feat: add tetris shell (Tetris game TUI)

Full-screen Tetris game using Bubbletea with title screen, ghost piece, lock delay, NES-style scoring, configurable difficulty (easy/normal/hard), and honeypot event logging. Bumps version to 0.17.0. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
2026-02-20 00:59:46 +01:00
parent c9d143d84b
commit 62de222488
10 changed files with 1590 additions and 2 deletions
--- a/README.md
+++ b/README.md
@@ -34,7 +34,7 @@ Key settings:
 - `auth.accept_after` — accept login after N failures per IP (default `10`)
 - `auth.credential_ttl` — how long to remember accepted credentials (default `24h`)
 - `auth.static_credentials` — always-accepted username/password pairs (optional `shell` field routes to a specific shell)
- Available shells: `bash` (fake Linux shell), `fridge` (Samsung Smart Fridge OS), `banking` (80s-style bank terminal TUI), `adventure` (Zork-style text adventure dungeon), `cisco` (Cisco IOS CLI with mode state machine and command abbreviation), `psql` (PostgreSQL psql interactive terminal), `roomba` (iRobot Roomba vacuum robot)
+- Available shells: `bash` (fake Linux shell), `fridge` (Samsung Smart Fridge OS), `banking` (80s-style bank terminal TUI), `adventure` (Zork-style text adventure dungeon), `cisco` (Cisco IOS CLI with mode state machine and command abbreviation), `psql` (PostgreSQL psql interactive terminal), `roomba` (iRobot Roomba vacuum robot), `tetris` (Tetris game TUI)
 - `shell.username_routes` — map usernames to specific shells (e.g. `postgres = "psql"`); credential-specific shell overrides take priority
 - `storage.db_path` — SQLite database path (default `oubliette.db`)
 - `storage.retention_days` — auto-prune records older than N days (default `90`)
--- a/cmd/oubliette/main.go
+++ b/cmd/oubliette/main.go
@@ -20,7 +20,7 @@ import (
 	"git.t-juice.club/torjus/oubliette/internal/web"
 )

-const Version = "0.16.0"
+const Version = "0.17.0"

 func main() {
 	if err := run(); err != nil {
--- a/internal/server/server.go
+++ b/internal/server/server.go
@@ -26,6 +26,7 @@ import (
 	"git.t-juice.club/torjus/oubliette/internal/shell/fridge"
 	psqlshell "git.t-juice.club/torjus/oubliette/internal/shell/psql"
 	"git.t-juice.club/torjus/oubliette/internal/shell/roomba"
+	"git.t-juice.club/torjus/oubliette/internal/shell/tetris"
 	"git.t-juice.club/torjus/oubliette/internal/storage"
 	"golang.org/x/crypto/ssh"
 )
@@ -66,6 +67,9 @@ func New(cfg config.Config, store storage.Store, logger *slog.Logger, m *metrics
 	if err := registry.Register(roomba.NewRoombaShell(), 1); err != nil {
 		return nil, fmt.Errorf("registering roomba shell: %w", err)
 	}
+	if err := registry.Register(tetris.NewTetrisShell(), 1); err != nil {
+		return nil, fmt.Errorf("registering tetris shell: %w", err)
+	}

 	geo, err := geoip.New()
 	if err != nil {
--- a/internal/shell/tetris/data.go
+++ b/internal/shell/tetris/data.go
@@ -0,0 +1,101 @@
+package tetris
+
+import "github.com/charmbracelet/lipgloss"
+
+// pieceType identifies a tetromino (0–6).
+type pieceType int
+
+const (
+	pieceI pieceType = iota
+	pieceO
+	pieceT
+	pieceS
+	pieceZ
+	pieceJ
+	pieceL
+)
+
+const numPieceTypes = 7
+
+// Standard Tetris colors.
+var pieceColors = [numPieceTypes]lipgloss.Color{
+	lipgloss.Color("#00FFFF"), // I — cyan
+	lipgloss.Color("#FFFF00"), // O — yellow
+	lipgloss.Color("#AA00FF"), // T — purple
+	lipgloss.Color("#00FF00"), // S — green
+	lipgloss.Color("#FF0000"), // Z — red
+	lipgloss.Color("#0000FF"), // J — blue
+	lipgloss.Color("#FF8800"), // L — orange
+}
+
+// Each piece has 4 rotations, each rotation is a list of (row, col) offsets
+// relative to the piece origin.
+type rotation [4][2]int
+
+var pieces = [numPieceTypes][4]rotation{
+	// I
+	{
+		{[2]int{0, 0}, [2]int{0, 1}, [2]int{0, 2}, [2]int{0, 3}},
+		{[2]int{0, 0}, [2]int{1, 0}, [2]int{2, 0}, [2]int{3, 0}},
+		{[2]int{0, 0}, [2]int{0, 1}, [2]int{0, 2}, [2]int{0, 3}},
+		{[2]int{0, 0}, [2]int{1, 0}, [2]int{2, 0}, [2]int{3, 0}},
+	},
+	// O
+	{
+		{[2]int{0, 0}, [2]int{0, 1}, [2]int{1, 0}, [2]int{1, 1}},
+		{[2]int{0, 0}, [2]int{0, 1}, [2]int{1, 0}, [2]int{1, 1}},
+		{[2]int{0, 0}, [2]int{0, 1}, [2]int{1, 0}, [2]int{1, 1}},
+		{[2]int{0, 0}, [2]int{0, 1}, [2]int{1, 0}, [2]int{1, 1}},
+	},
+	// T
+	{
+		{[2]int{0, 0}, [2]int{0, 1}, [2]int{0, 2}, [2]int{1, 1}},
+		{[2]int{0, 0}, [2]int{1, 0}, [2]int{2, 0}, [2]int{1, 1}},
+		{[2]int{0, 1}, [2]int{1, 0}, [2]int{1, 1}, [2]int{1, 2}},
+		{[2]int{0, 1}, [2]int{1, 0}, [2]int{1, 1}, [2]int{2, 1}},
+	},
+	// S
+	{
+		{[2]int{0, 1}, [2]int{0, 2}, [2]int{1, 0}, [2]int{1, 1}},
+		{[2]int{0, 0}, [2]int{1, 0}, [2]int{1, 1}, [2]int{2, 1}},
+		{[2]int{0, 1}, [2]int{0, 2}, [2]int{1, 0}, [2]int{1, 1}},
+		{[2]int{0, 0}, [2]int{1, 0}, [2]int{1, 1}, [2]int{2, 1}},
+	},
+	// Z
+	{
+		{[2]int{0, 0}, [2]int{0, 1}, [2]int{1, 1}, [2]int{1, 2}},
+		{[2]int{0, 1}, [2]int{1, 0}, [2]int{1, 1}, [2]int{2, 0}},
+		{[2]int{0, 0}, [2]int{0, 1}, [2]int{1, 1}, [2]int{1, 2}},
+		{[2]int{0, 1}, [2]int{1, 0}, [2]int{1, 1}, [2]int{2, 0}},
+	},
+	// J
+	{
+		{[2]int{0, 0}, [2]int{1, 0}, [2]int{1, 1}, [2]int{1, 2}},
+		{[2]int{0, 0}, [2]int{0, 1}, [2]int{1, 0}, [2]int{2, 0}},
+		{[2]int{0, 0}, [2]int{0, 1}, [2]int{0, 2}, [2]int{1, 2}},
+		{[2]int{0, 0}, [2]int{1, 0}, [2]int{2, 0}, [2]int{2, 1}},
+	},
+	// L
+	{
+		{[2]int{0, 2}, [2]int{1, 0}, [2]int{1, 1}, [2]int{1, 2}},
+		{[2]int{0, 0}, [2]int{1, 0}, [2]int{2, 0}, [2]int{2, 1}},
+		{[2]int{0, 0}, [2]int{0, 1}, [2]int{0, 2}, [2]int{1, 0}},
+		{[2]int{0, 0}, [2]int{0, 1}, [2]int{1, 1}, [2]int{2, 1}},
+	},
+}
+
+// spawnCol returns the starting column for a piece, centering it on the board.
+func spawnCol(pt pieceType, rot int) int {
+	shape := pieces[pt][rot]
+	minC, maxC := shape[0][1], shape[0][1]
+	for _, off := range shape {
+		if off[1] < minC {
+			minC = off[1]
+		}
+		if off[1] > maxC {
+			maxC = off[1]
+		}
+	}
+	width := maxC - minC + 1
+	return (boardCols - width) / 2
+}
--- a/internal/shell/tetris/game.go
+++ b/internal/shell/tetris/game.go
@@ -0,0 +1,210 @@
+package tetris
+
+import "math/rand/v2"
+
+const (
+	boardRows = 20
+	boardCols = 10
+)
+
+// cell represents a single board cell. Zero value is empty.
+type cell struct {
+	filled bool
+	piece  pieceType // which piece type filled this cell (for color)
+}
+
+// gameState holds all mutable state for a Tetris game.
+type gameState struct {
+	board      [boardRows][boardCols]cell
+	current    pieceType
+	currentRot int
+	currentRow int
+	currentCol int
+	next       pieceType
+	score      int
+	level      int
+	lines      int
+	gameOver   bool
+}
+
+// newGame creates a new game state, optionally starting at a given level.
+func newGame(startLevel int) *gameState {
+	g := &gameState{
+		level: startLevel,
+		next:  pieceType(rand.IntN(numPieceTypes)),
+	}
+	g.spawnPiece()
+	return g
+}
+
+// spawnPiece pulls the next piece and generates a new next.
+func (g *gameState) spawnPiece() {
+	g.current = g.next
+	g.next = pieceType(rand.IntN(numPieceTypes))
+	g.currentRot = 0
+	g.currentRow = 0
+	g.currentCol = spawnCol(g.current, 0)
+
+	if !g.canPlace(g.current, g.currentRot, g.currentRow, g.currentCol) {
+		g.gameOver = true
+	}
+}
+
+// canPlace checks whether the piece fits at the given position.
+func (g *gameState) canPlace(pt pieceType, rot, row, col int) bool {
+	shape := pieces[pt][rot]
+	for _, off := range shape {
+		r, c := row+off[0], col+off[1]
+		if r < 0 || r >= boardRows || c < 0 || c >= boardCols {
+			return false
+		}
+		if g.board[r][c].filled {
+			return false
+		}
+	}
+	return true
+}
+
+// moveLeft moves the current piece left if possible.
+func (g *gameState) moveLeft() bool {
+	if g.canPlace(g.current, g.currentRot, g.currentRow, g.currentCol-1) {
+		g.currentCol--
+		return true
+	}
+	return false
+}
+
+// moveRight moves the current piece right if possible.
+func (g *gameState) moveRight() bool {
+	if g.canPlace(g.current, g.currentRot, g.currentRow, g.currentCol+1) {
+		g.currentCol++
+		return true
+	}
+	return false
+}
+
+// moveDown moves the current piece down one row. Returns false if it cannot.
+func (g *gameState) moveDown() bool {
+	if g.canPlace(g.current, g.currentRot, g.currentRow+1, g.currentCol) {
+		g.currentRow++
+		return true
+	}
+	return false
+}
+
+// rotate rotates the current piece clockwise with wall kick attempts.
+func (g *gameState) rotate() bool {
+	newRot := (g.currentRot + 1) % 4
+
+	// Try in-place first.
+	if g.canPlace(g.current, newRot, g.currentRow, g.currentCol) {
+		g.currentRot = newRot
+		return true
+	}
+
+	// Wall kick: try +-1 column offset.
+	for _, offset := range []int{-1, 1} {
+		if g.canPlace(g.current, newRot, g.currentRow, g.currentCol+offset) {
+			g.currentRot = newRot
+			g.currentCol += offset
+			return true
+		}
+	}
+
+	// I piece: try +-2.
+	if g.current == pieceI {
+		for _, offset := range []int{-2, 2} {
+			if g.canPlace(g.current, newRot, g.currentRow, g.currentCol+offset) {
+				g.currentRot = newRot
+				g.currentCol += offset
+				return true
+			}
+		}
+	}
+
+	return false
+}
+
+// ghostRow returns the row where the piece would land.
+func (g *gameState) ghostRow() int {
+	row := g.currentRow
+	for g.canPlace(g.current, g.currentRot, row+1, g.currentCol) {
+		row++
+	}
+	return row
+}
+
+// hardDrop drops the piece to the bottom and returns the number of rows dropped.
+func (g *gameState) hardDrop() int {
+	ghost := g.ghostRow()
+	dropped := ghost - g.currentRow
+	g.currentRow = ghost
+	return dropped
+}
+
+// lockPiece writes the current piece into the board.
+func (g *gameState) lockPiece() {
+	shape := pieces[g.current][g.currentRot]
+	for _, off := range shape {
+		r, c := g.currentRow+off[0], g.currentCol+off[1]
+		if r >= 0 && r < boardRows && c >= 0 && c < boardCols {
+			g.board[r][c] = cell{filled: true, piece: g.current}
+		}
+	}
+}
+
+// clearLines removes completed rows and returns how many were cleared.
+func (g *gameState) clearLines() int {
+	cleared := 0
+	for r := boardRows - 1; r >= 0; r-- {
+		full := true
+		for c := range boardCols {
+			if !g.board[r][c].filled {
+				full = false
+				break
+			}
+		}
+		if full {
+			cleared++
+			// Shift everything above down.
+			for rr := r; rr > 0; rr-- {
+				g.board[rr] = g.board[rr-1]
+			}
+			g.board[0] = [boardCols]cell{}
+			r++ // re-check this row since we shifted
+		}
+	}
+	return cleared
+}
+
+// NES-style scoring multipliers per lines cleared.
+var lineScoreMultipliers = [5]int{0, 40, 100, 300, 1200}
+
+// addScore updates score, lines, and level after clearing rows.
+func (g *gameState) addScore(linesCleared int) {
+	if linesCleared > 0 && linesCleared <= 4 {
+		g.score += lineScoreMultipliers[linesCleared] * (g.level + 1)
+	}
+	g.lines += linesCleared
+
+	// Level up every 10 lines.
+	newLevel := g.lines / 10
+	if newLevel > g.level {
+		g.level = newLevel
+	}
+}
+
+// afterLock locks the piece, clears lines, scores, and spawns the next piece.
+// Returns the number of lines cleared.
+func (g *gameState) afterLock() int {
+	g.lockPiece()
+	cleared := g.clearLines()
+	g.addScore(cleared)
+	g.spawnPiece()
+	return cleared
+}
+
+// tickInterval returns the gravity interval in milliseconds for the current level.
+func tickInterval(level int) int {
+	return max(800-level*60, 100)
+}
--- a/internal/shell/tetris/model.go
+++ b/internal/shell/tetris/model.go
@@ -0,0 +1,331 @@
+package tetris
+
+import (
+	"context"
+	"fmt"
+	"strings"
+	"time"
+
+	tea "github.com/charmbracelet/bubbletea"
+
+	"git.t-juice.club/torjus/oubliette/internal/shell"
+)
+
+type screen int
+
+const (
+	screenTitle screen = iota
+	screenGame
+	screenGameOver
+)
+
+type tickMsg time.Time
+type lockMsg time.Time
+
+const lockDelay = 500 * time.Millisecond
+
+type model struct {
+	sess       *shell.SessionContext
+	difficulty string
+	screen     screen
+	game       *gameState
+	quitting   bool
+	height     int
+	keypresses int
+	locking    bool // true when piece has landed and lock delay is active
+}
+
+func newModel(sess *shell.SessionContext, difficulty string) *model {
+	return &model{
+		sess:       sess,
+		difficulty: difficulty,
+		screen:     screenTitle,
+	}
+}
+
+func (m *model) Init() tea.Cmd {
+	return nil
+}
+
+func (m *model) Update(msg tea.Msg) (tea.Model, tea.Cmd) {
+	if m.quitting {
+		return m, tea.Quit
+	}
+
+	switch msg := msg.(type) {
+	case tea.WindowSizeMsg:
+		m.height = msg.Height
+		return m, nil
+	case tea.KeyMsg:
+		m.keypresses++
+		if msg.Type == tea.KeyCtrlC {
+			m.quitting = true
+			return m, tea.Batch(
+				logAction(m.sess, fmt.Sprintf("QUIT score=%d level=%d lines=%d keys=%d", m.gameScore(), m.gameLevel(), m.gameLines(), m.keypresses), "SESSION ENDED"),
+				tea.Quit,
+			)
+		}
+	}
+
+	switch m.screen {
+	case screenTitle:
+		return m.updateTitle(msg)
+	case screenGame:
+		return m.updateGame(msg)
+	case screenGameOver:
+		return m.updateGameOver(msg)
+	}
+
+	return m, nil
+}
+
+func (m *model) View() string {
+	var content string
+	switch m.screen {
+	case screenTitle:
+		content = m.titleView()
+	case screenGame:
+		content = gameView(m.game)
+	case screenGameOver:
+		content = m.gameOverView()
+	}
+
+	return gameFrame(content, m.height)
+}
+
+// --- Title screen ---
+
+func (m *model) titleView() string {
+	var b strings.Builder
+	b.WriteString("\n")
+	b.WriteString(titleStyle.Render("  ████████╗███████╗████████╗██████╗ ██╗███████╗"))
+	b.WriteString("\n")
+	b.WriteString(titleStyle.Render("  ╚══██╔══╝██╔════╝╚══██╔══╝██╔══██╗██║██╔════╝"))
+	b.WriteString("\n")
+	b.WriteString(titleStyle.Render("     ██║   █████╗     ██║   ██████╔╝██║███████╗"))
+	b.WriteString("\n")
+	b.WriteString(titleStyle.Render("     ██║   ██╔══╝     ██║   ██╔══██╗██║╚════██║"))
+	b.WriteString("\n")
+	b.WriteString(titleStyle.Render("     ██║   ███████╗   ██║   ██║  ██║██║███████║"))
+	b.WriteString("\n")
+	b.WriteString(titleStyle.Render("     ╚═╝   ╚══════╝   ╚═╝   ╚═╝  ╚═╝╚═╝╚══════╝"))
+	b.WriteString("\n\n")
+	b.WriteString(baseStyle.Render("  Press any key to start"))
+	b.WriteString("\n")
+	return b.String()
+}
+
+func (m *model) updateTitle(msg tea.Msg) (tea.Model, tea.Cmd) {
+	if _, ok := msg.(tea.KeyMsg); ok {
+		m.screen = screenGame
+		var startLevel int
+		if m.difficulty == "hard" {
+			startLevel = 5
+		}
+		m.game = newGame(startLevel)
+		return m, tea.Batch(
+			tea.ClearScreen,
+			m.scheduleTick(),
+			logAction(m.sess, "GAME START", fmt.Sprintf("difficulty=%s", m.difficulty)),
+		)
+	}
+	return m, nil
+}
+
+// --- Game screen ---
+
+func (m *model) scheduleTick() tea.Cmd {
+	ms := tickInterval(m.game.level)
+	if m.difficulty == "easy" {
+		ms = max(1000-m.game.level*60, 150)
+	}
+	return tea.Tick(time.Duration(ms)*time.Millisecond, func(t time.Time) tea.Msg {
+		return tickMsg(t)
+	})
+}
+
+func (m *model) scheduleLock() tea.Cmd {
+	return tea.Tick(lockDelay, func(t time.Time) tea.Msg {
+		return lockMsg(t)
+	})
+}
+
+// performLock locks the piece, clears lines, and returns commands for logging
+// and scheduling the next tick. Returns nil if game over (goToGameOver is
+// included in the returned batch).
+func (m *model) performLock() tea.Cmd {
+	m.locking = false
+	cleared := m.game.afterLock()
+	if m.game.gameOver {
+		return tea.Batch(
+			logAction(m.sess, fmt.Sprintf("GAME OVER score=%d level=%d lines=%d keys=%d", m.game.score, m.game.level, m.game.lines, m.keypresses), "GAME OVER"),
+			m.goToGameOver(),
+		)
+	}
+	var cmds []tea.Cmd
+	cmds = append(cmds, m.scheduleTick())
+	if cleared > 0 {
+		cmds = append(cmds, logAction(m.sess, fmt.Sprintf("LINES %d score=%d", cleared, m.game.score), fmt.Sprintf("total=%d", m.game.lines)))
+		prevLevel := (m.game.lines - cleared) / 10
+		if m.game.level > prevLevel {
+			cmds = append(cmds, logAction(m.sess, fmt.Sprintf("LEVEL UP %d", m.game.level), fmt.Sprintf("score=%d", m.game.score)))
+		}
+	}
+	return tea.Batch(cmds...)
+}
+
+func (m *model) updateGame(msg tea.Msg) (tea.Model, tea.Cmd) {
+	switch msg := msg.(type) {
+	case lockMsg:
+		if m.game.gameOver || !m.locking {
+			return m, nil
+		}
+		// Lock delay expired — lock the piece now.
+		return m, m.performLock()
+
+	case tickMsg:
+		if m.game.gameOver || m.locking {
+			return m, nil
+		}
+		if !m.game.moveDown() {
+			// Piece landed — start lock delay instead of locking immediately.
+			m.locking = true
+			return m, m.scheduleLock()
+		}
+		return m, m.scheduleTick()
+
+	case tea.KeyMsg:
+		if m.game.gameOver {
+			return m, nil
+		}
+
+		switch msg.String() {
+		case "left":
+			m.game.moveLeft()
+			// If piece can now drop further, cancel lock delay.
+			if m.locking && m.game.canPlace(m.game.current, m.game.currentRot, m.game.currentRow+1, m.game.currentCol) {
+				m.locking = false
+			}
+		case "right":
+			m.game.moveRight()
+			if m.locking && m.game.canPlace(m.game.current, m.game.currentRot, m.game.currentRow+1, m.game.currentCol) {
+				m.locking = false
+			}
+		case "down":
+			if m.game.moveDown() {
+				m.game.score++ // soft drop bonus
+				if m.locking {
+					m.locking = false
+				}
+			}
+		case "up", "z":
+			m.game.rotate()
+			if m.locking && m.game.canPlace(m.game.current, m.game.currentRot, m.game.currentRow+1, m.game.currentCol) {
+				m.locking = false
+			}
+		case " ":
+			m.locking = false
+			dropped := m.game.hardDrop()
+			m.game.score += dropped * 2
+			return m, m.performLock()
+		case "q":
+			m.quitting = true
+			return m, tea.Batch(
+				logAction(m.sess, fmt.Sprintf("QUIT score=%d level=%d lines=%d keys=%d", m.game.score, m.game.level, m.game.lines, m.keypresses), "PLAYER QUIT"),
+				tea.Quit,
+			)
+		}
+		return m, nil
+	}
+
+	return m, nil
+}
+
+// --- Game over screen ---
+
+func (m *model) goToGameOver() tea.Cmd {
+	m.screen = screenGameOver
+	return tea.ClearScreen
+}
+
+func (m *model) gameOverView() string {
+	var b strings.Builder
+	b.WriteString("\n")
+	b.WriteString(titleStyle.Render("  GAME OVER"))
+	b.WriteString("\n\n")
+	b.WriteString(baseStyle.Render(fmt.Sprintf("  Score: %s", formatScore(m.game.score))))
+	b.WriteString("\n")
+	b.WriteString(baseStyle.Render(fmt.Sprintf("  Level: %d", m.game.level)))
+	b.WriteString("\n")
+	b.WriteString(baseStyle.Render(fmt.Sprintf("  Lines: %d", m.game.lines)))
+	b.WriteString("\n\n")
+	b.WriteString(dimStyle.Render("  R - Play again"))
+	b.WriteString("\n")
+	b.WriteString(dimStyle.Render("  Q - Quit"))
+	b.WriteString("\n")
+	return b.String()
+}
+
+func (m *model) updateGameOver(msg tea.Msg) (tea.Model, tea.Cmd) {
+	if keyMsg, ok := msg.(tea.KeyMsg); ok {
+		switch keyMsg.String() {
+		case "r":
+			startLevel := 0
+			if m.difficulty == "hard" {
+				startLevel = 5
+			}
+			m.game = newGame(startLevel)
+			m.screen = screenGame
+			m.keypresses = 0
+			return m, tea.Batch(
+				tea.ClearScreen,
+				m.scheduleTick(),
+				logAction(m.sess, "RESTART", fmt.Sprintf("difficulty=%s", m.difficulty)),
+			)
+		case "q":
+			m.quitting = true
+			return m, tea.Batch(
+				logAction(m.sess, fmt.Sprintf("QUIT score=%d level=%d lines=%d keys=%d", m.game.score, m.game.level, m.game.lines, m.keypresses), "PLAYER QUIT"),
+				tea.Quit,
+			)
+		}
+	}
+	return m, nil
+}
+
+// Helper methods for safe access when game may be nil.
+func (m *model) gameScore() int {
+	if m.game != nil {
+		return m.game.score
+	}
+	return 0
+}
+
+func (m *model) gameLevel() int {
+	if m.game != nil {
+		return m.game.level
+	}
+	return 0
+}
+
+func (m *model) gameLines() int {
+	if m.game != nil {
+		return m.game.lines
+	}
+	return 0
+}
+
+// logAction returns a tea.Cmd that logs an action to the session store.
+func logAction(sess *shell.SessionContext, input, output string) tea.Cmd {
+	return func() tea.Msg {
+		if sess.Store != nil {
+			ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
+			defer cancel()
+			_ = sess.Store.AppendSessionLog(ctx, sess.SessionID, input, output)
+		}
+		if sess.OnCommand != nil {
+			sess.OnCommand("tetris")
+		}
+		return nil
+	}
+}
--- a/internal/shell/tetris/style.go
+++ b/internal/shell/tetris/style.go
@@ -0,0 +1,286 @@
+package tetris
+
+import (
+	"fmt"
+	"strings"
+
+	"github.com/charmbracelet/lipgloss"
+)
+
+const termWidth = 80
+
+var (
+	colorWhite = lipgloss.Color("#FFFFFF")
+	colorDim   = lipgloss.Color("#555555")
+	colorBlack = lipgloss.Color("#000000")
+	colorGhost = lipgloss.Color("#333333")
+)
+
+var (
+	baseStyle = lipgloss.NewStyle().
+			Foreground(colorWhite).
+			Background(colorBlack)
+
+	dimStyle = lipgloss.NewStyle().
+			Foreground(colorDim).
+			Background(colorBlack)
+
+	titleStyle = lipgloss.NewStyle().
+			Foreground(lipgloss.Color("#00FFFF")).
+			Background(colorBlack).
+			Bold(true)
+
+	sidebarLabelStyle = lipgloss.NewStyle().
+				Foreground(colorDim).
+				Background(colorBlack)
+
+	sidebarValueStyle = lipgloss.NewStyle().
+				Foreground(colorWhite).
+				Background(colorBlack).
+				Bold(true)
+)
+
+// cellStyle returns a style for a filled cell of a given piece type.
+func cellStyle(pt pieceType) lipgloss.Style {
+	return lipgloss.NewStyle().
+		Foreground(pieceColors[pt]).
+		Background(colorBlack)
+}
+
+// ghostStyle returns a dimmed style for the ghost piece.
+func ghostCellStyle() lipgloss.Style {
+	return lipgloss.NewStyle().
+		Foreground(colorGhost).
+		Background(colorBlack)
+}
+
+// renderBoard renders the board, current piece, and ghost piece as a string.
+func renderBoard(g *gameState) string {
+	// Build a display grid that includes the current piece and ghost.
+	type displayCell struct {
+		filled bool
+		ghost  bool
+		piece  pieceType
+	}
+	var grid [boardRows][boardCols]displayCell
+
+	// Copy locked cells.
+	for r := range boardRows {
+		for c := range boardCols {
+			if g.board[r][c].filled {
+				grid[r][c] = displayCell{filled: true, piece: g.board[r][c].piece}
+			}
+		}
+	}
+
+	// Ghost piece.
+	ghostR := g.ghostRow()
+	if ghostR != g.currentRow {
+		shape := pieces[g.current][g.currentRot]
+		for _, off := range shape {
+			r, c := ghostR+off[0], g.currentCol+off[1]
+			if r >= 0 && r < boardRows && c >= 0 && c < boardCols && !grid[r][c].filled {
+				grid[r][c] = displayCell{ghost: true, piece: g.current}
+			}
+		}
+	}
+
+	// Current piece.
+	shape := pieces[g.current][g.currentRot]
+	for _, off := range shape {
+		r, c := g.currentRow+off[0], g.currentCol+off[1]
+		if r >= 0 && r < boardRows && c >= 0 && c < boardCols {
+			grid[r][c] = displayCell{filled: true, piece: g.current}
+		}
+	}
+
+	// Render grid.
+	var b strings.Builder
+	borderStyle := dimStyle
+
+	for _, row := range grid {
+		b.WriteString(borderStyle.Render("|"))
+		for _, dc := range row {
+			switch {
+			case dc.filled:
+				b.WriteString(cellStyle(dc.piece).Render("[]"))
+			case dc.ghost:
+				b.WriteString(ghostCellStyle().Render("::"))
+			default:
+				b.WriteString(baseStyle.Render("  "))
+			}
+		}
+		b.WriteString(borderStyle.Render("|"))
+		b.WriteString("\n")
+	}
+	b.WriteString(borderStyle.Render("+" + strings.Repeat("--", boardCols) + "+"))
+
+	return b.String()
+}
+
+// renderNextPiece renders the "next piece" preview box.
+func renderNextPiece(pt pieceType) string {
+	shape := pieces[pt][0]
+	// Determine bounding box.
+	minR, maxR := shape[0][0], shape[0][0]
+	minC, maxC := shape[0][1], shape[0][1]
+	for _, off := range shape {
+		if off[0] < minR {
+			minR = off[0]
+		}
+		if off[0] > maxR {
+			maxR = off[0]
+		}
+		if off[1] < minC {
+			minC = off[1]
+		}
+		if off[1] > maxC {
+			maxC = off[1]
+		}
+	}
+
+	rows := maxR - minR + 1
+	cols := maxC - minC + 1
+
+	// Build a small grid.
+	grid := make([][]bool, rows)
+	for i := range grid {
+		grid[i] = make([]bool, cols)
+	}
+	for _, off := range shape {
+		grid[off[0]-minR][off[1]-minC] = true
+	}
+
+	var b strings.Builder
+	boxWidth := 8 // chars for the box interior
+	b.WriteString(dimStyle.Render("+" + strings.Repeat("-", boxWidth) + "+"))
+	b.WriteString("\n")
+
+	for r := range rows {
+		b.WriteString(dimStyle.Render("|"))
+		// Center the piece in the box.
+		pieceWidth := cols * 2
+		leftPad := (boxWidth - pieceWidth) / 2
+		rightPad := boxWidth - pieceWidth - leftPad
+		b.WriteString(baseStyle.Render(strings.Repeat(" ", leftPad)))
+		for c := range cols {
+			if grid[r][c] {
+				b.WriteString(cellStyle(pt).Render("[]"))
+			} else {
+				b.WriteString(baseStyle.Render("  "))
+			}
+		}
+		b.WriteString(baseStyle.Render(strings.Repeat(" ", rightPad)))
+		b.WriteString(dimStyle.Render("|"))
+		b.WriteString("\n")
+	}
+
+	// Fill remaining rows in the box (max 4 rows for I piece).
+	for r := rows; r < 2; r++ {
+		b.WriteString(dimStyle.Render("|"))
+		b.WriteString(baseStyle.Render(strings.Repeat(" ", boxWidth)))
+		b.WriteString(dimStyle.Render("|"))
+		b.WriteString("\n")
+	}
+
+	b.WriteString(dimStyle.Render("+" + strings.Repeat("-", boxWidth) + "+"))
+	return b.String()
+}
+
+// formatScore formats a score with comma separators.
+func formatScore(n int) string {
+	s := fmt.Sprintf("%d", n)
+	if len(s) <= 3 {
+		return s
+	}
+	var parts []string
+	for len(s) > 3 {
+		parts = append([]string{s[len(s)-3:]}, parts...)
+		s = s[:len(s)-3]
+	}
+	parts = append([]string{s}, parts...)
+	return strings.Join(parts, ",")
+}
+
+// gameView combines the board and sidebar into the game screen.
+func gameView(g *gameState) string {
+	boardStr := renderBoard(g)
+	boardLines := strings.Split(boardStr, "\n")
+
+	nextStr := renderNextPiece(g.next)
+	nextLines := strings.Split(nextStr, "\n")
+
+	// Build sidebar lines.
+	var sidebar []string
+	sidebar = append(sidebar, sidebarLabelStyle.Render("  NEXT:"))
+	sidebar = append(sidebar, nextLines...)
+	sidebar = append(sidebar, "")
+	sidebar = append(sidebar, sidebarLabelStyle.Render("  SCORE: ")+sidebarValueStyle.Render(formatScore(g.score)))
+	sidebar = append(sidebar, sidebarLabelStyle.Render("  LEVEL: ")+sidebarValueStyle.Render(fmt.Sprintf("%d", g.level)))
+	sidebar = append(sidebar, sidebarLabelStyle.Render("  LINES: ")+sidebarValueStyle.Render(fmt.Sprintf("%d", g.lines)))
+	sidebar = append(sidebar, "")
+	sidebar = append(sidebar, dimStyle.Render("  Controls:"))
+	sidebar = append(sidebar, dimStyle.Render("  <- ->  Move"))
+	sidebar = append(sidebar, dimStyle.Render("  Up/Z   Rotate"))
+	sidebar = append(sidebar, dimStyle.Render("  Down   Soft drop"))
+	sidebar = append(sidebar, dimStyle.Render("  Space  Hard drop"))
+	sidebar = append(sidebar, dimStyle.Render("  Q      Quit"))
+
+	// Combine board and sidebar side by side.
+	var b strings.Builder
+	maxLines := max(len(boardLines), len(sidebar))
+
+	for i := range maxLines {
+		boardLine := ""
+		if i < len(boardLines) {
+			boardLine = boardLines[i]
+		}
+		sidebarLine := ""
+		if i < len(sidebar) {
+			sidebarLine = sidebar[i]
+		}
+
+		// Pad board to fixed width (|  + 10*2 + |  = 22 chars visual).
+		b.WriteString(boardLine)
+		b.WriteString(sidebarLine)
+		b.WriteString("\n")
+	}
+
+	return b.String()
+}
+
+// padLine pads a single line to termWidth.
+func padLine(line string) string {
+	w := lipgloss.Width(line)
+	if w >= termWidth {
+		return line
+	}
+	return line + baseStyle.Render(strings.Repeat(" ", termWidth-w))
+}
+
+// padLines pads every line in a multi-line string to termWidth.
+func padLines(s string) string {
+	lines := strings.Split(s, "\n")
+	for i, line := range lines {
+		lines[i] = padLine(line)
+	}
+	return strings.Join(lines, "\n")
+}
+
+// gameFrame wraps content with padding to fill the terminal.
+func gameFrame(content string, height int) string {
+	var b strings.Builder
+	b.WriteString(content)
+
+	// Pad with blank lines to fill terminal height.
+	if height > 0 {
+		contentLines := strings.Count(content, "\n") + 1
+		blankLine := baseStyle.Render(strings.Repeat(" ", termWidth))
+		for i := contentLines; i < height; i++ {
+			b.WriteString(blankLine)
+			b.WriteString("\n")
+		}
+	}
+
+	return padLines(b.String())
+}
--- a/internal/shell/tetris/tetris.go
+++ b/internal/shell/tetris/tetris.go
@@ -0,0 +1,66 @@
+package tetris
+
+import (
+	"context"
+	"io"
+	"time"
+
+	tea "github.com/charmbracelet/bubbletea"
+
+	"git.t-juice.club/torjus/oubliette/internal/shell"
+)
+
+const sessionTimeout = 10 * time.Minute
+
+// TetrisShell is a Tetris game TUI for the honeypot.
+type TetrisShell struct{}
+
+// NewTetrisShell returns a new TetrisShell instance.
+func NewTetrisShell() *TetrisShell {
+	return &TetrisShell{}
+}
+
+func (t *TetrisShell) Name() string        { return "tetris" }
+func (t *TetrisShell) Description() string { return "Tetris game TUI" }
+
+func (t *TetrisShell) Handle(ctx context.Context, sess *shell.SessionContext, rw io.ReadWriteCloser) error {
+	ctx, cancel := context.WithTimeout(ctx, sessionTimeout)
+	defer cancel()
+
+	difficulty := configString(sess.ShellConfig, "difficulty", "normal")
+
+	m := newModel(sess, difficulty)
+	p := tea.NewProgram(m,
+		tea.WithInput(rw),
+		tea.WithOutput(rw),
+		tea.WithAltScreen(),
+	)
+
+	done := make(chan error, 1)
+	go func() {
+		_, err := p.Run()
+		done <- err
+	}()
+
+	select {
+	case err := <-done:
+		return err
+	case <-ctx.Done():
+		p.Quit()
+		<-done
+		return nil
+	}
+}
+
+// configString reads a string from the shell config map with a default.
+func configString(cfg map[string]any, key, defaultVal string) string {
+	if cfg == nil {
+		return defaultVal
+	}
+	if v, ok := cfg[key]; ok {
+		if s, ok := v.(string); ok && s != "" {
+			return s
+		}
+	}
+	return defaultVal
+}
--- a/internal/shell/tetris/tetris_test.go
+++ b/internal/shell/tetris/tetris_test.go
@@ -0,0 +1,582 @@
+package tetris
+
+import (
+	"context"
+	"strings"
+	"testing"
+	"time"
+
+	tea "github.com/charmbracelet/bubbletea"
+
+	"git.t-juice.club/torjus/oubliette/internal/shell"
+	"git.t-juice.club/torjus/oubliette/internal/storage"
+)
+
+// newTestModel creates a model with a test session context.
+func newTestModel(t *testing.T) (*model, *storage.MemoryStore) {
+	t.Helper()
+	store := storage.NewMemoryStore()
+	sessID, _ := store.CreateSession(context.Background(), "127.0.0.1", "player", "tetris", "")
+	sess := &shell.SessionContext{
+		SessionID: sessID,
+		Username:  "player",
+		Store:     store,
+	}
+	m := newModel(sess, "normal")
+	return m, store
+}
+
+// sendKey sends a single key message to the model and returns the command.
+func sendKey(m *model, key string) tea.Cmd {
+	var msg tea.KeyMsg
+	switch key {
+	case "enter":
+		msg = tea.KeyMsg{Type: tea.KeyEnter}
+	case "up":
+		msg = tea.KeyMsg{Type: tea.KeyUp}
+	case "down":
+		msg = tea.KeyMsg{Type: tea.KeyDown}
+	case "left":
+		msg = tea.KeyMsg{Type: tea.KeyLeft}
+	case "right":
+		msg = tea.KeyMsg{Type: tea.KeyRight}
+	case "space":
+		msg = tea.KeyMsg{Type: tea.KeySpace}
+	case "ctrl+c":
+		msg = tea.KeyMsg{Type: tea.KeyCtrlC}
+	default:
+		if len(key) == 1 {
+			msg = tea.KeyMsg{Type: tea.KeyRunes, Runes: []rune(key)}
+		}
+	}
+	_, cmd := m.Update(msg)
+	return cmd
+}
+
+// sendTick sends a tick message to the model.
+func sendTick(m *model) tea.Cmd {
+	_, cmd := m.Update(tickMsg(time.Now()))
+	return cmd
+}
+
+// execCmds recursively executes tea.Cmd functions (including batches).
+func execCmds(cmd tea.Cmd) {
+	if cmd == nil {
+		return
+	}
+	msg := cmd()
+	if batch, ok := msg.(tea.BatchMsg); ok {
+		for _, c := range batch {
+			execCmds(c)
+		}
+	}
+}
+
+func TestTetrisShellName(t *testing.T) {
+	sh := NewTetrisShell()
+	if sh.Name() != "tetris" {
+		t.Errorf("Name() = %q, want %q", sh.Name(), "tetris")
+	}
+	if sh.Description() == "" {
+		t.Error("Description() should not be empty")
+	}
+}
+
+func TestConfigString(t *testing.T) {
+	cfg := map[string]any{
+		"difficulty": "hard",
+	}
+	if got := configString(cfg, "difficulty", "normal"); got != "hard" {
+		t.Errorf("configString() = %q, want %q", got, "hard")
+	}
+	if got := configString(cfg, "missing", "normal"); got != "normal" {
+		t.Errorf("configString() = %q, want %q", got, "normal")
+	}
+	if got := configString(nil, "difficulty", "normal"); got != "normal" {
+		t.Errorf("configString(nil) = %q, want %q", got, "normal")
+	}
+}
+
+func TestTitleScreenRenders(t *testing.T) {
+	m, _ := newTestModel(t)
+	view := m.View()
+	if !strings.Contains(view, "████") {
+		t.Error("title screen should show TETRIS logo")
+	}
+	if !strings.Contains(view, "Press any key") {
+		t.Error("title screen should show 'Press any key'")
+	}
+}
+
+func TestTitleToGame(t *testing.T) {
+	m, _ := newTestModel(t)
+	if m.screen != screenTitle {
+		t.Fatalf("expected screenTitle, got %d", m.screen)
+	}
+
+	sendKey(m, "enter")
+	if m.screen != screenGame {
+		t.Errorf("expected screenGame after keypress, got %d", m.screen)
+	}
+	if m.game == nil {
+		t.Fatal("game should be initialized")
+	}
+}
+
+func TestGameRenders(t *testing.T) {
+	m, _ := newTestModel(t)
+	sendKey(m, "enter") // start game
+
+	view := m.View()
+	if !strings.Contains(view, "|") {
+		t.Error("game view should contain board borders")
+	}
+	if !strings.Contains(view, "SCORE") {
+		t.Error("game view should show SCORE")
+	}
+	if !strings.Contains(view, "LEVEL") {
+		t.Error("game view should show LEVEL")
+	}
+	if !strings.Contains(view, "LINES") {
+		t.Error("game view should show LINES")
+	}
+	if !strings.Contains(view, "NEXT") {
+		t.Error("game view should show NEXT")
+	}
+}
+
+// --- Pure game logic tests ---
+
+func TestNewGame(t *testing.T) {
+	g := newGame(0)
+	if g.gameOver {
+		t.Error("new game should not be game over")
+	}
+	if g.score != 0 {
+		t.Errorf("initial score = %d, want 0", g.score)
+	}
+	if g.level != 0 {
+		t.Errorf("initial level = %d, want 0", g.level)
+	}
+	if g.lines != 0 {
+		t.Errorf("initial lines = %d, want 0", g.lines)
+	}
+}
+
+func TestNewGameHardLevel(t *testing.T) {
+	g := newGame(5)
+	if g.level != 5 {
+		t.Errorf("hard start level = %d, want 5", g.level)
+	}
+}
+
+func TestMoveLeft(t *testing.T) {
+	g := newGame(0)
+	startCol := g.currentCol
+	g.moveLeft()
+	if g.currentCol != startCol-1 {
+		t.Errorf("after moveLeft: col = %d, want %d", g.currentCol, startCol-1)
+	}
+}
+
+func TestMoveRight(t *testing.T) {
+	g := newGame(0)
+	startCol := g.currentCol
+	g.moveRight()
+	if g.currentCol != startCol+1 {
+		t.Errorf("after moveRight: col = %d, want %d", g.currentCol, startCol+1)
+	}
+}
+
+func TestMoveDown(t *testing.T) {
+	g := newGame(0)
+	startRow := g.currentRow
+	moved := g.moveDown()
+	if !moved {
+		t.Error("moveDown should succeed from starting position")
+	}
+	if g.currentRow != startRow+1 {
+		t.Errorf("after moveDown: row = %d, want %d", g.currentRow, startRow+1)
+	}
+}
+
+func TestCannotMoveLeftBeyondWall(t *testing.T) {
+	g := newGame(0)
+	// Move all the way left.
+	for range boardCols {
+		g.moveLeft()
+	}
+	col := g.currentCol
+	g.moveLeft() // should not move further
+	if g.currentCol != col {
+		t.Errorf("should not move past left wall: col = %d, was %d", g.currentCol, col)
+	}
+}
+
+func TestCannotMoveRightBeyondWall(t *testing.T) {
+	g := newGame(0)
+	// Move all the way right.
+	for range boardCols {
+		g.moveRight()
+	}
+	col := g.currentCol
+	g.moveRight() // should not move further
+	if g.currentCol != col {
+		t.Errorf("should not move past right wall: col = %d, was %d", g.currentCol, col)
+	}
+}
+
+func TestRotate(t *testing.T) {
+	g := newGame(0)
+	startRot := g.currentRot
+	g.rotate()
+	// Rotation should change (possibly with wall kick).
+	if g.currentRot == startRot {
+		// Rotation might legitimately fail in some edge cases, so just check
+		// that the game state is valid.
+		if !g.canPlace(g.current, g.currentRot, g.currentRow, g.currentCol) {
+			t.Error("piece should be in a valid position after rotate attempt")
+		}
+	}
+}
+
+func TestHardDrop(t *testing.T) {
+	g := newGame(0)
+	startRow := g.currentRow
+	dropped := g.hardDrop()
+	if dropped == 0 {
+		t.Error("hard drop should move piece down at least some rows from top")
+	}
+	if g.currentRow <= startRow {
+		t.Errorf("after hardDrop: row = %d should be > %d", g.currentRow, startRow)
+	}
+}
+
+func TestGhostRow(t *testing.T) {
+	g := newGame(0)
+	ghost := g.ghostRow()
+	if ghost < g.currentRow {
+		t.Errorf("ghost row %d should be >= current row %d", ghost, g.currentRow)
+	}
+	// Ghost should be at a position where moving down one more is impossible.
+	if g.canPlace(g.current, g.currentRot, ghost+1, g.currentCol) {
+		t.Error("ghost row should be the lowest valid position")
+	}
+}
+
+func TestLockPiece(t *testing.T) {
+	g := newGame(0)
+	g.hardDrop()
+	pt := g.current
+	row, col, rot := g.currentRow, g.currentCol, g.currentRot
+	g.lockPiece()
+
+	// Verify that the piece's cells are now filled.
+	shape := pieces[pt][rot]
+	for _, off := range shape {
+		r, c := row+off[0], col+off[1]
+		if !g.board[r][c].filled {
+			t.Errorf("cell (%d, %d) should be filled after lockPiece", r, c)
+		}
+	}
+}
+
+func TestClearLines(t *testing.T) {
+	g := newGame(0)
+	// Fill the bottom row completely.
+	for c := range boardCols {
+		g.board[boardRows-1][c] = cell{filled: true, piece: pieceI}
+	}
+	cleared := g.clearLines()
+	if cleared != 1 {
+		t.Errorf("clearLines() = %d, want 1", cleared)
+	}
+	// Bottom row should now be empty (shifted from above).
+	for c := range boardCols {
+		if g.board[boardRows-1][c].filled {
+			t.Errorf("bottom row col %d should be empty after clearing", c)
+		}
+	}
+}
+
+func TestClearMultipleLines(t *testing.T) {
+	g := newGame(0)
+	// Fill the bottom 4 rows.
+	for r := boardRows - 4; r < boardRows; r++ {
+		for c := range boardCols {
+			g.board[r][c] = cell{filled: true, piece: pieceI}
+		}
+	}
+	cleared := g.clearLines()
+	if cleared != 4 {
+		t.Errorf("clearLines() = %d, want 4", cleared)
+	}
+}
+
+func TestScoring(t *testing.T) {
+	tests := []struct {
+		lines int
+		level int
+		want  int
+	}{
+		{1, 0, 40},
+		{2, 0, 100},
+		{3, 0, 300},
+		{4, 0, 1200},
+		{1, 1, 80},
+		{4, 2, 3600},
+	}
+	for _, tt := range tests {
+		g := newGame(tt.level)
+		g.addScore(tt.lines)
+		if g.score != tt.want {
+			t.Errorf("score for %d lines at level %d = %d, want %d", tt.lines, tt.level, g.score, tt.want)
+		}
+	}
+}
+
+func TestLevelUp(t *testing.T) {
+	g := newGame(0)
+	g.lines = 9
+	g.addScore(1) // This should push lines to 10, triggering level 1.
+	if g.level != 1 {
+		t.Errorf("level = %d, want 1 after 10 lines", g.level)
+	}
+}
+
+func TestTickInterval(t *testing.T) {
+	if got := tickInterval(0); got != 800 {
+		t.Errorf("tickInterval(0) = %d, want 800", got)
+	}
+	if got := tickInterval(5); got != 500 {
+		t.Errorf("tickInterval(5) = %d, want 500", got)
+	}
+	// Floor at 100ms.
+	if got := tickInterval(20); got != 100 {
+		t.Errorf("tickInterval(20) = %d, want 100", got)
+	}
+}
+
+func TestFormatScore(t *testing.T) {
+	tests := []struct {
+		n    int
+		want string
+	}{
+		{0, "0"},
+		{100, "100"},
+		{1250, "1,250"},
+		{1000000, "1,000,000"},
+	}
+	for _, tt := range tests {
+		if got := formatScore(tt.n); got != tt.want {
+			t.Errorf("formatScore(%d) = %q, want %q", tt.n, got, tt.want)
+		}
+	}
+}
+
+func TestGameOverScreen(t *testing.T) {
+	m, _ := newTestModel(t)
+	sendKey(m, "enter") // start game
+
+	// Force game over.
+	m.game.gameOver = true
+	m.screen = screenGameOver
+
+	view := m.View()
+	if !strings.Contains(view, "GAME OVER") {
+		t.Error("game over screen should show GAME OVER")
+	}
+	if !strings.Contains(view, "Score") {
+		t.Error("game over screen should show score")
+	}
+}
+
+func TestRestartFromGameOver(t *testing.T) {
+	m, _ := newTestModel(t)
+	sendKey(m, "enter") // start game
+
+	m.game.gameOver = true
+	m.screen = screenGameOver
+
+	sendKey(m, "r")
+	if m.screen != screenGame {
+		t.Errorf("expected screenGame after restart, got %d", m.screen)
+	}
+	if m.game.gameOver {
+		t.Error("game should not be over after restart")
+	}
+}
+
+func TestQuitFromGame(t *testing.T) {
+	m, _ := newTestModel(t)
+	sendKey(m, "enter") // start game
+	sendKey(m, "q")
+	if !m.quitting {
+		t.Error("should be quitting after pressing q")
+	}
+}
+
+func TestQuitFromGameOver(t *testing.T) {
+	m, _ := newTestModel(t)
+	sendKey(m, "enter") // start game
+	m.game.gameOver = true
+	m.screen = screenGameOver
+
+	sendKey(m, "q")
+	if !m.quitting {
+		t.Error("should be quitting after pressing q in game over")
+	}
+}
+
+func TestSoftDropScoring(t *testing.T) {
+	m, _ := newTestModel(t)
+	sendKey(m, "enter") // start game
+
+	scoreBefore := m.game.score
+	sendKey(m, "down")
+	if m.game.score != scoreBefore+1 {
+		t.Errorf("score after soft drop = %d, want %d", m.game.score, scoreBefore+1)
+	}
+}
+
+func TestHardDropScoring(t *testing.T) {
+	m, _ := newTestModel(t)
+	sendKey(m, "enter") // start game
+
+	// Hard drop gives 2 points per row dropped.
+	sendKey(m, "space")
+	if m.game.score < 2 {
+		t.Errorf("score after hard drop = %d, should be at least 2", m.game.score)
+	}
+}
+
+func TestTickMovesDown(t *testing.T) {
+	m, _ := newTestModel(t)
+	sendKey(m, "enter") // start game
+
+	rowBefore := m.game.currentRow
+	sendTick(m)
+	// Piece should either move down by 1, or lock and spawn a new piece at top.
+	movedDown := m.game.currentRow == rowBefore+1
+	respawned := m.game.currentRow < rowBefore
+	if !movedDown && !respawned && !m.game.gameOver {
+		t.Errorf("tick should move piece down or lock+respawn: row was %d, now %d", rowBefore, m.game.currentRow)
+	}
+}
+
+func TestSessionLogs(t *testing.T) {
+	m, store := newTestModel(t)
+
+	// Press key to start game — returns a logAction cmd.
+	cmd := sendKey(m, "enter")
+	if cmd != nil {
+		execCmds(cmd)
+	}
+	time.Sleep(50 * time.Millisecond)
+
+	found := false
+	for _, log := range store.SessionLogs {
+		if strings.Contains(log.Input, "GAME START") {
+			found = true
+			break
+		}
+	}
+	if !found {
+		t.Error("expected GAME START in session logs")
+	}
+}
+
+func TestKeypressCounter(t *testing.T) {
+	m, _ := newTestModel(t)
+	sendKey(m, "enter") // start game
+	sendKey(m, "left")
+	sendKey(m, "right")
+	sendKey(m, "down")
+
+	if m.keypresses != 4 { // enter + 3 game keys
+		t.Errorf("keypresses = %d, want 4", m.keypresses)
+	}
+}
+
+func TestLockDelay(t *testing.T) {
+	m, _ := newTestModel(t)
+	sendKey(m, "enter") // start game
+
+	// Drop piece to the bottom via ticks until it can't move down.
+	for range boardRows + 5 {
+		if m.locking {
+			break
+		}
+		sendTick(m)
+	}
+
+	if !m.locking {
+		t.Fatal("piece should be in locking state after hitting bottom")
+	}
+
+	// During lock delay, we should still be able to move left/right.
+	colBefore := m.game.currentCol
+	sendKey(m, "left")
+	if m.game.currentCol >= colBefore {
+		// Might not have moved if against wall, try right.
+		sendKey(m, "right")
+	}
+
+	// Sending a lockMsg should finalize the piece.
+	m.Update(lockMsg(time.Now()))
+	// After lock, a new piece should have spawned (row near top).
+	if m.game.currentRow > 1 && !m.game.gameOver {
+		t.Errorf("after lock delay, new piece should spawn near top, got row %d", m.game.currentRow)
+	}
+}
+
+func TestLockDelayCancelledByDrop(t *testing.T) {
+	m, _ := newTestModel(t)
+	sendKey(m, "enter") // start game
+
+	// Build a ledge: fill rows 18-19 but leave column 0 empty.
+	for r := boardRows - 2; r < boardRows; r++ {
+		for c := 1; c < boardCols; c++ {
+			m.game.board[r][c] = cell{filled: true, piece: pieceI}
+		}
+	}
+
+	// Move piece to column 0 area and drop it onto the ledge.
+	for range boardCols {
+		m.game.moveLeft()
+	}
+	// Tick down until locking.
+	for range boardRows + 5 {
+		if m.locking {
+			break
+		}
+		sendTick(m)
+	}
+
+	// If piece is on the ledge and we slide it to col 0 (open column),
+	// the lock delay should cancel since it can fall further.
+	// This test just validates the locking flag logic works.
+	if m.locking {
+		// Try moving — if piece can drop further, locking should cancel.
+		sendKey(m, "left")
+		// Whether locking cancels depends on the board state; just verify no crash.
+	}
+}
+
+func TestSpawnCol(t *testing.T) {
+	// All pieces should spawn roughly centered.
+	for pt := range pieceType(numPieceTypes) {
+		col := spawnCol(pt, 0)
+		if col < 0 || col > boardCols-1 {
+			t.Errorf("spawnCol(%d, 0) = %d, out of range", pt, col)
+		}
+		// Verify piece fits at spawn position.
+		shape := pieces[pt][0]
+		for _, off := range shape {
+			c := col + off[1]
+			if c < 0 || c >= boardCols {
+				t.Errorf("piece %d overflows board at spawn: col+offset = %d", pt, c)
+			}
+		}
+	}
+}
--- a/oubliette.toml.example
+++ b/oubliette.toml.example
@@ -39,6 +39,11 @@ password = "admin"
 # password = "roomba"
 # shell = "roomba"

+# [[auth.static_credentials]]
+# username = "player"
+# password = "tetris"
+# shell = "tetris"
+
 [storage]
 db_path = "oubliette.db"
 retention_days = 90
@@ -83,6 +88,9 @@ hostname = "ubuntu-server"
 # [shell.roomba]
 # No configuration options currently.

+# [shell.tetris]
+# difficulty = "normal"  # "easy" (slower start), "normal" (standard), "hard" (start at level 5)
+
 # [detection]
 # enabled = true
 # threshold = 0.6          # 0.0–1.0, sessions above this trigger notifications