = blackboard.GetValue<EntityUid>(DrainKey);
+
+        if (_entMan.Deleted(target))
+            return HTNOperatorStatus.Failed;
+
+        if (!_drainerQuery.TryComp(owner, out var wisp))
+            return HTNOperatorStatus.Failed;
+
+        // still draining hold your horses
+        if (_drainer.IsDraining(wisp))
+            return HTNOperatorStatus.Continuing;
+
+        // not draining and no target set, start to drain
+        if (wisp.Target == null)
+        {
+            return _drainer.TryDrain((owner, wisp), target)
+                ? HTNOperatorStatus.Continuing
+                : HTNOperatorStatus.Failed;
+        }
+
+        // stopped draining, clean up and find another one after
+        _drainer.CancelDrain(wisp);
+        return HTNOperatorStatus.Finished;
+    }
+}