From 8dddb5d5389efac0c661bb5f47645bf679299bea Mon Sep 17 00:00:00 2001
From: f321x <f@f321x.com>
Date: Wed, 4 Mar 2026 17:11:47 +0100
Subject: [PATCH] plugin: nwc: unify budget_allows_spend and add_to_budget

There is now only add_to_budget which will return None if the budget
doesn't allow for this spend. It will always add the spend to the
budget, even if the user has no budget so it can be used for display
purposes (and simpler code, only one path).
---
 electrum/plugins/nwc/nwcserver.py | 37 +++++++++++++------------------
 1 file changed, 16 insertions(+), 21 deletions(-)

diff --git a/electrum/plugins/nwc/nwcserver.py b/electrum/plugins/nwc/nwcserver.py
index c0682c382..a050746c2 100644
--- a/electrum/plugins/nwc/nwcserver.py
+++ b/electrum/plugins/nwc/nwcserver.py
@@ -816,9 +816,9 @@ class NWCServer(Logger, EventListener):
         elif invoice.get_amount_msat() is None:
             invoice.set_amount_msat(amount_msat)
 
-        if not self.budget_allows_spend(request_pub, msat_requested=amount_msat or invoice.get_amount_msat()):
+        budget_item = self.add_to_budget(request_pub, msat_requested=amount_msat or invoice.get_amount_msat())
+        if not budget_item:
             return self.get_error_response("QUOTA_EXCEEDED", "Payment exceeds daily limit")
-        budget_item = self.add_to_budget(request_pub, amount_msat=amount_msat or invoice.get_amount_msat())
 
         self.wallet.save_invoice(invoice)
         success = None
@@ -848,18 +848,6 @@ class NWCServer(Logger, EventListener):
             self.logger.info(f"failed to pay invoice request from NWC: {log}")
         return response
 
-    def add_to_budget(self, client_pub: str, *, amount_msat: int) -> list[int]:
-        """
-        If client_pub has a budget, check if the amount is within the budget and add it to the budget.
-        Return True if the payment is allowed (within the budget)
-        """
-        if 'budget_spends' not in self.connections[client_pub]:
-            self.connections[client_pub]['budget_spends'] = []
-        # tuples don't work because jsondb converts them to lists on reload
-        budget_item = [amount_msat, int(time.time())]
-        self.connections[client_pub]['budget_spends'].append(budget_item)
-        return budget_item
-
     def remove_from_budget(self, client_pub: str, budget_item: list[int]) -> None:
         assert len(budget_item) == 2, budget_item
         budget_spends = self.connections[client_pub].get('budget_spends', [])
@@ -888,14 +876,21 @@ class NWCServer(Logger, EventListener):
                     continue  # could happen if there is a race
         return used_budget
 
-    def budget_allows_spend(self, client_pub: str, *, msat_requested: int) -> bool:
+    def add_to_budget(self, client_pub: str, *, msat_requested: int) -> Optional[list[int]]:
+        if 'budget_spends' not in self.connections[client_pub]:
+            self.connections[client_pub]['budget_spends'] = []
+
+        # check if budget allows this spend
         client_budget_sat: Optional[int] = self.connections[client_pub].get('daily_limit_sat')
-        if client_budget_sat is None:
-            return True  # unlimited budget
-        used_budget_msat: int = self.get_used_budget_msat(client_pub)
-        if used_budget_msat + msat_requested > client_budget_sat * 1000:
-            return False
-        return True
+        if client_budget_sat is not None:
+            used_budget_msat: int = self.get_used_budget_msat(client_pub)
+            if used_budget_msat + msat_requested > client_budget_sat * 1000:
+                return None
+
+        # tuples don't work because jsondb converts them to lists on reload
+        budget_item = [msat_requested, int(time.time())]
+        self.connections[client_pub]['budget_spends'].append(budget_item)
+        return budget_item
 
     async def publish_info_event(self):
         """