using System;
using System.Collections.Generic;
using Tanshu.Accounts.Contracts;
using Tanshu.Accounts.Entities;
using Tanshu.Accounts.Entities.Auth;
using NHibernate;
using System.Linq;

namespace Tanshu.Accounts.Repository
{
    public static class VoucherBI
    {
        static public BillInventory GetDefaultSaleBillItem(int productID)
        {
            Product product;
            using (var session = SessionManager.Session)
            {
                product = session.Get<Product>(productID);
                return new BillInventory()
                {
                    ProductID = product.ProductID,
                    Name = product.Units == string.Empty ? product.Name : product.Name + " (" + product.Units + ")",
                    Price = product.SalePrice,
                    Tax = product.Tax.Rate,
                    ServiceCharge = product.ServiceCharge,
                    Discount = 0,
                    Printed = false,
                    Quantity = 1,
                };
            }
        }
        static public decimal GetProductDiscountLimit(int productID)
        {
            using (var session = SessionManager.Session)
            {
                return session.Get<Product>(productID).ProductGroup.DiscountLimit;
            }
        }
        static public bool IsBillPrinted(int voucherID)
        {
            using (var session = SessionManager.Session)
            {
                return session.Get<Voucher>(voucherID).Printed;
            }
        }
        static public int? Insert(Voucher voucher)
        {
            using (var session = SessionManager.Session)
            {
                using (var trans = session.BeginTransaction())
                {
                    var dt = DbValues.Date;
                    voucher.CreationDate = dt;
                    voucher.LastEditDate = dt;
                    voucher.Date = dt;
                    voucher.KotID = DbValues.KotID;
                    voucher.BillID = voucher.Printed ? DbValues.BillID : 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;
                    }
                    UpdateSettlements(voucher, session);
                    session.Save(voucher);
                    using (var ft = new FoodTableBI(session, true))
                        ft.UpdateStatus(voucher);
                    trans.Commit();
                    return addedKot == null ? (int?)null : addedKot.KotID;
                }
            }
        }

        private static void UpdateSettlements(Voucher voucher, ISession session)
        {
            var amount = -1 * voucher.Kots.Sum(x => x.Inventories.Sum(y => y.Amount));
            amount = Math.Round(amount, 5);
            if (voucher.Settlements.Count(x => x.Settled == SettleOption.Amount) == 0)
                voucher.Settlements.Add(new VoucherSettlement() { Amount = amount, Settled = SettleOption.Amount });
            else
                voucher.Settlements.Single(x => x.Settled == SettleOption.Amount).Amount = amount;

            var roundoff = Math.Round(amount) - amount;
            if (voucher.Settlements.Count(x => x.Settled == SettleOption.RoundOff) == 0)
                voucher.Settlements.Add(new VoucherSettlement() { Amount = roundoff, Settled = SettleOption.RoundOff });
            else
                voucher.Settlements.Single(x => x.Settled == SettleOption.RoundOff).Amount = roundoff;

            var balance = voucher.Settlements.Where(x => x.Settled != SettleOption.Unsettled).Sum(x => x.Amount) * -1;
            if (voucher.Settlements.Count(x => x.Settled == SettleOption.Unsettled) == 0)
                voucher.Settlements.Add(new VoucherSettlement() { Amount = balance, Settled = SettleOption.Unsettled });
            else if (balance == 0)
                voucher.Settlements.Remove(voucher.Settlements.Single(x => x.Settled == SettleOption.Unsettled));
            else
                voucher.Settlements.Single(x => x.Settled == SettleOption.Unsettled).Amount = balance;
        }

        public static void Delete(int voucherID)
        {
            using (var session = SessionManager.Session)
            {
                using (var trans = session.BeginTransaction())
                {
                    session.Delete(session.Get<Voucher>(voucherID));
                    using (var ft = new FoodTableBI(session, true))
                    {
                        var table = session.QueryOver<FoodTable>()
                                    .Where(x => x.VoucherID == voucherID)
                                    .SingleOrDefault();
                        ft.UpdateStatus(table.Name, voucherID, null);
                    }
                    trans.Commit();
                }
            }
        }

        static public int? Update(Voucher voucher)
        {
            using (var session = SessionManager.Session)
            {
                using (var trans = session.BeginTransaction())
                {
                    var dt = DbValues.Date;
                    voucher.LastEditDate = dt;
                    if (voucher.Date == null)
                    {
                        voucher.Date = dt;
                        voucher.BillID = DbValues.BillID;
                    }
                    if (!voucher.Printed)
                        voucher.Date = dt;
                    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;
                    }
                    UpdateSettlements(voucher, session);
                    session.Update(voucher);
                    using (var ft = new FoodTableBI(session, true))
                        ft.UpdateStatus(voucher);
                    trans.Commit();
                    if (addedKot == null)
                        return null;
                    else
                        return addedKot.KotID;
                }
            }
        }
        //static private void UpdateTable(Voucher voucher, ISession session)
        //{
        //    using (var ft = new FoodTableBI(session, true))
        //    {
        //        string status;
        //        if (!voucher.Printed)
        //            status = "running";
        //        else if (voucher.Settlements.Count(x => x.Settled == SettleOption.Unsettled) != 0 && voucher.Void == false)
        //            status = "printed";
        //        else
        //            status = null;
        //        ft.UpdateStatus(voucher.TableID, voucher.VoucherID, status);
        //    }
        //}
        static public Voucher Get(int voucherID)
        {
            using (var session = SessionManager.Session)
            {
                var voucher = session.Get<Voucher>(voucherID);
                NHibernateUtil.Initialize(voucher.Customer);
                NHibernateUtil.Initialize(voucher.Waiter);
                NHibernateUtil.Initialize(voucher.User);
                foreach (var kot in voucher.Kots)
                {
                    NHibernateUtil.Initialize(kot);
                    foreach (var item in kot.Inventories)
                    {
                        NHibernateUtil.Initialize(item);
                        NHibernateUtil.Initialize(item.Product);
                        foreach (var inmod in item.InventoryModifier)
                            NHibernateUtil.Initialize(inmod.Modifier);
                    }
                }
                foreach (var item in voucher.Settlements)
                    NHibernateUtil.Initialize(item);
                return voucher;
            }
        }

        static public void VoidBill(int voucherID, string reason)
        {
            using (var session = SessionManager.Session)
            {
                using (var trans = session.BeginTransaction())
                {
                    var voucher = session.Get<Voucher>(voucherID);
                    voucher.Void = true;
                    voucher.VoidReason = reason;
                    session.Save(voucher);
                    using (var ft = new FoodTableBI(session, true))
                        ft.UpdateStatus(voucher);
                    trans.Commit();
                }
            }
        }

        static public void SettleVoucher(User user, int voucherID, IDictionary<SettleOption, decimal> values)
        {
            using (var session = SessionManager.Session)
            {
                using (var trans = session.BeginTransaction())
                {
                    var voucher = session.Get<Voucher>(voucherID);
                    foreach (var item in voucher.Settlements.Where(x => x.Settled != SettleOption.Amount && x.Settled != SettleOption.RoundOff && x.Settled != SettleOption.Unsettled))
                        session.Delete(item);
                    foreach (var item in values.Where(x => x.Key != SettleOption.Amount && x.Key != SettleOption.RoundOff && x.Key != SettleOption.Unsettled))
                        voucher.Settlements.Add(new VoucherSettlement { Settled = item.Key, Amount = item.Value });
                    UpdateSettlements(voucher, session);
                    voucher.User = user;
                    voucher.LastEditDate = DbValues.Date;
                    session.Update(voucher);
                    using (var ft = new FoodTableBI(session, true))
                        ft.UpdateStatus(voucher);
                    trans.Commit();
                }
            }
        }
        public static int MoveKot(int kotID, FoodTable foodTable)
        {
            var session = SessionManager.Session;
            using (var trans = session.BeginTransaction())
            {
                var kot = session.Get<Kot>(kotID);
                foodTable = session.Get<FoodTable>(foodTable.FoodTableID);
                var voucher = session.Get<Voucher>(foodTable.VoucherID);
                voucher.Kots.Add(kot);
                session.Update(voucher);
                trans.Commit();
                return voucher.VoucherID;
            }
        }

    }
}