Update project structure and build process

libwallet/invoice.go

@@ -0,0 +1,83 @@
+package libwallet
+
+import (
+	"fmt"
+
+	"github.com/lightningnetwork/lnd/zpay32"
+	"github.com/muun/libwallet/errors"
+)
+
+// Invoice is muun's invoice struct
+type Invoice struct {
+	RawInvoice      string
+	FallbackAddress *MuunPaymentURI
+	Network         *Network
+	MilliSat        string
+	Destination     []byte
+	PaymentHash     []byte
+	Expiry          int64
+	Description     string
+	Sats            int64
+}
+
+const lightningScheme = "lightning:"
+
+// ParseInvoice parses an Invoice from an invoice string and a network
+func ParseInvoice(rawInput string, network *Network) (*Invoice, error) {
+
+	_, components := buildUriFromString(rawInput, lightningScheme)
+	if components == nil {
+		return nil, errors.Errorf(ErrInvalidInvoice, "failed to parse uri %v", rawInput)
+	}
+
+	if components.Scheme != "lightning" {
+		return nil, errors.Errorf(ErrInvalidInvoice, "invalid scheme %v", components.Scheme)
+	}
+
+	invoice := components.Opaque
+
+	// When URIs are scheme:// the address comes in host
+	// this happens in iOS that mostly ignores scheme: format
+	if len(invoice) == 0 {
+		invoice = components.Host
+	}
+
+	parsedInvoice, err := zpay32.Decode(invoice, network.network)
+	if err != nil {
+		return nil, errors.Errorf(ErrInvalidInvoice, "Couldn't parse invoice: %w", err)
+	}
+
+	var fallbackAdd *MuunPaymentURI
+
+	if parsedInvoice.FallbackAddr != nil {
+		fallbackAdd, err = GetPaymentURI(parsedInvoice.FallbackAddr.String(), network)
+		if err != nil {
+			return nil, errors.Errorf(ErrInvalidInvoice, "Couldn't get address: %w", err)
+		}
+	}
+
+	var description string
+	if parsedInvoice.Description != nil {
+		description = *parsedInvoice.Description
+	}
+
+	var milliSats string
+	var sats int64
+	if parsedInvoice.MilliSat != nil {
+		milliSat := uint64(*parsedInvoice.MilliSat)
+		milliSats = fmt.Sprintf("%v", milliSat)
+		sats = int64(milliSat / 1000)
+	}
+
+	return &Invoice{
+		RawInvoice:      invoice,
+		FallbackAddress: fallbackAdd,
+		Network:         network,
+		MilliSat:        milliSats,
+		Destination:     parsedInvoice.Destination.SerializeCompressed(),
+		PaymentHash:     parsedInvoice.PaymentHash[:],
+		Expiry:          parsedInvoice.Timestamp.Unix() + int64(parsedInvoice.Expiry().Seconds()),
+		Description:     description,
+		Sats:            sats,
+	}, nil
+}