civ14/Content.Client/Weapons/Ranged/Systems/GunSystem.cs

using System.Linq;
using System.Numerics;
using Content.Client.Animations;
using Content.Client.Gameplay;
using Content.Client.Items;
using Content.Client.Weapons.Ranged.Components;
using Content.Shared._RMC14.Weapons.Ranged.Prediction;
using Content.Shared.CombatMode;
using Content.Shared.Weapons.Ranged.Events;
using Content.Shared.Weapons.Ranged.Systems;
using Robust.Client.Animations;
using Robust.Client.GameObjects;
using Robust.Client.Graphics;
using Robust.Client.Input;
using Robust.Client.Physics;
using Robust.Client.Player;
using Robust.Client.State;
using Robust.Shared.Animations;
using Robust.Shared.Input;
using Robust.Shared.Map;
using Robust.Shared.Map.Components;
using Robust.Shared.Prototypes;
using Robust.Shared.Utility;
using SharedGunSystem = Content.Shared.Weapons.Ranged.Systems.SharedGunSystem;
using TimedDespawnComponent = Robust.Shared.Spawners.TimedDespawnComponent;

namespace Content.Client.Weapons.Ranged.Systems;

public sealed partial class GunSystem : SharedGunSystem
{
    [Dependency] private readonly IComponentFactory _factory = default!;
    [Dependency] private readonly IEyeManager _eyeManager = default!;
    [Dependency] private readonly IInputManager _inputManager = default!;
    [Dependency] private readonly IPlayerManager _player = default!;
    [Dependency] private readonly IStateManager _state = default!;
    [Dependency] private readonly AnimationPlayerSystem _animPlayer = default!;
    [Dependency] private readonly InputSystem _inputSystem = default!;
    [Dependency] private readonly SharedMapSystem _maps = default!;
    [Dependency] private readonly PhysicsSystem _physics = default!;

    [ValidatePrototypeId<EntityPrototype>]
    public const string HitscanProto = "HitscanEffect";

    public bool SpreadOverlay
    {
        get => _spreadOverlay;
        set
        {
            if (_spreadOverlay == value)
                return;

            _spreadOverlay = value;
            var overlayManager = IoCManager.Resolve<IOverlayManager>();

            if (_spreadOverlay)
            {
                overlayManager.AddOverlay(new GunSpreadOverlay(
                    EntityManager,
                    _eyeManager,
                    Timing,
                    _inputManager,
                    _player,
                    this,
                    TransformSystem));
            }
            else
            {
                overlayManager.RemoveOverlay<GunSpreadOverlay>();
            }
        }
    }

    private bool _spreadOverlay;

    public override void Initialize()
    {
        base.Initialize();
        UpdatesOutsidePrediction = true;
        SubscribeLocalEvent<AmmoCounterComponent, ItemStatusCollectMessage>(OnAmmoCounterCollect);
        SubscribeAllEvent<MuzzleFlashEvent>(OnMuzzleFlash);

        // Plays animated effects on the client.
        SubscribeNetworkEvent<HitscanEvent>(OnHitscan);

        InitializeMagazineVisuals();
        InitializeSpentAmmo();
    }

    private void OnMuzzleFlash(MuzzleFlashEvent args)
    {
        var gunUid = GetEntity(args.Uid);

        CreateEffect(gunUid, args, gunUid, _player.LocalEntity);
    }

    private void OnHitscan(HitscanEvent ev)
    {
        // ALL I WANT IS AN ANIMATED EFFECT
        foreach (var a in ev.Sprites)
        {
            if (a.Sprite is not SpriteSpecifier.Rsi rsi)
                continue;

            var coords = GetCoordinates(a.coordinates);

            if (Deleted(coords.EntityId))
                continue;

            var ent = Spawn(HitscanProto, coords);
            var sprite = Comp<SpriteComponent>(ent);
            var xform = Transform(ent);
            xform.LocalRotation = a.angle;
            sprite[EffectLayers.Unshaded].AutoAnimated = false;
            sprite.LayerSetSprite(EffectLayers.Unshaded, rsi);
            sprite.LayerSetState(EffectLayers.Unshaded, rsi.RsiState);
            sprite.Scale = new Vector2(a.Distance, 1f);
            sprite[EffectLayers.Unshaded].Visible = true;

            var anim = new Animation()
            {
                Length = TimeSpan.FromSeconds(0.48f),
                AnimationTracks =
                {
                    new AnimationTrackSpriteFlick()
                    {
                        LayerKey = EffectLayers.Unshaded,
                        KeyFrames =
                        {
                            new AnimationTrackSpriteFlick.KeyFrame(rsi.RsiState, 0f),
                        }
                    }
                }
            };

            _animPlayer.Play(ent, anim, "hitscan-effect");
        }
    }

    public override void Update(float frameTime)
    {
        if (!Timing.IsFirstTimePredicted)
            return;

        var entityNull = _player.LocalEntity;

        if (entityNull == null || !TryComp<CombatModeComponent>(entityNull, out var combat) || !combat.IsInCombatMode)
        {
            return;
        }

        var entity = entityNull.Value;

        if (!TryGetGun(entity, out var gunUid, out var gun))
        {
            return;
        }

        var useKey = gun.UseKey ? EngineKeyFunctions.Use : EngineKeyFunctions.UseSecondary;

        if (_inputSystem.CmdStates.GetState(useKey) != BoundKeyState.Down)
        {
            if (gun.ShotCounter != 0)
                EntityManager.RaisePredictiveEvent(new RequestStopShootEvent { Gun = GetNetEntity(gunUid) });
            return;
        }

        if (gun.NextFire > Timing.CurTime)
            return;

        var mousePos = _eyeManager.PixelToMap(_inputManager.MouseScreenPosition);

        if (mousePos.MapId == MapId.Nullspace)
        {
            if (gun.ShotCounter != 0)
                EntityManager.RaisePredictiveEvent(new RequestStopShootEvent { Gun = GetNetEntity(gunUid) });

            return;
        }

        // Define target coordinates relative to gun entity, so that network latency on moving grids doesn't fuck up the target location.
        var coordinates = TransformSystem.ToCoordinates(entity, mousePos);

        NetEntity? target = null;
        if (_state.CurrentState is GameplayStateBase screen)
            target = GetNetEntity(screen.GetClickedEntity(mousePos));

        if (_player.LocalSession is not { } session)
            return;

        Log.Debug($"Sending shoot request tick {Timing.CurTick} / {Timing.CurTime}");

        var projectiles = ShootRequested(GetNetEntity(gunUid), GetNetCoordinates(coordinates), target, null, session);

        RaisePredictiveEvent(new RequestShootEvent()
        {
            Target = target,
            Coordinates = GetNetCoordinates(coordinates),
            Gun = GetNetEntity(gunUid),
            Shot = projectiles?.Select(e => e.Id).ToList(),
        });
    }

    protected override void Popup(string message, EntityUid? uid, EntityUid? user)
    {
        if (uid == null || user == null || !Timing.IsFirstTimePredicted)
            return;

        PopupSystem.PopupEntity(message, uid.Value, user.Value);
    }

    protected override void CreateEffect(EntityUid gunUid, MuzzleFlashEvent message, EntityUid? tracked = null, EntityUid? player = null)
    {
        if (!Timing.IsFirstTimePredicted)
            return;

        // EntityUid check added to stop throwing exceptions due to https://github.com/space-wizards/space-station-14/issues/28252
        // TODO: Check to see why invalid entities are firing effects.
        if (gunUid == EntityUid.Invalid)
        {
            Log.Debug($"Invalid Entity sent MuzzleFlashEvent (proto: {message.Prototype}, gun: {ToPrettyString(gunUid)})");
            return;
        }

        var gunXform = Transform(gunUid);
        var gridUid = gunXform.GridUid;
        EntityCoordinates coordinates;

        if (TryComp(gridUid, out MapGridComponent? mapGrid))
        {
            coordinates = new EntityCoordinates(gridUid.Value, _maps.LocalToGrid(gridUid.Value, mapGrid, gunXform.Coordinates));
        }
        else if (gunXform.MapUid != null)
        {
            coordinates = new EntityCoordinates(gunXform.MapUid.Value, TransformSystem.GetWorldPosition(gunXform));
        }
        else
        {
            return;
        }

        var ent = Spawn(message.Prototype, coordinates);
        TransformSystem.SetWorldRotationNoLerp(ent, message.Angle);

        if (tracked != null)
        {
            var track = EnsureComp<TrackUserComponent>(ent);
            track.User = tracked;
            track.Offset = Vector2.UnitX / 2f;
        }

        var lifetime = 0.4f;

        if (TryComp<TimedDespawnComponent>(gunUid, out var despawn))
        {
            lifetime = despawn.Lifetime;
        }

        var anim = new Animation()
        {
            Length = TimeSpan.FromSeconds(lifetime),
            AnimationTracks =
            {
                new AnimationTrackComponentProperty
                {
                    ComponentType = typeof(SpriteComponent),
                    Property = nameof(SpriteComponent.Color),
                    InterpolationMode = AnimationInterpolationMode.Linear,
                    KeyFrames =
                    {
                        new AnimationTrackProperty.KeyFrame(Color.White.WithAlpha(1f), 0),
                        new AnimationTrackProperty.KeyFrame(Color.White.WithAlpha(0f), lifetime)
                    }
                }
            }
        };

        _animPlayer.Play(ent, anim, "muzzle-flash");
        if (!TryComp(gunUid, out PointLightComponent? light))
        {
            light = (PointLightComponent)_factory.GetComponent(typeof(PointLightComponent));
            light.NetSyncEnabled = false;
            AddComp(gunUid, light);
        }

        Lights.SetEnabled(gunUid, true, light);
        Lights.SetRadius(gunUid, 2f, light);
        Lights.SetColor(gunUid, Color.FromHex("#cc8e2b"), light);
        Lights.SetEnergy(gunUid, 5f, light);

        var animTwo = new Animation()
        {
            Length = TimeSpan.FromSeconds(lifetime),
            AnimationTracks =
            {
                new AnimationTrackComponentProperty
                {
                    ComponentType = typeof(PointLightComponent),
                    Property = nameof(PointLightComponent.Energy),
                    InterpolationMode = AnimationInterpolationMode.Linear,
                    KeyFrames =
                    {
                        new AnimationTrackProperty.KeyFrame(5f, 0),
                        new AnimationTrackProperty.KeyFrame(0f, lifetime)
                    }
                },
                new AnimationTrackComponentProperty
                {
                    ComponentType = typeof(PointLightComponent),
                    Property = nameof(PointLightComponent.AnimatedEnable),
                    InterpolationMode = AnimationInterpolationMode.Linear,
                    KeyFrames =
                    {
                        new AnimationTrackProperty.KeyFrame(true, 0),
                        new AnimationTrackProperty.KeyFrame(false, lifetime)
                    }
                }
            }
        };

        var uidPlayer = EnsureComp<AnimationPlayerComponent>(gunUid);

        _animPlayer.Stop(gunUid, uidPlayer, "muzzle-flash-light");
        _animPlayer.Play((gunUid, uidPlayer), animTwo, "muzzle-flash-light");
    }

    public override void ShootProjectile(EntityUid uid,
        Vector2 direction,
        Vector2 gunVelocity,
        EntityUid gunUid,
        EntityUid? user = null,
        float speed = 20)
    {
        EnsureComp<PredictedProjectileClientComponent>(uid);
        _physics.UpdateIsPredicted(uid);
        base.ShootProjectile(uid, direction, gunVelocity, gunUid, user, speed);
    }
}