using System;
using System.Collections.Generic;
using Microsoft.Data.SqlClient;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Transactions;

namespace bnhtrade.Core.Data.Database.Stock
{
    public class UpdateSkuTransaction : Connection
    {
        // Any update method below to the quanity, isprocessed or journalId, implements a consistancy check.

        private string err = "Database UpdateSkuTransaction: ";
        private ReadSkuTransaction dbRead = new ReadSkuTransaction();

        public UpdateSkuTransaction()
        {
        }

        public void Update(Model.Stock.SkuTransaction skuTransaction)
        {
            // Consistancy check: is the target marked as is processed?
            dbRead.Init();
            if (dbRead.GetIsProcessed(skuTransaction.SkuTransactionId))
                throw new InvalidOperationException("Update restricted, sku transaction isProcessed=true");

            using (var conn = new SqlConnection(SqlConnectionString))
            {
                conn.Open();

                using (SqlCommand cmd = new SqlCommand(@"
                    UPDATE tblStockSkuTransaction
                    SET TransactionDate = @transactionDate
	                    ,StockSkuTransactionTypeID = (
		                    SELECT StockSkuTransactionTypeID
		                    FROM tblStockSkuTransactionType
		                    WHERE TypeCode = @skuTransactionTypeCode
		                    )
	                    ,ForeignKey = @foreignKey
	                    ,Reference = @reference
	                    ,Detail = @Detail
	                    ,SkuID = (
		                    SELECT skuSkuID
		                    FROM tblSku
		                    WHERE skuSkuNumber = @skuNumber
		                    )
	                    ,Quantity = @quantity
	                    ,IsProcessed = @isProcessed
	                    ,StockJournalID = @stockJournalID
                    WHERE StockSkuTransactionID = @transactionId
                    ", conn))
                {
                    cmd.Parameters.AddWithValue("@transactionDate", skuTransaction.TransactionDate.ToUniversalTime());
                    cmd.Parameters.AddWithValue("@skuTransactionTypeCode", skuTransaction.SkuTransactionTypeCode);
                    if (skuTransaction.ForeignKey == null) { cmd.Parameters.AddWithValue("@foreignKey", DBNull.Value); }
                    else { cmd.Parameters.AddWithValue("@foreignKey", skuTransaction.ForeignKey); }
                    if (skuTransaction.Reference == null) { cmd.Parameters.AddWithValue("@reference", DBNull.Value); }
                    else { cmd.Parameters.AddWithValue("@reference", skuTransaction.Reference); }
                    if (skuTransaction.Detail == null) { cmd.Parameters.AddWithValue("@detail", DBNull.Value); }
                    else { cmd.Parameters.AddWithValue("@detail", skuTransaction.Detail); }
                    cmd.Parameters.AddWithValue("@skuNumber", skuTransaction.SkuNumber);
                    cmd.Parameters.AddWithValue("@quantity", skuTransaction.Quantity);
                    cmd.Parameters.AddWithValue("@isProcessed", skuTransaction.IsProcessed);
                    if (skuTransaction.StockJournalId == null) { cmd.Parameters.AddWithValue("@stockJournalID", DBNull.Value); }
                    else { cmd.Parameters.AddWithValue("@stockJournalID", skuTransaction.StockJournalId); }
                    cmd.Parameters.AddWithValue("@transactionId", skuTransaction.SkuTransactionId);

                    int effected = cmd.ExecuteNonQuery();

                    if (effected < 1)
                    {
                        throw new Exception(err += "stockSkuTransaction IsProcessed update failed");
                    }
                }
            }
        }

        /// <summary>
        /// Update the isProcessed and StockJournalId field, with journal consistancy check.
        /// </summary>
        /// <param name="skuTransactionId">Sku Transaction Id</param>
        /// <param name="isProcessed"></param>
        /// <param name="stockJournalId"></param>
        /// <exception cref="InvalidOperationException">Invalid journalId, isProcessed combination</exception>
        /// <exception cref="Exception">DB update sql fail</exception>
        public void UpdateIsProcessed(int skuTransactionId, bool isProcessed, int? stockJournalId, bool enableJournalDelete = false)
        {
            // IMPORTANT!!!!
            // For consistancy reasons: need to make sure that if a journal entry exists, it is deteled before it is
            // edited, or removed from the transaction table
            // Best to implement this here, at only point where the isprocessed/journalId can be updated


            // intial checks
            if (isProcessed == false && stockJournalId != null)
                throw new InvalidOperationException("If stock journal id is set, isProcessed must be true");


            using (var scope = new TransactionScope())
            {
                try
                {
                    // check for existing journal Id in transactin table
                    var existingJournalId = new Data.Database.Stock.ReadSkuTransaction().GetJournalId(skuTransactionId);
                    bool journalDeleteRequired = false;
                    if (existingJournalId != null)
                    {
                        if (stockJournalId == null || stockJournalId != existingJournalId)
                        {
                            journalDeleteRequired = true;
                        }
                    }

                    // make the journal delete, if required and enabled
                    if (journalDeleteRequired && enableJournalDelete)
                    {
                        new Data.Database.Stock.JournalCrud().StockJournalDelete((int)existingJournalId);
                    }
                    else
                    {
                        throw new InvalidOperationException("Removal of stock journal to update sku transaction table not allowed");
                    }

                    // update the transaction table
                    string sql = @"
                    UPDATE tblStockSkuTransaction
                    SET IsProcessed = @isProcessed
	                    ,StockJournalID = @stockJournalID 
                    WHERE StockSkuTransactionID = @transactionId;";

                    using (var conn = new SqlConnection(SqlConnectionString))
                    {
                        conn.Open();

                        using (SqlCommand cmd = new SqlCommand(sql, conn))
                        {
                            cmd.Parameters.AddWithValue("@isProcessed", isProcessed);
                            if (stockJournalId == null) { cmd.Parameters.AddWithValue("@stockJournalID", DBNull.Value); }
                            else { cmd.Parameters.AddWithValue("@stockJournalID", (int)stockJournalId); }
                            cmd.Parameters.AddWithValue("@transactionId", skuTransactionId);

                            int effected = cmd.ExecuteNonQuery();

                            if (effected != 1)
                            {
                                throw new Exception(err += "Sku Transaction StockJournalID update failed");
                            }
                        }
                    }
                    scope.Complete();
                }
                catch (Exception ex)
                {
                    scope.Dispose();
                    throw ex;
                }
            }
        }

        /// <summary>
        /// Update the quantity field, with journal consistancy check.
        /// </summary>
        /// <param name="skuTransactionId">stock sku transaction id</param>
        /// <param name="quantity">quantity</param>
        /// <exception cref="InvalidOperationException">Update restricted, sku transaction isProcessed=true</exception>
        /// <exception cref="Exception">Database write failed</exception>
        public void UpdateQuanitity(int skuTransactionId, int quantity)
        {
            // Consistancy check: is the target marked as is processed?
            dbRead.Init();
            if (dbRead.GetIsProcessed(skuTransactionId))
                throw new InvalidOperationException("Update restricted, sku transaction isProcessed=true");

            using (var conn = new SqlConnection(SqlConnectionString))
            {
                conn.Open();

                using (SqlCommand cmd = new SqlCommand(@"
                    UPDATE tblStockSkuTransaction
                    SET Quantity = @quantity
                    WHERE StockSkuTransactionID = @transactionId
                    ", conn))
                {
                    cmd.Parameters.AddWithValue("@quantity", quantity);

                    int effected = cmd.ExecuteNonQuery();

                    if (effected != 1)
                    {
                        throw new Exception(err += "stockSkuTransaction Quantity update failed");
                    }
                }
            }
        }
    }
}