feat(hci): enhance connection queue to support multiple devices

lib/hci-socket/bindings.js

@@ -61,20 +61,26 @@ NobleBindings.prototype.connect = function (peripheralUuid, parameters = {}) {
     addressType = parameters && parameters.addressType ? parameters.addressType : 'random';
   }
 
-  const createConnection = () => {
-    if (!this._pendingConnectionUuid) {
-      this._pendingConnectionUuid = peripheralUuid;
-      this._hci.createLeConn(address, addressType, parameters);
-    } else {
-      this._connectionQueue.push({ id: peripheralUuid, params: parameters });
-    }
+  // Add connection request to queue
+  this._connectionQueue.push({ 
+    id: peripheralUuid, 
+    address, 
+    addressType, 
+    params: parameters 
+  });
+
+  const processNextConnection = () => {
+    if (this._connectionQueue.length === 0) return;
+
+    const nextConn = this._connectionQueue[0]; // Look at next connection but don't remove yet
+    this._hci.createLeConn(nextConn.address, nextConn.addressType, nextConn.params);
   };
 
   if (this._isScanning) {
-    this.once('scanStop', createConnection);
+    this.once('scanStop', processNextConnection);
     this.stopScanning();
   } else {
-    createConnection();
+    processNextConnection();
   }
 };
 
@@ -128,6 +134,21 @@ NobleBindings.prototype.onSigInt = function () {
   const sigIntListeners = process.listeners('SIGINT');
 
   if (sigIntListeners[sigIntListeners.length - 1] === this.onSigIntBinded) {
+    // Stop scanning if active
+    if (this._isScanning) {
+      this.stopScanning();
+    }
+
+    // Disconnect all active connections
+    for (const handle in this._handles) {
+      if (this._handles.hasOwnProperty(handle)) {
+        this.disconnect(this._handles[handle]);
+      }
+    }
+
+    // Clear connection queue
+    this._connectionQueue = [];
+
     // we are the last listener, so exit
     // this will trigger onExit, and clean up
     process.exit(1);
@@ -259,8 +280,8 @@ NobleBindings.prototype.onLeConnComplete = function (
     // not master, ignore
     return;
   }
-  let uuid = null;
 
+  let uuid = null;
   let error = null;
 
   if (status === 0) {
@@ -351,27 +372,23 @@ NobleBindings.prototype.onLeConnComplete = function (
 
     this._gatts[handle].exchangeMtu();
   } else {
-    uuid = this._pendingConnectionUuid;
+    const currentConn = this._connectionQueue[0];
+    uuid = currentConn ? currentConn.id : null;
     let statusMessage = Hci.STATUS_MAPPER[status] || 'HCI Error: Unknown';
     const errorCode = ` (0x${status.toString(16)})`;
     statusMessage = statusMessage + errorCode;
     error = new Error(statusMessage);
   }
 
-  this.emit('connect', uuid, error);
-
-  if (this._connectionQueue.length > 0) {
-    const queueItem = this._connectionQueue.shift();
-    const peripheralUuid = queueItem.id;
+  // Remove the completed/failed connection attempt from queue
+  this._connectionQueue.shift();
 
-    address = this._addresses[peripheralUuid];
-    addressType = this._addresseTypes[peripheralUuid];
-
-    this._pendingConnectionUuid = peripheralUuid;
+  this.emit('connect', uuid, error);
 
-    this._hci.createLeConn(address, addressType, queueItem.params);
-  } else {
-    this._pendingConnectionUuid = null;
+  // Process next connection in queue if any
+  if (this._connectionQueue.length > 0 && !this._isScanning) {
+    const nextConn = this._connectionQueue[0];
+    this._hci.createLeConn(nextConn.address, nextConn.addressType, nextConn.params);
   }
 };