#nullable enable
using Content.Server.GameObjects.Components.Mobs;
using Content.Server.GameObjects.Components.Observer;
using Content.Shared.GameObjects.Components.Body;
using Content.Shared.GameObjects.Components.Body.Part;
using Content.Shared.GameObjects.Components.Movement;
using Robust.Shared.GameObjects;
using Robust.Shared.Interfaces.GameObjects;

namespace Content.Server.GameObjects.Components.Body.Behavior
{
    public class BrainBehavior : MechanismBehavior
    {
        protected override void OnAddedToBody(IBody body)
        {
            base.OnAddedToBody(body);

            HandleMind(body.Owner, Owner);
        }

        protected override void OnAddedToPart(IBodyPart part)
        {
            base.OnAddedToPart(part);

            HandleMind(part.Owner, Owner);
        }

        protected override void OnAddedToPartInBody(IBody body, IBodyPart part)
        {
            base.OnAddedToPartInBody(body, part);

            HandleMind(body.Owner, Owner);
        }

        protected override void OnRemovedFromBody(IBody old)
        {
            base.OnRemovedFromBody(old);

            HandleMind(Part!.Owner, old.Owner);
        }

        protected override void OnRemovedFromPart(IBodyPart old)
        {
            base.OnRemovedFromPart(old);

            HandleMind(Owner, old.Owner);
        }

        protected override void OnRemovedFromPartInBody(IBody oldBody, IBodyPart oldPart)
        {
            base.OnRemovedFromPartInBody(oldBody, oldPart);

            HandleMind(oldBody.Owner, Owner);
        }

        private void HandleMind(IEntity newEntity, IEntity oldEntity)
        {
            newEntity.EnsureComponent<MindComponent>();
            var oldMind = oldEntity.EnsureComponent<MindComponent>();

            if (!newEntity.HasComponent<IGhostOnMove>())
                newEntity.AddComponent<GhostOnMoveComponent>();

            // TODO: This is an awful solution.
            if (!newEntity.HasComponent<IMoverComponent>())
                newEntity.AddComponent<SharedDummyInputMoverComponent>();

            oldMind.Mind?.TransferTo(newEntity);
        }
    }
}