using Comal.Classes;
using InABox.Clients;
using InABox.Core;
using InABox.DynamicGrid;
using InABox.Wpf;
using InABox.WPF;
using NPOI.SS.Formula.Functions;
using Syncfusion.Data;
using Syncfusion.Data.Extensions;
using Syncfusion.UI.Xaml.Grid;
using System;
using System.Collections;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using Columns = InABox.Core.Columns;
using PRSDesktop.Panels.StockForecast.OrderScreen;
using PRSDimensionUtils;
using Syncfusion.Windows.Shared;

namespace PRSDesktop;

public class StockForecastBreakupKey(Guid jobID, Guid requiID)
{
    public Guid JobID { get; set; } = jobID;

    public Guid RequiID { get; set; } = requiID;

    public override bool Equals(object? obj)
    {
        return obj is StockForecastBreakupKey key && key.JobID == JobID && key.RequiID == RequiID;
    }

    public override int GetHashCode()
    {
        return HashCode.Combine(JobID, RequiID);
    }
}

public class StockForecastOrderData(ProductLink product, ProductStyleLink style, StockDimensions dimensions)
{
    public ProductLink Product { get; set; } = product;

    public ProductStyleLink Style { get; set; } = style;

    public StockDimensions Dimensions { get; set; } = dimensions;

    public double RequiredQuantity { get; set; }

    public class QuantityBreakup(Guid jobID, Guid requiID, string description, double qty)
    {
        // This may be blank, in which case this refers to General Stock.
        public Guid JobID { get; set; } = jobID;

        public Guid JobRequiItemID { get; set; } = requiID;

        public string Description { get; set; } = description;

        public double Quantity { get; set; } = qty;
    }
    
    private List<QuantityBreakup> RequiredQuantities { get; set; } = [];

    public List<QuantityBreakup> GetRequiredQuantities() => RequiredQuantities;
    
    public void SetRequiredQuantity(Guid jobID, Guid requiID, string description, double qty)
    {
        RequiredQuantities.Add(new(jobID, requiID, description,qty));
    }
}

public enum StockForecastOrderingType
{
    StockOrder,
    Breakup
}

public class StockForecastOrderingItemQuantity
{
    public event Action? Changed;

    private double orderTotal;
    public double OrderTotal
    {
        get => orderTotal;
        set
        {
            orderTotal = value;
            Changed?.Invoke();
        }
    }

    public Dictionary<StockForecastBreakupKey, double> Breakups { get; init; } = [];

    private SupplierProduct? _supplierProduct;

    /// <summary>
    /// Indicates the Supplier Product that has been selected for this cell. This comes from the combobox column.
    /// </summary>
    public SupplierProduct? SupplierProduct
    {
        get => _supplierProduct;
        set
        {
            _supplierProduct = value;
            Changed?.Invoke();
        }
    }

    public void DoChanged()
    {
        Changed?.Invoke();
    }

    public double JobTotal => Breakups.Values.Sum();

    public double GetTotal(StockForecastOrderingType type) => type == StockForecastOrderingType.StockOrder
        ? OrderTotal
        : JobTotal;
}

public class StockOrderingItem : BaseObject
{
    [EditorSequence(1)]
    public ProductLink Product { get; set; }

    [EditorSequence(2)]
    public ProductStyleLink Style { get; set; }

    [EditorSequence(3)]
    public StockDimensions Dimensions { get; set; }
    
    [EditorSequence(5)]
    [DoubleEditor]
    public double RequiredQuantity { get; set; }

    [EditorSequence(6)]
    [EnumLookupEditor(typeof(SupplierProductOrderStrategy))]
    public SupplierProductOrderStrategy OrderStrategy { get; set; }

    private Dictionary<StockForecastBreakupKey, double> JobRequiredQuantities { get; set; } = new()
    {
        { new(Guid.Empty, Guid.Empty), 0.0 }
    };
    public Dictionary<StockForecastBreakupKey, double> GetJobRequiredQuantities()
    {
        return JobRequiredQuantities;
    }
    
    public void SetJobRequiredQuantity(Guid jobID, Guid requiID, double requiredQuantity)
    {
        JobRequiredQuantities[new(jobID, requiID)] = requiredQuantity;
    }

    public bool CustomStrategy { get; set; } = false;

    public StockForecastOrderingItemQuantity[] Quantities = [];

    public StockForecastOrderingItemQuantity GetQuantity(int i) => Quantities[i];

    public double GetTotalQuantity(StockForecastOrderingType type) => type == StockForecastOrderingType.StockOrder
        ? Quantities.Sum(x => x.OrderTotal)
        : Quantities.Sum(x => x.JobTotal);

    public double GetRequiredQuantity(StockForecastOrderingType type) => type == StockForecastOrderingType.StockOrder
        ? RequiredQuantity
        : JobRequiredQuantities.Values.Sum();

    public void SetQuantities(StockForecastOrderingItemQuantity[] quantities)
    {
        Quantities = quantities;
    }
}

public class StockForecastOrderingResult(
    SupplierLink supplier,
    List<StockForecastOrderData.QuantityBreakup> breakups,
    StockOrderingItem item,
    double quantity,
    SupplierProduct supplierProduct)
{
    public SupplierLink Supplier { get; set; } = supplier;

    public StockOrderingItem Item { get; set; } = item;

    public SupplierProduct SupplierProduct { get; set; } = supplierProduct;

    public double Quantity { get; set; } = quantity;

    public List<StockForecastOrderData.QuantityBreakup> Breakups { get; set; } = breakups;
}

public enum StockForecastOrderingStrategy
{
    PerProduct,
    Exact,
    RoundUp,
    LowestUnitPrice,
    LowestOverallPrice,
    LowestOverstock
}

public class StockForecastOrderingGrid : DynamicItemsListGrid<StockOrderingItem>, ISpecificGrid
{
    #region Internal Data + Caches

    private List<SupplierProduct> SupplierProducts = [];
    private SupplierLink[] Suppliers = [];

    private DynamicActionColumn[] SupplierProductColumns = [];
    private DynamicActionColumn[] QuantityColumns = [];
    private DynamicActionColumn[] CostColumns = [];

    private readonly Dictionary<Guid, Job> JobDetails = [];
    private readonly Dictionary<Guid, JobRequisitionItem> JobRequiDetails = [];

    #endregion

    private static BitmapImage _warning = PRSDesktop.Resources.warning.AsBitmapImage();

    #region Public Properties

    public IList<StockForecastOrderData> OrderData { get; set; }

    private StockForecastOrderingType _orderType = StockForecastOrderingType.Breakup;
    public StockForecastOrderingType OrderType
    {
        get => _orderType;
        set
        {
            if(_orderType != value)
            {
                _orderType = value;
                if (OrderData != null)
                {
                    CalculateQuantities(true);
                    UIComponent.UpdateOrderType(OrderType);
                    foreach(var control in QuantityControls)
                    {
                        control.UpdateControl(OrderType);
                    }

                    Refresh(true, true);
                }
            }
        }
    }

    private StockForecastOrderingStrategy orderStrategy;
    public StockForecastOrderingStrategy OrderStrategy
    {
        get => orderStrategy;
        set
        {
            orderStrategy = value;
            if (OrderData != null)
            {
                foreach (var item in Items)
                {
                    item.OrderStrategy = CastOrderStrategyToProductOrderStrategy(value, item.Product.OrderStrategy);
                    item.CustomStrategy = false;
                }
                CalculateQuantities(false);
                Refresh(false, true);
            }
        }
    }

    public double TotalQuantity => Items.Sum(x => x.GetTotalQuantity(OrderType));
    public IEnumerable<StockForecastOrderingResult> Results
    {
        get
        {
            for(int i = 0; i < Suppliers.Length; ++i)
            {
                var supplier = Suppliers[i];
                foreach(var item in Items)
                {
                    var qty = item.GetQuantity(i);
                    if (qty.SupplierProduct is null)
                    {
                        continue;
                    }

                    if(OrderType == StockForecastOrderingType.StockOrder && qty.OrderTotal > 0)
                    {
                        yield return new(supplier, new(), item, qty.OrderTotal, qty.SupplierProduct);
                    }
                    else if(qty.OrderTotal > 0)
                    {
                        var breakups = new List<StockForecastOrderData.QuantityBreakup>();
                        foreach(var (key, q) in qty.Breakups)
                        {
                            // Check JobID because we are to skip the empty job (this is just the difference between all the allocations and the quantity on the PO).
                            if(q > 0 && key.JobID != Guid.Empty)
                            {
                                breakups.Add(new(key.JobID, key.RequiID, "", q));
                            }
                        }
                        yield return new(supplier, breakups, item, qty.OrderTotal, qty.SupplierProduct);
                    }
                }
            }
        }
    }

    #endregion

    public StockForecastOrderingGrid()
    {
        HiddenColumns.Add(x => x.Product.Image.ID);
    }

    private static SupplierProductOrderStrategy CastOrderStrategyToProductOrderStrategy(StockForecastOrderingStrategy strategy, SupplierProductOrderStrategy defaultValue)
    {
        return strategy switch
        {
            StockForecastOrderingStrategy.Exact => SupplierProductOrderStrategy.Exact,
            StockForecastOrderingStrategy.LowestOverallPrice => SupplierProductOrderStrategy
                .LowestOverallPrice,
            StockForecastOrderingStrategy.LowestUnitPrice => SupplierProductOrderStrategy.LowestUnitPrice,
            StockForecastOrderingStrategy.LowestOverstock => SupplierProductOrderStrategy.LowestOverstock,
            StockForecastOrderingStrategy.RoundUp => SupplierProductOrderStrategy.RoundUp,
            StockForecastOrderingStrategy.PerProduct or _ => defaultValue
        };
    }


    #region UI Component

    private Component? _uiComponent;
    private Component UIComponent
    {
        get
        {
            _uiComponent ??= new Component(this);
            return _uiComponent;
        }
    }
    protected override IDynamicGridUIComponent<StockOrderingItem> CreateUIComponent()
    {
        return UIComponent;
    }
    private class Component : DynamicGridGridUIComponent<StockOrderingItem>
    {
        private StockForecastOrderingGrid Grid;

        public Component(StockForecastOrderingGrid grid)
        {
            Parent = grid;
            Grid = grid;

            UpdateOrderType(grid.OrderType);
        }

        public void UpdateOrderType(StockForecastOrderingType type)
        {
            DataGrid.FrozenColumnCount = 8;
        }

        protected override Brush? GetCellSelectionBackgroundBrush()
        {
            return null;
        }

        protected override Brush? GetCellBackground(CoreRow row, DynamicColumnBase column)
        {
            var item = Grid.LoadItem(row);
            if(column is DynamicActionColumn ac)
            {
                var qIdx = Grid.QuantityColumns.IndexOf(ac);
                var idx = Math.Max(qIdx, Grid.CostColumns.IndexOf(ac));
                if(idx != -1)
                {
                    var supplierProduct = item.GetQuantity(idx).SupplierProduct;
                    return supplierProduct is null 
                        ? Brushes.Gainsboro 
                        : Brushes.WhiteSmoke;
                }
            }
            return base.GetCellBackground(row, column);
        }
    }

    #endregion

    private bool _observing = true;
    private void SetObserving(bool observing)
    {
        _observing = observing;
    }
    protected override void Changed()
    {
        if (_observing)
        {
            base.Changed();
        }
    }

    protected override void DoReconfigure(DynamicGridOptions options)
    {
        options.Clear();
        options.FilterRows = true; 
    }

    private bool _loadedData = false;
    private void LoadData()
    {
        var supplierProductColumns = Columns.None<SupplierProduct>().Add(x => x.ID)
            .Add(x => x.SupplierLink.ID)
            .Add(x => x.Product.ID)
            .Add(x => x.Style.ID)
            .Add(x => x.Style.Code)
            .Add(x => x.Job.ID)
            .Add(x => x.Job.JobNumber)
            .Add(x => x.ForeignCurrencyPrice)
            .Add(x => x.CostPrice)
            .AddDimensionsColumns(x => x.Dimensions)
            .Add(x => x.SupplierLink.Code);

        SupplierProducts = Client.Query(
            new Filter<SupplierProduct>(x => x.Product.ID).InList(OrderData.Select(x => x.Product.ID).ToArray())
                .And(x => x.SupplierLink.ID).IsNotEqualTo(Guid.Empty),
            supplierProductColumns,
            new SortOrder<SupplierProduct>(x => x.SupplierLink.Code))
            .ToList<SupplierProduct>();

        Suppliers = SupplierProducts.Select(x => x.SupplierLink).DistinctBy(x => x.ID).ToArray();

        CalculateQuantities(true);

        _loadedData = true;
    }

    private StockForecastOrderingItemQuantity CreateQuantity(int itemIdx)
    {
        var qty = new StockForecastOrderingItemQuantity();
        qty.Changed += () =>
        {
            if (!_observing) return;

            var row = Data.Rows[itemIdx];
            InvalidateRow(row);
            DoChanged();
        };
        return qty;
    }

    private SupplierProduct? CalculateSupplierProduct(StockOrderingItem item, int supplierIdx)
    {
        var supplierProducts = string.IsNullOrWhiteSpace(item.Dimensions.Unit.Conversion)
            ? SupplierProducts.Where(x => x.Dimensions.Equals(item.Dimensions))
            : SupplierProducts;
        var supplierProduct = SelectSupplierProduct(supplierProducts.Where(x => x.Product.ID == item.Product.ID && x.Style.ID == item.Style.ID && x.SupplierLink.ID == Suppliers[supplierIdx].ID), item);

        var qty = item.GetQuantity(supplierIdx);
        qty.SupplierProduct = supplierProduct;
        qty.OrderTotal = 0;
        qty.Breakups.Clear();
        foreach(var id in item.GetJobRequiredQuantities().Keys)
        {
            qty.Breakups[id] = 0;
        }

        return supplierProduct;
    }

    private void SetSupplierProduct(StockOrderingItem item, SupplierProduct supplierProduct)
    {
        var supplierIdx = Suppliers.WithIndex()
            .FirstOrDefault(x => x.Value.ID == supplierProduct.SupplierLink.ID, new KeyValuePair<int, SupplierLink>(-1, null)).Key;
        if(supplierIdx != -1)
        {
            var qty = item.GetQuantity(supplierIdx);
            if(OrderType == StockForecastOrderingType.Breakup)
            {
                qty.Breakups.Clear();
                foreach(var (id, q) in item.GetJobRequiredQuantities())
                {
                    qty.Breakups[id] = q;
                }
            }
            qty.OrderTotal = GetRequiredQuantity(item, supplierProduct);
        }
    }

    private void CalculateSupplierProduct(StockOrderingItem item)
    {
        var selectedSupplierProducts = new List<SupplierProduct>();
        for(int i = 0; i < Suppliers.Length; ++i)
        {
            var supplierProduct = CalculateSupplierProduct(item, i);
            if(supplierProduct is not null)
            {
                selectedSupplierProducts.Add(supplierProduct);
            }
        }
        var selectedSupplierProduct = SelectSupplierProduct(selectedSupplierProducts, item);
        if(selectedSupplierProduct is not null)
        {
            SetSupplierProduct(item, selectedSupplierProduct);
        }
    }

    private void CalculateQuantities(bool recreateItems)
    {
        SetObserving(false);

        if (recreateItems)
        {
            Items.Clear();
            foreach(var dataItem in OrderData)
            {
                var item = new StockOrderingItem();
                item.Product.CopyFrom(dataItem.Product);
                item.Style.CopyFrom(dataItem.Style);
                item.Dimensions.CopyFrom(dataItem.Dimensions);
                item.OrderStrategy = CastOrderStrategyToProductOrderStrategy(OrderStrategy, item.Product.OrderStrategy);
                item.RequiredQuantity = dataItem.RequiredQuantity;
                foreach(var breakup in dataItem.GetRequiredQuantities())
                {
                    item.SetJobRequiredQuantity(breakup.JobID, breakup.JobRequiItemID, breakup.Quantity);
                }
                Items.Add(item);
            }
        }

        foreach(var (itemIdx, item) in Items.WithIndex())
        {
            var quantities = new StockForecastOrderingItemQuantity[Suppliers.Length];
            for(int i = 0; i < Suppliers.Length; ++i)
            {
                quantities[i] = CreateQuantity(itemIdx);
            }

            item.SetQuantities(quantities);
        }

        foreach(var item in Items)
        {
            CalculateSupplierProduct(item);
        }
        SetObserving(true);
        DoChanged();
    }

    #region Order Strategy

    private double CalculateSupplierProductRequiredQuantity(StockOrderingItem item, SupplierProduct supplierProduct)
    {
        var supplierIdx = Suppliers.WithIndex().FirstOrDefault(x => x.Value.ID == supplierProduct.SupplierLink.ID).Key;
        var qty = item.GetQuantity(supplierIdx);
        var req = OrderType == StockForecastOrderingType.StockOrder ? item.RequiredQuantity : qty.Breakups.Sum(x => x.Value);

        var d = new StockDimensions();
        d.CopyFrom(supplierProduct.Dimensions);
        var result = DimensionUtils.ConvertDimensions(d, 1.0, (f,c) => Client.Query(f,c));
        req = Math.Ceiling(req / result);
        return req;
    }

    private SupplierProduct? SelectSupplierProduct(IEnumerable<SupplierProduct> supplierProducts, StockOrderingItem item)
    {
        double DimensionsRatio(SupplierProduct x)
        {
            return item.Dimensions.Value / (x.Dimensions.Value.IsEffectivelyEqual(0.0) ? (item.Dimensions.Value.IsEffectivelyEqual(0.0) ? 1.0 : item.Dimensions.Value) : x.Dimensions.Value);
        }
        switch (item.OrderStrategy)
        {
            case SupplierProductOrderStrategy.Exact:
            case SupplierProductOrderStrategy.RoundUp:
                return supplierProducts.Where(x => x.Dimensions.Equals(item.Dimensions))
                           .MinBy(x => x.CostPrice);
            
            case SupplierProductOrderStrategy.LowestOverallPrice:
                return supplierProducts.MinBy(x => x.CostPrice * Math.Ceiling(CalculateSupplierProductRequiredQuantity(item, x) * DimensionsRatio(x)));

            case SupplierProductOrderStrategy.LowestUnitPrice:
                return supplierProducts.MinBy(x => x.CostPrice * DimensionsRatio(x));
            
            case SupplierProductOrderStrategy.LowestOverstock:
                return supplierProducts.MinBy(x => x.Dimensions.Value * Math.Ceiling(CalculateSupplierProductRequiredQuantity(item, x) * DimensionsRatio(x)));
                
            default:
                return null;
        }
    }

    private double GetRequiredQuantity(StockOrderingItem item, SupplierProduct supplierProduct)
    {
        var requiredQuantity = CalculateSupplierProductRequiredQuantity(item, supplierProduct);

        double DimensionsRatio(SupplierProduct x)
        {
            return item.Dimensions.Value / (x.Dimensions.Value.IsEffectivelyEqual(0.0) ? (item.Dimensions.Value.IsEffectivelyEqual(0.0) ? 1.0 : item.Dimensions.Value) : x.Dimensions.Value);
        }

        var _strategy = item.CustomStrategy
            ? SupplierProductOrderStrategy.LowestOverstock
            : item.OrderStrategy;
        
        switch (_strategy)
        {
            case SupplierProductOrderStrategy.Exact:
                return requiredQuantity;
            case SupplierProductOrderStrategy.RoundUp:
                return Math.Ceiling(requiredQuantity);
            case SupplierProductOrderStrategy.LowestOverallPrice:
            case SupplierProductOrderStrategy.LowestUnitPrice:
            case SupplierProductOrderStrategy.LowestOverstock:
                return Math.Ceiling(requiredQuantity * DimensionsRatio(supplierProduct));
            default:
                return 0.0;
        }
    }

    #endregion

    private bool _loadedColumns = false;
    protected override DynamicGridColumns LoadColumns()
    {
        if (!_loadedData)
        {
            LoadData();
        }

        var columns = new DynamicGridColumns();
        columns.Add<StockOrderingItem, string>(x => x.Product.Code, 120, "Product Code", "", Alignment.MiddleCenter);
        columns.Add<StockOrderingItem, string>(x => x.Product.Name, 0, "Product Name", "", Alignment.MiddleLeft);
        columns.Add<StockOrderingItem, string>(x => x.Dimensions.UnitSize, 80, "Size", "", Alignment.MiddleCenter);
        columns.Add<StockOrderingItem, string>(x => x.Style.Code, 80, "Style", "", Alignment.MiddleCenter);
        columns.Add<StockOrderingItem, double>(x => x.RequiredQuantity, 80, "Required", "", Alignment.MiddleCenter);

        if (!_loadedColumns)
        {
            ActionColumns.Clear();

            ActionColumns.Add(new DynamicImageColumn(Warning_Image) { Position = DynamicActionColumnPosition.Start });
            ActionColumns.Add(new DynamicImagePreviewColumn<StockOrderingItem>(x => x.Product.Image) { Position = DynamicActionColumnPosition.Start });

            ActionColumns.Add(new DynamicTemplateColumn(row =>
            {
                var item = LoadItem(row);

                var box = new ComboBox();
                box.ItemsSource = Enum.GetValues<SupplierProductOrderStrategy>()
                    .Select(x => new KeyValuePair<SupplierProductOrderStrategy, string>(x, CoreUtils.Neatify(x.ToString())));
                box.DisplayMemberPath = "Value";
                box.SelectedValuePath = "Key";
                box.SelectedValue = item.CustomStrategy ? null : item.OrderStrategy;
                box.SelectionChanged += (o, e) =>
                {
                    if (box.SelectedValue is not SupplierProductOrderStrategy strategy) return;
                    item.OrderStrategy = strategy;
                    item.CustomStrategy = false;
                    CalculateSupplierProduct(item);
                    InvalidateRow(row);
                };
                box.Margin = new Thickness(2);
                box.VerticalContentAlignment = VerticalAlignment.Center;
                return box;
            })
            {
                HeaderText = "Order Strategy.",
                Width = 140
            });

            SupplierProductColumns = new DynamicActionColumn[Suppliers.Length];
            QuantityColumns = new DynamicActionColumn[Suppliers.Length];
            CostColumns = new DynamicActionColumn[Suppliers.Length];
            QuantityControls.Clear();

            for(int i = 0; i < Suppliers.Length; ++i)
            {
                InitialiseSupplierColumn(i);
            }

            ActionColumns.Add(new DynamicMenuColumn(BuildMenu));

            _loadedColumns = true;
        }

        return columns;
    }

    private void EditSupplierProductGrid(DynamicGrid<SupplierProduct> grid)
    {
        grid.OnCustomiseEditor += (sender, items, column, editor) =>
        {
            if(new Column<SupplierProduct>(x => x.SupplierLink.ID).IsEqualTo(column.ColumnName)
                || new Column<SupplierProduct>(x => x.Product.ID).IsEqualTo(column.ColumnName)
                || new Column<SupplierProduct>(x => x.Style.ID).IsEqualTo(column.ColumnName))
            {
                editor.Editable = editor.Editable.Combine(Editable.Disabled);
            }
        };
    }

    private void BuildMenu(DynamicMenuColumn column, CoreRow? row)
    {
        if (row is null) return;

        column.AddItem("New Supplier", null, row =>
        {
            if (row is null) return;

            var selection = new MultiSelectDialog<Supplier>(
                new Filter<Supplier>(x => x.ID).NotInList(Suppliers.Select(x => x.ID).ToArray()),
                Columns.None<Supplier>().Add(x => x.ID).Add(x => x.Code), multiselect: false);
            if (selection.ShowDialog() != true)
            {
                return;
            }

            var supplier = selection.Data().Rows.First().ToObject<Supplier>();
            var orderingItem = LoadItem(row);

            var supplierProduct = new SupplierProduct();
            supplierProduct.Product.CopyFrom(orderingItem.Product);
            supplierProduct.Style.CopyFrom(orderingItem.Style);
            supplierProduct.Dimensions.CopyFrom(orderingItem.Dimensions);
            supplierProduct.SupplierLink.CopyFrom(supplier);

            if (DynamicGridUtils.EditEntity(supplierProduct, customiseGrid: EditSupplierProductGrid))
            {
                SupplierProducts.Add(supplierProduct);
                var newSuppliers = new SupplierLink[Suppliers.Length + 1];
                var newIdx = Suppliers.Length;

                for (int i = 0; i < Suppliers.Length; i++)
                {
                    newSuppliers[i] = Suppliers[i];
                }
                newSuppliers[newIdx] = supplierProduct.SupplierLink;

                foreach (var (itemIdx, item) in Items.WithIndex())
                {
                    var quantities = new StockForecastOrderingItemQuantity[newSuppliers.Length];
                    for (int i = 0; i < Suppliers.Length; ++i)
                    {
                        quantities[i] = item.GetQuantity(i);
                    }
                    var newQty = CreateQuantity(itemIdx);

                    quantities[newIdx] = newQty;
                    if(OrderType == StockForecastOrderingType.StockOrder)
                    {
                        newQty.OrderTotal = 0;
                    }
                    else
                    {
                        newQty.OrderTotal = 0;
                        foreach(var id in item.GetJobRequiredQuantities().Keys)
                        {
                            newQty.Breakups[id] = 0;
                        }
                    }
                    item.SetQuantities(quantities);
                }
                Suppliers = newSuppliers;
                foreach (var item in Items)
                {
                    CalculateSupplierProduct(item, newIdx);
                }

                _loadedColumns = false;
                Refresh(true, true);
            }
        });
    }

    private BitmapImage? Warning_Image(CoreRow? row)
    {
        if (row is null) return _warning;

        var item = LoadItem(row);
        if(item.GetTotalQuantity(OrderType) < item.RequiredQuantity)
        {
            return _warning;
        }
        else
        {
            return null;
        }
    }

    protected override void ConfigureColumnGroups()
    {
        for(int idx = 0; idx < Suppliers.Length; ++idx)
        {
            GetColumnGrouping().AddGroup(Suppliers[idx].Code, SupplierProductColumns[idx], CostColumns[idx]);
        }
    }

    #region Job Data Cache

    private void LoadJobData(IEnumerable<Guid> ids)
    {
        var neededIDs = ids.Where(x => x != Guid.Empty && !JobDetails.ContainsKey(x)).ToArray();
        if(neededIDs.Length > 0)
        {
            var details = Client.Query(
                new Filter<Job>(x => x.ID).InList(neededIDs),
                Columns.None<Job>().Add(x => x.ID)
                    .Add(x => x.JobNumber)
                    .Add(x => x.Name));
            foreach(var job in details.ToObjects<Job>())
            {
                JobDetails[job.ID] = job;
            }
        }
    }
    private void LoadJobRequiData(IEnumerable<Guid> ids)
    {
        var neededIDs = ids.Where(x => x != Guid.Empty && !JobRequiDetails.ContainsKey(x)).ToArray();
        if(neededIDs.Length > 0)
        {
            var details = Client.Query(
                new Filter<JobRequisitionItem>(x => x.ID).InList(neededIDs),
                Columns.None<JobRequisitionItem>().Add(x => x.ID)
                    .Add(x => x.Requisition.Number)
                    .Add(x => x.Requisition.Description));
            foreach(var requi in details.ToObjects<JobRequisitionItem>())
            {
                JobRequiDetails[requi.ID] = requi;
            }
        }
    }

    #endregion

    private class QuantityControl : ContentControl
    {
        private readonly StockOrderingItem Item;
        private readonly int SupplierIndex;
        private readonly StockForecastOrderingGrid Parent;

        public QuantityControl(StockForecastOrderingGrid parent, StockOrderingItem item, int supplierIndex, StockForecastOrderingType mode)
        {
            Parent = parent;
            Item = item;
            SupplierIndex = supplierIndex;

            UpdateControl(mode);
        }

        public void UpdateControl(StockForecastOrderingType mode)
        {
            // If no supplier product has been selected for this cell, we can't allow the user to select a quantity.
            var supplierProduct = Item.GetQuantity(SupplierIndex).SupplierProduct;
            if(supplierProduct is null)
            {
                Content = null;
                return;
            }

            if(mode == StockForecastOrderingType.StockOrder)
            {
                var editor = new DoubleTextBox
                {
                    VerticalAlignment = VerticalAlignment.Stretch,
                    HorizontalAlignment = HorizontalAlignment.Stretch,
                    Background = new SolidColorBrush(Colors.LightYellow),
                    BorderThickness = new Thickness(0.0),
                    MinValue = 0.0,
                    Value = Item.GetQuantity(SupplierIndex).OrderTotal
                };
                editor.ValueChanged += (o, e) =>
                {
                    Item.GetQuantity(SupplierIndex).OrderTotal = editor.Value ?? default;
                };
                Content = editor;
            }
            else if(mode == StockForecastOrderingType.Breakup)
            {
                var grid = new Grid();
                grid.ColumnDefinitions.Add(new ColumnDefinition { Width = new GridLength(1, GridUnitType.Star) });
                grid.ColumnDefinitions.Add(new ColumnDefinition { Width = new GridLength(30) });

                var _breakups = Item.GetQuantity(SupplierIndex).Breakups.Sum(x => x.Value);
                
                var editor = new DoubleTextBox
                {
                    VerticalAlignment = VerticalAlignment.Stretch,
                    HorizontalAlignment = HorizontalAlignment.Stretch,
                    VerticalContentAlignment = VerticalAlignment.Center,
                    HorizontalContentAlignment = HorizontalAlignment.Center,
                    Background = new SolidColorBrush(Colors.WhiteSmoke),
                    BorderThickness = new Thickness(0.0),
                    Value = Item.GetQuantity(SupplierIndex).OrderTotal,
                    IsReadOnly = true,
                    Focusable = false,
                };
                Grid.SetColumn(editor, 0);
                grid.Children.Add(editor);

                var btn = new Button
                {
                    VerticalAlignment = VerticalAlignment.Stretch,
                    VerticalContentAlignment = VerticalAlignment.Center,
                    HorizontalAlignment = HorizontalAlignment.Stretch,
                    Content = "..",
                    Margin = new Thickness(1),
                    Focusable = false
                };
                btn.SetValue(Grid.ColumnProperty, 1);
                btn.SetValue(Grid.RowProperty, 0);
                btn.Click += (o, e) =>
                {
                    var qty = Item.GetQuantity(SupplierIndex);
                    
                    Parent.LoadJobData(qty.Breakups.Keys.Select(x => x.JobID));
                    Parent.LoadJobRequiData(qty.Breakups.Keys.Select(x => x.RequiID));

                    var items = qty.Breakups.Select(x =>
                    {
                        var item = new StockForecastOrderingJobItem
                        {
                            JobID = x.Key.JobID,
                            JobRequiID = x.Key.RequiID,
                            RequiredQuantity = Item.GetJobRequiredQuantities().GetValueOrDefault(x.Key),
                            Quantity = x.Value
                        };
                        if(item.JobID == Guid.Empty)
                        {
                            item.Description = "General Stock";
                        }
                        else if(Parent.JobDetails.TryGetValue(item.JobID, out var job))
                        {
                            if(Parent.JobRequiDetails.TryGetValue(item.JobRequiID, out var requi))
                            {
                                item.Description = $"{job.JobNumber}: Requi #{requi.Requisition.Number} ({requi.Requisition.Description})";
                            }
                            else
                            {
                                item.Description = $"{job.JobNumber}: {job.Name}";
                            }
                        }
                        return item;
                    }).ToList();

                    var genitem = items.FirstOrDefault(x =>
                        x.JobID == Guid.Empty && x.JobRequiID == Guid.Empty);
                    if (genitem == null)
                    {
                        genitem = new StockForecastOrderingJobItem
                        {
                            Description = "General Stock",
                            JobID = Guid.Empty,
                            JobRequiID = Guid.Empty
                        };
                        items.Insert(0, genitem);
                    }
                    else
                    {
                        items.Remove(genitem);
                        items.Insert(0, genitem);
                    }

                    var window = new StockForecastOrderJobScreen();
                    window.Items = items;
                    if(window.ShowDialog() == true)
                    {
                        foreach(var item in items)
                        {
                            qty.Breakups[new(item.JobID, item.JobRequiID)] = item.Quantity;
                        }
                        qty.DoChanged();

                        var req = Parent.GetRequiredQuantity(Item, supplierProduct);

                        editor.Value = req;
                        qty.OrderTotal = req;
                    }
                };
                grid.Children.Add(btn);

                Content = grid;
            }
        }
    }

    private List<QuantityControl> QuantityControls = [];

    private void InitialiseSupplierColumn(int idx)
    {
        var contextMenuFunc = (CoreRow[]? rows) =>
        {
            var row = rows?.FirstOrDefault();
            if (row is null) return null;

            var item = LoadItem(row);

            var menu = new ContextMenu();
            menu.AddItem("Create Supplier Product", null, new Tuple<StockOrderingItem, int>(item, idx), CreateSupplierProduct_Click);
            return menu;
        };

        var qtyColumn = new Tuple<DynamicActionColumn, QuantityControl?>(null!, null);
        SupplierProductColumns[idx] = new DynamicTemplateColumn(row =>
        {
            var instance = LoadItem(row);

            var comboBox = new ComboBox();
            comboBox.Tag = idx;

            var supplierProducts = string.IsNullOrWhiteSpace(instance.Dimensions.Unit.Conversion)
                ? SupplierProducts.Where(x => x.Dimensions.Equals(instance.Dimensions))
                : SupplierProducts;

            var items = supplierProducts.Where(x => x.SupplierLink.ID == Suppliers[idx].ID && x.Product.ID == instance.Product.ID)
                .Select(x => new KeyValuePair<SupplierProduct?, string>(x, x.Job.ID == Guid.Empty ? x.Dimensions.UnitSize : $"Job {x.Job.JobNumber}: {x.Dimensions.UnitSize}"));
            if (items.Any())
                items = items.Prepend(new KeyValuePair<SupplierProduct?, string>(null, ""));
            comboBox.SelectedValuePath = "Key";

            comboBox.ItemsSource = items.ToArray();
            comboBox.DisplayMemberPath = "Value";

            var qty = instance.GetQuantity(idx);

            comboBox.Bind(ComboBox.SelectedValueProperty, qty, x => x.SupplierProduct);
            comboBox.SelectionChanged += (o, e) =>
            {
                var box = o as ComboBox; 
                instance.CustomStrategy = true;
                var _item = LoadItem(row);
                var _product = ((o as ComboBox)?.SelectedValue as SupplierProduct ?? new SupplierProduct());
                qty.OrderTotal = GetRequiredQuantity(_item, _product);
                
                InvalidateRow(row);
            };

            comboBox.VerticalContentAlignment = VerticalAlignment.Center;
            comboBox.Margin = new Thickness(2);
            if(!items.Any())
                comboBox.IsEnabled = false;

            return comboBox;
        })
        {
            HeaderText = "U.O.M.",
            Width = 80
        };
        
        QuantityColumns[idx] = new DynamicTemplateColumn(row =>
        {
            var instance = LoadItem(row);
            var control = new QuantityControl(this, instance, idx, OrderType);
            QuantityControls.Add(control);
            return control;
        })
        {
            HeaderText = "Qty.",
            Width = 80,
            ContextMenu = contextMenuFunc
        };
        
        CostColumns[idx] = new DynamicTextColumn(row =>
        {
            if(row is null)
            {
                return "Cost";
            }

            var instance = LoadItem(row);
            var qty = instance.GetQuantity(idx);
            if(qty.SupplierProduct is not null)
            {
                return $"{qty.OrderTotal * qty.SupplierProduct.CostPrice:C2}";
            }
            else
            {
                return "";
            }
        })
        {
            HeaderText = "Cost",
            Width = 80,
            ContextMenu = contextMenuFunc,
            GetSummary = () =>
            {
                return new DynamicGridCustomSummary((rows) => Cost_Aggregate(idx, rows), "C2");
            }
        };
        ActionColumns.Add(SupplierProductColumns[idx]);
        ActionColumns.Add(QuantityColumns[idx]);
        ActionColumns.Add(CostColumns[idx]);
    }

    private double Cost_Aggregate(int supplierIdx, IEnumerable<CoreRow> rows)
    {
        return rows.Sum(row =>
        {
            var item = LoadItem(row);
            var qty = item.GetQuantity(supplierIdx);
            if(qty.SupplierProduct is not null)
            {
                return qty.OrderTotal * qty.SupplierProduct.CostPrice;
            }
            else
            {
                return 0;
            }
        });
    }

    private void CreateSupplierProduct_Click(Tuple<StockOrderingItem, int> tuple)
    {
        var (item, supplierIdx) = tuple;

        var supplierProduct = new SupplierProduct();
        supplierProduct.Product.CopyFrom(item.Product);
        supplierProduct.Style.CopyFrom(item.Style);
        supplierProduct.Dimensions.CopyFrom(item.Dimensions);
        supplierProduct.SupplierLink.CopyFrom(Suppliers[supplierIdx]);

        if (DynamicGridUtils.EditEntity(supplierProduct, customiseGrid: EditSupplierProductGrid))
        {
            SupplierProducts.Add(supplierProduct);
            var qty = item.GetQuantity(supplierIdx);
            if(qty.SupplierProduct is null)
            {
                var hasSelected = item.Quantities.Any(x => x.SupplierProduct is not null);
                var sp = CalculateSupplierProduct(item, supplierIdx);
                if(!hasSelected && sp is not null)
                {
                    SetSupplierProduct(item, sp);
                }
            }
            InvalidateGrid();
        }
    }
}