39 lines
1.2 KiB
Go
39 lines
1.2 KiB
Go
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package utils
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import (
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"fmt"
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"math"
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"github.com/danilsolovyov/croupierCbrf/dal"
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)
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func CurrencyExchange(currencies map[string]dal.Quote, fromCurrency, toCurrency string, amount int64) (int64, error) {
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fromRate, ok := currencies[fromCurrency]
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if !ok && fromCurrency != dal.DefaultCurrency {
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return 0, fmt.Errorf("Курс для валюты %s не найден", fromCurrency)
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}
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if fromCurrency == dal.DefaultCurrency {
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fromRate.Value = 1
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}
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toRate, ok := currencies[toCurrency]
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if !ok && toCurrency != dal.DefaultCurrency {
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return 0, fmt.Errorf("Курс для валюты %s не найден", toCurrency)
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}
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if toCurrency == dal.DefaultCurrency {
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toRate.Value = 1
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}
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// Округляем число курса 79.9093 => 79.91
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roundedFromValue := math.Round(fromRate.Value*100) / 100
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roundedToValue := math.Round(toRate.Value*100) / 100
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// Переводим сумму из одной валюты в рубли
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amountInRubles := float64(amount) * roundedFromValue
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// Переводим рубли в нужную валюту и округляем до ближайшего целого числа
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result := int64(amountInRubles / roundedToValue)
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return result, nil
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}
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