tbd-station-14/Content.Server/Weapon/Ranged/Ammunition/Components/RangedMagazineComponent.cs

using System;
using System.Collections.Generic;
using System.Threading.Tasks;
using Content.Server.Hands.Components;
using Content.Server.Items;
using Content.Server.Weapon.Ranged.Barrels.Components;
using Content.Shared.Examine;
using Content.Shared.Interaction;
using Content.Shared.Popups;
using Content.Shared.Weapons.Ranged.Barrels.Components;
using Robust.Shared.Containers;
using Robust.Shared.GameObjects;
using Robust.Shared.IoC;
using Robust.Shared.Localization;
using Robust.Shared.Serialization.Manager.Attributes;
using Robust.Shared.Utility;

namespace Content.Server.Weapon.Ranged.Ammunition.Components
{
    [RegisterComponent]
#pragma warning disable 618
    public class RangedMagazineComponent : Component, IMapInit, IInteractUsing, IUse, IExamine
#pragma warning restore 618
    {
        [Dependency] private readonly IEntityManager _entities = default!;

        public override string Name => "RangedMagazine";

        private readonly Stack<EntityUid> _spawnedAmmo = new();
        private Container _ammoContainer = default!;

        public int ShotsLeft => _spawnedAmmo.Count + _unspawnedCount;
        public int Capacity => _capacity;
        [DataField("capacity")]
        private int _capacity = 20;

        public MagazineType MagazineType => _magazineType;
        [DataField("magazineType")]
        private MagazineType _magazineType = MagazineType.Unspecified;
        public BallisticCaliber Caliber => _caliber;
        [DataField("caliber")]
        private BallisticCaliber _caliber = BallisticCaliber.Unspecified;

        private AppearanceComponent? _appearanceComponent;

        // If there's anything already in the magazine
        [DataField("fillPrototype")]
        private string? _fillPrototype;

        // By default the magazine won't spawn the entity until needed so we need to keep track of how many left we can spawn
        // Generally you probablt don't want to use this
        private int _unspawnedCount;

        void IMapInit.MapInit()
        {
            if (_fillPrototype != null)
            {
                _unspawnedCount += Capacity;
            }
            UpdateAppearance();
        }

        protected override void Initialize()
        {
            base.Initialize();
            _ammoContainer = ContainerHelpers.EnsureContainer<Container>(Owner, $"{Name}-magazine", out var existing);

            if (existing)
            {
                if (_ammoContainer.ContainedEntities.Count > Capacity)
                {
                    throw new InvalidOperationException("Initialized capacity of magazine higher than its actual capacity");
                }

                foreach (var entity in _ammoContainer.ContainedEntities)
                {
                    _spawnedAmmo.Push(entity);
                    _unspawnedCount--;
                }
            }

            if (_entities.TryGetComponent(Owner, out AppearanceComponent? appearanceComponent))
            {
                _appearanceComponent = appearanceComponent;
            }

            _appearanceComponent?.SetData(MagazineBarrelVisuals.MagLoaded, true);
        }

        private void UpdateAppearance()
        {
            _appearanceComponent?.SetData(AmmoVisuals.AmmoCount, ShotsLeft);
            _appearanceComponent?.SetData(AmmoVisuals.AmmoMax, Capacity);
        }

        public bool TryInsertAmmo(EntityUid user, EntityUid ammo)
        {
            if (!_entities.TryGetComponent(ammo, out AmmoComponent? ammoComponent))
            {
                return false;
            }

            if (ammoComponent.Caliber != _caliber)
            {
                Owner.PopupMessage(user, Loc.GetString("ranged-magazine-component-try-insert-ammo-wrong-caliber"));
                return false;
            }

            if (ShotsLeft >= Capacity)
            {
                Owner.PopupMessage(user, Loc.GetString("ranged-magazine-component-try-insert-ammo-is-full "));
                return false;
            }

            _ammoContainer.Insert(ammo);
            _spawnedAmmo.Push(ammo);
            UpdateAppearance();
            return true;
        }

        public EntityUid? TakeAmmo()
        {
            EntityUid? ammo = null;
            // If anything's spawned use that first, otherwise use the fill prototype as a fallback (if we have spawn count left)
            if (_spawnedAmmo.TryPop(out var entity))
            {
                ammo = entity;
                _ammoContainer.Remove(entity);
            }
            else if (_unspawnedCount > 0)
            {
                _unspawnedCount--;
                ammo = _entities.SpawnEntity(_fillPrototype, _entities.GetComponent<TransformComponent>(Owner).Coordinates);
            }

            UpdateAppearance();
            return ammo;
        }

        async Task<bool> IInteractUsing.InteractUsing(InteractUsingEventArgs eventArgs)
        {
            return TryInsertAmmo(eventArgs.User, eventArgs.Using);
        }

        bool IUse.UseEntity(UseEntityEventArgs eventArgs)
        {
            if (!_entities.TryGetComponent(eventArgs.User, out HandsComponent? handsComponent))
            {
                return false;
            }

            if (TakeAmmo() is not {Valid: true} ammo)
            {
                return false;
            }

            var itemComponent = _entities.GetComponent<ItemComponent>(ammo);
            if (!handsComponent.CanPutInHand(itemComponent))
            {
                _entities.GetComponent<TransformComponent>(ammo).Coordinates = _entities.GetComponent<TransformComponent>(eventArgs.User).Coordinates;
                ServerRangedBarrelComponent.EjectCasing(ammo);
            }
            else
            {
                handsComponent.PutInHand(itemComponent);
            }

            return true;
        }

        public void Examine(FormattedMessage message, bool inDetailsRange)
        {
            var text = Loc.GetString("ranged-magazine-component-on-examine", ("magazineType", MagazineType),("caliber", Caliber));
            message.AddMarkup(text);
        }
    }
}