using Comfort.Common;
using Diz.LanguageExtensions;
using EFT;
using EFT.InventoryLogic;
using EFT.UI;
using EFT.UI.DragAndDrop;
using HarmonyLib;
using SPT.Reflection.Patching;
using SPT.Reflection.Utils;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Reflection;
using UnityEngine;
using UnityEngine.EventSystems;

namespace UIFixes
{
    public static class SwapPatches
    {
        // Source container for the drag - grab this early to check it
        private static IContainer SourceContainer;

        // Whether it's being called from the "check every slot" loop
        private static bool InHighlight = false;

        // The most recent CheckItemFilter result - needed to differentiate "No room" from incompatible
        private static string LastCheckItemFilterId;
        private static bool LastCheckItemFilterResult;

        // The most recent GridItemView that was hovered - needed to forcibly update hover state after swap
        private static GridItemView LastHoveredGridItemView;

        private static readonly EOwnerType[] BannedOwnerTypes = [EOwnerType.Mail, EOwnerType.Trader];

        public static bool BlockSwaps = false;

        public static void Enable()
        {
            new DetectSwapSourceContainerPatch().Enable();
            new CleanupSwapSourceContainerPatch().Enable();
            new GridViewCanAcceptSwapPatch().Enable();
            new DetectGridHighlightPrecheckPatch().Enable();
            new DetectSlotHighlightPrecheckPatch().Enable();
            new SlotCanAcceptSwapPatch().Enable();
            new DetectFilterForSwapPatch().Enable();
            new FixNoGridErrorPatch().Enable();
            new SwapOperationRaiseEventsPatch().Enable();
            new RememberSwapGridHoverPatch().Enable();
            new InspectWindowUpdateStatsOnSwapPatch().Enable();
            new FixAddModFirearmOperationPatch().Enable();
            new HideScaryTooltipPatch().Enable();
        }

        private static bool ValidPrerequisites(DragItemContext itemContext, ItemContextAbstractClass targetItemContext, IInventoryEventResult operation)
        {
            if (!Settings.SwapItems.Value)
            {
                return false;
            }

            // Haha no
            if (MultiSelect.Active)
            {
                return false;
            }

            if (BlockSwaps)
            {
                return false;
            }

            if (InHighlight || itemContext == null || targetItemContext == null || operation.Succeeded)
            {
                return false;
            }

            if (BannedOwnerTypes.Contains(itemContext.Item.Owner.OwnerType) || BannedOwnerTypes.Contains(targetItemContext.Item.Owner.OwnerType))
            {
                return false;
            }

            if (itemContext.Item == targetItemContext.Item || targetItemContext.Item.GetAllParentItems().Contains(itemContext.Item))
            {
                return false;
            }

            // Check if the source container is a non-interactable GridView. Specifically for StashSearch, but may exist in other scenarios?
            if (SourceContainer != null && SourceContainer is GridView && new R.GridView(SourceContainer).NonInteractable)
            {
                return false;
            }

            string error = operation.Error.ToString();

            // Since 3.9 containers and items with slots return the same "no free room" error. If the item doesn't have grids it's not a container.
            bool isContainer = targetItemContext.Item is LootItemClass compoundItem && compoundItem.Grids.Length > 0;
            if (Settings.SwapImpossibleContainers.Value && isContainer && !Plugin.InRaid() && error.StartsWith("No free room"))
            {
                // Check if it isn't allowed in that container, if so try to swap
                if (LastCheckItemFilterId == itemContext.Item.Id && !LastCheckItemFilterResult)
                {
                    return true;
                }

                // Check if it would ever fit no matter what, if not try to swap
                if (!CouldEverFit(itemContext, targetItemContext))
                {
                    return true;
                }
            }

            if (!error.EndsWith("not applicable") && !(error.StartsWith("Cannot apply") && !error.EndsWith("modified")) && error != "InventoryError/NoPossibleActions")
            {
                return false;
            }

            return true;
        }

        private static bool CouldEverFit(DragItemContext itemContext, ItemContextAbstractClass containerItemContext)
        {
            Item item = itemContext.Item;
            if (containerItemContext.Item is not LootItemClass container)
            {
                return false;
            }

            var size = item.CalculateCellSize();
            var rotatedSize = item.CalculateRotatedSize(itemContext.ItemRotation == ItemRotation.Horizontal ? ItemRotation.Vertical : ItemRotation.Horizontal);

            foreach (StashGridClass grid in container.Grids)
            {
                if (size.X <= grid.GridWidth.Value && size.Y <= grid.GridHeight.Value ||
                    rotatedSize.X <= grid.GridWidth.Value && rotatedSize.Y <= grid.GridHeight.Value)
                {
                    return true;
                }
            }

            return false;
        }

        public class DetectSwapSourceContainerPatch : ModulePatch
        {
            protected override MethodBase GetTargetMethod()
            {
                return AccessTools.Method(typeof(ItemView), nameof(ItemView.OnDrag));
            }

            [PatchPrefix]
            public static void Prefix(ItemView __instance)
            {
                SourceContainer = __instance.Container;
            }
        }

        public class CleanupSwapSourceContainerPatch : ModulePatch
        {
            protected override MethodBase GetTargetMethod()
            {
                return AccessTools.Method(typeof(ItemView), nameof(ItemView.OnEndDrag));
            }

            [PatchPrefix]
            public static void Prefix()
            {
                SourceContainer = null;
            }
        }

        public class GridViewCanAcceptSwapPatch : ModulePatch
        {
            protected override MethodBase GetTargetMethod()
            {
                return AccessTools.Method(typeof(GridView), nameof(GridView.CanAccept));
            }

            // Essentially doing what happens in StashGridClass.method_6, which checks if any of the squares are already taken
            // This looks at the squares taken by the two items and sees if any are the same
            private static bool ItemsOverlap(Item itemA, ItemAddress itemAddressA, Item itemB, ItemAddress itemAddressB)
            {
                if (itemAddressA.Container != itemAddressB.Container)
                {
                    return false;
                }

                if (itemAddressA is GridItemAddress gridItemAddressA && itemAddressB is GridItemAddress gridItemAddressB)
                {
                    LocationInGrid locationA = gridItemAddressA.LocationInGrid;
                    LocationInGrid locationB = gridItemAddressB.LocationInGrid;
                    StashGridClass grid = gridItemAddressA.Grid;

                    var itemASize = itemA.CalculateRotatedSize(locationA.r);
                    var itemASlots = new List<int>();
                    for (int y = 0; y < itemASize.Y; y++)
                    {
                        for (int x = 0; x < itemASize.X; x++)
                        {
                            itemASlots.Add((locationA.y + y) * grid.GridWidth.Value + locationA.x + x);
                        }
                    }

                    var itemBSize = itemB.CalculateRotatedSize(locationB.r);
                    for (int y = 0; y < itemBSize.Y; y++)
                    {
                        for (int x = 0; x < itemBSize.X; x++)
                        {
                            int num = (locationB.y + y) * grid.GridWidth.Value + locationB.x + x;
                            if (itemASlots.Contains(num))
                            {
                                return true;
                            }
                        }
                    }
                }

                return false;
            }

            [PatchPostfix]
            public static void Postfix(GridView __instance, DragItemContext itemContext, ItemContextAbstractClass targetItemContext, ref IInventoryEventResult operation, ref bool __result, Dictionary<string, ItemView> ___dictionary_0)
            {
                if (!ValidPrerequisites(itemContext, targetItemContext, operation))
                {
                    return;
                }

                Item item = itemContext.Item;
                Item targetItem = targetItemContext.Item;
                ItemAddress itemAddress = item.Parent;
                ItemAddress targetItemAddress = targetItem.Parent;

                if (targetItemAddress == null)
                {
                    return;
                }

                // Repair kits are special
                if (___dictionary_0.TryGetValue(targetItem.Id, out ItemView targetItemView))
                {
                    if (targetItemView.CanInteract(itemContext))
                    {
                        return;
                    }
                }

                // This is the location you're dragging it, including rotation
                LocationInGrid itemToLocation = __instance.CalculateItemLocation(itemContext);

                // Target is a grid because this is the GridView patch, i.e. you're dragging it over a grid
                var targetGridItemAddress = targetItemAddress as GridItemAddress;
                ItemAddress itemToAddress = new GridItemAddress(targetGridItemAddress.Grid, itemToLocation);

                ItemAddress targetToAddress;
                if (itemAddress is GridItemAddress gridItemAddress)
                {
                    LocationInGrid targetToLocation = gridItemAddress.LocationInGrid.Clone();
                    targetToLocation.r = targetGridItemAddress.LocationInGrid.r;

                    targetToAddress = new GridItemAddress(gridItemAddress.Grid, targetToLocation);
                }
                else if (R.SlotItemAddress.Type.IsInstanceOfType(itemAddress))
                {
                    targetToAddress = R.SlotItemAddress.Create(new R.SlotItemAddress(itemAddress).Slot);
                }
                else
                {
                    return;
                }

                // Get the TraderControllerClass
                TraderControllerClass traderControllerClass = __instance.R().TraderController;

                // Check that the destinations won't overlap (Swap won't check this)
                if (!ItemsOverlap(item, itemToAddress, targetItem, targetToAddress))
                {
                    // Try original rotations
                    var result = InteractionsHandlerClass.Swap(item, itemToAddress, targetItem, targetToAddress, traderControllerClass, true);
                    operation = new R.SwapOperation(result).ToGridViewCanAcceptOperation();
                    __result = result.Succeeded;
                    if (result.Succeeded)
                    {
                        return;
                    }
                }

                // If the target is going to a grid, try rotating it. This address is already a new object, safe to modify
                if (targetToAddress is GridItemAddress targetToGridItemAddress)
                {
                    targetToGridItemAddress.LocationInGrid.r = targetToGridItemAddress.LocationInGrid.r == ItemRotation.Horizontal ? ItemRotation.Vertical : ItemRotation.Horizontal;
                    if (!ItemsOverlap(item, itemToAddress, targetItem, targetToAddress))
                    {
                        var result = InteractionsHandlerClass.Swap(item, itemToAddress, targetItem, targetToAddress, traderControllerClass, true);
                        if (result.Succeeded)
                        {
                            // Only save this operation result if it succeeded, otherwise return the non-rotated result from above
                            operation = new R.SwapOperation(result).ToGridViewCanAcceptOperation();
                            __result = true;
                            return;
                        }
                    }
                }
            }
        }

        // Operations signal their completion status by raising events when they are disposed. 
        // The Move operation, for example, builds a list of moved items that are no longer valid for binding, and raises unbind events when it completes successfully
        // Swap does not do that, because spaghetti, so do it here.
        public class SwapOperationRaiseEventsPatch : ModulePatch
        {
            protected override MethodBase GetTargetMethod()
            {
                return AccessTools.Method(R.SwapOperation.Type.GenericTypeArguments[0], "RaiseEvents"); // GClass2813
            }

            [PatchPostfix]
            public static void Postfix(TraderControllerClass controller, CommandStatus status, Item ___Item, Item ___Item1)
            {
                if (status != CommandStatus.Succeed || ___Item == null || ___Item1 == null || controller is not InventoryControllerClass inventoryController)
                {
                    return;
                }

                if (!inventoryController.IsAtBindablePlace(___Item))
                {
                    var result = inventoryController.UnbindItemDirect(___Item, false);
                    if (result.Succeeded)
                    {
                        result.Value.RaiseEvents(controller, CommandStatus.Begin);
                        result.Value.RaiseEvents(controller, CommandStatus.Succeed);
                    }
                }

                if (!inventoryController.IsAtBindablePlace(___Item1))
                {
                    var result = inventoryController.UnbindItemDirect(___Item1, false);
                    if (result.Succeeded)
                    {
                        result.Value.RaiseEvents(controller, CommandStatus.Begin);
                        result.Value.RaiseEvents(controller, CommandStatus.Succeed);
                    }
                }

                if (LastHoveredGridItemView != null && LastHoveredGridItemView.ItemContext != null)
                {
                    LastHoveredGridItemView.OnPointerEnter(new PointerEventData(EventSystem.current));
                }
            }
        }

        public class RememberSwapGridHoverPatch : ModulePatch
        {
            protected override MethodBase GetTargetMethod()
            {
                return AccessTools.Method(typeof(GridItemView), nameof(GridItemView.OnPointerEnter));
            }

            [PatchPostfix]
            public static void Postfix(GridItemView __instance)
            {
                LastHoveredGridItemView = __instance;
            }
        }

        // Called when dragging an item onto an equipment slot
        // Handles any kind of ItemAddress as the target destination (aka where the dragged item came from)
        public class SlotCanAcceptSwapPatch : ModulePatch
        {
            protected override MethodBase GetTargetMethod()
            {
                return AccessTools.Method(typeof(DragItemContext), nameof(DragItemContext.CanAccept));
            }

            [PatchPostfix]
            public static void Postfix(DragItemContext __instance, Slot slot, ItemContextAbstractClass targetItemContext, ref IInventoryEventResult operation, TraderControllerClass itemController, bool simulate, ref bool __result)
            {
                // targetItemContext here is not the target item, it's the *parent* context, i.e. the owner of the slot
                // Do a few more checks
                if (slot.ContainedItem == null || __instance.Item == slot.ContainedItem || slot.ContainedItem.GetAllParentItems().Contains(__instance.Item))
                {
                    return;
                }

                using (var containedContext = targetItemContext.CreateChild(slot.ContainedItem))
                {
                    if (!ValidPrerequisites(__instance, containedContext, operation))
                    {
                        return;
                    }
                }

                var item = __instance.Item;
                var targetItem = slot.ContainedItem;
                var itemToAddress = R.SlotItemAddress.Create(slot);
                var targetToAddress = item.Parent;

                // Repair kits again
                // Don't have access to ItemView to call CanInteract, but repair kits can't go into any slot I'm aware of, so...
                if (item.Template is RepairKitClass)
                {
                    return;
                }

                var result = InteractionsHandlerClass.Swap(item, itemToAddress, targetItem, targetToAddress, itemController, simulate);
                operation = new R.SwapOperation(result).ToGridViewCanAcceptOperation();
                __result = result.Succeeded;
            }
        }

        // The patched method here is called when iterating over all slots to highlight ones that the dragged item can interact with
        // Since swap has no special highlight, I just skip the patch here (minor perf savings, plus makes debugging a million times easier)
        public class DetectGridHighlightPrecheckPatch : ModulePatch
        {
            protected override MethodBase GetTargetMethod()
            {
                return AccessTools.Method(typeof(GridItemView), nameof(GridItemView.method_12));
            }

            [PatchPrefix]
            public static void Prefix()
            {
                InHighlight = true;
            }

            [PatchPostfix]
            public static void Postfix()
            {
                InHighlight = false;
            }
        }

        // The patched method here is called when iterating over all slots to highlight ones that the dragged item can interact with
        // Since swap has no special highlight, I just skip the patch here (minor perf savings, plus makes debugging a million times easier)
        public class DetectSlotHighlightPrecheckPatch : ModulePatch
        {
            protected override MethodBase GetTargetMethod()
            {
                return AccessTools.Method(typeof(SlotView), nameof(SlotView.method_2));

            }

            [PatchPrefix]
            public static void Prefix()
            {
                InHighlight = true;
            }

            [PatchPostfix]
            public static void Postfix()
            {
                InHighlight = false;
            }
        }

        // CanApply, when dealing with containers, eventually calls down into FindPlaceForItem, which calls CheckItemFilter. For reasons,
        // if an item fails the filters, it returns the error "no space", instead of "no action". Try to detect this in order to swap.
        public class DetectFilterForSwapPatch : ModulePatch
        {
            protected override MethodBase GetTargetMethod()
            {
                Type type = PatchConstants.EftTypes.Single(t => t.GetMethod("CheckItemFilter", BindingFlags.Public | BindingFlags.Static) != null); // GClass2524
                return AccessTools.Method(type, "CheckItemFilter");
            }

            [PatchPostfix]
            public static void Postfix(Item item, ref bool __result)
            {
                LastCheckItemFilterId = item.Id;
                LastCheckItemFilterResult = __result;
            }
        }

        public class FixNoGridErrorPatch : ModulePatch
        {
            protected override MethodBase GetTargetMethod()
            {
                Type type = typeof(InteractionsHandlerClass).GetNestedTypes().Single(t => t.GetField("noSpaceError") != null);
                return AccessTools.Method(type, "method_1");
            }

            [PatchPostfix]
            public static void Postfix(IEnumerable<EFT.InventoryLogic.IContainer> containersToPut, ref GStruct414<GInterface339> __result, Error ___noSpaceError, Error ___noActionsError)
            {
                // Since 3.9 EFT handles slots in addition to containers here, they get the wrong error
                if (!containersToPut.Any(c => c is StashGridClass) && __result.Error == ___noSpaceError)
                {
                    __result = new(___noActionsError);
                }
            }
        }

        // When dragging an item around, by default it updates an ItemSpecificationPanel when you drag an item on top of a slot
        // It doesn't do anything when you drag an item from a slot onto some other item elsewhere. But with swap, update the item panel then too.
        public class InspectWindowUpdateStatsOnSwapPatch : ModulePatch
        {
            protected override MethodBase GetTargetMethod()
            {
                return AccessTools.Method(typeof(DraggedItemView), nameof(DraggedItemView.UpdateTargetUnderCursor));
            }

            [PatchPostfix]
            public static void Postfix(DraggedItemView __instance, ItemContextAbstractClass itemUnderCursor)
            {
                if (itemUnderCursor?.Item == __instance.Item)
                {
                    return;
                }

                if (SourceContainer is Component sourceComponent)
                {
                    ItemSpecificationPanel panel = sourceComponent.GetComponentInParent<ItemSpecificationPanel>();
                    if (panel != null)
                    {
                        Slot slot = new R.SlotItemAddress(__instance.ItemAddress).Slot;

                        // DragItemContext must be disposed after using, or its buggy implementation causes an infinite loop / stack overflow
                        using DragItemContext itemUnderCursorContext = itemUnderCursor != null ? new DragItemContext(itemUnderCursor, ItemRotation.Horizontal) : null;
                        panel.method_15(slot, itemUnderCursorContext);
                    }
                }
            }
        }

        public class HideScaryTooltipPatch : ModulePatch
        {
            protected override MethodBase GetTargetMethod()
            {
                return AccessTools.Method(typeof(SimpleTooltip), nameof(SimpleTooltip.ShowInventoryError));
            }

            [PatchPrefix]
            public static bool Prefix(SimpleTooltip __instance, InventoryError error)
            {
                if (error is GridNoRoomError || error is GridSpaceTakenError)
                {
                    __instance.Close();
                    return false;
                }

                return true;
            }
        }

        public class FixAddModFirearmOperationPatch : ModulePatch
        {
            protected override MethodBase GetTargetMethod()
            {
                return AccessTools.Method(typeof(FirearmAddingModState), nameof(FirearmAddingModState.OnModChanged));
            }

            // This is the state machine's "adding mod" state
            // Unpatched, it fires off the success callback before returning to ready state
            // Patched to not be that stupid
            [PatchPrefix]
            public static bool Prefix(
                FirearmAddingModState __instance,
                bool ___bool_0,
                FirearmsAnimator ___firearmsAnimator_0,
                Item ___item_0,
                WeaponManagerClass ___weaponManagerClass,
                Slot ___slot_0,
                Weapon ___weapon_0,
                Callback ___callback_0,
                Player ___player_0,
                Player.FirearmController ___firearmController_0)
            {
                if (___bool_0)
                {
                    return false;
                }
                ___bool_0 = true;
                ___firearmsAnimator_0.SetupMod(false);
                GameObject gameObject = Singleton<PoolManager>.Instance.CreateItem(___item_0, true);
                ___weaponManagerClass.SetupMod(___slot_0, gameObject);
                ___firearmsAnimator_0.Fold(___weapon_0.Folded);
                __instance.State = Player.EOperationState.Finished;

                // Begin change (moved from bottom)
                ___firearmController_0.InitiateOperation<FirearmReadyState>().Start(null);
                __instance.method_5(gameObject);
                // End change

                ___callback_0.Succeed();

                ___player_0.BodyAnimatorCommon.SetFloat(PlayerAnimator.WEAPON_SIZE_MODIFIER_PARAM_HASH, (float)___weapon_0.CalculateCellSize().X);
                ___player_0.UpdateFirstPersonGrip(GripPose.EGripType.Common, ___firearmController_0.HandsHierarchy);

                if (___item_0 is Mod mod && mod.HasLightComponent)
                {
                    ___player_0.SendWeaponLightPacket();
                }

                ___firearmController_0.WeaponModified();

                return false;
            }
        }
    }
}