Add headless initial log-in flow

This offloads a lot of intial processing if you're planning on running
gomuks on low-power hardware, but have access to high-power hardware for
the sync (see: large accounts on the beepberry).

A few planned improvements to this mode:
	- Exit gracefully if the transfer directory already exists
	- Make sure key presses are disabled during sync
	- Add verification to flow

gomuks.go

@@ -76,14 +76,14 @@ type Gomuks struct {
 
 // NewGomuks creates a new Gomuks instance with everything initialized,
 // but does not start it.
-func NewGomuks(uiProvider ifc.UIProvider, configDir, dataDir, cacheDir, downloadDir string) *Gomuks {
+func NewGomuks(uiProvider ifc.UIProvider, configDir, dataDir, cacheDir, downloadDir string, isHeadless bool) *Gomuks {
 	gmx := &Gomuks{
 		stop: make(chan bool, 1),
 	}
 
 	gmx.config = config.NewConfig(configDir, dataDir, cacheDir, downloadDir)
 	gmx.ui = uiProvider(gmx)
-	gmx.matrix = matrix.NewContainer(gmx)
+	gmx.matrix = matrix.NewContainer(gmx, isHeadless)
 
 	gmx.config.LoadAll()
 	gmx.ui.Init()
@@ -136,6 +136,24 @@ func (gmx *Gomuks) internalStop(save bool) {
 	if save {
 		gmx.Save()
 	}
+	if gmx.matrix.IsHeadless() {
+		fmt.Println("🚚📦📦 gomuks is ready to go 🚚📦📦")
+		fmt.Println("⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒⇒")
+		fmt.Println()
+		fmt.Println("1.")
+		fmt.Println("copy your new `transfer` folder to the target")
+		fmt.Println("location (perhaps a shiny new beepberry) with")
+		fmt.Println("cp, rsync, or equivalent.")
+		fmt.Println()
+		fmt.Println("2.")
+		fmt.Println("set the GOMUKS_ROOT environment variable to match")
+		fmt.Println("the new location of the directory and edit the")
+		fmt.Println("config file to reflect the changes.")
+		fmt.Println()
+		fmt.Println("recommended reading:")
+		fmt.Println("https://docs.mau.fi/gomuks/faq.html#where-does-gomuks-store-data")
+		fmt.Println("https://beepberry.sqfmi.com")
+	}
 	debug.Print("Exiting process")
 	os.Exit(0)
 }

main.go

@@ -40,12 +40,13 @@ var wantVersion = flag.MakeFull("v", "version", "Show the version of gomuks", "f
 var clearCache = flag.MakeFull("c", "clear-cache", "Clear the cache directory instead of starting", "false").Bool()
 var skipVersionCheck = flag.MakeFull("s", "skip-version-check", "Skip the homeserver version checks at startup and login", "false").Bool()
 var clearData = flag.Make().LongKey("clear-all-data").Usage("Clear all data instead of starting").Default("false").Bool()
+var logInForTransfer = flag.Make().LongKey("log-in-for-transfer").Usage("Log in and generate packaged data for transfer").Default("false").Bool()
 var wantHelp, _ = flag.MakeHelpFlag()
 
 func main() {
 	flag.SetHelpTitles(
 		"gomuks - A terminal Matrix client written in Go.",
-		"gomuks [-vcsh] [--clear-all-data]",
+		"gomuks [-vcsh] [--clear-all-data|--log-in-for-transfer]",
 	)
 	err := flag.Parse()
 	if err != nil {
@@ -58,6 +59,12 @@ func main() {
 		fmt.Println(VersionString)
 		return
 	}
+	if *logInForTransfer {
+		if currentDir, err := os.Getwd(); err == nil {
+			os.Setenv("GOMUKS_ROOT", filepath.Join(currentDir, "transfer"))
+		}
+	}
+
 	debugDir := os.Getenv("DEBUG_DIR")
 	if len(debugDir) > 0 {
 		debug.LogDirectory = debugDir
@@ -103,7 +110,7 @@ func main() {
 	debug.Print("Download directory:", downloadDir)
 
 	matrix.SkipVersionCheck = *skipVersionCheck
-	gmx := NewGomuks(MainUIProvider, configDir, dataDir, cacheDir, downloadDir)
+	gmx := NewGomuks(MainUIProvider, configDir, dataDir, cacheDir, downloadDir, *logInForTransfer)
 
 	if *clearCache {
 		debug.Print("Clearing cache as requested by CLI flag")
@@ -117,6 +124,8 @@ func main() {
 		_ = os.RemoveAll(gmx.config.Dir)
 		fmt.Printf("Cleared cache at %s, data at %s and config at %s\n", gmx.config.CacheDir, gmx.config.DataDir, gmx.config.Dir)
 		return
+	} else if *logInForTransfer {
+		debug.Print("Initializing in headless mode as requested by CLI flag")
 	}
 
 	gmx.Start()

matrix/matrix.go

@@ -60,18 +60,20 @@ type Container struct {
 	ui      ifc.GomuksUI
 	config  *config.Config
 	history *HistoryManager
-	running bool
+	running,
+	headless bool
 	stop chan bool
 
 	typing int64
 }
 
 // NewContainer creates a new Container for the given Gomuks instance.
-func NewContainer(gmx ifc.Gomuks) *Container {
+func NewContainer(gmx ifc.Gomuks, isHeadless bool) *Container {
 	c := &Container{
 		config:   gmx.Config(),
 		ui:       gmx.UI(),
 		gmx:      gmx,
+		headless: isHeadless,
 	}
 
 	return c
@@ -82,6 +84,10 @@ func (c *Container) Client() *mautrix.Client {
 	return c.client
 }
 
+func (c *Container) IsHeadless() bool {
+	return c.headless
+}
+
 type mxLogger struct{}
 
 func (log mxLogger) Debugfln(message string, args ...interface{}) {
@@ -426,6 +432,9 @@ func (c *Container) OnLogin() {
 			c.syncer.Progress.Close()
 			c.syncer.Progress = StubSyncingModal{}
 			c.syncer.FirstDoneCallback = nil
+			if c.headless {
+				c.gmx.Stop(true)
+			}
 		}
 	}
 	c.syncer.InitDoneCallback = func() {
@@ -439,9 +448,11 @@ func (c *Container) OnLogin() {
 		c.config.Rooms.ForceClean()
 		debug.Print("Saving all data")
 		c.config.SaveAll()
+		if !c.headless {
 			debug.Print("Adding rooms to UI")
 			c.ui.MainView().SetRooms(c.config.Rooms)
 			c.ui.Render()
+		}
 		// The initial sync can be a bit heavy, so we force run the GC here
 		// after cleaning up rooms from memory above.
 		debug.Print("Running GC")
@@ -451,7 +462,9 @@ func (c *Container) OnLogin() {
 	c.client.Syncer = c.syncer
 
 	debug.Print("Setting existing rooms")
+	if !c.headless {
 		c.ui.MainView().SetRooms(c.config.Rooms)
+	}
 
 	debug.Print("OnLogin() done.")
 }