using System;
using System.Collections.Generic;
using System.Linq.Expressions;
using NHibernate.Criterion;
using Tanshu.Accounts.Entities;
using Tanshu.Common.Helpers;
using NHibernate;
using System.Linq;

namespace Tanshu.Accounts.Repository
{
    public class VoucherBI : FluentBasicBase
    {
        public VoucherBI()
            : base()
        { }
        public VoucherBI(bool beginTransaction)
            : base(beginTransaction)
        { }
        public VoucherBI(ISession session)
            : base(session)
        { }
        public VoucherBI(ISession session, bool beginTransaction)
            : base(session, beginTransaction)
        { }

        public IList<Voucher> List(Expression<Func<Voucher, bool>> query)
        {
            return Session.QueryOver<Voucher>()
                .Where(query)
                .List();
        }
        public int? Insert(Voucher voucher)
        {
            var dt = DbValues.Date;
            voucher.SetValue(VoucherFields.CreationDate, dt);
            voucher.SetValue(VoucherFields.LastEditDate, dt);
            voucher.SetValue(VoucherFields.Date, dt);
            voucher.SetValue(VoucherFields.KotID, DbValues.KotID);
            voucher.SetValue(VoucherFields.BillID, voucher.Printed ? DbValues.BillID(voucher.VoucherType) : voucher.KotID);
            Kot addedKot = null;
            foreach (var item in voucher.Kots.Where(item => item.KotID == 0))
            {
                addedKot = item;
                item.Date = dt;
                item.Printed = true;
                item.TableID = voucher.TableID;
                item.User = voucher.User;
                item.Code = DbValues.KotCode;
            }
            UpdateBill(voucher);
            var amount = -1 * voucher.Kots.Sum(x => x.Inventories.Sum(y => y.Amount));
            VoucherSettlementBI.UpdateSettlements(voucher.Settlements, amount);

            Session.Save(voucher);
            return addedKot == null ? (int?)null : addedKot.KotID;
        }
        public int? Update(Voucher voucher)
        {
            var dt = DbValues.Date;
            voucher.SetValue(VoucherFields.LastEditDate, dt);
            if (voucher.Date == null)
            {
                voucher.SetValue(VoucherFields.Date, dt);
                voucher.SetValue(VoucherFields.BillID, DbValues.BillID(voucher.VoucherType));
            }

            Kot addedKot = null;
            foreach (var item in voucher.Kots.Where(item => item.KotID == 0))
            {
                addedKot = item;
                item.Date = dt;
                item.Printed = true;
                item.TableID = voucher.TableID;
                item.User = voucher.User;
                item.Code = DbValues.KotCode;
            }
            UpdateBill(voucher);
            var amount = -1 * voucher.Kots.Sum(x => x.Inventories.Sum(y => y.Amount));
            VoucherSettlementBI.UpdateSettlements(voucher.Settlements, amount);
            Session.Update(voucher);
            return addedKot == null ? (int?)null : addedKot.KotID;
        }

        public Voucher Get(Expression<Func<Voucher, bool>> query)
        {
            var voucher = Session.QueryOver<Voucher>()
                .Where(query)
                .SingleOrDefault();
            NHibernateUtil.Initialize(voucher.Customer);
            NHibernateUtil.Initialize(voucher.Waiter);
            NHibernateUtil.Initialize(voucher.User);
            foreach (var kot in voucher.Kots)
            {
                NHibernateUtil.Initialize(kot);
                NHibernateUtil.Initialize(kot.User);
                foreach (var item in kot.Inventories)
                {
                    NHibernateUtil.Initialize(item);
                    NHibernateUtil.Initialize(item.Product);
                    NHibernateUtil.Initialize(item.Product.ProductGroup);
                    foreach (var inmod in item.InventoryModifier)
                        NHibernateUtil.Initialize(inmod.Modifier);
                }
            }
            foreach (var item in voucher.Settlements)
                NHibernateUtil.Initialize(item);
            return voucher;
        }
        public void Delete(int voucherID)
        {
            var voucher = Session.Get<Voucher>(voucherID);
            Delete(voucher);
        }
        public void Delete(Voucher voucher)
        {
            Session.Delete(voucher);
            using (var ft = new FoodTableBI(Session, false))
                ft.UpdateStatus(voucher.TableID, voucher.VoucherID, null);
        }

        public void VoidBill(int voucherID, string reason)
        {
            var voucher = Session.Get<Voucher>(voucherID);
            voucher.Void = true;
            voucher.VoidReason = reason;
            Session.Save(voucher);
        }

        public int MergeKot(int kotID, FoodTable foodTable)
        {
            var kot = Session.Get<Kot>(kotID);
            var voucher = Session.Get<Voucher>(foodTable.VoucherID);
            voucher.Kots.Add(kot);
            Session.Update(voucher);
            return voucher.VoucherID;
        }
        public int MergeTables(int voucherID, FoodTable foodTable)
        {
            var voucher = Session.Get<Voucher>(foodTable.VoucherID);
            var oldVoucher = Session.Get<Voucher>(voucherID);
            foreach (var kot in oldVoucher.Kots)
                voucher.Kots.Add(kot);
            Session.Update(voucher);
            return voucher.VoucherID;
        }
        public int MergeKot(int kotID, Voucher voucher)
        {
            var kot = Session.Get<Kot>(kotID);
            voucher.Kots.Add(kot);
            Session.Update(voucher);
            return voucher.VoucherID;
        }

        private static void UpdateBill(Voucher voucher)
        {
            switch (voucher.VoucherType)
            {
                case VoucherType.Regular:
                    break;
                case VoucherType.NoCharge:
                    foreach (var item in voucher.Kots.SelectMany(kot => kot.Inventories))
                    {
                        item.ServiceCharge = 0;
                        item.ServiceTax = 0;
                        item.Vat = 0;
                    }
                    break;
                case VoucherType.TakeAway:
                    foreach (var item in voucher.Kots.SelectMany(kot => kot.Inventories))
                    {
                        item.ServiceCharge = 0;
                        item.ServiceTax = 0;
                    }
                    break;
                case VoucherType.Staff:
                    foreach (var item in voucher.Kots.SelectMany(kot => kot.Inventories))
                    {
                        item.ServiceCharge = 0;
                        item.ServiceTax = 0;
                        item.Vat = 0;
                    }
                    break;
            }
        }
    }
}