fix: banking shell screen rendering artifacts and transfer panic

Fix rendering issues where content from previous screens bled through
when switching between views of different heights/widths:

- Pad every line to full terminal width (ANSI-aware) so shorter lines
  overwrite leftover content from previous renders
- Track terminal height via WindowSizeMsg and pad between content and
  footer to fill the screen
- Send tea.ClearScreen on all screen transitions for height changes
- Fix panic in transfer completion when routing number is < 4 chars

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

internal/shell/banking/banking_test.go

@@ -7,6 +7,7 @@ import (
 	"time"
 
 	tea "github.com/charmbracelet/bubbletea"
+	"github.com/charmbracelet/lipgloss"
 
 	"git.t-juice.club/torjus/oubliette/internal/shell"
 	"git.t-juice.club/torjus/oubliette/internal/storage"
@@ -520,7 +521,7 @@ func TestConfigString(t *testing.T) {
 }
 
 func TestScreenFrame(t *testing.T) {
-	frame := screenFrame("TESTBANK", "TB-0001", "NORTHEAST", "content here")
+	frame := screenFrame("TESTBANK", "TB-0001", "NORTHEAST", "content here", 0)
 	if !strings.Contains(frame, "TESTBANK FEDERAL RESERVE SYSTEM") {
 		t.Error("frame should contain bank name in header")
 	}
@@ -531,3 +532,29 @@ func TestScreenFrame(t *testing.T) {
 		t.Error("frame should contain the content")
 	}
 }
+
+func TestScreenFramePadsLines(t *testing.T) {
+	frame := screenFrame("TESTBANK", "TB-0001", "NE", "short\n", 0)
+	for i, line := range strings.Split(frame, "\n") {
+		w := lipgloss.Width(line)
+		if w > 0 && w < termWidth {
+			t.Errorf("line %d has visual width %d, want at least %d: %q", i, w, termWidth, line)
+		}
+	}
+}
+
+func TestScreenFramePadsToHeight(t *testing.T) {
+	short := screenFrame("TESTBANK", "TB-0001", "NE", "line1\nline2\n", 30)
+	lines := strings.Count(short, "\n")
+	// Total newlines should be at least height-1 (since the last line has no trailing newline).
+	if lines < 29 {
+		t.Errorf("padded frame has %d newlines, want at least 29 for height=30", lines)
+	}
+
+	// Without height, no padding.
+	noPad := screenFrame("TESTBANK", "TB-0001", "NE", "line1\nline2\n", 0)
+	noPadLines := strings.Count(noPad, "\n")
+	if noPadLines >= 29 {
+		t.Errorf("unpadded frame has %d newlines, should be much less than 29", noPadLines)
+	}
+}

internal/shell/banking/model.go

@@ -33,6 +33,7 @@ type model struct {
 	state      *bankState
 	screen     screen
 	quitting   bool
+	height     int
 
 	login      loginModel
 	menu       menuModel
@@ -76,8 +77,12 @@ func (m *model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
 		return m, tea.Quit
 	}
 
-	if keyMsg, ok := msg.(tea.KeyMsg); ok {
+	switch msg := msg.(type) {
-		if keyMsg.Type == tea.KeyCtrlC {
+	case tea.WindowSizeMsg:
+		m.height = msg.Height
+		return m, nil
+	case tea.KeyMsg:
+		if msg.Type == tea.KeyCtrlC {
 			m.quitting = true
 			return m, tea.Quit
 		}
@@ -130,7 +135,7 @@ func (m *model) View() string {
 		content = m.admin.View()
 	}
 
-	return screenFrame(m.bankName, m.terminalID, m.region, content)
+	return screenFrame(m.bankName, m.terminalID, m.region, content, m.height)
 }
 
 // --- Screen update handlers ---
@@ -142,8 +147,8 @@ func (m *model) updateLogin(msg tea.Msg) (tea.Model, tea.Cmd) {
 	if m.login.stage == 2 {
 		// Login always succeeds — this is a honeypot.
 		logCmd := logAction(m.sess, fmt.Sprintf("LOGIN acct=%s", m.login.accountNum), "ACCESS GRANTED")
-		m.goToMenu()
+		clearCmd := m.goToMenu()
-		return m, tea.Batch(cmd, logCmd)
+		return m, tea.Batch(cmd, logCmd, clearCmd)
 	}
 	return m, cmd
 }
@@ -158,36 +163,36 @@ func (m *model) updateMenu(msg tea.Msg) (tea.Model, tea.Cmd) {
 		case "1":
 			m.screen = screenAccountSummary
 			m.summary = newAccountSummaryModel(m.state.Accounts)
-			return m, logAction(m.sess, "MENU 1", "ACCOUNT SUMMARY")
+			return m, tea.Batch(tea.ClearScreen, logAction(m.sess, "MENU 1", "ACCOUNT SUMMARY"))
 		case "2":
 			m.screen = screenAccountDetail
 			m.detail = newAccountDetailModel(m.state.Accounts, m.state.Transactions)
-			return m, logAction(m.sess, "MENU 2", "ACCOUNT DETAIL")
+			return m, tea.Batch(tea.ClearScreen, logAction(m.sess, "MENU 2", "ACCOUNT DETAIL"))
 		case "3":
 			m.screen = screenTransfer
 			m.transfer = newTransferModel()
-			return m, logAction(m.sess, "MENU 3", "WIRE TRANSFER")
+			return m, tea.Batch(tea.ClearScreen, logAction(m.sess, "MENU 3", "WIRE TRANSFER"))
 		case "4":
 			m.screen = screenHistory
 			m.history = newHistoryModel(m.state.Accounts, m.state.Transactions)
-			return m, logAction(m.sess, "MENU 4", "TRANSACTION HISTORY")
+			return m, tea.Batch(tea.ClearScreen, logAction(m.sess, "MENU 4", "TRANSACTION HISTORY"))
 		case "5":
 			m.screen = screenMessages
 			m.messages = newMessagesModel(m.state.Messages)
-			return m, logAction(m.sess, "MENU 5", "SECURE MESSAGES")
+			return m, tea.Batch(tea.ClearScreen, logAction(m.sess, "MENU 5", "SECURE MESSAGES"))
 		case "6":
 			m.screen = screenChangePin
 			m.pinInput = ""
 			m.pinStage = 0
 			m.pinMessage = ""
-			return m, logAction(m.sess, "MENU 6", "CHANGE PIN")
+			return m, tea.Batch(tea.ClearScreen, logAction(m.sess, "MENU 6", "CHANGE PIN"))
 		case "7":
 			m.quitting = true
 			return m, tea.Batch(logAction(m.sess, "LOGOUT", "SESSION ENDED"), tea.Quit)
 		case "99", "admin", "ADMIN":
 			m.screen = screenAdmin
 			m.admin = newAdminModel()
-			return m, logAction(m.sess, "ADMIN ACCESS ATTEMPT", "ADMIN SCREEN SHOWN")
+			return m, tea.Batch(tea.ClearScreen, logAction(m.sess, "ADMIN ACCESS ATTEMPT", "ADMIN SCREEN SHOWN"))
 		}
 		// Invalid choice, reset.
 		m.menu.choice = ""
@@ -197,7 +202,7 @@ func (m *model) updateMenu(msg tea.Msg) (tea.Model, tea.Cmd) {
 
 func (m *model) updateAccountSummary(msg tea.Msg) (tea.Model, tea.Cmd) {
 	if _, ok := msg.(tea.KeyMsg); ok {
-		m.goToMenu()
+		return m, m.goToMenu()
 	}
 	return m, nil
 }
@@ -206,7 +211,7 @@ func (m *model) updateAccountDetail(msg tea.Msg) (tea.Model, tea.Cmd) {
 	var cmd tea.Cmd
 	m.detail, cmd = m.detail.Update(msg)
 	if m.detail.choice == "back" {
-		m.goToMenu()
+		return m, tea.Batch(cmd, m.goToMenu())
 	}
 	return m, cmd
 }
@@ -218,8 +223,14 @@ func (m *model) updateTransfer(msg tea.Msg) (tea.Model, tea.Cmd) {
 
 	// Transfer cancelled.
 	if m.transfer.confirm == "cancelled" {
-		m.goToMenu()
+		clearCmd := m.goToMenu()
-		return m, logAction(m.sess, "WIRE TRANSFER CANCELLED", "USER CANCELLED")
+		return m, tea.Batch(clearCmd, logAction(m.sess, "WIRE TRANSFER CANCELLED", "USER CANCELLED"))
+	}
+
+	// Clear screen when transfer steps change content height significantly
+	// (e.g. confirm→authcode, fields→confirm, authcode→complete).
+	if m.transfer.step != prevStep {
+		cmd = tea.Batch(cmd, tea.ClearScreen)
 	}
 
 	// Transfer completed — log it.
@@ -234,7 +245,7 @@ func (m *model) updateTransfer(msg tea.Msg) (tea.Model, tea.Cmd) {
 	// Completed screen → any key goes back.
 	if m.transfer.step == transferStepComplete {
 		if _, ok := msg.(tea.KeyMsg); ok && prevStep == transferStepComplete {
-			m.goToMenu()
+			return m, tea.Batch(cmd, m.goToMenu())
 		}
 	}
 
@@ -245,7 +256,7 @@ func (m *model) updateHistory(msg tea.Msg) (tea.Model, tea.Cmd) {
 	var cmd tea.Cmd
 	m.history, cmd = m.history.Update(msg)
 	if m.history.choice == "back" {
-		m.goToMenu()
+		return m, tea.Batch(cmd, m.goToMenu())
 	}
 	return m, cmd
 }
@@ -254,8 +265,7 @@ func (m *model) updateMessages(msg tea.Msg) (tea.Model, tea.Cmd) {
 	var cmd tea.Cmd
 	m.messages, cmd = m.messages.Update(msg)
 	if m.messages.choice == "back" {
-		m.goToMenu()
+		return m, tea.Batch(cmd, m.goToMenu())
-		return m, cmd
 	}
 	// Log when viewing a message.
 	if m.messages.viewing >= 0 {
@@ -274,8 +284,7 @@ func (m *model) updateChangePin(msg tea.Msg) (tea.Model, tea.Cmd) {
 	}
 
 	if m.pinStage == 3 {
-		m.goToMenu()
+		return m, m.goToMenu()
-		return m, nil
 	}
 
 	switch keyMsg.Type {
@@ -302,8 +311,7 @@ func (m *model) updateChangePin(msg tea.Msg) (tea.Model, tea.Cmd) {
 			m.pinStage = 1
 		}
 	case tea.KeyEscape:
-		m.goToMenu()
+		return m, m.goToMenu()
-		return m, nil
 	case tea.KeyBackspace:
 		if len(m.pinInput) > 0 {
 			m.pinInput = m.pinInput[:len(m.pinInput)-1]
@@ -367,8 +375,7 @@ func (m *model) updateAdmin(msg tea.Msg) (tea.Model, tea.Cmd) {
 
 	// Check for ESC before delegating.
 	if keyMsg, ok := msg.(tea.KeyMsg); ok && keyMsg.Type == tea.KeyEscape && !m.admin.locked {
-		m.goToMenu()
+		return m, m.goToMenu()
-		return m, nil
 	}
 
 	var cmd tea.Cmd
@@ -383,7 +390,7 @@ func (m *model) updateAdmin(msg tea.Msg) (tea.Model, tea.Cmd) {
 
 	// Log lockout.
 	if m.admin.locked && !prevLocked {
-		cmd = tea.Batch(cmd, logAction(m.sess,
+		cmd = tea.Batch(cmd, tea.ClearScreen, logAction(m.sess,
 			"ADMIN LOCKOUT",
 			"TERMINAL LOCKED - INCIDENT LOGGED"))
 	}
@@ -391,14 +398,14 @@ func (m *model) updateAdmin(msg tea.Msg) (tea.Model, tea.Cmd) {
 	// If locked and any key pressed, go back.
 	if m.admin.locked {
 		if _, ok := msg.(tea.KeyMsg); ok && prevLocked {
-			m.goToMenu()
+			return m, tea.Batch(cmd, m.goToMenu())
 		}
 	}
 
 	return m, cmd
 }
 
-func (m *model) goToMenu() {
+func (m *model) goToMenu() tea.Cmd {
 	unread := 0
 	for _, msg := range m.state.Messages {
 		if msg.Unread {
@@ -407,6 +414,7 @@ func (m *model) goToMenu() {
 	}
 	m.screen = screenMenu
 	m.menu = newMenuModel(m.bankName, unread)
+	return tea.ClearScreen
 }
 
 // logAction returns a tea.Cmd that logs an action to the session store.

internal/shell/banking/screen_transfer.go

@@ -165,8 +165,12 @@ func (m transferModel) View() string {
 		b.WriteString("\n\n")
 		b.WriteString(titleStyle.Render("  TRANSFER QUEUED FOR PROCESSING"))
 		b.WriteString("\n\n")
+		routing := m.transfer.RoutingNumber
+		if len(routing) > 4 {
+			routing = routing[:4]
+		}
 		b.WriteString(baseStyle.Render(fmt.Sprintf("  CONFIRMATION #: WR-%s-%s",
-			m.transfer.RoutingNumber[:4], "847291")))
+			routing, "847291")))
 		b.WriteString("\n")
 		b.WriteString(baseStyle.Render("  STATUS: PENDING FEDWIRE SETTLEMENT"))
 		b.WriteString("\n")

internal/shell/banking/style.go

@@ -100,11 +100,33 @@ func formatCurrency(cents int64) string {
 	return fmt.Sprintf("$%s.%02d", ds, remainder)
 }
 
+// padLine pads a single line (which may contain ANSI codes) to termWidth
+// using its visual width.
+func padLine(line string) string {
+	w := lipgloss.Width(line)
+	if w >= termWidth {
+		return line
+	}
+	return line + strings.Repeat(" ", termWidth-w)
+}
+
+// padLines pads every line in a multi-line string to termWidth so that
+// shorter lines fully overwrite previous content in the terminal.
+func padLines(s string) string {
+	lines := strings.Split(s, "\n")
+	for i, line := range lines {
+		lines[i] = padLine(line)
+	}
+	return strings.Join(lines, "\n")
+}
+
 // screenFrame wraps content in the persistent header and footer.
-func screenFrame(bankName, terminalID, region, content string) string {
+// The height parameter is used to pad the output to fill the terminal,
+// preventing leftover lines from previous renders bleeding through.
+func screenFrame(bankName, terminalID, region, content string, height int) string {
 	var b strings.Builder
 
-	// Header.
+	// Header (4 lines).
 	b.WriteString(divider())
 	b.WriteString("\n")
 	b.WriteString(centerText(bankName + " FEDERAL RESERVE SYSTEM"))
@@ -117,12 +139,29 @@ func screenFrame(bankName, terminalID, region, content string) string {
 	// Content.
 	b.WriteString(content)
 
-	// Footer.
+	// Pad with blank lines between content and footer so the footer
+	// stays at the bottom and the total output fills the terminal height.
+	if height > 0 {
+		const headerLines = 4
+		const footerLines = 2
+		// strings.Count gives newlines; add 1 for the line after the last \n.
+		contentLines := strings.Count(content, "\n") + 1
+		used := headerLines + contentLines + footerLines
+		blankLine := strings.Repeat(" ", termWidth)
+		for i := used; i < height; i++ {
+			b.WriteString(blankLine)
+			b.WriteString("\n")
+		}
+	}
+
+	// Footer (2 lines).
 	b.WriteString("\n")
 	b.WriteString(divider())
 	b.WriteString("\n")
 	footer := fmt.Sprintf(" TERMINAL: %s | REGION: %s | ENCRYPTED SESSION ACTIVE", terminalID, region)
 	b.WriteString(dimStyle.Render(padRight(footer, termWidth)))
 
-	return b.String()
+	// Pad every line to full terminal width so shorter lines overwrite
+	// leftover content from previous renders.
+	return padLines(b.String())
 }