Objectives ecs rework (#19967)

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

Content.Server/Objectives/Systems/TargetObjectiveSystem.cs

@@ -0,0 +1,68 @@
+using Content.Server.Objectives.Components;
+using Content.Shared.Mind;
+using Content.Shared.Objectives.Components;
+using Content.Shared.Roles.Jobs;
+using Robust.Shared.GameObjects;
+using System.Diagnostics.CodeAnalysis;
+
+namespace Content.Server.Objectives.Systems;
+
+/// <summary>
+/// Provides API for other components and handles setting the title.
+/// </summary>
+public sealed class TargetObjectiveSystem : EntitySystem
+{
+    [Dependency] private readonly MetaDataSystem _metaData = default!;
+    [Dependency] private readonly SharedJobSystem _job = default!;
+
+    public override void Initialize()
+    {
+        base.Initialize();
+
+        SubscribeLocalEvent<TargetObjectiveComponent, ObjectiveAfterAssignEvent>(OnAfterAssign);
+    }
+
+    private void OnAfterAssign(EntityUid uid, TargetObjectiveComponent comp, ref ObjectiveAfterAssignEvent args)
+    {
+        if (!GetTarget(uid, out var target, comp))
+            return;
+
+        _metaData.SetEntityName(uid, GetTitle(target.Value, comp.Title), args.Meta);
+    }
+
+    /// <summary>
+    /// Sets the Target field for the title and other components to use.
+    /// </summary>
+    public void SetTarget(EntityUid uid, EntityUid target, TargetObjectiveComponent? comp = null)
+    {
+        if (!Resolve(uid, ref comp))
+            return;
+
+        comp.Target = target;
+    }
+
+    /// <summary>
+    /// Gets the target from the component.
+    /// </summary>
+    /// <remarks>
+    /// If it is null then the prototype is invalid, just return.
+    /// </remarks>
+    public bool GetTarget(EntityUid uid, [NotNullWhen(true)] out EntityUid? target, TargetObjectiveComponent? comp = null)
+    {
+        target = Resolve(uid, ref comp) ? comp.Target : null;
+        return target != null;
+    }
+
+    private string GetTitle(EntityUid target, string title)
+    {
+        var targetName = "Unknown";
+        if (TryComp<MindComponent>(target, out var mind) && mind.CharacterName != null)
+        {
+            targetName = mind.CharacterName;
+        }
+
+        var jobName = _job.MindTryGetJobName(target);
+        return Loc.GetString(title, ("targetName", targetName), ("job", jobName));
+    }
+
+}