private void InitializeApp()
{
CultureInfo.DefaultThreadCurrentCulture = new CultureInfo("pl-PL");
NbpClient = new NbpClient();
InitializeDatabase();
MainPage = new TabsPage();
}
public async Task <GetExchangeRateModel> Handle(GetExchangeRateQuery request, CancellationToken cancellationToken)
{
var datesBetweenStartAndEndDateDividedByDay = GetDatesBetweenStartAndEndDateDividedByDay();
await FillGapsInMissingDailyExchangeRates(datesBetweenStartAndEndDateDividedByDay);
var model = await CreateExchangeRateModel(datesBetweenStartAndEndDateDividedByDay);
return(model);
#region Inner methods
List <DateTime> GetDatesBetweenStartAndEndDateDividedByDay()
{
var startDateAfterFormat = DateTime.Parse(request.StartDate);
var endDateAfterFormat = DateTime.Parse(request.EndDate);
var datesBetweenStartAndEndDateDividedByDay = new List <DateTime> {
startDateAfterFormat
};
while (endDateAfterFormat > datesBetweenStartAndEndDateDividedByDay.Last().AddDays(1))
{
var dateDayLater = datesBetweenStartAndEndDateDividedByDay.Last().AddDays(1);
datesBetweenStartAndEndDateDividedByDay.Add(dateDayLater);
}
datesBetweenStartAndEndDateDividedByDay.Add(endDateAfterFormat);
return(datesBetweenStartAndEndDateDividedByDay);
}
async Task FillGapsInMissingDailyExchangeRates(List <DateTime> datesBetween)
{
var gapDays = await GetGapDays(datesBetween);
var getNbpExchangeRateDailyQueries = ConvertGapPeriodsToNbpExchangeRateQueries(gapDays);
var nbpExchangeRateModel = await NbpClient.GetNbpExchangeRateModels(getNbpExchangeRateDailyQueries, cancellationToken);
await SaveNbpExchangeRateModels(nbpExchangeRateModel);
}
async Task <List <DateTime> > GetGapDays(List <DateTime> datesBetween)
{
var gapDaysCollection = new List <DateTime>();
for (int i = 0; i < datesBetween.Count; i++)
{
if (!await databaseContext.DailyExchangeRate
.AnyAsync(rate => rate.Date.Equals(datesBetween[i]), cancellationToken))
{
gapDaysCollection.Add(datesBetween[i]);
}
}
return(gapDaysCollection);
}
async Task <GetExchangeRateModel> CreateExchangeRateModel(List <DateTime> datesBetween)
{
var dailyExchangeRatesDto = await GetDailyExchangeRatesDto(datesBetween);
var isoCurrencyCode = request.CurrencyIsoCode.ToUpper();
var exchangeRates = dailyExchangeRatesDto.Select(rate => rate.ExchangeRate);
var averageRatesForProvidedPeriod = exchangeRates.Sum() / exchangeRates.Count();
var dailyExchangeRates = dailyExchangeRatesDto
.Select(dto => new GetExchangeRateDailyModel(dto.Date, dto.ExchangeRate))
.ToList();
var getExchangeRateModel = new GetExchangeRateModel(dailyExchangeRates, averageRatesForProvidedPeriod, isoCurrencyCode);
return(getExchangeRateModel);
}
async Task <List <DailyExchangeRateDto> > GetDailyExchangeRatesDto(List <DateTime> datesBetween)
{
return(await databaseContext
.DailyExchangeRate
.Where(exchangeRate =>
datesBetween.Any(dateBetween => dateBetween == exchangeRate.Date))
.Select(exchangeRate => new DailyExchangeRateDto(exchangeRate.Date, exchangeRate.ExchangeRate))
.ToListAsync(cancellationToken));
}
IEnumerable <NbpExchangeRateDailyQuery> ConvertGapPeriodsToNbpExchangeRateQueries
(List <DateTime> gapDays)
{
if (gapDays != null)
{
return(gapDays.Select(gapPeriod => new NbpExchangeRateDailyQuery(
request.CurrencyIsoCode,
gapPeriod.Date.ToString("yyyy-MM-dd")
)));
}
return(Enumerable.Empty <NbpExchangeRateDailyQuery>());
}
async Task SaveNbpExchangeRateModels(NbpExchangeRateModel nbpExchangeRateModel)
{
if (nbpExchangeRateModel != null && nbpExchangeRateModel.NotEmpty())
{
foreach (var dailyExchangeRateFromNbp in nbpExchangeRateModel.Rates)
{
var date = DateTime.Parse(dailyExchangeRateFromNbp.EffectiveDate);
var currencyId = (await databaseContext.Currency
.FirstAsync(currency => currency.IsoCode == request.CurrencyIsoCode, cancellationToken)).Id;
var dailyExchangeRate = DailyExchangeRate.Create(dailyExchangeRateFromNbp.No,
date, dailyExchangeRateFromNbp.Mid, currencyId);
databaseContext.DailyExchangeRate.Add(dailyExchangeRate);
}
await databaseContext.SaveChangesAsync(cancellationToken);
}
}
#endregion
}
