tbd-station-14/Content.Server/GameObjects/Components/Damage/DamageOnHighSpeedImpactComponent.cs

using System;
using Content.Server.GameObjects.Components.Mobs;
using Content.Shared.Audio;
using Content.Shared.Damage;
using Content.Shared.GameObjects.Components.Damage;
using Robust.Server.GameObjects;
using Robust.Shared.GameObjects;
using Robust.Shared.IoC;
using Robust.Shared.Physics;
using Robust.Shared.Random;
using Robust.Shared.Serialization;
using Robust.Shared.Timing;

namespace Content.Server.GameObjects.Components.Damage
{
    [RegisterComponent]
    public class DamageOnHighSpeedImpactComponent : Component, ICollideBehavior
    {
        [Dependency] private readonly IRobustRandom _robustRandom = default!;
        [Dependency] private readonly IGameTiming _gameTiming = default!;

        public override string Name => "DamageOnHighSpeedImpact";

        public DamageType Damage { get; set; } = DamageType.Blunt;
        public float MinimumSpeed { get; set; } = 20f;
        public int BaseDamage { get; set; } = 5;
        public float Factor { get; set; } = 0.75f;
        public string SoundHit { get; set; } = "";
        public float StunChance { get; set; } = 0.25f;
        public int StunMinimumDamage { get; set; } = 10;
        public float StunSeconds { get; set; } = 1f;
        public float DamageCooldown { get; set; } = 2f;
        private TimeSpan _lastHit = TimeSpan.Zero;

        public override void ExposeData(ObjectSerializer serializer)
        {
            base.ExposeData(serializer);

            serializer.DataField(this, x => x.Damage, "damage", DamageType.Blunt);
            serializer.DataField(this, x => x.MinimumSpeed, "minimumSpeed", 20f);
            serializer.DataField(this, x => x.BaseDamage, "baseDamage", 5);
            serializer.DataField(this, x => x.Factor, "factor", 1f);
            serializer.DataField(this, x => x.SoundHit, "soundHit", "");
            serializer.DataField(this, x => x.StunChance, "stunChance", 0.25f);
            serializer.DataField(this, x => x.StunSeconds, "stunSeconds", 1f);
            serializer.DataField(this, x => x.DamageCooldown, "damageCooldown", 2f);
            serializer.DataField(this, x => x.StunMinimumDamage, "stunMinimumDamage", 10);
        }

        public void CollideWith(IPhysBody ourBody, IPhysBody otherBody)
        {
            if (!Owner.TryGetComponent(out IDamageableComponent damageable)) return;

            var speed = ourBody.LinearVelocity.Length;

            if (speed < MinimumSpeed) return;

            if(!string.IsNullOrEmpty(SoundHit))
                EntitySystem.Get<AudioSystem>().PlayFromEntity(SoundHit, otherBody.Entity, AudioHelpers.WithVariation(0.125f).WithVolume(-0.125f));

            if ((_gameTiming.CurTime - _lastHit).TotalSeconds < DamageCooldown)
                return;

            _lastHit = _gameTiming.CurTime;

            var damage = (int) (BaseDamage * (speed / MinimumSpeed) * Factor);

            if (Owner.TryGetComponent(out StunnableComponent stun) && _robustRandom.Prob(StunChance))
                stun.Stun(StunSeconds);

            damageable.ChangeDamage(Damage, damage, false, otherBody.Entity);
        }
    }
}