NPC refactor (#10122)

Co-authored-by: metalgearsloth <metalgearsloth@gmail.com>

Content.Server/NPC/Systems/NPCCombatSystem.Melee.cs

@@ -0,0 +1,89 @@
+using Content.Server.CombatMode;
+using Content.Server.NPC.Components;
+using Content.Server.Weapon.Melee.Components;
+using Content.Shared.MobState;
+using Content.Shared.MobState.Components;
+
+namespace Content.Server.NPC.Systems;
+
+public sealed partial class NPCCombatSystem
+{
+    private void InitializeMelee()
+    {
+        SubscribeLocalEvent<NPCMeleeCombatComponent, ComponentStartup>(OnMeleeStartup);
+        SubscribeLocalEvent<NPCMeleeCombatComponent, ComponentShutdown>(OnMeleeShutdown);
+    }
+
+    private void OnMeleeShutdown(EntityUid uid, NPCMeleeCombatComponent component, ComponentShutdown args)
+    {
+        if (TryComp<CombatModeComponent>(uid, out var combatMode))
+        {
+            combatMode.IsInCombatMode = false;
+        }
+    }
+
+    private void OnMeleeStartup(EntityUid uid, NPCMeleeCombatComponent component, ComponentStartup args)
+    {
+        if (TryComp<CombatModeComponent>(uid, out var combatMode))
+        {
+            combatMode.IsInCombatMode = true;
+        }
+
+        // TODO: Cleanup later, just looking for parity for now.
+        component.Weapon = uid;
+    }
+
+    private void UpdateMelee(float frameTime)
+    {
+        var combatQuery = GetEntityQuery<CombatModeComponent>();
+        var xformQuery = GetEntityQuery<TransformComponent>();
+
+        foreach (var (comp, _) in EntityQuery<NPCMeleeCombatComponent, ActiveNPCComponent>())
+        {
+            if (!combatQuery.TryGetComponent(comp.Owner, out var combat) || !combat.IsInCombatMode)
+            {
+                RemComp<NPCMeleeCombatComponent>(comp.Owner);
+                continue;
+            }
+
+            Attack(comp, xformQuery);
+        }
+    }
+
+    private void Attack(NPCMeleeCombatComponent component, EntityQuery<TransformComponent> xformQuery)
+    {
+        component.Status = CombatStatus.Normal;
+
+        // TODO: Also need to co-ordinate with steering to keep in range.
+        // For now I've just moved the utlity version over.
+        // Also need some blackboard data for stuff like juke frequency, assigning target slots (to surround targets), etc.
+        // miss %
+        if (!TryComp<MeleeWeaponComponent>(component.Weapon, out var weapon))
+        {
+            component.Status = CombatStatus.NoWeapon;
+            return;
+        }
+
+        if (weapon.CooldownEnd > _timing.CurTime)
+        {
+            return;
+        }
+
+        if (!xformQuery.TryGetComponent(component.Owner, out var xform) ||
+            !xformQuery.TryGetComponent(component.Target, out var targetXform))
+        {
+            component.Status = CombatStatus.TargetUnreachable;
+            return;
+        }
+
+        if (!xform.Coordinates.TryDistance(EntityManager, targetXform.Coordinates, out var distance) ||
+            distance > weapon.Range)
+        {
+            // TODO: Steering in combat.
+            component.Status = CombatStatus.TargetUnreachable;
+            return;
+        }
+
+        _interaction.DoAttack(component.Owner, targetXform.Coordinates, false, component.Target);
+    }
+}