wpa_supplicant: Reuse existing networks and preserve saved ones on connect

Connect() called AddNetwork unconditionally, creating duplicate entries for
the same SSID, and SelectNetwork's side-effect of disabling all other
networks was being persisted by SaveConfig — making previously saved
networks appear erased. Disconnect() also removed the current network from
the config. Now reuse an existing network entry when the SSID matches,
re-enable other networks after SelectNetwork, and keep entries on
disconnect.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

internal/wifi/wpasupplicant/backend.go

@@ -152,35 +152,69 @@ func (b *WPABackend) IsScanning() (bool, error) {
 
 // Connect connects to a WiFi network
 func (b *WPABackend) Connect(ssid, password string) error {
-	// Create network configuration
-	config := make(map[string]interface{})
-	config["ssid"] = ssid // Raw SSID string, no quotes
-
-	if password != "" {
-		// For WPA/WPA2-PSK networks
-		config["psk"] = password // Raw password string, no quotes
-	} else {
-		// For open networks
-		config["key_mgmt"] = "NONE"
-	}
-
-	// Add network
-	networkPath, err := b.iface.AddNetwork(config)
+	// Look up existing network with the same SSID to avoid creating duplicates
+	existingNetworks, err := b.iface.GetNetworks()
 	if err != nil {
-		return fmt.Errorf("failed to add network: %v", err)
+		return fmt.Errorf("failed to list configured networks: %v", err)
 	}
 
-	// Store current network path for cleanup
+	var networkPath dbus.ObjectPath
+	createdNew := false
+
+	for _, p := range existingNetworks {
+		net := NewNetwork(b.conn, p)
+		netSSID, err := net.GetSSID()
+		if err != nil || netSSID != ssid {
+			continue
+		}
+		networkPath = p
+		break
+	}
+
+	if networkPath == "" {
+		// Create network configuration
+		config := make(map[string]interface{})
+		config["ssid"] = ssid // Raw SSID string, no quotes
+
+		if password != "" {
+			// For WPA/WPA2-PSK networks
+			config["psk"] = password // Raw password string, no quotes
+		} else {
+			// For open networks
+			config["key_mgmt"] = "NONE"
+		}
+
+		networkPath, err = b.iface.AddNetwork(config)
+		if err != nil {
+			return fmt.Errorf("failed to add network: %v", err)
+		}
+		createdNew = true
+	}
+
+	// Store current network path
 	b.currentNetwork = networkPath
 
-	// Select (connect to) the network
+	// Select (connect to) the network. Note: SelectNetwork disables every
+	// other configured network as a side-effect.
 	err = b.iface.SelectNetwork(networkPath)
 	if err != nil {
-		// Clean up network on failure
-		b.iface.RemoveNetwork(networkPath)
+		if createdNew {
+			b.iface.RemoveNetwork(networkPath)
+		}
 		return fmt.Errorf("failed to select network: %v", err)
 	}
 
+	// Re-enable previously configured networks so SelectNetwork's side-effect
+	// doesn't mark them all as disabled in the persisted config.
+	for _, p := range existingNetworks {
+		if p == networkPath {
+			continue
+		}
+		if err := b.iface.EnableNetwork(p); err != nil {
+			fmt.Printf("Warning: failed to re-enable network %s: %v\n", p, err)
+		}
+	}
+
 	// Save the configuration to persist it across reboots
 	if err := b.iface.SaveConfig(); err != nil {
 		// Log warning but don't fail - connection still works
@@ -197,11 +231,7 @@ func (b *WPABackend) Disconnect() error {
 		return fmt.Errorf("failed to disconnect: %v", err)
 	}
 
-	// Remove the network configuration if we have one
-	if b.currentNetwork != "" && b.currentNetwork != "/" {
-		b.iface.RemoveNetwork(b.currentNetwork)
-		b.currentNetwork = ""
-	}
+	b.currentNetwork = ""
 
 	return nil
 }

internal/wifi/wpasupplicant/interface.go

@@ -107,6 +107,16 @@ func (i *WPAInterface) SelectNetwork(networkPath dbus.ObjectPath) error {
 	return nil
 }
 
+// EnableNetwork marks a network configuration as enabled (eligible for auto-connect)
+func (i *WPAInterface) EnableNetwork(networkPath dbus.ObjectPath) error {
+	netObj := i.conn.Object(Service, networkPath)
+	err := netObj.SetProperty(NetworkInterface+".Enabled", dbus.MakeVariant(true))
+	if err != nil {
+		return fmt.Errorf("failed to enable network: %v", err)
+	}
+	return nil
+}
+
 // RemoveNetwork removes a network configuration
 func (i *WPAInterface) RemoveNetwork(networkPath dbus.ObjectPath) error {
 	err := i.obj.Call(InterfaceInterface+".RemoveNetwork", 0, networkPath).Err
@@ -116,6 +126,21 @@ func (i *WPAInterface) RemoveNetwork(networkPath dbus.ObjectPath) error {
 	return nil
 }
 
+// GetNetworks returns the object paths of all configured networks
+func (i *WPAInterface) GetNetworks() ([]dbus.ObjectPath, error) {
+	prop, err := i.obj.GetProperty(InterfaceInterface + ".Networks")
+	if err != nil {
+		return nil, fmt.Errorf("failed to get Networks property: %v", err)
+	}
+
+	networks, ok := prop.Value().([]dbus.ObjectPath)
+	if !ok {
+		return nil, fmt.Errorf("Networks property is not an array of ObjectPath")
+	}
+
+	return networks, nil
+}
+
 // Disconnect disconnects from the current network
 func (i *WPAInterface) Disconnect() error {
 	err := i.obj.Call(InterfaceInterface+".Disconnect", 0).Err

internal/wifi/wpasupplicant/network.go

@@ -1,6 +1,8 @@
 package wpasupplicant
 
 import (
+	"strings"
+
 	"github.com/godbus/dbus/v5"
 )
 
@@ -39,3 +41,25 @@ func (n *Network) GetProperties() (map[string]dbus.Variant, error) {
 
 	return props, nil
 }
+
+// GetSSID returns the configured SSID, stripping the wrapping quotes
+// that wpa_supplicant stores around string-form SSIDs.
+func (n *Network) GetSSID() (string, error) {
+	props, err := n.GetProperties()
+	if err != nil {
+		return "", err
+	}
+
+	ssidVariant, ok := props["ssid"]
+	if !ok {
+		return "", nil
+	}
+
+	ssid, ok := ssidVariant.Value().(string)
+	if !ok {
+		return "", nil
+	}
+
+	// wpa_supplicant returns quoted SSIDs like "MyNetwork"
+	return strings.Trim(ssid, `"`), nil
+}