tbd-station-14/Content.Server/Nutrition/EntitySystems/SliceableFoodSystem.cs

using Content.Server.Chemistry.Components.SolutionManager;
using Content.Server.Chemistry.EntitySystems;
using Content.Server.Hands.Components;
using Content.Server.Nutrition.Components;
using Content.Shared.Chemistry.Components;
using Content.Shared.Examine;
using Content.Shared.FixedPoint;
using Content.Shared.Hands.EntitySystems;
using Content.Shared.Interaction;
using Robust.Shared.Audio;
using Robust.Shared.Containers;
using Robust.Shared.Player;

namespace Content.Server.Nutrition.EntitySystems
{
    internal sealed class SliceableFoodSystem : EntitySystem
    {
        [Dependency] private readonly SolutionContainerSystem _solutionContainerSystem = default!;
        [Dependency] private readonly SharedHandsSystem _handsSystem = default!;
        [Dependency] private readonly SharedContainerSystem _containerSystem = default!;

        public override void Initialize()
        {
            base.Initialize();

            SubscribeLocalEvent<SliceableFoodComponent, ExaminedEvent>(OnExamined);
            SubscribeLocalEvent<SliceableFoodComponent, InteractUsingEvent>(OnInteractUsing);
            SubscribeLocalEvent<SliceableFoodComponent, ComponentStartup>(OnComponentStartup);
        }

        private void OnInteractUsing(EntityUid uid, SliceableFoodComponent component, InteractUsingEvent args)
        {
            if (args.Handled)
                return;

            if (TrySliceFood(uid, args.User, args.Used, component))
                args.Handled = true;
        }

        private bool TrySliceFood(EntityUid uid, EntityUid user, EntityUid usedItem,
            SliceableFoodComponent? component = null, FoodComponent? food = null, TransformComponent? transform = null)
        {
            if (!Resolve(uid, ref component, ref food, ref transform) ||
                string.IsNullOrEmpty(component.Slice))
            {
                return false;
            }

            if (!_solutionContainerSystem.TryGetSolution(uid, food.SolutionName, out var solution))
            {
                return false;
            }

            if (!EntityManager.TryGetComponent(usedItem, out UtensilComponent ? utensil) || (utensil.Types & UtensilType.Knife) == 0)
            {
                return false;
            }

            var sliceUid = EntityManager.SpawnEntity(component.Slice, transform.Coordinates);

            var lostSolution = _solutionContainerSystem.SplitSolution(uid, solution,
                solution.CurrentVolume / FixedPoint2.New(component.Count));

            // Fill new slice
            FillSlice(sliceUid, lostSolution);

            if (EntityManager.TryGetComponent(user, out HandsComponent? handsComponent))
            {
                if (_containerSystem.IsEntityInContainer(component.Owner))
                {
                    _handsSystem.PickupOrDrop(user, sliceUid, handsComp: handsComponent);
                }
            }

            SoundSystem.Play(Filter.Pvs(uid), component.Sound.GetSound(), transform.Coordinates,
                AudioParams.Default.WithVolume(-2));

            component.Count--;
            // If someone makes food proto with 1 slice...
            if (component.Count < 1)
            {
                EntityManager.DeleteEntity(uid);
                return true;
            }

            // Split last slice
            if (component.Count == 1) {
                var lastSlice = EntityManager.SpawnEntity(component.Slice, transform.Coordinates);

                // Fill last slice with the rest of the solution
                FillSlice(lastSlice, solution);

                EntityManager.DeleteEntity(uid);
            }

            return true;
        }

        private void FillSlice(EntityUid sliceUid, Solution solution)
        {
            // Replace all reagents on prototype not just copying poisons (example: slices of eaten pizza should have less nutrition)
            if (EntityManager.TryGetComponent<FoodComponent>(sliceUid, out var sliceFoodComp) &&
                _solutionContainerSystem.TryGetSolution(sliceUid, sliceFoodComp.SolutionName, out var itsSolution))
            {
                _solutionContainerSystem.RemoveAllSolution(sliceUid, itsSolution);

                var lostSolutionPart = solution.SplitSolution(itsSolution.AvailableVolume);
                _solutionContainerSystem.TryAddSolution(sliceUid, itsSolution, lostSolutionPart);
            }
        }

        private void OnComponentStartup(EntityUid uid, SliceableFoodComponent component, ComponentStartup args)
        {
            component.Count = component.TotalCount;
            var foodComp = EntityManager.EnsureComponent<FoodComponent>(uid);

            EntityManager.EnsureComponent<SolutionContainerManagerComponent>(uid);
            _solutionContainerSystem.EnsureSolution(uid, foodComp.SolutionName);
        }

        private void OnExamined(EntityUid uid, SliceableFoodComponent component, ExaminedEvent args)
        {
            args.PushMarkup(Loc.GetString("sliceable-food-component-on-examine-remaining-slices-text", ("remainingCount", component.Count)));
        }
    }
}