pam/adapter: Only draw a model when it's also focused

In the tests that we have we now rely on the fact that when something is
on the screen, then it's also possible to type on it, while this is not
really the case in our bubbletea implementation, because we may end up
drawing and only then we focus a view.

Prevent this, by only showing a model when it's also focused (or ready
to draw), so that there's no risk of showing something and not being
able to get its input.

pam/internal/adapter/authentication.go

@@ -107,6 +107,7 @@ type authenticationComponent interface {
 	Update(msg tea.Msg) (tea.Model, tea.Cmd)
 	View() string
 	Focus() tea.Cmd
+	Focused() bool
 	Blur()
 }
 
@@ -348,11 +349,11 @@ func (m *authenticationModel) Update(msg tea.Msg) (authModel authenticationModel
 
 // Focus focuses this model.
 func (m *authenticationModel) Focus() tea.Cmd {
-	m.focused = true
-
 	if m.currentModel == nil {
 		return nil
 	}
+
+	m.focused = true
 	return m.currentModel.Focus()
 }
 
@@ -419,6 +420,9 @@ func (m authenticationModel) View() string {
 	if m.currentModel == nil {
 		return ""
 	}
+	if !m.Focused() {
+		return ""
+	}
 	contents := []string{m.currentModel.View()}
 
 	errMsg := m.errorMsg

pam/internal/adapter/authmodeselection.go

@@ -220,6 +220,15 @@ func (m authModeSelectionModel) Update(msg tea.Msg) (authModeSelectionModel, tea
 	return m, cmd
 }
 
+// View renders a text view of the authentication UI.
+func (m authModeSelectionModel) View() string {
+	if !m.Focused() {
+		return ""
+	}
+
+	return m.Model.View()
+}
+
 // Focus focuses this model.
 func (m *authModeSelectionModel) Focus() tea.Cmd {
 	m.focused = true

pam/internal/adapter/brokerselection.go

@@ -165,6 +165,15 @@ func (m brokerSelectionModel) Update(msg tea.Msg) (brokerSelectionModel, tea.Cmd
 	return m, cmd
 }
 
+// View renders a text view of the authentication UI.
+func (m brokerSelectionModel) View() string {
+	if !m.Focused() {
+		return ""
+	}
+
+	return m.Model.View()
+}
+
 // Focus focuses this model. It always returns nil.
 func (m *brokerSelectionModel) Focus() tea.Cmd {
 	m.focused = true

pam/internal/adapter/button.go

@@ -54,3 +54,8 @@ func (b *buttonModel) Focus() tea.Cmd {
 func (b *buttonModel) Blur() {
 	b.focused = false
 }
+
+// Focused returns whether if this model is focused.
+func (b buttonModel) Focused() bool {
+	return b.focused
+}

pam/internal/adapter/formmodel.go

@@ -1,6 +1,7 @@
 package adapter
 
 import (
+	"slices"
 	"strings"
 
 	tea "github.com/charmbracelet/bubbletea"
@@ -121,6 +122,10 @@ func (m formModel) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 
 // View renders a text view of the form.
 func (m formModel) View() string {
+	if !m.Focused() {
+		return ""
+	}
+
 	var fields []string
 
 	if m.label != "" {
@@ -151,3 +156,15 @@ func (m formModel) Blur() {
 	}
 	m.focusableModels[m.focusIndex].Blur()
 }
+
+// Focused returns whether if this model is focused.
+func (m formModel) Focused() bool {
+	if len(m.focusableModels) == 0 {
+		// We consider the model being focused in this case, since there's nothing
+		// to interact with, but we want to be able to draw.
+		return true
+	}
+	return slices.ContainsFunc(m.focusableModels, func(ac authenticationComponent) bool {
+		return ac.Focused()
+	})
+}

pam/internal/adapter/newpasswordmodel.go

@@ -1,6 +1,8 @@
 package adapter
 
 import (
+	"slices"
+
 	"github.com/charmbracelet/bubbles/textinput"
 	tea "github.com/charmbracelet/bubbletea"
 	"github.com/charmbracelet/lipgloss"
@@ -180,6 +182,13 @@ func (m newPasswordModel) Blur() {
 	m.focusableModels[m.focusIndex].Blur()
 }
 
+// Focused returns whether if this model is focused.
+func (m newPasswordModel) Focused() bool {
+	return slices.ContainsFunc(m.focusableModels, func(ac authenticationComponent) bool {
+		return ac.Focused()
+	})
+}
+
 func (m *newPasswordModel) focusField(increment int) tea.Cmd {
 	var cmd tea.Cmd
 	focusableLen := len(m.focusableModels)

pam/internal/adapter/qrcodemodel.go

@@ -159,3 +159,9 @@ func (m qrcodeModel) Blur() {
 	}
 	m.buttonModel.Blur()
 }
+
+// Focused returns whether if this model is focused.
+func (m qrcodeModel) Focused() bool {
+	// This is always considered focused.
+	return true
+}

pam/internal/adapter/userselection.go

@@ -164,5 +164,8 @@ func (m userSelectionModel) View() string {
 	if !m.enabled {
 		return ""
 	}
+	if !m.Focused() {
+		return ""
+	}
 	return m.Model.View()
 }