using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Linq;
using System.Linq.Expressions;
using InABox.Clients;
using InABox.Core;
using PRSClasses;

namespace Comal.Classes
{
    public enum JobRequisitionItemStatus
    {
        NotChecked, // Default
        /// <summary>
        /// All required stock has been received, and is in the correct <see cref="ProductStyle"/>.
        /// </summary>
        /// <remarks>
        /// This can be set even if there are unreceived <see cref="JobRequisitionItemPurchaseOrderItem"/>,
        /// since if we got the stock some other way, we still think of it as allocated.
        /// </remarks>
        Allocated,
        /// <summary>
        /// All required stock has been received, but some is not in the correct <see cref="ProductStyle"/>, meaning a treatment is required.
        /// </summary>
        /// <remarks>
        /// This can be set even if there are unreceived <see cref="JobRequisitionItemPurchaseOrderItem"/>,
        /// since if we got the stock some other way, we still think of it as having the stock allocated.
        /// </remarks>
        TreatmentRequired,
        /// <summary>
        /// The <see cref="JobRequisitionItem.OrderRequired"/> has been set, but there are no <see cref="JobRequisitionItemPurchaseOrderItem"/>s for 
        /// this <see cref="JobRequisitionItem"/>.
        /// </summary>
        OrderRequired,
        /// <summary>
        /// We don't yet have all the stock, and there is at least one unreceived <see cref="JobRequisitionItemPurchaseOrderItem"/> of type
        /// <see cref="JobRequisitionItemPurchaseOrderItemType.Stock"/>.
        /// </summary>
        OnOrder,
        /// <summary>
        /// We don't yet have all the stock, and there is at least one unreceived <see cref="JobRequisitionItemPurchaseOrderItem"/> of type
        /// <see cref="JobRequisitionItemPurchaseOrderItemType.Treatment"/> and none of type <see cref="JobRequisitionItemPurchaseOrderItemType.Stock"/>.
        /// </summary>
        TreatmentOnOrder,

        [Obsolete]
        Received,// Drop
        [Obsolete]
        TreatmentReceived,// Drop

        /// <summary>
        /// The <see cref="JobRequisitionItem"/> has been cancelled, meaning it has a non-empty <see cref="JobRequisitionItem.Cancelled"/>.
        /// </summary>
        Cancelled,
        /// <summary>
        /// The <see cref="JobRequisitionItem/"> has been archived, meaning it has a non-empty <see cref="JobRequisitionItem.Archived"/>.
        /// </summary>
        Archived,

        /// <summary>
        /// The <see cref="JobRequisitionItem/"> has been issued, meaning that it has been allocated, and there are stock movements of type <see cref="StockMovementType.Issue"/> adding up to the correct total.
        /// </summary>
        Issued
    }
    public class JobRequisitionItemTotalQtyFormula : IFormula<JobRequisitionItem, double>
    {
        public Expression<Func<JobRequisitionItem, double>> Value => x => x.Qty;
        public Expression<Func<JobRequisitionItem, double>>[] Modifiers => new Expression<Func<JobRequisitionItem, double>>[] { x => x.Dimensions.Value };
        public FormulaOperator Operator => FormulaOperator.Multiply;
        public FormulaType Type => FormulaType.Virtual;
    }

    public class JobRequisitionItemInStockAggregate : CoreAggregate<JobRequisitionItem, StockMovement, double>
    {
        public override Expression<Func<StockMovement, double>> Aggregate => x => x.Units;

        public override Dictionary<Expression<Func<StockMovement, object>>, Expression<Func<JobRequisitionItem, object>>> Links => new Dictionary<Expression<Func<StockMovement, object>>, Expression<Func<JobRequisitionItem, object>>>
        {
            { x => x.JobRequisitionItem.ID, x => x.ID }
        };

        public override AggregateCalculation Calculation => AggregateCalculation.Sum;
    }
    public class JobRequisitionItemOnOrderAggregate : CoreAggregate<JobRequisitionItem, JobRequisitionItemPurchaseOrderItem, double>
    {
        public override Expression<Func<JobRequisitionItemPurchaseOrderItem, double>> Aggregate => x => x.PurchaseOrderItem.Qty;

        public override Dictionary<Expression<Func<JobRequisitionItemPurchaseOrderItem, object>>, Expression<Func<JobRequisitionItem, object>>> Links => new Dictionary<Expression<Func<JobRequisitionItemPurchaseOrderItem, object>>, Expression<Func<JobRequisitionItem, object>>>
        {
            { x => x.JobRequisitionItem.ID, x => x.ID }
        };

        public override AggregateCalculation Calculation => AggregateCalculation.Sum;

        public override Filter<JobRequisitionItemPurchaseOrderItem>? Filter =>
            new Filter<JobRequisitionItemPurchaseOrderItem>(x => x.PurchaseOrderItem.ReceivedDate).IsEqualTo(null);
    }

    [Caption("Items")]
    [UserTracking(typeof(Job))]
    public class JobRequisitionItem : StockEntity, IRemotable, IPersistent, IOneToMany<JobRequisition>,
        ILicense<ProjectManagementLicense>, IJobMaterial, ISequenceable, IIssues
    {
        [EntityRelationship(DeleteAction.Cascade)]
        [Editable(Editable.Hidden)]
        public JobLink Job { get; set; }

        [EntityRelationship(DeleteAction.Cascade)]
        [Editable(Editable.Hidden)]
        public JobRequisitionLink Requisition { get; set; }

        [EntityRelationship(DeleteAction.SetNull)]
        [EditorSequence(1)]
        [RequiredColumn]
        public override ProductLink Product { get; set; }
        
        [EditorSequence(2)]
        [RequiredColumn]
        public ProductStyleLink Style { get; set; }


        [NullEditor]
        [Obsolete("Replaced with Dimensions", true)]
        public double UnitSize { get; set; }

        [EditorSequence(3)]
        [RequiredColumn]
        [DimensionsEditor(typeof(StockDimensions), AllowEditingUnit = false)]
        public override StockDimensions Dimensions { get; set; }
        
        [EditorSequence(4)]
        [RequiredColumn]
        public double Qty { get; set; }        
        
        [DoubleEditor(Editable = Editable.Hidden)]
        [Formula(typeof(JobRequisitionItemTotalQtyFormula))]
        public double TotalQty { get; set; }
        
        [EditorSequence(5)]
        public double UnitCost { get; set; }

        [EditorSequence(6)]
        [CurrencyEditor(Summary = Summary.Sum)]
        public double TotalCost { get; set; }
        
        [EditorSequence(7)]
        [MemoEditor]
        public string Notes { get; set; }
        
        [EditorSequence(8)]
        public SupplierLink Supplier { get; set; }

        [EnumLookupEditor(typeof(JobRequisitionItemStatus), Editable = Editable.Disabled)]
        [EditorSequence(9)]
        [LoggableProperty]
        [RequiredColumn]
        public JobRequisitionItemStatus Status { get; set; } = JobRequisitionItemStatus.NotChecked;

        /// <summary>
        /// The amount of this requisition item that is currently in stock, which is an aggregate of the <see cref="StockMovement.Units"/> property.
        /// </summary>
        [Aggregate(typeof(JobRequisitionItemInStockAggregate))]
        [DoubleEditor(Editable = Editable.Disabled)]
        [EditorSequence(10)]
        public double InStock { get; set; }

        [Aggregate(typeof(JobRequisitionItemOnOrderAggregate))]
        [DoubleEditor(Editable = Editable.Disabled)]
        [EditorSequence(11)]
        public double OnOrder { get; set; }

        [EntityRelationship(DeleteAction.SetNull)]
        [RequiredColumn]
        [Obsolete("Replaced with JobRequisitionItemPurchaseOrderItem")]
        [NullEditor]
        public PurchaseOrderItemLink PurchaseOrderItem { get; set; }

        [Aggregate(typeof(JobRequisitionItemPurchaseOrderNumberAggregate))]
        [TextBoxEditor(Editable = Editable.Hidden)]
        public string PurchaseOrderNumbers { get; set; }

        [RequiredColumn]
        [EditorSequence(12)]
        public DateTime Cancelled { get; set; } = DateTime.MinValue;

        [RequiredColumn]
        [EditorSequence(13)]
        public DateTime Archived { get; set; } = DateTime.MinValue;

        [RequiredColumn]
        [Obsolete("Replaced with JobRequisitionItemPurchaseOrderItem")]
        [NullEditor]
        public DateTime Ordered { get; set; } = DateTime.MinValue;

        [RequiredColumn]
        [EditorSequence(14)]
        public DateTime OrderRequired { get; set; } = DateTime.MinValue;

        [NullEditor]
        public string Issues { get; set; }

        [NullEditor]
        public long Sequence { get; set; }

        static JobRequisitionItem()
        {
            LinkedProperties.Register<JobRequisitionItem, ProductStyleLink, Guid>(x => x.Product.DefaultInstance.Style, x => x.ID, x => x.Style.ID);
            LinkedProperties.Register<JobRequisitionItem, ProductStyleLink, String>(x => x.Product.DefaultInstance.Style, x => x.Code, x => x.Style.Code);
            LinkedProperties.Register<JobRequisitionItem, ProductStyleLink, String>(x => x.Product.DefaultInstance.Style, x => x.Description, x => x.Style.Description);
            
            LinkedProperties.Register<JobRequisitionItem, ProductInstanceLink, double>(x => x.Product.DefaultInstance, x => x.NettCost,
                x => x.UnitCost);

            StockEntity.LinkStockDimensions<JobRequisitionItem>();
            
        }
        
        private bool bChanging;
        
        protected override void DoPropertyChanged(string name, object? before, object? after)
        {
            if (bChanging)
                return;

            try
            {
                bChanging = true;

                if (name.Equals(nameof(Qty)) && after is double qty)
                    TotalCost = UnitCost * qty;
                
                else if (name.Equals(nameof(UnitCost)) && after is double cost)
                    TotalCost = cost * Qty;

                else if (name.Equals(nameof(TotalCost)) && after is double total)
                {
                    if (Qty == 0)
                        Qty = 1;
                    UnitCost = total / Qty;
                }
            }
            finally
            {
                bChanging = false;
            }
            base.DoPropertyChanged(name, before, after);
        }
        
        public static void UpdateCosts(IEnumerable<JobRequisitionItem> items, Dictionary<String,object?> changes)
        {

            void UpdateValue<TType>(JobRequisitionItem item,Expression<Func<JobRequisitionItem, TType>> property, TType value)
            {
                CoreUtils.MonitorChanges(
                    item, 
                    () => CoreUtils.SetPropertyValue(item, CoreUtils.GetFullPropertyName(property, "."), value),
                    changes
                );
            }
            
            var productids = items.Where(x => x.Product.ID != Guid.Empty).Select(x => x.Product.ID).ToArray();
            MultiQuery query = new MultiQuery();
            query.Add(
                new Filter<SupplierProduct>(x=>x.Product.ID).InList(productids),
                new Columns<SupplierProduct>(x=>x.Product.ID)
                    .Add(x=>x.SupplierLink.ID)
                    .Add(x=>x.Style.ID)
                    .Add(x=>x.Dimensions.UnitSize)
                    .Add(x=>x.Job.ID)
                    .Add(x=>x.SupplierCode)
                    .Add(x=>x.SupplierDescription)
                    .Add(x=>x.CostPrice)
            );
            query.Add(
                new Filter<ProductInstance>(x=>x.Product.ID).InList(productids),
                new Columns<ProductInstance>(x=>x.Product.ID)
                    .Add(x => x.Style.ID)
                    .Add(x => x.Dimensions.UnitSize)
                    .Add(x => x.NettCost)
            );
            query.Query();
                
            foreach (var item in items)
            {
                
                //Check Supplier / Job Specific Pricing
                CoreRow? row = query.Get<SupplierProduct>()?.Rows.FirstOrDefault(r =>
                    (r.Get<SupplierProduct, Guid>(c => c.Product.ID) == item.Product.ID)
                    && (r.Get<SupplierProduct, Guid>(c => c.SupplierLink.ID) == item.Supplier.ID)
                    && (r.Get<SupplierProduct, Guid>(c => c.Style.ID) == item.Style.ID)
                    && (string.Equals(r.Get<SupplierProduct,String>(c=>c.Dimensions.UnitSize),item.Dimensions.UnitSize))
                    && (r.Get<SupplierProduct, Guid>(c => c.Job.ID) == item.Job.ID)
                );
                if (row != null)
                {
                    UpdateValue<double>(item, x => x.UnitCost, row.Get<SupplierProduct, double>(c => c.CostPrice));
                    continue;
                }
                
                // Check Supplier Pricing
                row = query.Get<SupplierProduct>()?.Rows.FirstOrDefault(r =>
                    (r.Get<SupplierProduct, Guid>(c => c.Product.ID) == item.Product.ID)
                    && (r.Get<SupplierProduct, Guid>(c => c.SupplierLink.ID) == item.Supplier.ID)
                    && (r.Get<SupplierProduct, Guid>(c => c.Style.ID) == item.Style.ID)
                    && (string.Equals(r.Get<SupplierProduct,String>(c=>c.Dimensions.UnitSize),item.Dimensions.UnitSize))
                    && (r.Get<SupplierProduct, Guid>(c => c.Job.ID) == Guid.Empty)
                );
                if (row != null)
                {
                    UpdateValue<double>(item, x => x.UnitCost, row.Get<SupplierProduct, double>(c => c.CostPrice));
                    continue;
                }
                
                // Check Specific Product Instance
                row = query.Get<ProductInstance>()?.Rows.FirstOrDefault(r =>
                    (r.Get<ProductInstance, Guid>(c => c.Product.ID) == item.Product.ID)
                    && (r.Get<ProductInstance, Guid>(c => c.Style.ID) == item.Style.ID)
                    && (string.Equals(r.Get<ProductInstance,string>(c => c.Dimensions.UnitSize),item.Dimensions.UnitSize))
                );
                if (row != null)
                    UpdateValue<double>(item, x => x.UnitCost, row.Get<ProductInstance, double>(c => c.NettCost));
                else
                    UpdateValue<double>(item, x => x.UnitCost, 0.0F);

            }
        }
    }

    public class JobRequisitionItemPurchaseOrderNumberAggregate : CoreAggregate<JobRequisitionItem, JobRequisitionItemPurchaseOrderItem, string>
    {
        public override Expression<Func<JobRequisitionItemPurchaseOrderItem, string>> Aggregate => x => x.PurchaseOrderItem.PurchaseOrderLink.PONumber;

        public override Dictionary<Expression<Func<JobRequisitionItemPurchaseOrderItem, object>>, Expression<Func<JobRequisitionItem, object>>> Links { get; } = new Dictionary<Expression<Func<JobRequisitionItemPurchaseOrderItem, object>>, Expression<Func<JobRequisitionItem, object>>>
        {
            { x => x.JobRequisitionItem.ID, x => x.ID }
        };

        public override AggregateCalculation Calculation => AggregateCalculation.Concat;
    }
}