routing+channeldb: add more failure reasons

channeldb/payments.go

@@ -94,10 +94,17 @@ const (
 	// destination was found during path finding.
 	FailureReasonNoRoute FailureReason = 1
 
+	// FailureReasonError indicates that an unexpected error happened during
+	// payment.
+	FailureReasonError FailureReason = 2
+
+	// FailureReasonIncorrectPaymentDetails indicates that either the hash
+	// is unknown or the final cltv delta or amount is incorrect.
+	FailureReasonIncorrectPaymentDetails FailureReason = 3
+
 	// TODO(halseth): cancel state.
 
 	// TODO(joostjager): Add failure reasons for:
-	// UnknownPaymentHash, FinalInvalidAmt, FinalInvalidCltv
 	// LocalLiquidityInsufficient, RemoteCapacityInsufficient.
 )
 
@@ -108,6 +115,10 @@ func (r FailureReason) String() string {
 		return "timeout"
 	case FailureReasonNoRoute:
 		return "no_route"
+	case FailureReasonError:
+		return "error"
+	case FailureReasonIncorrectPaymentDetails:
+		return "incorrect_payment_details"
 	}
 
 	return "unknown"