From dfca0079495d933e6393ebe636e42fcf8dd03bdd Mon Sep 17 00:00:00 2001
From: archipelago <archipelago@localhost>
Date: Tue, 30 Jun 2026 22:27:54 -0400
Subject: [PATCH] wip(mesh): parse MeshPacket rx_snr/rx_rssi fields (Meshtastic
 backlog #14, part 1/many)
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Field numbers confirmed against the canonical meshtastic/protobufs mesh.proto
(rx_snr=8 float, rx_rssi=12 int32), not guessed. Not yet threaded through to
ParsedContact/MeshPeer/mesh.peers — that's the next step. Part of the
Meshtastic 1.8.0 backlog plan (RSSI/SNR indicator, peer-location map, Device
tab, provisioning robustness, onboarding modal) — see
.claude/plans/floofy-riding-seahorse.md for the full plan.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
---
 core/archipelago/src/mesh/meshtastic.rs | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/core/archipelago/src/mesh/meshtastic.rs b/core/archipelago/src/mesh/meshtastic.rs
index 3fcaeedf..cffd34ed 100644
--- a/core/archipelago/src/mesh/meshtastic.rs
+++ b/core/archipelago/src/mesh/meshtastic.rs
@@ -1446,6 +1446,12 @@ struct ParsedPacket {
     pki_encrypted: bool,
     /// MeshPacket.public_key (field 16): the sender's key, carried on PKC DMs.
     public_key: Option<Vec<u8>>,
+    /// MeshPacket.rx_snr (field 8, float) — signal-to-noise ratio in dB, as
+    /// measured by the receiving radio. Field numbers confirmed against the
+    /// canonical `meshtastic/protobufs` mesh.proto, not guessed.
+    rx_snr: Option<f32>,
+    /// MeshPacket.rx_rssi (field 12, int32) — received signal strength in dBm.
+    rx_rssi: Option<i32>,
 }
 
 fn parse_mesh_packet(data: &[u8]) -> Option<ParsedPacket> {
@@ -1458,6 +1464,8 @@ fn parse_mesh_packet(data: &[u8]) -> Option<ParsedPacket> {
     let mut rx_time = None;
     let mut pki_encrypted = false;
     let mut public_key = None;
+    let mut rx_snr = None;
+    let mut rx_rssi = None;
     while idx < data.len() {
         let (field, value, next) = next_field(data, idx)?;
         idx = next;
@@ -1468,6 +1476,10 @@ fn parse_mesh_packet(data: &[u8]) -> Option<ParsedPacket> {
             (4, FieldValue::Bytes(b)) => decoded = Some(b),
             (6, FieldValue::Fixed32(v)) => id = Some(v),
             (7, FieldValue::Fixed32(v)) if v != 0 => rx_time = Some(v),
+            // float wire type (5) decodes as a 32-bit fixed value; reinterpret
+            // the bits as f32 rather than treating them as an integer.
+            (8, FieldValue::Fixed32(v)) => rx_snr = Some(f32::from_bits(v)),
+            (12, FieldValue::Varint(v)) => rx_rssi = Some(v as i32),
             (16, FieldValue::Bytes(b)) if !b.is_empty() => public_key = Some(b.to_vec()),
             (17, FieldValue::Varint(v)) => pki_encrypted = v != 0,
             _ => {}
@@ -1496,6 +1508,8 @@ fn parse_mesh_packet(data: &[u8]) -> Option<ParsedPacket> {
         rx_time,
         pki_encrypted,
         public_key,
+        rx_snr,
+        rx_rssi,
     })
 }