From ed326255d545af528d734dfb8c821c322b8eeb40 Mon Sep 17 00:00:00 2001
From: liamcottle <liam@liamcottle.com>
Date: Mon, 23 Mar 2026 21:46:21 +1300
Subject: [PATCH] add support for direct paths when sending group data

---
 examples/companion_radio/MyMesh.cpp | 17 ++++++++++++++++-
 src/helpers/BaseChatMesh.cpp        | 10 ++++++++--
 src/helpers/BaseChatMesh.h          |  2 +-
 3 files changed, 25 insertions(+), 4 deletions(-)

diff --git a/examples/companion_radio/MyMesh.cpp b/examples/companion_radio/MyMesh.cpp
index a98d4b6a..f151fb30 100644
--- a/examples/companion_radio/MyMesh.cpp
+++ b/examples/companion_radio/MyMesh.cpp
@@ -1110,6 +1110,21 @@ void MyMesh::handleCmdFrame(size_t len) {
     uint16_t data_type = ((uint16_t)cmd_frame[i]) | (((uint16_t)cmd_frame[i + 1]) << 8);
     i += 2;
     uint8_t channel_idx = cmd_frame[i++];
+    uint8_t path_len = cmd_frame[i++];
+
+    // validate path len, allowing 0xFF for flood
+    if (!mesh::Packet::isValidPathLen(path_len) && path_len != OUT_PATH_UNKNOWN) {
+      MESH_DEBUG_PRINTLN("CMD_SEND_CHANNEL_DATA invalid path size: %d", path_len);
+      writeErrFrame(ERR_CODE_ILLEGAL_ARG);
+      return;
+    }
+
+    // parse provided path if not flood
+    uint8_t path[MAX_PATH_SIZE];
+    if (path_len != OUT_PATH_UNKNOWN) {
+      i += mesh::Packet::writePath(path, &cmd_frame[i], path_len);
+    }
+
     const uint8_t *payload = &cmd_frame[i];
     int payload_len = (len > (size_t)i) ? (int)(len - i) : 0;
 
@@ -1121,7 +1136,7 @@ void MyMesh::handleCmdFrame(size_t len) {
     } else if (payload_len > MAX_CHANNEL_DATA_LENGTH) {
       MESH_DEBUG_PRINTLN("CMD_SEND_CHANNEL_DATA payload too long: %d > %d", payload_len, MAX_CHANNEL_DATA_LENGTH);
       writeErrFrame(ERR_CODE_ILLEGAL_ARG);
-    } else if (sendGroupData(channel.channel, data_type, payload, payload_len)) {
+    } else if (sendGroupData(channel.channel, path, path_len, data_type, payload, payload_len)) {
       writeOKFrame();
     } else {
       writeErrFrame(ERR_CODE_TABLE_FULL);
diff --git a/src/helpers/BaseChatMesh.cpp b/src/helpers/BaseChatMesh.cpp
index 78e197be..7ddc461d 100644
--- a/src/helpers/BaseChatMesh.cpp
+++ b/src/helpers/BaseChatMesh.cpp
@@ -481,7 +481,7 @@ bool BaseChatMesh::sendGroupMessage(uint32_t timestamp, mesh::GroupChannel& chan
   return false;
 }
 
-bool BaseChatMesh::sendGroupData(mesh::GroupChannel& channel, uint16_t data_type, const uint8_t* data, int data_len) {
+bool BaseChatMesh::sendGroupData(mesh::GroupChannel& channel, uint8_t* path, uint8_t path_len, uint16_t data_type, const uint8_t* data, int data_len) {
   if (data_len < 0) {
     MESH_DEBUG_PRINTLN("sendGroupData: invalid negative data_len=%d", data_len);
     return false;
@@ -502,7 +502,13 @@ bool BaseChatMesh::sendGroupData(mesh::GroupChannel& channel, uint16_t data_type
     MESH_DEBUG_PRINTLN("sendGroupData: unable to create group datagram, data_len=%d", data_len);
     return false;
   }
-  sendFloodScoped(channel, pkt);
+
+  if (path_len == OUT_PATH_UNKNOWN) {
+    sendFloodScoped(channel, pkt);
+  } else {
+    sendDirect(pkt, path, path_len);
+  }
+
   return true;
 }
 
diff --git a/src/helpers/BaseChatMesh.h b/src/helpers/BaseChatMesh.h
index c2f9d915..b39e7363 100644
--- a/src/helpers/BaseChatMesh.h
+++ b/src/helpers/BaseChatMesh.h
@@ -150,7 +150,7 @@ public:
   int  sendMessage(const ContactInfo& recipient, uint32_t timestamp, uint8_t attempt, const char* text, uint32_t& expected_ack, uint32_t& est_timeout);
   int  sendCommandData(const ContactInfo& recipient, uint32_t timestamp, uint8_t attempt, const char* text, uint32_t& est_timeout);
   bool sendGroupMessage(uint32_t timestamp, mesh::GroupChannel& channel, const char* sender_name, const char* text, int text_len);
-  bool sendGroupData(mesh::GroupChannel& channel, uint16_t data_type, const uint8_t* data, int data_len);
+  bool sendGroupData(mesh::GroupChannel& channel, uint8_t* path, uint8_t path_len, uint16_t data_type, const uint8_t* data, int data_len);
   int  sendLogin(const ContactInfo& recipient, const char* password, uint32_t& est_timeout);
   int  sendAnonReq(const ContactInfo& recipient, const uint8_t* data, uint8_t len, uint32_t& tag, uint32_t& est_timeout);
   int  sendRequest(const ContactInfo& recipient, uint8_t req_type, uint32_t& tag, uint32_t& est_timeout);