fix(datastore): resolve local data directory using MAC address mapping

Fixes an issue where device data (e.g., Presets.xml) could not be located when accessed via MAC address because the internal directory structure is organized by serial number.

- Add a `macToSerial` mapping in `DataStore` to bridge MAC addresses from API requests to internal serial-numbered directories.
- Implement automatic mapping population during `DataStore` initialization by scanning `DeviceInfo.xml` files.
- Update `AccountDeviceDir` to transparently resolve MAC addresses to serial numbers for file path construction.
- Enhance UPnP discovery to capture the MAC address (as `serialNumber` in the device description) for better device identification.
- Include automated tests for MAC-to-serial resolution and UPnP enrichment.

pkg/discovery/upnp.go

@@ -2,8 +2,10 @@ package discovery
 
 import (
 	"context"
+	"encoding/xml"
 	"errors"
 	"fmt"
+	"io"
 	"log"
 	"net"
 	"net/http"
@@ -418,7 +420,7 @@ func (d *Service) parseLocationURL(location, usn string) (*models.DiscoveredDevi
 }
 
 // enrichDeviceInfo tries to get additional device information from the device description
-func (d *Service) enrichDeviceInfo(_ *models.DiscoveredDevice, location string) error {
+func (d *Service) enrichDeviceInfo(device *models.DiscoveredDevice, location string) error {
 	log.Printf("UPnP: Attempting to enrich device info by fetching %s", location)
 
 	client := &http.Client{
@@ -437,8 +439,44 @@ func (d *Service) enrichDeviceInfo(_ *models.DiscoveredDevice, location string)
 
 	log.Printf("UPnP: Successfully fetched device description from %s (Status: %s)", location, resp.Status)
 
-	// For now, we'll keep it simple and not parse the full UPnP device description
-	// This can be enhanced later to extract more detailed device information
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("unexpected status code: %d", resp.StatusCode)
+	}
+
+	data, err := io.ReadAll(resp.Body)
+	if err != nil {
+		return fmt.Errorf("failed to read body: %w", err)
+	}
+
+	var upnpRoot struct {
+		XMLName xml.Name `xml:"root"`
+		Device  struct {
+			FriendlyName string `xml:"friendlyName"`
+			ModelName    string `xml:"modelName"`
+			SerialNumber string `xml:"serialNumber"`
+		} `xml:"device"`
+	}
+
+	if err := xml.Unmarshal(data, &upnpRoot); err != nil {
+		log.Printf("UPnP: Failed to parse device description from %s: %v", location, err)
+		return err
+	}
+
+	if upnpRoot.Device.FriendlyName != "" {
+		device.Name = upnpRoot.Device.FriendlyName
+	}
+
+	if upnpRoot.Device.ModelName != "" {
+		device.ModelID = upnpRoot.Device.ModelName
+	}
+
+	if upnpRoot.Device.SerialNumber != "" {
+		device.UPnPSerial = upnpRoot.Device.SerialNumber
+	}
+
+	log.Printf("UPnP: Enriched device info: Name='%s', Model='%s', UPnPSerial='%s'",
+		device.Name, device.ModelID, device.UPnPSerial)
+
 	return nil
 }
 

pkg/discovery/upnp_enrich_test.go

@@ -0,0 +1,88 @@
+package discovery
+
+import (
+	"encoding/xml"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+
+	"github.com/gesellix/bose-soundtouch/pkg/models"
+)
+
+func TestEnrichDeviceInfo(t *testing.T) {
+	// Mock UPnP device description XML
+	xmlData := `<?xml version="1.0" encoding="utf-8"?>
+<root xmlns="urn:schemas-upnp-org:device-1-0">
+    <device>
+        <friendlyName>Sound Machinery</friendlyName>
+        <modelName>SoundTouch 10</modelName>
+        <serialNumber>A81B6A536A09</serialNumber>
+    </device>
+</root>`
+
+	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		w.Header().Set("Content-Type", "text/xml")
+		fmt.Fprint(w, xmlData)
+	}))
+	defer server.Close()
+
+	device := &models.DiscoveredDevice{
+		Host: "127.0.0.1",
+		Name: "Initial Name",
+	}
+
+	service := &Service{}
+	err := service.enrichDeviceInfo(device, server.URL)
+
+	if err != nil {
+		t.Fatalf("enrichDeviceInfo failed: %v", err)
+	}
+
+	if device.Name != "Sound Machinery" {
+		t.Errorf("expected Name 'Sound Machinery', got '%s'", device.Name)
+	}
+
+	if device.ModelID != "SoundTouch 10" {
+		t.Errorf("expected ModelID 'SoundTouch 10', got '%s'", device.ModelID)
+	}
+
+	if device.UPnPSerial != "A81B6A536A09" {
+		t.Errorf("expected UPnPSerial 'A81B6A536A09', got '%s'", device.UPnPSerial)
+	}
+}
+
+func TestUPnP_Unmarshal(t *testing.T) {
+	data := `<?xml version="1.0" encoding="utf-8"?>
+<root xmlns="urn:schemas-upnp-org:device-1-0">
+    <device>
+        <friendlyName>Sound Machinery</friendlyName>
+        <modelName>SoundTouch 10</modelName>
+        <serialNumber>A81B6A536A09</serialNumber>
+    </device>
+</root>`
+
+	var upnpRoot struct {
+		XMLName xml.Name `xml:"root"`
+		Device  struct {
+			FriendlyName string `xml:"friendlyName"`
+			ModelName    string `xml:"modelName"`
+			SerialNumber string `xml:"serialNumber"`
+		} `xml:"device"`
+	}
+
+	err := xml.Unmarshal([]byte(data), &upnpRoot)
+	if err != nil {
+		t.Fatalf("Unmarshal failed: %v", err)
+	}
+
+	if upnpRoot.Device.FriendlyName != "Sound Machinery" {
+		t.Errorf("expected FriendlyName 'Sound Machinery', got '%s'", upnpRoot.Device.FriendlyName)
+	}
+	if upnpRoot.Device.ModelName != "SoundTouch 10" {
+		t.Errorf("expected ModelName 'SoundTouch 10', got '%s'", upnpRoot.Device.ModelName)
+	}
+	if upnpRoot.Device.SerialNumber != "A81B6A536A09" {
+		t.Errorf("expected SerialNumber 'A81B6A536A09', got '%s'", upnpRoot.Device.SerialNumber)
+	}
+}

pkg/models/device.go

@@ -70,6 +70,7 @@ type DiscoveredDevice struct {
 	// Protocol-specific details
 	UPnPLocation string `json:"upnp_location,omitempty"` // UPnP device description XML URL
 	UPnPUSN      string `json:"upnp_usn,omitempty"`      // UPnP Unique Service Name
+	UPnPSerial   string `json:"upnp_serial,omitempty"`   // Serial number from UPnP (MAC address)
 	MDNSHostname string `json:"mdns_hostname,omitempty"` // mDNS hostname (e.g., "device.local.")
 	MDNSService  string `json:"mdns_service,omitempty"`  // mDNS service name
 	ConfigName   string `json:"config_name,omitempty"`   // Original name from config
@@ -94,6 +95,7 @@ func (d *DiscoveredDevice) GetProtocolSpecificData() map[string]interface{} {
 		data["upnp"] = map[string]string{
 			"location": d.UPnPLocation,
 			"usn":      d.UPnPUSN,
+			"serial":   d.UPnPSerial,
 		}
 	}
 

pkg/models/models.go

@@ -184,6 +184,7 @@ type ServiceDeviceInfo struct {
 	FirmwareVersion     string `json:"firmware_version" xml:"softwareVersion"`
 	IPAddress           string `json:"ip_address" xml:"ipAddress"`
 	Name                string `json:"name" xml:"name"`
+	MacAddress          string `json:"mac_address,omitempty" xml:"-"`
 	DiscoveryMethod     string `json:"discovery_method,omitempty"`
 	AccountID           string `json:"account_id,omitempty"`
 }

pkg/service/datastore/datastore.go

@@ -26,6 +26,8 @@ type DataStore struct {
 	DataDir      string
 	eventMutex   sync.RWMutex
 	deviceEvents map[string][]models.DeviceEvent
+	idMutex      sync.RWMutex
+	macToSerial  map[string]string
 }
 
 // NewDataStore creates a new DataStore.
@@ -38,6 +40,7 @@ func NewDataStore(dataDir string) *DataStore {
 	return &DataStore{
 		DataDir:      dataDir,
 		deviceEvents: make(map[string][]models.DeviceEvent),
+		macToSerial:  make(map[string]string),
 	}
 }
 
@@ -53,6 +56,14 @@ func (ds *DataStore) AccountDevicesDir(account string) string {
 
 // AccountDeviceDir returns the directory path for a specific device within an account.
 func (ds *DataStore) AccountDeviceDir(account, device string) string {
+	ds.idMutex.RLock()
+	serial, ok := ds.macToSerial[device]
+	ds.idMutex.RUnlock()
+
+	if ok {
+		device = serial
+	}
+
 	return filepath.Join(ds.AccountDevicesDir(account), device)
 }
 
@@ -77,8 +88,9 @@ func (ds *DataStore) GetDeviceInfo(account, device string) (*models.ServiceDevic
 			SerialNumber    string `xml:"serialNumber"`
 		} `xml:"components>component"`
 		NetworkInfo []struct {
-			Type      string `xml:"type,attr"`
-			IPAddress string `xml:"ipAddress"`
+			Type       string `xml:"type,attr"`
+			IPAddress  string `xml:"ipAddress"`
+			MacAddress string `xml:"macAddress"`
 		} `xml:"networkInfo"`
 	}
 
@@ -105,6 +117,7 @@ func (ds *DataStore) GetDeviceInfo(account, device string) (*models.ServiceDevic
 	for _, net := range info.NetworkInfo {
 		if net.Type == "SCM" {
 			deviceInfo.IPAddress = net.IPAddress
+			deviceInfo.MacAddress = net.MacAddress
 		}
 	}
 
@@ -195,6 +208,10 @@ func (ds *DataStore) listDevicesInAccount(baseDir, accountName string) []models.
 		}
 
 		if err == nil && info != nil {
+			if info.MacAddress != "" && info.DeviceSerialNumber != "" {
+				ds.UpdateMapping(info.MacAddress, info.DeviceSerialNumber)
+			}
+
 			devices = append(devices, *info)
 		}
 	}
@@ -220,8 +237,9 @@ func (ds *DataStore) parseDeviceInfoFile(path string) (*models.ServiceDeviceInfo
 			SerialNumber    string `xml:"serialNumber"`
 		} `xml:"components>component"`
 		NetworkInfo []struct {
-			Type      string `xml:"type,attr"`
-			IPAddress string `xml:"ipAddress"`
+			Type       string `xml:"type,attr"`
+			IPAddress  string `xml:"ipAddress"`
+			MacAddress string `xml:"macAddress"`
 		} `xml:"networkInfo"`
 		DiscoveryMethod string `xml:"discoveryMethod"`
 	}
@@ -250,6 +268,7 @@ func (ds *DataStore) parseDeviceInfoFile(path string) (*models.ServiceDeviceInfo
 	for _, net := range info.NetworkInfo {
 		if net.Type == "SCM" {
 			deviceInfo.IPAddress = net.IPAddress
+			deviceInfo.MacAddress = net.MacAddress
 		}
 	}
 
@@ -633,14 +652,29 @@ func (ds *DataStore) SaveConfiguredSources(account, device string, sources []mod
 	return os.WriteFile(path, append(header, data...), 0644)
 }
 
-// Initialize creates the necessary directory structure for the datastore.
+// UpdateMapping updates the mapping between MAC address and serial number.
+func (ds *DataStore) UpdateMapping(mac, serial string) {
+	if mac == "" || serial == "" {
+		return
+	}
+
+	ds.idMutex.Lock()
+	defer ds.idMutex.Unlock()
+
+	ds.macToSerial[mac] = serial
+}
+
+// Initialize creates the necessary directory structure for the datastore and populates ID mappings.
 func (ds *DataStore) Initialize() error {
 	// Ensure base data directory exists
 	if err := os.MkdirAll(ds.DataDir, 0755); err != nil {
 		return fmt.Errorf("failed to create data directory: %w", err)
 	}
 
-	return nil
+	// Scan for devices to populate MAC to Serial mapping
+	_, err := ds.ListAllDevices()
+
+	return err
 }
 
 // GetETagForPresets returns the ETag (modification time) for the presets file for a specific device.

pkg/service/datastore/mapping_test.go

@@ -0,0 +1,79 @@
+package datastore
+
+import (
+	"os"
+	"path/filepath"
+	"testing"
+
+	"github.com/gesellix/bose-soundtouch/pkg/service/constants"
+)
+
+func TestDataStore_MacAddressMapping(t *testing.T) {
+	if err := os.MkdirAll("testdata/mapping", 0755); err != nil {
+		t.Fatalf("failed to create temp dir: %v", err)
+	}
+	defer os.RemoveAll("testdata/mapping")
+
+	accountID := "12345"
+	serialNumber := "SERIAL123"
+	macAddress := "AABBCCDDEEFF"
+
+	// Create directory structure
+	deviceDir := filepath.Join("testdata/mapping", "accounts", accountID, "devices", serialNumber)
+	if err := os.MkdirAll(deviceDir, 0755); err != nil {
+		t.Fatalf("failed to create device dir: %v", err)
+	}
+
+	// Create DeviceInfo.xml with MAC address
+	deviceInfoXML := `<?xml version="1.0" encoding="UTF-8"?>
+<info deviceID="` + serialNumber + `">
+    <name>Test Device</name>
+    <components>
+        <component>
+            <componentCategory>SCM</componentCategory>
+            <softwareVersion>1.0</softwareVersion>
+            <serialNumber>` + serialNumber + `</serialNumber>
+        </component>
+    </components>
+    <networkInfo type="SCM">
+        <macAddress>` + macAddress + `</macAddress>
+        <ipAddress>192.168.1.10</ipAddress>
+    </networkInfo>
+</info>`
+	if err := os.WriteFile(filepath.Join(deviceDir, constants.DeviceInfoFile), []byte(deviceInfoXML), 0644); err != nil {
+		t.Fatalf("failed to write DeviceInfo.xml: %v", err)
+	}
+
+	// Create Presets.xml so we can verify access
+	presetsXML := `<presets><preset id="1">test</preset></presets>`
+	if err := os.WriteFile(filepath.Join(deviceDir, constants.PresetsFile), []byte(presetsXML), 0644); err != nil {
+		t.Fatalf("failed to write Presets.xml: %v", err)
+	}
+
+	ds := NewDataStore("testdata/mapping")
+	if err := ds.Initialize(); err != nil {
+		t.Fatalf("failed to initialize datastore: %v", err)
+	}
+
+	// Test mapping resolution in AccountDeviceDir
+	resolvedDir := ds.AccountDeviceDir(accountID, macAddress)
+	expectedDir := filepath.Join("testdata/mapping", "accounts", accountID, "devices", serialNumber)
+	if resolvedDir != expectedDir {
+		t.Errorf("expected dir %s, got %s", expectedDir, resolvedDir)
+	}
+
+	// Test that we can still use the serial number directly
+	resolvedDirSerial := ds.AccountDeviceDir(accountID, serialNumber)
+	if resolvedDirSerial != expectedDir {
+		t.Errorf("expected dir %s when using serial, got %s", expectedDir, resolvedDirSerial)
+	}
+
+	// Test GetPresets using MAC address
+	presets, err := ds.GetPresets(accountID, macAddress)
+	if err != nil {
+		t.Errorf("GetPresets failed with MAC address: %v", err)
+	}
+	if len(presets) == 0 {
+		t.Error("expected presets to be loaded")
+	}
+}