Use $HOME/Downloads as default download directory

TODO: Get the default directory properly with XDG

config/config.go

@@ -78,16 +78,15 @@ type Config struct {
 }
 
 // NewConfig creates a config that loads data from the given directory.
-func NewConfig(configDir, cacheDir string) *Config {
+func NewConfig(configDir, cacheDir, downloadDir string) *Config {
-	home, _ := os.UserHomeDir()
 	return &Config{
 		Dir:          configDir,
 		CacheDir:     cacheDir,
+		DownloadDir:  downloadDir,
 		HistoryPath:  filepath.Join(cacheDir, "history.db"),
 		RoomListPath: filepath.Join(cacheDir, "rooms.gob.gz"),
 		StateDir:     filepath.Join(cacheDir, "state"),
 		MediaDir:     filepath.Join(cacheDir, "media"),
-		DownloadDir:  home,
 
 		RoomCacheSize: 32,
 		RoomCacheAge:  1 * 60,

gomuks.go

@@ -38,12 +38,12 @@ type Gomuks struct {
 
 // NewGomuks creates a new Gomuks instance with everything initialized,
 // but does not start it.
-func NewGomuks(uiProvider ifc.UIProvider, configDir, cacheDir string) *Gomuks {
+func NewGomuks(uiProvider ifc.UIProvider, configDir, cacheDir, downloadDir string) *Gomuks {
 	gmx := &Gomuks{
 		stop: make(chan bool, 1),
 	}
 
-	gmx.config = config.NewConfig(configDir, cacheDir)
+	gmx.config = config.NewConfig(configDir, cacheDir, downloadDir)
 	gmx.ui = uiProvider(gmx)
 	gmx.matrix = matrix.NewContainer(gmx)
 

main.go

@@ -58,8 +58,14 @@ func main() {
 		fmt.Fprintln(os.Stderr, "Failed to get cache directory:", err)
 		os.Exit(3)
 	}
+	downloadDir, err := UserDownloadDir()
+	if err != nil {
+		fmt.Fprintln(os.Stderr, "Failed to get download directory:", err)
+		os.Exit(3)
+	}
 
-	gmx := NewGomuks(MainUIProvider, configDir, cacheDir)
+
+	gmx := NewGomuks(MainUIProvider, configDir, cacheDir, downloadDir)
 	gmx.Start()
 
 	// We use os.Exit() everywhere, so exiting by returning from Start() shouldn't happen.
@@ -77,6 +83,11 @@ func UserCacheDir() (dir string, err error) {
 	return
 }
 
+func UserDownloadDir() (dir string, err error) {
+	dir = os.Getenv("HOME")
+	return filepath.Join(dir, "Downloads"), nil
+}
+
 func UserConfigDir() (dir string, err error) {
 	dir = os.Getenv("GOMUKS_CONFIG_HOME")
 	if dir != "" {