From fdbd642e0e3bc1d4bcf14048d308e9d482514162 Mon Sep 17 00:00:00 2001
From: Ben Meadors <benmmeadors@gmail.com>
Date: Fri, 23 Jan 2026 13:54:20 -0600
Subject: [PATCH] Move preset coercion logic to RadioInterface

---
 src/mesh/NodeDB.cpp         | 25 ++-----------------------
 src/mesh/RadioInterface.cpp | 28 ++++++++++++++++++++++++++++
 src/mesh/RadioInterface.h   |  9 +++++++++
 3 files changed, 39 insertions(+), 23 deletions(-)

diff --git a/src/mesh/NodeDB.cpp b/src/mesh/NodeDB.cpp
index 2770f8cd8..f87fa58b1 100644
--- a/src/mesh/NodeDB.cpp
+++ b/src/mesh/NodeDB.cpp
@@ -13,6 +13,7 @@
 #include "PacketHistory.h"
 #include "PowerFSM.h"
 #include "RTC.h"
+#include "RadioInterface.h"
 #include "Router.h"
 #include "SPILock.h"
 #include "SafeFile.h"
@@ -1301,29 +1302,7 @@ void NodeDB::loadFromDisk()
     // Coerce LoRa config fields derived from presets while bootstrapping.
     // Some clients/UI components display bandwidth/spread_factor directly from config even in preset mode.
     if (config.has_lora && config.lora.use_preset) {
-        auto regionForCode = [](meshtastic_Config_LoRaConfig_RegionCode code) -> const RegionInfo * {
-            const RegionInfo *r = regions;
-            for (; r->code != meshtastic_Config_LoRaConfig_RegionCode_UNSET && r->code != code; r++)
-                ;
-            return r;
-        };
-
-        const RegionInfo *r = regionForCode(config.lora.region);
-        const bool wideLora = r ? r->wideLora : false;
-
-        float bwKHz = 0;
-        uint8_t sf = 0;
-        uint8_t cr = 0;
-        modemPresetToParams(config.lora.modem_preset, wideLora, bwKHz, sf, cr);
-
-        // If selected preset requests a bandwidth larger than the region span, fall back to LONG_FAST.
-        if (r && (r->freqEnd - r->freqStart) < (bwKHz / 1000.0f)) {
-            config.lora.modem_preset = meshtastic_Config_LoRaConfig_ModemPreset_LONG_FAST;
-            modemPresetToParams(config.lora.modem_preset, wideLora, bwKHz, sf, cr);
-        }
-
-        config.lora.bandwidth = bwKHzToCode(bwKHz);
-        config.lora.spread_factor = sf;
+        RadioInterface::bootstrapLoRaConfigFromPreset(config.lora);
     }
 
     if (backupSecurity.private_key.size > 0) {
diff --git a/src/mesh/RadioInterface.cpp b/src/mesh/RadioInterface.cpp
index 101347b11..f2ee0defe 100644
--- a/src/mesh/RadioInterface.cpp
+++ b/src/mesh/RadioInterface.cpp
@@ -220,6 +220,34 @@ void initRegion()
     myRegion = r;
 }
 
+void RadioInterface::bootstrapLoRaConfigFromPreset(meshtastic_Config_LoRaConfig &loraConfig)
+{
+    if (!loraConfig.use_preset) {
+        return;
+    }
+
+    // Find region info to determine whether "wide" LoRa is permitted (2.4 GHz uses wider bandwidth codes).
+    const RegionInfo *r = regions;
+    for (; r->code != meshtastic_Config_LoRaConfig_RegionCode_UNSET && r->code != loraConfig.region; r++)
+        ;
+
+    const bool wideLora = r ? r->wideLora : false;
+
+    float bwKHz = 0;
+    uint8_t sf = 0;
+    uint8_t cr = 0;
+    modemPresetToParams(loraConfig.modem_preset, wideLora, bwKHz, sf, cr);
+
+    // If selected preset requests a bandwidth larger than the region span, fall back to LONG_FAST.
+    if (r && (r->freqEnd - r->freqStart) < (bwKHz / 1000.0f)) {
+        loraConfig.modem_preset = meshtastic_Config_LoRaConfig_ModemPreset_LONG_FAST;
+        modemPresetToParams(loraConfig.modem_preset, wideLora, bwKHz, sf, cr);
+    }
+
+    loraConfig.bandwidth = bwKHzToCode(bwKHz);
+    loraConfig.spread_factor = sf;
+}
+
 /**
  * ## LoRaWAN for North America
 
diff --git a/src/mesh/RadioInterface.h b/src/mesh/RadioInterface.h
index 6049a11cc..8cead1761 100644
--- a/src/mesh/RadioInterface.h
+++ b/src/mesh/RadioInterface.h
@@ -7,6 +7,9 @@
 #include "airtime.h"
 #include "error.h"
 
+// Forward decls to avoid pulling generated config headers into this widely-included file.
+typedef struct _meshtastic_Config_LoRaConfig meshtastic_Config_LoRaConfig;
+
 #define MAX_TX_QUEUE 16 // max number of packets which can be waiting for transmission
 
 #define MAX_LORA_PAYLOAD_LEN 255 // max length of 255 per Semtech's datasheets on SX12xx
@@ -115,6 +118,12 @@ class RadioInterface
 
     virtual ~RadioInterface() {}
 
+    /**
+     * Coerce LoRa config fields (bandwidth/spread_factor) derived from presets.
+     * This is used during early bootstrapping so UIs that display these fields directly remain consistent.
+     */
+    static void bootstrapLoRaConfigFromPreset(meshtastic_Config_LoRaConfig &loraConfig);
+
     /**
      * Return true if we think the board can go to sleep (i.e. our tx queue is empty, we are not sending or receiving)
      *