Add initial support for recepient verification

Not staged for the next release due to being blocked by text wrapping bug in Fyne dialogs.

internal/transport/bridge/send.go

@@ -88,6 +88,7 @@ func (p *SendList) OnFileSelect(file fyne.URIReadCloser, err error) {
 
 	go func(i int) {
 		defer func() {
+			p.client.VerifierOk = nil
 			if err = file.Close(); err != nil {
 				fyne.LogError("Error on closing file", err)
 			}
@@ -126,6 +127,10 @@ func (p *SendList) OnDirSelect(dir fyne.ListableURI, err error) {
 	p.NewSendItem(dir.Name(), dir)
 
 	go func(i int) {
+		defer func() {
+			p.client.VerifierOk = nil
+		}()
+
 		code, result, err := p.client.NewDirSend(dir, p.Items[i].Progress.update)
 		if err != nil {
 			fyne.LogError("Error on sending directory", err)
@@ -151,6 +156,10 @@ func (p *SendList) SendText() {
 	p.NewSendItem("Text Snippet", storage.NewFileURI("text")) // The file URI is a hack to get the correct icon
 
 	go func(i int) {
+		defer func() {
+			p.client.VerifierOk = nil
+		}()
+
 		if text := <-p.client.ShowTextSendWindow(); text != "" {
 			code, result, err := p.client.NewTextSend(text, p.Items[i].Progress.update)
 			if err != nil {

internal/transport/receiver.go

@@ -32,6 +32,13 @@ func (c *Client) NewReceive(code string, pathname chan string) (err error) {
 		pathname <- pathToSend
 	}()
 
+	if c.Verify {
+		c.VerifierOk = c.VerifyRecv
+		defer func() {
+			c.VerifierOk = nil
+		}()
+	}
+
 	msg, err := c.Receive(context.Background(), code)
 	if err != nil {
 		fyne.LogError("Error on receiving data", err)

internal/transport/sender.go

@@ -12,11 +12,19 @@ import (
 
 // NewFileSend takes the chosen file and sends it using wormhole-william.
 func (c *Client) NewFileSend(file fyne.URIReadCloser, progress wormhole.SendOption) (string, chan wormhole.SendResult, error) {
+	if c.Verify {
+		c.VerifierOk = c.VerifySend
+	}
+
 	return c.SendFile(context.Background(), file.URI().Name(), file.(io.ReadSeeker), progress)
 }
 
 // NewDirSend takes a listable URI and sends it using wormhole-william.
 func (c *Client) NewDirSend(dir fyne.ListableURI, progress wormhole.SendOption) (string, chan wormhole.SendResult, error) {
+	if c.Verify {
+		c.VerifierOk = c.VerifySend
+	}
+
 	prefixStr, _ := filepath.Split(dir.Path())
 	prefix := len(prefixStr) // Where the prefix ends. Doing it this way is faster and works when paths don't use same separator (\ or /).
 
@@ -47,5 +55,9 @@ func (c *Client) NewDirSend(dir fyne.ListableURI, progress wormhole.SendOption)
 
 // NewTextSend takes a text input and sends the text using wormhole-william.
 func (c *Client) NewTextSend(text string, progress wormhole.SendOption) (string, chan wormhole.SendResult, error) {
+	if c.Verify {
+		c.VerifierOk = c.VerifySend
+	}
+
 	return c.SendText(context.Background(), text, progress)
 }

internal/transport/transport.go

@@ -6,6 +6,7 @@ import (
 	"path/filepath"
 
 	"fyne.io/fyne/v2"
+	"fyne.io/fyne/v2/dialog"
 	"github.com/psanford/wormhole-william/wormhole"
 )
 
@@ -19,6 +20,9 @@ type Client struct {
 	// Notification holds the settings value for if we have notifications enabled or not.
 	Notifications bool
 
+	// Verify holds information about if verification should be enabled or not.
+	Verify bool
+
 	// OverwriteExisting holds the settings value for if we should overwrite already existing files.
 	OverwriteExisting bool
 
@@ -33,6 +37,22 @@ func (c *Client) ShowNotification(title, content string) {
 	}
 }
 
+// VerifySend asks the user to verify that the verification code is correct.
+func (c *Client) VerifySend(input string) bool {
+	verified := make(chan bool)
+	dialog.ShowConfirm("Verify validation", "Is "+input+" the validation code?", func(accept bool) {
+		verified <- accept
+	}, fyne.CurrentApp().Driver().AllWindows()[0])
+
+	return <-verified
+}
+
+// VerifyRecv shows the verification code that should be compared on the other end.
+func (c *Client) VerifyRecv(input string) bool {
+	dialog.ShowInformation("Validation", "Your validation code is: "+input, fyne.CurrentApp().Driver().AllWindows()[0])
+	return true
+}
+
 // NewClient returns a new client for sending and receiving using wormhole-william
 func NewClient() *Client {
 	return &Client{display: createTextWindow()}

internal/ui/settings.go

@@ -31,8 +31,10 @@ type settings struct {
 	overwriteFiles     *widget.RadioGroup
 	notificationRadio  *widget.RadioGroup
 
-	componentSlider     *widget.Slider
-	componentLabel      *widget.Label
+	componentSlider *widget.Slider
+	componentLabel  *widget.Label
+	verifyRadio     *widget.RadioGroup
+
 	appID               *widget.Entry
 	rendezvousURL       *widget.Entry
 	transitRelayAddress *widget.Entry
@@ -83,6 +85,11 @@ func (s *settings) onComponentsChange(value float64) {
 	s.componentLabel.SetText(strconv.Itoa(int(value)))
 }
 
+func (s *settings) onVerifyChanged(selected string) {
+	s.client.Verify = selected == "On"
+	s.app.Preferences().SetString("Verify", selected)
+}
+
 func (s *settings) onAppIDChanged(appID string) {
 	s.client.AppID = appID
 	s.app.Preferences().SetString("AppID", appID)
@@ -113,6 +120,9 @@ func (s *settings) buildUI() *container.Scroll {
 	s.componentSlider, s.componentLabel = &widget.Slider{Min: 2.0, Max: 6.0, Step: 1, OnChanged: s.onComponentsChange}, &widget.Label{}
 	s.componentSlider.SetValue(s.app.Preferences().FloatWithFallback("ComponentLength", 2))
 
+	s.verifyRadio = &widget.RadioGroup{Options: onOffOptions, Horizontal: true, Required: true, OnChanged: s.onVerifyChanged}
+	s.verifyRadio.SetSelected(s.app.Preferences().StringWithFallback("Verify", "Off"))
+
 	s.appID = &widget.Entry{PlaceHolder: wormhole.WormholeCLIAppID, OnChanged: s.onAppIDChanged}
 	s.appID.SetText(s.app.Preferences().String("AppID"))
 
@@ -133,7 +143,10 @@ func (s *settings) buildUI() *container.Scroll {
 	)
 
 	wormholeContainer := container.NewVBox(
-		container.NewGridWithColumns(2, newBoldLabel("Passphrase Length"), container.NewBorder(nil, nil, nil, s.componentLabel, s.componentSlider)),
+		container.NewGridWithColumns(2,
+			newBoldLabel("Passphrase Length"), container.NewBorder(nil, nil, nil, s.componentLabel, s.componentSlider),
+			newBoldLabel("Verify"), s.verifyRadio,
+		),
 		&widget.Accordion{Items: []*widget.AccordionItem{
 			{Title: "Advanced", Detail: container.NewGridWithColumns(2,
 				newBoldLabel("AppID"), s.appID,