Bootstrap copied BFF and local accounts with public Sendico contracts (#34)

backend/pkg/model/currency.go

@@ -0,0 +1,77 @@
+package model
+
+import (
+	"sort"
+	"strings"
+
+	"git.sendico.io/tech/sxchnge/bff/pkg/merrors"
+	"git.sendico.io/tech/sxchnge/bff/pkg/moneybase"
+)
+
+type Currency string
+
+const (
+	CurrencyEUR  Currency = "EUR"  // Euro
+	CurrencyUSD  Currency = "USD"  // US Dollar
+	CurrencyRUB  Currency = "RUB"  // Russian Ruble
+	CurrencyUAH  Currency = "UAH"  // Ukrainian Hryvnia
+	CurrencyPLN  Currency = "PLN"  // Polish Złoty
+	CurrencyCZK  Currency = "CZK"  // Czech Koruna
+	CurrencyUSDT Currency = "USDT" // Tether USD
+)
+
+const MaxCurrencyScale uint32 = moneybase.MaxScale
+
+func NormalizeCurrency(value string) Currency {
+	return Currency(strings.ToUpper(strings.TrimSpace(value)))
+}
+
+func NormalizeExplicitCurrencyScales(values map[Currency]uint32) (map[Currency]uint32, error) {
+	if len(values) == 0 {
+		return nil, merrors.InvalidArgument("currency scales are required")
+	}
+	out := make(map[Currency]uint32, len(values))
+	for rawCurrency, scale := range values {
+		currency := NormalizeCurrency(string(rawCurrency))
+		if currency == "" {
+			return nil, merrors.InvalidArgument("currency scale key is required")
+		}
+		if scale > MaxCurrencyScale {
+			return nil, merrors.InvalidArgumentf("currency scale for %s exceeds %d", currency, MaxCurrencyScale)
+		}
+		out[currency] = scale
+	}
+	return out, nil
+}
+
+func CurrencyScale(scales map[Currency]uint32, currency string) (uint32, error) {
+	normalized := NormalizeCurrency(currency)
+	if normalized == "" {
+		return 0, merrors.InvalidArgument("currency is required")
+	}
+	if scales == nil {
+		return 0, merrors.InvalidArgument("currency scale map is required")
+	}
+	scale, ok := scales[normalized]
+	if !ok {
+		return 0, merrors.InvalidArgument("currency scale for " + string(normalized) + " is not configured")
+	}
+	return scale, nil
+}
+
+func CurrencyScaleKeys(scales map[Currency]uint32) []string {
+	if scales == nil {
+		return nil
+	}
+	keys := make([]string, 0, len(scales))
+	for currency := range scales {
+		keys = append(keys, string(currency))
+	}
+	sort.Strings(keys)
+	return keys
+}
+
+type Amount struct {
+	Total    float64  `bson:"total" json:"total"`       // Total amount billed
+	Currency Currency `bson:"currency" json:"currency"` // Currency for the invoice
+}