feature exchange rate update automation

Automated downloading exchange rates from HMRC and updating the database. Added function call to the console and form applications.

Also added a form to show the console output in form application.

src/bnhtrade.Core/Logic/Account/Currency.cs

@@ -1,23 +1,200 @@
-using System;
+using FikaAmazonAPI.ConstructFeed.Messages;
+using System;
 using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Data.SqlClient;
+using System.Globalization;
 using System.Linq;
 using System.Text;
+using System.Threading;
 using System.Threading.Tasks;
+using System.Xml.Linq;
 
 namespace bnhtrade.Core.Logic.Account
 {
     public  class Currency
     {
+        Log.LogEvent log = new Log.LogEvent();
+
         public decimal CurrencyConvertToGbp(string currencyCode, decimal amount, DateTime conversionDate)
         {
-            return new Data.Database.Account.Currency().CurrencyConvertToGbp(currencyCode, amount, conversionDate);
+            if (currencyCode == "GBP" || amount == 0M)
+            {
+                return amount;
+            }
+
+            if (currencyCode.Length != 3)
+            {
+                throw new Exception("Invalid currency code '" + currencyCode + "'");
+            }
+
+            var db = new Data.Database.Account.Currency();
+            var exchageRate = db.ReadExchangeRate(currencyCode, conversionDate);
+
+            if (exchageRate != null)
+            {
+                return amount / Convert.ToDecimal(exchageRate);
+            }
+            else
+            {
+                throw new Exception("Currency code '" + currencyCode + "' or date " + conversionDate.ToShortDateString() + " " + conversionDate.ToLongTimeString() + "' does not exist in the Exchange Rate table");
+            }
+
         }
 
-        public int CurrencyExchangeRateInsert(int exchangeRateSource, string currencyCode,
-            decimal currencyUnitsPerGbp, DateTime periodStart, DateTime periodEnd, bool checkOverride = false)
+        private DateTime GetHmrcMaxPeriodAvaible()
         {
-            return new Data.Database.Account.Currency().CurrencyExchangeRateInsert(exchangeRateSource, currencyCode,
-                currencyUnitsPerGbp, periodStart, periodEnd, checkOverride);
+            // HMRC monthly sxchange rates are published on the penultimate Thursday of the month before
+            // For some leeway we'll use the penultimate Friday
+
+            // find penultimate Friday for current month
+            var ukTimeNow = new Logic.Utilities.DateTime().ConvertUtcToUk(DateTime.UtcNow);
+            var monthDayCount = DateTime.DaysInMonth(ukTimeNow.Year, ukTimeNow.Month);
+            var thisMonthPenultimateFriday = DateTime.SpecifyKind(new DateTime(ukTimeNow.Year, ukTimeNow.Month, monthDayCount), DateTimeKind.Unspecified);
+            int count = 0;
+            int fridayCount = 0;
+            while (count != 15)
+            {
+                if (thisMonthPenultimateFriday.DayOfWeek == DayOfWeek.Friday)
+                {
+                    fridayCount++;
+                    if (fridayCount == 2)
+                    {
+                        break;
+                    }
+                }
+                thisMonthPenultimateFriday = thisMonthPenultimateFriday.AddDays(-1);
+                count++;
+            }
+
+            if (count == 15)
+            {
+                throw new Exception("Something went wrong here ErrorID:ef7f5d8f-0f7b-4014-aa65-421ecd5d7367");
+            }
+
+            var mostRecentPeriodAvaible = DateTime.SpecifyKind(new DateTime(ukTimeNow.Year, ukTimeNow.Month, 1), DateTimeKind.Unspecified); ;
+            if (ukTimeNow >= thisMonthPenultimateFriday)
+            {
+                mostRecentPeriodAvaible = mostRecentPeriodAvaible.AddMonths(1);
+            }
+
+            return mostRecentPeriodAvaible;
+        }
+
+        public void UpdateHmrcExchageRates()
+        {
+            log.LogInformation("Starting update database HMRC exchange rates");
+
+            int exchangeRateSourceId = 1; // id for hmrc
+
+            // retrive most recent data from db
+            var db = new Data.Database.Account.Currency();
+            var dbLatestRates = db.ReadExchangeRateLatest();
+
+            // sanity check, make sure there are no duplicates
+            int count = 0;
+            foreach (var exchageRate in dbLatestRates)
+            {
+                count = 0;
+                var currency = exchageRate.CurrencyCode;
+                foreach (var subExchageRate in dbLatestRates)
+                {
+                    if (exchageRate.CurrencyCode == subExchageRate.CurrencyCode)
+                    {
+                        count = 1;
+                    }
+                }
+                if (count > 1)
+                {
+                    throw new FormatException("Datebase returned duplicate information");
+                }
+            }
+
+            // test for no data (first time running)
+            var hmrcMonthToRetrive = new DateTime();
+            if (dbLatestRates.Any() == false)
+            {
+                hmrcMonthToRetrive = Data.Database.Constants.GetBusinessStartUk();
+            }
+
+            // set first/earliest month to retrive from hmrc website
+            foreach (var exchageRate in dbLatestRates)
+            {
+                var dbEndDateTime = exchageRate.DateTimeEndUk;
+
+                if (hmrcMonthToRetrive == default(DateTime))
+                {
+                    hmrcMonthToRetrive = dbEndDateTime;
+                }
+                else
+                {
+                    if (dbEndDateTime < hmrcMonthToRetrive)
+                    {
+                        hmrcMonthToRetrive = dbEndDateTime;
+                    }
+                }
+            }
+
+            // check - more coding required to retrive periods before 2021-01-01
+            if (hmrcMonthToRetrive < DateTime.SpecifyKind(new DateTime(2021, 1, 1), DateTimeKind.Unspecified))
+            {
+                throw new Exception("This function does not currently retirve exchange rates from HMRC for dates before 2021-01-01");
+            }
+
+            // check if retrival from hmrc is required
+            var hmrcMaxMonthAvaible = GetHmrcMaxPeriodAvaible();
+            if (hmrcMonthToRetrive.Year == hmrcMaxMonthAvaible.Year && hmrcMonthToRetrive.Month > hmrcMaxMonthAvaible.Month)
+            {
+                // nothing to retrive
+                log.LogInformation("Exchange rates curretly up to date, exiting.");
+                return;
+            }
+
+            // get info from hmrc and insert data in db
+            while (hmrcMonthToRetrive <= hmrcMaxMonthAvaible)
+            {
+                count = 0;
+
+                var url = new string(
+                    "https://www.trade-tariff.service.gov.uk/api/v2/exchange_rates/files/monthly_xml_"
+                    + hmrcMonthToRetrive.Year.ToString()
+                    + "-"
+                    + hmrcMonthToRetrive.Month.ToString()
+                    + ".xml"
+                    );
+                var xd = new XDocument();
+                xd = XDocument.Load(url);
+
+                foreach (var exchageRate in dbLatestRates)
+                {
+                    if (exchageRate.DateTimeStartUtc < hmrcMonthToRetrive)
+                    {
+                        //retrive exchange rate from xml
+                        XElement node = xd.Root.Elements("exchangeRate").Where(e => e.Element("currencyCode").Value == exchageRate.CurrencyCode.ToString()).FirstOrDefault();
+                        decimal rate = decimal.Parse(node.Element("rateNew").Value);
+                        rate = decimal.Round(rate, 4);
+
+                        // insert into db
+                        new Data.Database.Account.Currency().InsertExchangeRate(
+                            exchangeRateSourceId
+                            , exchageRate.CurrencyCode
+                            , rate
+                            , new Utilities.DateTime().ConvertUkToUtc(hmrcMonthToRetrive)
+                            , new Utilities.DateTime().ConvertUkToUtc(hmrcMonthToRetrive.AddMonths(1))
+                            );
+
+                        count++;
+                    }
+                }
+
+                log.LogInformation(
+                    count + " new exchange rate(s) added to database for " + hmrcMonthToRetrive.ToString("MMMM") + " " + hmrcMonthToRetrive.Year.ToString()
+                    );
+
+                hmrcMonthToRetrive = hmrcMonthToRetrive.AddMonths(1);
+            }
+
+            log.LogInformation("Updating database currency exchange rates complete.");
         }
     }
 }

src/bnhtrade.Core/Logic/Utilities/DateTime.cs

@@ -0,0 +1,51 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace bnhtrade.Core.Logic.Utilities
+{
+    public class DateTime
+    {
+        public System.DateTime ConvertUkToUtc(System.DateTime ukDateTime)
+        {
+            if (ukDateTime.Kind == DateTimeKind.Local && TimeZoneInfo.Local.Id != "GMT Standard Time")
+            {
+                throw new System.ArgumentException("DateTime kind set to local, local is not set to 'GMT Standard Time'");
+            }
+            else if (ukDateTime.Kind == DateTimeKind.Utc)
+            {
+                throw new System.ArgumentException("DateTime kind is UTC");
+            }
+
+            TimeZoneInfo ukZone = TimeZoneInfo.FindSystemTimeZoneById("GMT Standard Time");
+            System.DateTime ukTime = TimeZoneInfo.ConvertTimeToUtc(ukDateTime, ukZone);
+            return ukTime; // is returned as DateTimeKind 'unspecified'
+        }
+
+        public System.DateTime ConvertUtcToUk(System.DateTime utcDateTime)
+        {
+            if (utcDateTime.Kind != DateTimeKind.Utc)
+            {
+                throw new System.ArgumentException("DateTime kind is not UTC");
+            }
+
+            TimeZoneInfo ukZone = TimeZoneInfo.FindSystemTimeZoneById("GMT Standard Time");
+            System.DateTime ukTime = TimeZoneInfo.ConvertTimeFromUtc(utcDateTime, ukZone);
+            return ukTime; // is returned as DateTimeKind 'unspecified'
+        }
+
+        public System.DateTime ParseIsoDateTimeString(string reportDateTime)
+        {
+            string isoDateTime =
+                reportDateTime.Substring(6, 4) + "-" +
+                reportDateTime.Substring(3, 2) + "-" +
+                reportDateTime.Substring(0, 2) + "T" +
+                reportDateTime.Substring(11, 2) + ":" +
+                reportDateTime.Substring(14, 2) + ":" +
+                reportDateTime.Substring(17, 2) + "Z";
+            return System.DateTime.Parse(isoDateTime);
+        }
+    }
+}

src/bnhtrade.Core/Logic/Utilities/DateTimeCheck.cs

@@ -8,9 +8,9 @@ namespace bnhtrade.Core.Logic.Utilities
 {
     public class DateTimeCheck : Validate.Validate
     {
-        public bool IsUtc(DateTime dateTimeToCheck)
+        public bool IsUtc(System.DateTime dateTimeToCheck)
         {
-            if (dateTimeToCheck == default(DateTime))
+            if (dateTimeToCheck == default(System.DateTime))
             {
                 ValidationResultAdd( "DateTime value set to default.");
                 return false;
@@ -22,9 +22,9 @@ namespace bnhtrade.Core.Logic.Utilities
             }
             return true;
         }
-        public bool IsLocal(DateTime dateTimeToCheck)
+        public bool IsLocal(System.DateTime dateTimeToCheck)
         {
-            if (dateTimeToCheck == default(DateTime))
+            if (dateTimeToCheck == default(System.DateTime))
             {
                 ValidationResultAdd("DateTime value set to default.");
                 return false;

src/bnhtrade.Core/Logic/Utilities/DateTimeParse.cs

@@ -1,23 +0,0 @@
-using System;
-using System.Collections.Generic;
-using System.Linq;
-using System.Text;
-using System.Threading.Tasks;
-
-namespace bnhtrade.Core.Logic.Utilities
-{
-    public class DateTimeParse
-    {
-        public DateTime ParseMwsReportDateTime(string reportDateTime)
-        {
-            string isoDateTime =
-                reportDateTime.Substring(6, 4) + "-" +
-                reportDateTime.Substring(3, 2) + "-" +
-                reportDateTime.Substring(0, 2) + "T" +
-                reportDateTime.Substring(11, 2) + ":" +
-                reportDateTime.Substring(14, 2) + ":" +
-                reportDateTime.Substring(17, 2) + "Z";
-            return DateTime.Parse(isoDateTime);
-        }
-    }
-}

src/bnhtrade.Core/Logic/Utilities/ListFunction.cs

@@ -0,0 +1,59 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace bnhtrade.Core.Logic.Utilities
+{
+    public class ListFunction
+    {
+        public ListFunction() { }
+
+        /// <summary>
+        /// Outputs a unique list from an input list
+        /// </summary>
+        /// <param name="inputList"></param>
+        /// <param name="includeWhiteSpace"></param>
+        /// <returns>Unique list</returns>
+        public List<string> UniqueList(List<string> inputList, bool removeNullorWhitespace = true)
+        {
+            List<string> outputList = new List<string>();
+
+            foreach (string input in inputList)
+            {
+                if (string.IsNullOrWhiteSpace(input) && removeNullorWhitespace)
+                {
+                    break;
+                }
+
+                bool stringExists = false;
+                foreach (string output in outputList)
+                {
+                    if (output == input)
+                    {
+                        stringExists = true;
+                        break;
+                    }
+                }
+
+                if (stringExists == false)
+                {
+                    outputList.Add(input);
+                }
+            }
+
+            return outputList;
+        }
+
+        public List<string> UniqueList(List<Enum> inputList, bool removeNullorWhitespace = true)
+        {
+            List<string> stringList = new List<string>();
+            foreach (Enum input in inputList)
+            {
+                stringList.Add(input.ToString());
+            }
+            return UniqueList(stringList, removeNullorWhitespace);
+        }
+    }
+}

src/bnhtrade.Core/Logic/Utilities/NightlyRoutine.cs

@@ -21,6 +21,7 @@ namespace bnhtrade.Core.Logic.Utilities
             var export = new bnhtrade.Core.Logic.Export.AmazonSettlement();
 
             bool stockUpdate = false;
+            bool exchangeRate = false;
             bool accountProcess = false;
 
             while (true)
@@ -28,6 +29,7 @@ namespace bnhtrade.Core.Logic.Utilities
                 try
                 {
                     if (stockUpdate == false) { stockUpdate = true; new bnhtrade.Core.Logic.Import.Amazon().SyncAllWithDatabase(); ; }
+                    if (exchangeRate == false) { exchangeRate = true; new Logic.Account.Currency().UpdateHmrcExchageRates(); }
                     if (accountProcess == false) { accountProcess = true; export.ToInvoice(); }
 
                     // if (stockProcess == false) { stockProcess = true; stock.ProcessFbaStockImportData(); }