tbd-station-14/Content.Shared/Item/ItemToggle/ItemToggleSystem.cs

using Content.Shared.Interaction.Events;
using Content.Shared.Item.ItemToggle.Components;
using Content.Shared.Popups;
using Content.Shared.Temperature;
using Content.Shared.Toggleable;
using Content.Shared.Wieldable;
using Robust.Shared.Audio;
using Robust.Shared.Audio.Systems;
using Robust.Shared.Network;

namespace Content.Shared.Item.ItemToggle;
/// <summary>
/// Handles generic item toggles, like a welder turning on and off, or an e-sword.
/// </summary>
/// <remarks>
/// If you need extended functionality (e.g. requiring power) then add a new component and use events.
/// </remarks>
public sealed class ItemToggleSystem : EntitySystem
{
    [Dependency] private readonly INetManager _netManager = default!;
    [Dependency] private readonly SharedAppearanceSystem _appearance = default!;
    [Dependency] private readonly SharedAudioSystem _audio = default!;
    [Dependency] private readonly SharedPointLightSystem _light = default!;
    [Dependency] private readonly SharedPopupSystem _popup = default!;

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

        SubscribeLocalEvent<ItemToggleComponent, ComponentStartup>(OnStartup);
        SubscribeLocalEvent<ItemToggleComponent, MapInitEvent>(OnMapInit);
        SubscribeLocalEvent<ItemToggleComponent, ItemUnwieldedEvent>(TurnOffOnUnwielded);
        SubscribeLocalEvent<ItemToggleComponent, ItemWieldedEvent>(TurnOnOnWielded);
        SubscribeLocalEvent<ItemToggleComponent, UseInHandEvent>(OnUseInHand);

        SubscribeLocalEvent<ItemToggleHotComponent, IsHotEvent>(OnIsHotEvent);

        SubscribeLocalEvent<ItemToggleActiveSoundComponent, ItemToggledEvent>(UpdateActiveSound);
    }

    private void OnStartup(Entity<ItemToggleComponent> ent, ref ComponentStartup args)
    {
        UpdateVisuals(ent);
    }

    private void OnMapInit(Entity<ItemToggleComponent> ent, ref MapInitEvent args)
    {
        if (!ent.Comp.Activated)
            return;

        var ev = new ItemToggledEvent(Predicted: ent.Comp.Predictable, Activated: ent.Comp.Activated, User: null);
        RaiseLocalEvent(ent, ref ev);
    }

    private void OnUseInHand(Entity<ItemToggleComponent> ent, ref UseInHandEvent args)
    {
        if (args.Handled || !ent.Comp.OnUse)
            return;

        args.Handled = true;

        Toggle((ent, ent.Comp), args.User, predicted: ent.Comp.Predictable);
    }

    /// <summary>
    /// Used when an item is attempted to be toggled.
    /// Sets its state to the opposite of what it is.
    /// </summary>
    /// <returns>Same as <see cref="TrySetActive"/></returns>
    public bool Toggle(Entity<ItemToggleComponent?> ent, EntityUid? user = null, bool predicted = true)
    {
        if (!Resolve(ent, ref ent.Comp))
            return false;

        return TrySetActive(ent, !ent.Comp.Activated, user, predicted);
    }

    /// <summary>
    /// Tries to set the activated bool from a value.
    /// </summary>
    /// <returns>false if the attempt fails for any reason</returns>
    public bool TrySetActive(Entity<ItemToggleComponent?> ent, bool active, EntityUid? user = null, bool predicted = true)
    {
        if (active)
            return TryActivate(ent, user, predicted: predicted);
        else
            return TryDeactivate(ent, user, predicted: predicted);
    }

    /// <summary>
    /// Used when an item is attempting to be activated. It returns false if the attempt fails any reason, interrupting the activation.
    /// </summary>
    public bool TryActivate(Entity<ItemToggleComponent?> ent, EntityUid? user = null, bool predicted = true)
    {
        if (!Resolve(ent, ref ent.Comp))
            return false;

        var uid = ent.Owner;
        var comp = ent.Comp;
        if (comp.Activated)
            return true;

        if (!comp.Predictable && _netManager.IsClient)
            return true;

        var attempt = new ItemToggleActivateAttemptEvent(user);
        RaiseLocalEvent(uid, ref attempt);

        if (!comp.Predictable) predicted = false;
        if (attempt.Cancelled)
        {
            if (predicted)
                _audio.PlayPredicted(comp.SoundFailToActivate, uid, user);
            else
                _audio.PlayPvs(comp.SoundFailToActivate, uid);

            if (attempt.Popup != null && user != null)
            {
                if (predicted)
                    _popup.PopupClient(attempt.Popup, uid, user.Value);
                else
                    _popup.PopupEntity(attempt.Popup, uid, user.Value);
            }

            return false;
        }

        Activate((uid, comp), predicted, user);

        return true;
    }

    /// <summary>
    /// Used when an item is attempting to be deactivated. It returns false if the attempt fails any reason, interrupting the deactivation.
    /// </summary>
    public bool TryDeactivate(Entity<ItemToggleComponent?> ent, EntityUid? user = null, bool predicted = true)
    {
        if (!Resolve(ent, ref ent.Comp))
            return false;

        var uid = ent.Owner;
        var comp = ent.Comp;
        if (!comp.Activated)
            return true;

        if (!comp.Predictable && _netManager.IsClient)
            return true;

        var attempt = new ItemToggleDeactivateAttemptEvent(user);
        RaiseLocalEvent(uid, ref attempt);

        if (attempt.Cancelled)
            return false;

        if (!comp.Predictable) predicted = false;
        Deactivate((uid, comp), predicted, user);
        return true;
    }

    private void Activate(Entity<ItemToggleComponent> ent, bool predicted, EntityUid? user = null)
    {
        var (uid, comp) = ent;
        var soundToPlay = comp.SoundActivate;
        if (predicted)
            _audio.PlayPredicted(soundToPlay, uid, user);
        else
            _audio.PlayPvs(soundToPlay, uid);

        comp.Activated = true;
        UpdateVisuals((uid, comp));
        Dirty(uid, comp);

        var toggleUsed = new ItemToggledEvent(predicted, Activated: true, user);
        RaiseLocalEvent(uid, ref toggleUsed);
    }

    /// <summary>
    /// Used to make the actual changes to the item's components on deactivation.
    /// </summary>
    private void Deactivate(Entity<ItemToggleComponent> ent, bool predicted, EntityUid? user = null)
    {
        var (uid, comp) = ent;
        var soundToPlay = comp.SoundDeactivate;
        if (predicted)
            _audio.PlayPredicted(soundToPlay, uid, user);
        else
            _audio.PlayPvs(soundToPlay, uid);

        comp.Activated = false;
        UpdateVisuals((uid, comp));
        Dirty(uid, comp);

        var toggleUsed = new ItemToggledEvent(predicted, Activated: false, user);
        RaiseLocalEvent(uid, ref toggleUsed);
    }

    private void UpdateVisuals(Entity<ItemToggleComponent> ent)
    {
        if (TryComp(ent, out AppearanceComponent? appearance))
        {
            _appearance.SetData(ent, ToggleVisuals.Toggled, ent.Comp.Activated, appearance);

            if (ent.Comp.ToggleLight)
                _appearance.SetData(ent, ToggleableLightVisuals.Enabled, ent.Comp.Activated, appearance);
        }

        if (!ent.Comp.ToggleLight)
            return;

        if (_light.TryGetLight(ent, out var light))
            _light.SetEnabled(ent, ent.Comp.Activated, light);
    }

    /// <summary>
    /// Used for items that require to be wielded in both hands to activate. For instance the dual energy sword will turn off if not wielded.
    /// </summary>
    private void TurnOffOnUnwielded(Entity<ItemToggleComponent> ent, ref ItemUnwieldedEvent args)
    {
        TryDeactivate((ent, ent.Comp), args.User);
    }

    /// <summary>
    /// Wieldable items will automatically turn on when wielded.
    /// </summary>
    private void TurnOnOnWielded(Entity<ItemToggleComponent> ent, ref ItemWieldedEvent args)
    {
        // FIXME: for some reason both client and server play sound
        TryActivate((ent, ent.Comp));
    }

    public bool IsActivated(Entity<ItemToggleComponent?> ent)
    {
        if (!Resolve(ent, ref ent.Comp, false))
            return true; // assume always activated if no component

        return ent.Comp.Activated;
    }

    /// <summary>
    /// Used to make the item hot when activated.
    /// </summary>
    private void OnIsHotEvent(Entity<ItemToggleHotComponent> ent, ref IsHotEvent args)
    {
        args.IsHot |= IsActivated(ent.Owner);
    }

    /// <summary>
    /// Used to update the looping active sound linked to the entity.
    /// </summary>
    private void UpdateActiveSound(Entity<ItemToggleActiveSoundComponent> ent, ref ItemToggledEvent args)
    {
        var (uid, comp) = ent;
        if (!args.Activated)
        {
            comp.PlayingStream = _audio.Stop(comp.PlayingStream);
            return;
        }

        if (comp.ActiveSound != null && comp.PlayingStream == null)
        {
            var loop = AudioParams.Default.WithLoop(true);
            var stream = args.Predicted
                ? _audio.PlayPredicted(comp.ActiveSound, uid, args.User, loop)
                : _audio.PlayPvs(comp.ActiveSound, uid, loop);
            if (stream?.Entity is {} entity)
                comp.PlayingStream = entity;
        }
    }
}