#nullable enable
using System;
using Content.Server.Atmos;
using Content.Server.Explosions;
using Content.Server.GameObjects.Components.Body.Respiratory;
using Content.Server.Interfaces;
using Content.Server.Utility;
using Content.Shared.Actions;
using Content.Shared.Atmos;
using Content.Shared.Audio;
using Content.Shared.GameObjects.Components.Atmos.GasTank;
using Content.Shared.GameObjects.Components.Mobs;
using Content.Shared.GameObjects.EntitySystems;
using Content.Shared.GameObjects.Verbs;
using Content.Shared.Interfaces.GameObjects.Components;
using JetBrains.Annotations;
using Robust.Server.GameObjects.Components.UserInterface;
using Robust.Server.GameObjects.EntitySystems;
using Robust.Server.Interfaces.GameObjects;
using Robust.Server.Interfaces.Player;
using Robust.Shared.Containers;
using Robust.Shared.GameObjects;
using Robust.Shared.GameObjects.ComponentDependencies;
using Robust.Shared.GameObjects.Systems;
using Robust.Shared.Interfaces.GameObjects;
using Robust.Shared.Localization;
using Robust.Shared.Serialization;
using Robust.Shared.Utility;
using Robust.Shared.ViewVariables;

namespace Content.Server.GameObjects.Components.Atmos
{
    [RegisterComponent]
    [ComponentReference(typeof(IActivate))]
    public class GasTankComponent : SharedGasTankComponent, IExamine, IGasMixtureHolder, IUse, IDropped, IActivate
    {
        private const float MaxExplosionRange = 14f;
        private const float DefaultOutputPressure = Atmospherics.OneAtmosphere;

        private float _pressureResistance;

        private int _integrity = 3;

        [ComponentDependency] private readonly ItemActionsComponent? _itemActions = null;

        [ViewVariables] private BoundUserInterface? _userInterface;

        [ViewVariables] public GasMixture? Air { get; set; }

        /// <summary>
        ///     Distributed pressure.
        /// </summary>
        [ViewVariables] public float OutputPressure { get; private set; }

        /// <summary>
        ///     Tank is connected to internals.
        /// </summary>
        [ViewVariables] public bool IsConnected { get; set; }

        /// <summary>
        ///     Represents that tank is functional and can be connected to internals.
        /// </summary>
        public bool IsFunctional => GetInternalsComponent() != null;

        /// <summary>
        ///     Pressure at which tanks start leaking.
        /// </summary>
        public float TankLeakPressure { get; set; }     = 30 * Atmospherics.OneAtmosphere;

        /// <summary>
        ///     Pressure at which tank spills all contents into atmosphere.
        /// </summary>
        public float TankRupturePressure { get; set; }  = 40 * Atmospherics.OneAtmosphere;

        /// <summary>
        ///     Base 3x3 explosion.
        /// </summary>
        public float TankFragmentPressure { get; set; } = 50 * Atmospherics.OneAtmosphere;

        /// <summary>
        ///     Increases explosion for each scale kPa above threshold.
        /// </summary>
        public float TankFragmentScale { get; set; }    = 10 * Atmospherics.OneAtmosphere;

        public override void Initialize()
        {
            base.Initialize();
            _userInterface = Owner.GetUIOrNull(SharedGasTankUiKey.Key);
            if (_userInterface != null)
            {
                _userInterface.OnReceiveMessage += UserInterfaceOnOnReceiveMessage;
            }
        }

        public void OpenInterface(IPlayerSession session)
        {
            _userInterface?.Open(session);
            UpdateUserInterface(true);
        }

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

            serializer.DataField(this, x => x.Air, "air", new GasMixture());
            serializer.DataField(this, x => x.OutputPressure, "outputPressure", DefaultOutputPressure);
            serializer.DataField(this, x => x.TankLeakPressure, "tankLeakPressure", 30 * Atmospherics.OneAtmosphere);
            serializer.DataField(this, x => x.TankRupturePressure, "tankRupturePressure", 40 * Atmospherics.OneAtmosphere);
            serializer.DataField(this, x => x.TankFragmentPressure, "tankFragmentPressure", 50 * Atmospherics.OneAtmosphere);
            serializer.DataField(this, x => x.TankFragmentScale, "tankFragmentScale", 10 * Atmospherics.OneAtmosphere);
            serializer.DataField(ref _pressureResistance, "pressureResistance", Atmospherics.OneAtmosphere * 5f);
        }

        public void Examine(FormattedMessage message, bool inDetailsRange)
        {
            message.AddMarkup(Loc.GetString("Pressure: [color=orange]{0}[/color] kPa.\n",
                Math.Round(Air?.Pressure ?? 0)));
            if (IsConnected)
            {
                message.AddMarkup(Loc.GetString("Connected to external component"));
            }
        }

        protected override void Shutdown()
        {
            base.Shutdown();
            DisconnectFromInternals();
        }

        public void Update()
        {
            Air?.React(this);
            CheckStatus();
            UpdateUserInterface();
        }

        public GasMixture? RemoveAir(float amount)
        {
            var gas = Air?.Remove(amount);
            CheckStatus();
            return gas;
        }

        public GasMixture RemoveAirVolume(float volume)
        {
            if (Air == null)
                return new GasMixture(volume);

            var tankPressure = Air.Pressure;
            if (tankPressure < OutputPressure)
            {
                OutputPressure = tankPressure;
                UpdateUserInterface();
            }

            var molesNeeded = OutputPressure * volume / (Atmospherics.R * Air.Temperature);

            var air = RemoveAir(molesNeeded);

            if (air != null)
                air.Volume = volume;
            else
                return new GasMixture(volume);

            return air;
        }

        public bool UseEntity(UseEntityEventArgs eventArgs)
        {
            if (!eventArgs.User.TryGetComponent(out IActorComponent? actor)) return false;
            OpenInterface(actor.playerSession);
            return true;
        }

        public void Activate(ActivateEventArgs eventArgs)
        {
            if (!eventArgs.User.TryGetComponent(out IActorComponent? actor)) return;
            OpenInterface(actor.playerSession);
        }

        public void ConnectToInternals()
        {
            if (IsConnected || !IsFunctional) return;
            var internals = GetInternalsComponent();
            if (internals == null) return;
            IsConnected = internals.TryConnectTank(Owner);
            UpdateUserInterface();
        }

        public void DisconnectFromInternals(IEntity? owner = null)
        {
            if (!IsConnected) return;
            IsConnected = false;
            GetInternalsComponent(owner)?.DisconnectTank();
            UpdateUserInterface();
        }

        private void UpdateUserInterface(bool initialUpdate = false)
        {
            var internals = GetInternalsComponent();
            _userInterface?.SetState(
                new GasTankBoundUserInterfaceState
                {
                    TankPressure = Air?.Pressure ?? 0,
                    OutputPressure = initialUpdate ? OutputPressure : (float?) null,
                    InternalsConnected = IsConnected,
                    CanConnectInternals = IsFunctional && internals != null
                });

            if (internals == null) return;
            _itemActions?.GrantOrUpdate(ItemActionType.ToggleInternals, IsFunctional, IsConnected);
        }

        private void UserInterfaceOnOnReceiveMessage(ServerBoundUserInterfaceMessage message)
        {
            switch (message.Message)
            {
                case GasTankSetPressureMessage msg:
                    OutputPressure = msg.Pressure;
                    break;
                case GasTankToggleInternalsMessage _:
                    ToggleInternals();
                    break;
            }
        }

        internal void ToggleInternals()
        {
            if (!ActionBlockerSystem.CanUse(GetInternalsComponent()?.Owner)) return;
            if (IsConnected)
            {
                DisconnectFromInternals();
                return;
            }

            ConnectToInternals();
        }

        private InternalsComponent? GetInternalsComponent(IEntity? owner = null)
        {
            if (Owner.Deleted) return null;
            if (owner != null) return owner.GetComponentOrNull<InternalsComponent>();
            return Owner.TryGetContainer(out var container)
                ? container.Owner.GetComponentOrNull<InternalsComponent>()
                : null;
        }

        public void AssumeAir(GasMixture giver)
        {
            Air?.Merge(giver);
            CheckStatus();
        }

        private void CheckStatus()
        {
            if (Air == null)
                return;

            var pressure = Air.Pressure;

            if (pressure > TankFragmentPressure)
            {
                // Give the gas a chance to build up more pressure.
                for (var i = 0; i < 3; i++)
                {
                    Air.React(this);
                }

                pressure = Air.Pressure;
                var range = (pressure - TankFragmentPressure) / TankFragmentScale;

                // Let's cap the explosion, yeah?
                if (range > MaxExplosionRange)
                {
                    range = MaxExplosionRange;
                }

                Owner.SpawnExplosion((int) (range * 0.25f), (int) (range * 0.5f), (int) (range * 1.5f), 1);

                Owner.Delete();
                return;
            }

            if (pressure > TankRupturePressure)
            {
                if (_integrity <= 0)
                {
                    var tileAtmos = Owner.Transform.Coordinates.GetTileAtmosphere();
                    tileAtmos?.AssumeAir(Air);

                    EntitySystem.Get<AudioSystem>().PlayAtCoords("Audio/Effects/spray.ogg", Owner.Transform.Coordinates,
                        AudioHelpers.WithVariation(0.125f));

                    Owner.Delete();
                    return;
                }

                _integrity--;
                return;
            }

            if (pressure > TankLeakPressure)
            {
                if (_integrity <= 0)
                {
                    var tileAtmos = Owner.Transform.Coordinates.GetTileAtmosphere();
                    if (tileAtmos == null)
                        return;

                    var leakedGas = Air.RemoveRatio(0.25f);
                    tileAtmos.AssumeAir(leakedGas);
                }
                else
                {
                    _integrity--;
                }

                return;
            }

            if (_integrity < 3)
                _integrity++;
        }

        public void Dropped(DroppedEventArgs eventArgs)
        {
            DisconnectFromInternals(eventArgs.User);
        }

        /// <summary>
        /// Open interaction window
        /// </summary>
        [Verb]
        private sealed class ControlVerb : Verb<GasTankComponent>
        {
            public override bool RequireInteractionRange => true;

            protected override void GetData(IEntity user, GasTankComponent component, VerbData data)
            {
                data.Visibility = VerbVisibility.Invisible;
                if (!user.HasComponent<IActorComponent>())
                {
                    return;
                }

                data.Visibility = VerbVisibility.Visible;
                data.Text = "Open Control Panel";
            }

            protected override void Activate(IEntity user, GasTankComponent component)
            {
                if (!user.TryGetComponent<IActorComponent>(out var actor))
                {
                    return;
                }

                component.OpenInterface(actor.playerSession);
            }
        }
    }

    [UsedImplicitly]
    public class ToggleInternalsAction : IToggleItemAction
    {
        public void ExposeData(ObjectSerializer serializer) {}

        public bool DoToggleAction(ToggleItemActionEventArgs args)
        {
            if (!args.Item.TryGetComponent<GasTankComponent>(out var gasTankComponent)) return false;
            // no change
            if (gasTankComponent.IsConnected == args.ToggledOn) return false;
            gasTankComponent.ToggleInternals();
            // did we successfully toggle to the desired status?
            return gasTankComponent.IsConnected == args.ToggledOn;
        }
    }
}