// Summary:
// Get the current exchange rate from the API repository and converts as ShowConversionDto.
//
// Parameters:
// createConversionDto:
// An instance to CreateConversionDto.
// Return:
// showConversionDto
// An instance to ShowConversionDto
private async Task <ShowConversionDto> CalculateValue(CreateConversionDto createConversionDto)
{
LatestExchangeRates latestExchangeRates = await _currencyRepository.GetLatestConversionRatesByCurrency("EUR");
ShowConversionDto showConversionDto = new ShowConversionDto(createConversionDto.FromCurrency, createConversionDto.ToCurrency, createConversionDto.Value);
showConversionDto.ExchangeRate = CalculateExchangeRateValue(showConversionDto, latestExchangeRates);
return(showConversionDto);
}
// Summary:
// Manually converting and mapping the exchange rates from default base currency vaalue to the target currency.
//
// Parameters:
// LatestExchangeRates:
// An instance to LatestExchangeRates.
// ShowConversionDto:
// An instance to ShowConversionDto.
// Return:
// float
// Converted final exchange rate
private float CalculateExchangeRateValue(ShowConversionDto showConversionDto, LatestExchangeRates latestExchangeRates)
{
float fromVsBaseExchangeRate = showConversionDto.FromCurrency == latestExchangeRates.Base ? 1 : FindExchangeRate(latestExchangeRates, showConversionDto.FromCurrency);
float baseVsToExchangeRate = showConversionDto.ToCurrency == latestExchangeRates.Base ? 1 : FindExchangeRate(latestExchangeRates, showConversionDto.ToCurrency);
if (fromVsBaseExchangeRate > 0 && baseVsToExchangeRate > 0)
{
float finalExchangeRate = (1 / fromVsBaseExchangeRate) * baseVsToExchangeRate;
return(finalExchangeRate);
}
throw new NotSupportedException($"Conversion from {showConversionDto.FromCurrency} to {showConversionDto.ToCurrency} is not supported at the moment");
}
public async Task <ActionResult <ShowConversionDto> > ConvertSourceToDestinationCurrency([FromBody] CreateConversionDto createConversionDto)
{
try
{
ShowConversionDto showConversionDto = await this._currencyService.Convert(createConversionDto);
if (showConversionDto.FromCurrency is null)
{
// need to log
return(NotFound());
}
return(Ok(showConversionDto));
}
catch (Exception)
{
// need to log
return(NotFound());
}
}
// Summary:
// It internally converts the base currency to the targer currency since API only supports EUR
//
// Parameters:
// latestExchangeRates:
// An instance to LatestExchangeRates
// string:
// Currency code.
// Return:
// showExchangeRateDto
// An instance to ShowExchangeRateDto
private ShowExchangeRateDto ConvertAsBaseCurrency(LatestExchangeRates latestExchangeRates, string currencyCode)
{
ShowExchangeRateDto convertedRates = new ShowExchangeRateDto()
{
Base = currencyCode,
Timestamp = latestExchangeRates.Timestamp,
Date = latestExchangeRates.Date,
Rates = new Dictionary <string, float>()
};
if (latestExchangeRates.Base == currencyCode)
{
convertedRates.Rates = latestExchangeRates.Rates;
return(convertedRates);
}
foreach (KeyValuePair <string, float> entry in latestExchangeRates.Rates.ToList())
{
ShowConversionDto showConversionDto = new ShowConversionDto(currencyCode, entry.Key, 0);
convertedRates.Rates.Add(entry.Key, CalculateExchangeRateValue(showConversionDto, latestExchangeRates));
}
return(convertedRates);
}
// Summary:
// It will convert the given value from source currency to target
//
// Parameters:
// createConversionDto:
// An instance to CreateConversionDto.
// Return:
// showConversionDto
// An instance to ShowConversionDto
public async Task <ShowConversionDto> Convert(CreateConversionDto createConversionDto)
{
ShowConversionDto showConversionDto = await CalculateValue(createConversionDto);
return(showConversionDto);
}
