From de24a6e71b3f14272a803f74563ea2b9689c5cec Mon Sep 17 00:00:00 2001
From: Dennis Reimann <mail@dennisreimann.de>
Date: Fri, 12 Aug 2022 20:10:44 +0200
Subject: [PATCH] LNURL controller refactoring

By moving the `amount is null` check up, this prevents cases in which the `paymentMethodDetails.GeneratedBoltAmount != amount` check fails because of amount being null.
---
 BTCPayServer/Controllers/UILNURLController.cs | 32 +++++++++----------
 1 file changed, 16 insertions(+), 16 deletions(-)

diff --git a/BTCPayServer/Controllers/UILNURLController.cs b/BTCPayServer/Controllers/UILNURLController.cs
index af40d3f17..a3c2c4138 100644
--- a/BTCPayServer/Controllers/UILNURLController.cs
+++ b/BTCPayServer/Controllers/UILNURLController.cs
@@ -524,8 +524,21 @@ namespace BTCPayServer
                             Url = _linkGenerator.GetUriByAction(HttpContext, "InvoiceReceipt", "UIInvoice", new { invoiceId})
                         };
                 }
-                if (amount.HasValue && string.IsNullOrEmpty(paymentMethodDetails.BOLT11) ||
-                    paymentMethodDetails.GeneratedBoltAmount != amount)
+
+                if (amount is null)
+                {
+                    return Ok(new LNURLPayRequest
+                    {
+                        Tag = "payRequest",
+                        MinSendable = min,
+                        MaxSendable = max,
+                        CommentAllowed = lnurlSupportedPaymentMethod.LUD12Enabled ? 2000 : 0,
+                        Metadata = metadata,
+                        Callback = new Uri(Request.GetCurrentUrl())
+                    });
+                }
+                
+                if (string.IsNullOrEmpty(paymentMethodDetails.BOLT11) || paymentMethodDetails.GeneratedBoltAmount != amount)
                 {
                     var client =
                         _lightningLikePaymentHandler.CreateLightningClient(
@@ -589,7 +602,7 @@ namespace BTCPayServer
                     });
                 }
 
-                if (amount.HasValue && paymentMethodDetails.GeneratedBoltAmount == amount)
+                if (paymentMethodDetails.GeneratedBoltAmount == amount)
                 {
                     if (lnurlSupportedPaymentMethod.LUD12Enabled && paymentMethodDetails.ProvidedComment != comment)
                     {
@@ -604,19 +617,6 @@ namespace BTCPayServer
                         SuccessAction = successAction
                     });
                 }
-
-                if (amount is null)
-                {
-                    return Ok(new LNURLPayRequest
-                    {
-                        Tag = "payRequest",
-                        MinSendable = min,
-                        MaxSendable = max,
-                        CommentAllowed = lnurlSupportedPaymentMethod.LUD12Enabled ? 2000 : 0,
-                        Metadata = metadata,
-                        Callback = new Uri(Request.GetCurrentUrl())
-                    });
-                }
             }
 
             return BadRequest(new LNUrlStatusResponse