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

namespace Tanshu.Accounts.Repository
{
    public partial class VoucherBI : UnitOfWork<Voucher>
    {
        public new Guid Insert(Voucher voucher)
        {
            _session.Save(voucher);
            Kot addedKot = null;
            foreach (var item in voucher.Kots.Where(item => item.KotID == Guid.Empty))
            {
                addedKot = item;
                item.Voucher = voucher;
                item.Printed = true;
                item.Table = voucher.Table;
                item.User = voucher.User;
                UpdateBillType(voucher);
                _session.Save(item);
                int index = 0;
                foreach (var inv in item.Inventories)
                {
                    inv.Kot = item;
                    inv.SortOrder = index;
                    index++;
                    _session.Save(inv);
                    foreach (var modifier in inv.InventoryModifier)
                    {
                        modifier.Inventory = inv;
                        _session.Save(modifier);
                    }
                }
            }
            var options = GetSettlementOptions(voucher);
            UpdateSettlements(voucher, options);
            return addedKot == null ? Guid.Empty : addedKot.KotID;
        }
        public new Guid? Update(Voucher voucher)
        {
            _session.Update(voucher);

            Kot addedKot = null;
            foreach (var item in voucher.Kots.Where(item => item.KotID == Guid.Empty))
            {
                addedKot = item;
                item.Voucher = voucher;
                item.Printed = true;
                item.Table = voucher.Table;
                item.User = voucher.User;
                _session.Save(item);
                int index = 0;
                foreach (var inv in item.Inventories)
                {
                    inv.Kot = item;
                    inv.SortOrder = index;
                    index++;
                    _session.Save(inv);
                    foreach (var modifier in inv.InventoryModifier)
                    {
                        modifier.Inventory = inv;
                        _session.Save(modifier);
                    }
                }
            }
            UpdateBillType(voucher);
            var options = GetSettlementOptions(voucher);
            UpdateSettlements(voucher, options);
            return addedKot == null ? (Guid?)null : addedKot.KotID;
        }
        public new Voucher Get(Expression<Func<Voucher, bool>> query)
        {
            var voucher = _session.QueryOver<Voucher>()
                .Where(query)
                .SingleOrDefault();
            if (voucher == null)
                return voucher;
            NHibernateUtil.Initialize(voucher.Customer);
            NHibernateUtil.Initialize(voucher.User);
            NHibernateUtil.Initialize(voucher.Table);
            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);
                    NHibernateUtil.Initialize(item.Vat);
                    NHibernateUtil.Initialize(item.ServiceTax);
                }
            }
            foreach (var item in voucher.Settlements)
                NHibernateUtil.Initialize(item);
            return voucher;
        }
        public void VoidBill(Guid voucherID, string reason)
        {
            var voucher = _session.Get<Voucher>(voucherID);
            voucher.Void = true;
            voucher.VoidReason = reason;
            _session.Update(voucher);
        }

        public void UpdateTable(Expression<Func<FoodTable, bool>> query, Guid? newVoucherID, string status)
        {
            var table = _session.QueryOver<FoodTable>().Where(query).SingleOrDefault();
            if (table == null)
                throw new ValidationException("Old Voucher on the table does not match");
            table.Status = status;
            table.VoucherID = newVoucherID;
            _session.Update(table);
        }

        public Guid MergeKot(Guid kotID, string tableName)
        {
            var kot = _session.Get<Kot>(kotID);
            var oldVoucher = kot.Voucher;
            var table = _session.QueryOver<FoodTable>().Where(x => x.Name == tableName).SingleOrDefault();
            var newVoucher = _session.Get<Voucher>(table.VoucherID);

            oldVoucher.Kots.Remove(kot);
            kot.Voucher = newVoucher;
            newVoucher.Kots.Add(kot);

            _session.Update(kot);
            _session.Update(oldVoucher);
            _session.Update(newVoucher);
            return newVoucher.VoucherID;
        }

        public Guid MergeTables(Guid voucherID, string tableName)
        {
            var newTable = _session.QueryOver<FoodTable>().Where(x => x.Name == tableName).SingleOrDefault();
            var newVoucher = _session.Get<Voucher>(newTable.VoucherID);
            var oldVoucher = _session.Get<Voucher>(voucherID);
            for (var i = oldVoucher.Kots.Count - 1; i >= 0; i--)
            {
                var kot = oldVoucher.Kots[i];
                oldVoucher.Kots.Remove(kot);
                kot.Voucher = newVoucher;
                newVoucher.Kots.Add(kot);
                _session.Update(kot);
            }
            _session.Update(newVoucher);


            foreach (var item in oldVoucher.Settlements)
            {
                _session.Delete(item);
            }
            _session.Delete(oldVoucher);
            return newVoucher.VoucherID;
        }
        private void UpdateBillType(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.ServiceTaxRate = 0;
                        item.VatRate = 0;
                        if (item.InventoryID != Guid.Empty)
                            _session.Update(item);
                    }
                    break;
                case VoucherType.TakeAway:
                    foreach (var item in voucher.Kots.SelectMany(kot => kot.Inventories))
                    {
                        item.ServiceCharge = 0;
                        item.ServiceTaxRate = 0;
                        if (item.InventoryID != Guid.Empty)
                            _session.Update(item);
                    }
                    break;
                case VoucherType.Staff:
                    foreach (var item in voucher.Kots.SelectMany(kot => kot.Inventories))
                    {
                        item.ServiceCharge = 0;
                        item.ServiceTaxRate = 0;
                        item.VatRate = 0;
                        if (item.InventoryID != Guid.Empty)
                            _session.Update(item);
                    }
                    break;
            }
        }

        public Guid MoveKot(Guid kotID, Guid tableID)
        {
            var kot = _session.Get<Kot>(kotID);
            var oldVoucher = _session.Get<Voucher>(kot.Voucher.VoucherID);
            var table = _session.QueryOver<FoodTable>().Where(x => x.FoodTableID == tableID).SingleOrDefault();
            var newVoucher = new Voucher(Session.User, oldVoucher.Customer, table, false, false, "");
            Insert(newVoucher);

            oldVoucher.Kots.Remove(kot);
            kot.Voucher = newVoucher;
            newVoucher.Kots.Add(kot);

            _session.Update(kot);
            _session.Update(oldVoucher);
            _session.Update(newVoucher);

            return newVoucher.VoucherID;
        }

        public void SplitBill(Guid oldVoucherID, Voucher first, Voucher second)
        {
            var oldVoucher = _session.Get<Voucher>(oldVoucherID);
            oldVoucher.User = Session.User;
            oldVoucher.Void = true;
            oldVoucher.VoidReason = "Bill Split";

            Insert(first);
            Insert(second);
            Update(oldVoucher);
        }

        public void DiscountPrintedBill(Guid oldVoucherID, Voucher newVoucher)
        {
            Insert(newVoucher);

            var oldVoucher = _session.Get<Voucher>(oldVoucherID);
            oldVoucher.User = Session.User;
            oldVoucher.Void = true;
            oldVoucher.VoidReason = string.Format("Bill Discounted / Changed. New Bill ID is {0}", newVoucher.FullBillID);
            Update(oldVoucher);
        }
        public void MoveTable(Guid voucherID, Guid tableID)
        {
            var voucher = _session.Get<Voucher>(voucherID);
            var newTable = _session.QueryOver<FoodTable>().Where(x => x.FoodTableID == tableID).SingleOrDefault();
            voucher.Table = newTable;
            _session.Update(voucher);
        }
    }
}