using System.Diagnostics.CodeAnalysis;
using Content.Shared.Armor;
using Content.Shared.Clothing.Components;
using Content.Shared.DoAfter;
using Content.Shared.Hands;
using Content.Shared.Hands.Components;
using Content.Shared.Hands.EntitySystems;
using Content.Shared.Interaction;
using Content.Shared.Inventory.Events;
using Content.Shared.Item;
using Content.Shared.Movement.Systems;
using Content.Shared.Popups;
using Content.Shared.Strip.Components;
using Content.Shared.Whitelist;
using Robust.Shared.Audio.Systems;
using Robust.Shared.Containers;
using Robust.Shared.Timing;
using Robust.Shared.Utility;

namespace Content.Shared.Inventory;

public abstract partial class InventorySystem
{
    [Dependency] private readonly SharedPopupSystem _popup = default!;
    [Dependency] private readonly MovementSpeedModifierSystem _movementSpeed = default!;
    [Dependency] private readonly SharedInteractionSystem _interactionSystem = default!;
    [Dependency] private readonly SharedItemSystem _item = default!;
    [Dependency] private readonly SharedAudioSystem _audio = default!;
    [Dependency] private readonly SharedContainerSystem _containerSystem = default!;
    [Dependency] private readonly SharedDoAfterSystem _doAfter = default!;
    [Dependency] private readonly SharedHandsSystem _handsSystem = default!;
    [Dependency] private readonly IGameTiming _gameTiming = default!;
    [Dependency] private readonly SharedTransformSystem _transform = default!;
    [Dependency] private readonly EntityWhitelistSystem _whitelistSystem = default!;

    [ValidatePrototypeId<ItemSizePrototype>]
    private const string PocketableItemSize = "Small";

    private void InitializeEquip()
    {
        //these events ensure that the client also gets its proper events raised when getting its containerstate updated
        SubscribeLocalEvent<InventoryComponent, EntInsertedIntoContainerMessage>(OnEntInserted);
        SubscribeLocalEvent<InventoryComponent, EntRemovedFromContainerMessage>(OnEntRemoved);

        SubscribeAllEvent<UseSlotNetworkMessage>(OnUseSlot);
    }

    private void OnEntRemoved(EntityUid uid, InventoryComponent component, EntRemovedFromContainerMessage args)
    {
        if(!TryGetSlot(uid, args.Container.ID, out var slotDef, inventory: component))
            return;

        var unequippedEvent = new DidUnequipEvent(uid, args.Entity, slotDef);
        RaiseLocalEvent(uid, unequippedEvent, true);

        var gotUnequippedEvent = new GotUnequippedEvent(uid, args.Entity, slotDef);
        RaiseLocalEvent(args.Entity, gotUnequippedEvent, true);
    }

    private void OnEntInserted(EntityUid uid, InventoryComponent component, EntInsertedIntoContainerMessage args)
    {
        if(!TryGetSlot(uid, args.Container.ID, out var slotDef, inventory: component))
           return;

        var equippedEvent = new DidEquipEvent(uid, args.Entity, slotDef);
        RaiseLocalEvent(uid, equippedEvent, true);

        var gotEquippedEvent = new GotEquippedEvent(uid, args.Entity, slotDef);
        RaiseLocalEvent(args.Entity, gotEquippedEvent, true);
    }

    /// <summary>
    ///     Will attempt to equip or unequip an item to/from the clicked slot. If the user clicked on an occupied slot
    ///     with some entity, will instead attempt to interact with this entity.
    /// </summary>
    private void OnUseSlot(UseSlotNetworkMessage ev, EntitySessionEventArgs eventArgs)
    {
        if (eventArgs.SenderSession.AttachedEntity is not { Valid: true } actor)
            return;

        if (!TryComp(actor, out InventoryComponent? inventory) || !TryComp<HandsComponent>(actor, out var hands))
            return;

        var held = hands.ActiveHandEntity;
        TryGetSlotEntity(actor, ev.Slot, out var itemUid, inventory);

        // attempt to perform some interaction
        if (held != null && itemUid != null)
        {
            _interactionSystem.InteractUsing(actor, held.Value, itemUid.Value,
                Transform(itemUid.Value).Coordinates);
            return;
        }

        // unequip the item.
        if (itemUid != null)
        {
            if (!TryUnequip(actor, ev.Slot, out var item, predicted: true, inventory: inventory, checkDoafter: true))
                return;

            _handsSystem.PickupOrDrop(actor, item.Value);
            return;
        }

        // finally, just try to equip the held item.
        if (held == null)
            return;

        // before we drop the item, check that it can be equipped in the first place.
        if (!CanEquip(actor, held.Value, ev.Slot, out var reason))
        {
            _popup.PopupCursor(Loc.GetString(reason));
            return;
        }

        if (!_handsSystem.CanDropHeld(actor, hands.ActiveHand!, checkActionBlocker: false))
            return;

        RaiseLocalEvent(held.Value, new HandDeselectedEvent(actor));

        TryEquip(actor, actor, held.Value, ev.Slot, predicted: true, inventory: inventory, force: true, checkDoafter:true);
    }

    public bool TryEquip(EntityUid uid, EntityUid itemUid, string slot, bool silent = false, bool force = false, bool predicted = false,
        InventoryComponent? inventory = null, ClothingComponent? clothing = null, bool checkDoafter = false) =>
        TryEquip(uid, uid, itemUid, slot, silent, force, predicted, inventory, clothing, checkDoafter);

    public bool TryEquip(EntityUid actor, EntityUid target, EntityUid itemUid, string slot, bool silent = false, bool force = false, bool predicted = false,
        InventoryComponent? inventory = null, ClothingComponent? clothing = null, bool checkDoafter = false)
    {
        if (!Resolve(target, ref inventory, false))
        {
            if(!silent)
                _popup.PopupCursor(Loc.GetString("inventory-component-can-equip-cannot"));
            return false;
        }

        // Not required to have, since pockets can take any item.
        // CanEquip will still check, so we don't have to worry about it.
        Resolve(itemUid, ref clothing, false);

        if (!TryGetSlotContainer(target, slot, out var slotContainer, out var slotDefinition, inventory))
        {
            if(!silent)
                _popup.PopupCursor(Loc.GetString("inventory-component-can-equip-cannot"));
            return false;
        }

        if (!force && !CanEquip(actor, target, itemUid, slot, out var reason, slotDefinition, inventory, clothing))
        {
            if(!silent)
                _popup.PopupCursor(Loc.GetString(reason));
            return false;
        }

        if (checkDoafter &&
            clothing != null &&
            clothing.EquipDelay > TimeSpan.Zero &&
            (clothing.Slots & slotDefinition.SlotFlags) != 0 &&
            _containerSystem.CanInsert(itemUid, slotContainer))
        {
            var args = new DoAfterArgs(
                EntityManager,
                actor,
                clothing.EquipDelay,
                new ClothingEquipDoAfterEvent(slot),
                itemUid,
                target,
                itemUid)
            {
                BreakOnMove = true,
                NeedHand = true,
            };

            _doAfter.TryStartDoAfter(args);
            return false;
        }

        if (!_containerSystem.Insert(itemUid, slotContainer))
        {
            if(!silent)
                _popup.PopupCursor(Loc.GetString("inventory-component-can-unequip-cannot"));
            return false;
        }

        if (!silent && clothing != null)
        {
            _audio.PlayPredicted(clothing.EquipSound, target, actor);
        }

        Dirty(target, inventory);

        _movementSpeed.RefreshMovementSpeedModifiers(target);

        return true;
    }

    public bool CanAccess(EntityUid actor, EntityUid target, EntityUid itemUid)
    {
        // if the item is something like a hardsuit helmet, it may be contained within the hardsuit.
        // in that case, we check accesibility for the owner-entity instead.
        if (TryComp(itemUid, out AttachedClothingComponent? attachedComp))
            itemUid = attachedComp.AttachedUid;

        // Can the actor reach the target?
        if (actor != target && !(_interactionSystem.InRangeUnobstructed(actor, target) && _containerSystem.IsInSameOrParentContainer(actor, target)))
            return false;

        // Can the actor reach the item?
        if (_interactionSystem.InRangeAndAccessible(actor, itemUid))
            return true;

        // Is the actor currently stripping the target? Here we could check if the actor has the stripping UI open, but
        // that requires server/client specific code.
        // Uhhh TODO, fix this. This doesn't even fucking check if the target item is IN the targets inventory.
        return actor != target &&
            HasComp<StrippableComponent>(target) &&
            HasComp<StrippingComponent>(actor) &&
            HasComp<HandsComponent>(actor);
    }

    public bool CanEquip(EntityUid uid, EntityUid itemUid, string slot, [NotNullWhen(false)] out string? reason,
        SlotDefinition? slotDefinition = null, InventoryComponent? inventory = null,
        ClothingComponent? clothing = null, ItemComponent? item = null) =>
        CanEquip(uid, uid, itemUid, slot, out reason, slotDefinition, inventory, clothing, item);

    public bool CanEquip(EntityUid actor, EntityUid target, EntityUid itemUid, string slot, [NotNullWhen(false)] out string? reason, SlotDefinition? slotDefinition = null,
        InventoryComponent? inventory = null, ClothingComponent? clothing = null, ItemComponent? item = null)
    {
        reason = "inventory-component-can-equip-cannot";
        if (!Resolve(target, ref inventory, false))
            return false;

        Resolve(itemUid, ref clothing, ref item, false);

        if (slotDefinition == null && !TryGetSlot(target, slot, out slotDefinition, inventory: inventory))
            return false;

        DebugTools.Assert(slotDefinition.Name == slot);
        if (slotDefinition.DependsOn != null)
        {
            if (!TryGetSlotEntity(target, slotDefinition.DependsOn, out EntityUid? slotEntity, inventory))
                return false;

            if (slotDefinition.DependsOnComponents is { } componentRegistry)
            {
                foreach (var (_, entry) in componentRegistry)
                {
                    if (!HasComp(slotEntity, entry.Component.GetType()))
                        return false;

                    if (TryComp<AllowSuitStorageComponent>(slotEntity, out var comp) &&
                        _whitelistSystem.IsWhitelistFailOrNull(comp.Whitelist, itemUid))
                        return false;
                }
            }
        }

        var fittingInPocket = slotDefinition.SlotFlags.HasFlag(SlotFlags.POCKET) &&
                              item != null &&
                              _item.GetSizePrototype(item.Size) <= _item.GetSizePrototype(PocketableItemSize);
        if (clothing == null && !fittingInPocket
            || clothing != null && !clothing.Slots.HasFlag(slotDefinition.SlotFlags) && !fittingInPocket)
        {
            reason = "inventory-component-can-equip-does-not-fit";
            return false;
        }

        if (!CanAccess(actor, target, itemUid))
        {
            reason = "interaction-system-user-interaction-cannot-reach";
            return false;
        }

        if (_whitelistSystem.IsWhitelistFail(slotDefinition.Whitelist, itemUid) ||
            _whitelistSystem.IsBlacklistPass(slotDefinition.Blacklist, itemUid))
        {
            reason = "inventory-component-can-equip-does-not-fit";
            return false;
        }

        var attemptEvent = new IsEquippingAttemptEvent(actor, target, itemUid, slotDefinition);
        RaiseLocalEvent(target, attemptEvent, true);
        if (attemptEvent.Cancelled)
        {
            reason = attemptEvent.Reason ?? reason;
            return false;
        }

        if (actor != target)
        {
            //reuse the event. this is gucci, right?
            attemptEvent.Reason = null;
            RaiseLocalEvent(actor, attemptEvent, true);
            if (attemptEvent.Cancelled)
            {
                reason = attemptEvent.Reason ?? reason;
                return false;
            }
        }

        var itemAttemptEvent = new BeingEquippedAttemptEvent(actor, target, itemUid, slotDefinition);
        RaiseLocalEvent(itemUid, itemAttemptEvent, true);
        if (itemAttemptEvent.Cancelled)
        {
            reason = itemAttemptEvent.Reason ?? reason;
            return false;
        }
        return true;
    }

    public bool TryUnequip(
        EntityUid uid,
        string slot,
        bool silent = false,
        bool force = false,
        bool predicted = false,
        InventoryComponent? inventory = null,
        ClothingComponent? clothing = null,
        bool reparent = true,
        bool checkDoafter = false)
    {
        return TryUnequip(uid, uid, slot, silent, force, predicted, inventory, clothing, reparent, checkDoafter);
    }

    public bool TryUnequip(
        EntityUid actor,
        EntityUid target,
        string slot,
        bool silent = false,
        bool force = false,
        bool predicted = false,
        InventoryComponent? inventory = null,
        ClothingComponent? clothing = null,
        bool reparent = true,
        bool checkDoafter = false)
    {
        return TryUnequip(actor, target, slot, out _, silent, force, predicted, inventory, clothing, reparent, checkDoafter);
    }

    public bool TryUnequip(
        EntityUid uid,
        string slot,
        [NotNullWhen(true)] out EntityUid? removedItem,
        bool silent = false,
        bool force = false,
        bool predicted = false,
        InventoryComponent? inventory = null,
        ClothingComponent? clothing = null,
        bool reparent = true,
        bool checkDoafter = false)
    {
        return TryUnequip(uid, uid, slot, out removedItem, silent, force, predicted, inventory, clothing, reparent, checkDoafter);
    }

    public bool TryUnequip(
        EntityUid actor,
        EntityUid target,
        string slot,
        [NotNullWhen(true)] out EntityUid? removedItem,
        bool silent = false,
        bool force = false,
        bool predicted = false,
        InventoryComponent? inventory = null,
        ClothingComponent? clothing = null,
        bool reparent = true,
        bool checkDoafter = false)
    {
        removedItem = null;

        if (TerminatingOrDeleted(target))
            return false;

        if (!Resolve(target, ref inventory, false))
        {
            if(!silent)
                _popup.PopupCursor(Loc.GetString("inventory-component-can-unequip-cannot"));
            return false;
        }

        if (!TryGetSlotContainer(target, slot, out var slotContainer, out var slotDefinition, inventory))
        {
            if(!silent)
                _popup.PopupCursor(Loc.GetString("inventory-component-can-unequip-cannot"));
            return false;
        }

        removedItem = slotContainer.ContainedEntity;

        if (!removedItem.HasValue || TerminatingOrDeleted(removedItem.Value))
            return false;

        if (!force && !CanUnequip(actor, target, slot, out var reason, slotContainer, slotDefinition, inventory))
        {
            if(!silent)
                _popup.PopupCursor(Loc.GetString(reason));
            return false;
        }

        //we need to do this to make sure we are 100% removing this entity, since we are now dropping dependant slots
        if (!force && !_containerSystem.CanRemove(removedItem.Value, slotContainer))
            return false;

        if (checkDoafter &&
            Resolve(removedItem.Value, ref clothing, false) &&
            (clothing.Slots & slotDefinition.SlotFlags) != 0 &&
            clothing.UnequipDelay > TimeSpan.Zero)
        {
            var args = new DoAfterArgs(
                EntityManager,
                actor,
                clothing.UnequipDelay,
                new ClothingUnequipDoAfterEvent(slot),
                removedItem.Value,
                target,
                removedItem.Value)
            {
                BreakOnMove = true,
                NeedHand = true,
            };

            _doAfter.TryStartDoAfter(args);
            return false;
        }

        foreach (var slotDef in inventory.Slots)
        {
            if (slotDef != slotDefinition && slotDef.DependsOn == slotDefinition.Name)
            {
                //this recursive call might be risky
                TryUnequip(actor, target, slotDef.Name, true, true, predicted, inventory, reparent: reparent);
            }
        }

        if (!_containerSystem.Remove(removedItem.Value, slotContainer, force: force, reparent: reparent))
            return false;

        // TODO: Inventory needs a hot cleanup hoo boy
        // Check if something else (AKA toggleable) dumped it into a container.
        if (!_containerSystem.IsEntityInContainer(removedItem.Value))
            _transform.DropNextTo(removedItem.Value, target);

        if (!silent && Resolve(removedItem.Value, ref clothing, false) && clothing.UnequipSound != null)
        {
            _audio.PlayPredicted(clothing.UnequipSound, target, actor);
        }

        Dirty(target, inventory);

        _movementSpeed.RefreshMovementSpeedModifiers(target);

        return true;
    }

    public bool CanUnequip(EntityUid uid, string slot, [NotNullWhen(false)] out string? reason,
        ContainerSlot? containerSlot = null, SlotDefinition? slotDefinition = null,
        InventoryComponent? inventory = null) =>
        CanUnequip(uid, uid, slot, out reason, containerSlot, slotDefinition, inventory);

    public bool CanUnequip(EntityUid actor, EntityUid target, string slot, [NotNullWhen(false)] out string? reason, ContainerSlot? containerSlot = null, SlotDefinition? slotDefinition = null, InventoryComponent? inventory = null)
    {
        reason = "inventory-component-can-unequip-cannot";
        if (!Resolve(target, ref inventory, false))
            return false;

        if ((containerSlot == null || slotDefinition == null) && !TryGetSlotContainer(target, slot, out containerSlot, out slotDefinition, inventory))
            return false;

        if (containerSlot.ContainedEntity is not {} itemUid)
            return false;

        if (!_containerSystem.CanRemove(itemUid, containerSlot))
            return false;

        // make sure the user can actually reach the target
        if (!CanAccess(actor, target, itemUid))
        {
            reason = "interaction-system-user-interaction-cannot-reach";
            return false;
        }

        var attemptEvent = new IsUnequippingAttemptEvent(actor, target, itemUid, slotDefinition);
        RaiseLocalEvent(target, attemptEvent, true);
        if (attemptEvent.Cancelled)
        {
            reason = attemptEvent.Reason ?? reason;
            return false;
        }

        if (actor != target)
        {
            //reuse the event. this is gucci, right?
            attemptEvent.Reason = null;
            RaiseLocalEvent(actor, attemptEvent, true);
            if (attemptEvent.Cancelled)
            {
                reason = attemptEvent.Reason ?? reason;
                return false;
            }
        }

        var itemAttemptEvent = new BeingUnequippedAttemptEvent(actor, target, itemUid, slotDefinition);
        RaiseLocalEvent(itemUid, itemAttemptEvent, true);
        if (itemAttemptEvent.Cancelled)
        {
            reason = attemptEvent.Reason ?? reason;
            return false;
        }

        return true;
    }

    public bool TryGetSlotEntity(EntityUid uid, string slot, [NotNullWhen(true)] out EntityUid? entityUid, InventoryComponent? inventoryComponent = null, ContainerManagerComponent? containerManagerComponent = null)
    {
        entityUid = null;
        if (!Resolve(uid, ref inventoryComponent, ref containerManagerComponent, false)
            || !TryGetSlotContainer(uid, slot, out var container, out _, inventoryComponent, containerManagerComponent))
            return false;

        entityUid = container.ContainedEntity;
        return entityUid != null;
    }
}