Move entity effects definitions to shared (#35614)

* Move entity effects to shared

* relocate spawning to server

* Generic version of EntityEffect for just raising event.

* genericise everything

* oops forgot to push you

* some condensation

* finish rebas

* unwhite the space

* oops forgot nuke

* bad rebase fix

* useless annotations begone

---------

Co-authored-by: EmoGarbage404 <retron404@gmail.com>

Content.Shared/EntityEffects/Effects/MovespeedModifier.cs

@@ -0,0 +1,78 @@
+using Content.Shared.Chemistry.Components;
+using Content.Shared.Movement.Systems;
+using Robust.Shared.Prototypes;
+using Robust.Shared.Timing;
+
+namespace Content.Shared.EntityEffects.Effects;
+
+/// <summary>
+/// Default metabolism for stimulants and tranqs. Attempts to find a MovementSpeedModifier on the target,
+/// adding one if not there and to change the movespeed
+/// </summary>
+public sealed partial class MovespeedModifier : EntityEffect
+{
+    /// <summary>
+    /// How much the entities' walk speed is multiplied by.
+    /// </summary>
+    [DataField]
+    public float WalkSpeedModifier { get; set; } = 1;
+
+    /// <summary>
+    /// How much the entities' run speed is multiplied by.
+    /// </summary>
+    [DataField]
+    public float SprintSpeedModifier { get; set; } = 1;
+
+    /// <summary>
+    /// How long the modifier applies (in seconds).
+    /// Is scaled by reagent amount if used with an EntityEffectReagentArgs.
+    /// </summary>
+    [DataField]
+    public float StatusLifetime = 2f;
+
+    protected override string? ReagentEffectGuidebookText(IPrototypeManager prototype, IEntitySystemManager entSys)
+    {
+        return Loc.GetString("reagent-effect-guidebook-movespeed-modifier",
+            ("chance", Probability),
+            ("walkspeed", WalkSpeedModifier),
+            ("time", StatusLifetime));
+    }
+
+    /// <summary>
+    /// Remove reagent at set rate, changes the movespeed modifiers and adds a MovespeedModifierMetabolismComponent if not already there.
+    /// </summary>
+    public override void Effect(EntityEffectBaseArgs args)
+    {
+        var status = args.EntityManager.EnsureComponent<MovespeedModifierMetabolismComponent>(args.TargetEntity);
+
+        // Only refresh movement if we need to.
+        var modified = !status.WalkSpeedModifier.Equals(WalkSpeedModifier) ||
+                       !status.SprintSpeedModifier.Equals(SprintSpeedModifier);
+
+        status.WalkSpeedModifier = WalkSpeedModifier;
+        status.SprintSpeedModifier = SprintSpeedModifier;
+
+        // only going to scale application time
+        var statusLifetime = StatusLifetime;
+
+        if (args is EntityEffectReagentArgs reagentArgs)
+        {
+            statusLifetime *= reagentArgs.Scale.Float();
+        }
+
+        IncreaseTimer(status, statusLifetime, args.EntityManager, args.TargetEntity);
+
+        if (modified)
+            args.EntityManager.System<MovementSpeedModifierSystem>().RefreshMovementSpeedModifiers(args.TargetEntity);
+    }
+    private void IncreaseTimer(MovespeedModifierMetabolismComponent status, float time, IEntityManager entityManager, EntityUid uid)
+    {
+        var gameTiming = IoCManager.Resolve<IGameTiming>();
+
+        var offsetTime = Math.Max(status.ModifierTimer.TotalSeconds, gameTiming.CurTime.TotalSeconds);
+
+        status.ModifierTimer = TimeSpan.FromSeconds(offsetTime + time);
+
+        entityManager.Dirty(uid, status);
+    }
+}