Katan: mark build-menu label lambda @Composable

Co-Authored-By: Claude Sonnet 5.5 <[email protected]>
Claude-Session: https://claude.ai/code/session_018njn2eMPAYqAoE49hGRg2X

app/src/main/java/org/prolibertate/games/game/catan/CatanModel.kt

@@ -12,6 +12,11 @@ const val LONGEST_ROAD_MIN = 5
 /** Knights required to take Largest Army. */
 const val LARGEST_ARMY_MIN = 3
 
+/** Pieces each player has: a player who has laid them all cannot build another. */
+const val MAX_ROADS = 15
+const val MAX_SETTLEMENTS = 5
+const val MAX_CITIES = 4
+
 /** Resource cards of each type the bank starts with. */
 const val BANK_PER_RESOURCE = 19
 

app/src/main/java/org/prolibertate/games/game/catan/CatanRules.kt

@@ -272,11 +272,18 @@ object CatanRules : GameRules<CatanState, CatanMove> {
         return takes
     }
 
-    /** Road placements that connect to [seat]'s network, cost aside. */
+    /**
+     * Road placements that connect to [seat]'s network, cost aside. A player
+     * with all fifteen roads laid has none.
+     */
     private fun roadMoves(state: CatanState, seat: Int): List<BuildRoad> =
+        if (state.roads.count { it == seat } >= MAX_ROADS) {
+            emptyList()
+        } else {
             (0 until CatanBoard.EDGE_COUNT)
                 .filter { state.roads[it] == NO_PLAYER && roadConnects(state, seat, it) }
                 .map { BuildRoad(it) }
+        }
 
     /**
      * Settlement placements: an open vertex at least two edges from every
@@ -285,15 +292,27 @@ object CatanRules : GameRules<CatanState, CatanMove> {
      * own move.)
      */
     private fun settlementVertices(state: CatanState, seat: Int): List<Int> =
+        if (piecesOf(state, seat, BuildingType.SETTLEMENT) >= MAX_SETTLEMENTS) {
+            emptyList()
+        } else {
             (0 until CatanBoard.VERTEX_COUNT).filter { v ->
                 vertexOpenForSettlement(state, v) &&
                     CatanBoard.VERTEX_EDGES[v].any { state.roads[it] == seat }
             }
+        }
 
     private fun cityVertices(state: CatanState, seat: Int): List<Int> =
+        if (piecesOf(state, seat, BuildingType.CITY) >= MAX_CITIES) {
+            emptyList()
+        } else {
             (0 until CatanBoard.VERTEX_COUNT).filter { v ->
                 state.buildings[v] == CatanBuilding(BuildingType.SETTLEMENT, seat)
             }
+        }
+
+    /** How many settlements or cities [seat] currently has standing. */
+    private fun piecesOf(state: CatanState, seat: Int, type: BuildingType): Int =
+        state.buildings.count { it?.owner == seat && it.type == type }
 
     private fun tradeResponses(state: CatanState, seat: Int): List<CatanMove> {
         val offer = state.pendingTrade ?: return emptyList()
@@ -310,13 +329,25 @@ object CatanRules : GameRules<CatanState, CatanMove> {
         state.buildings[v] == null &&
             CatanBoard.VERTEX_NEIGHBORS[v].all { state.buildings[it] == null }
 
-    /** A road on [edge] would join [seat]'s network of roads and buildings. */
+    /**
+     * A road on [edge] would join [seat]'s network of roads and buildings.
+     *
+     * It must start from a crossing the network actually reaches. An opponent's
+     * settlement or city on a crossing breaks the network there: roads on either
+     * side of it do not join, so a road cannot be laid *past* it, even with one
+     * of your own roads ending at the same crossing.
+     */
     private fun roadConnects(state: CatanState, seat: Int, edge: Int): Boolean {
         val (a, b) = CatanBoard.EDGE_VERTICES[edge]
-        return CatanBoard.VERTEX_EDGES[a].any { state.roads[it] == seat } ||
+        return networkReaches(state, seat, a) || networkReaches(state, seat, b)
-            CatanBoard.VERTEX_EDGES[b].any { state.roads[it] == seat } ||
+    }
-            state.buildings[a]?.owner == seat ||
+
-            state.buildings[b]?.owner == seat
+    /** Whether [seat]'s roads and buildings reach [vertex] so a road may start there. */
+    private fun networkReaches(state: CatanState, seat: Int, vertex: Int): Boolean {
+        val building = state.buildings[vertex]
+        // Your own building is always a way in; anyone else's is a wall.
+        if (building != null) return building.owner == seat
+        return CatanBoard.VERTEX_EDGES[vertex].any { state.roads[it] == seat }
     }
 
     private fun offerLegal(state: CatanState, seat: Int, move: OfferTrade): Boolean {

app/src/main/java/org/prolibertate/games/ui/game/catan/CatanBoardView.kt

@@ -11,6 +11,7 @@ import androidx.compose.runtime.rememberUpdatedState
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.geometry.Offset
+import androidx.compose.ui.geometry.Size
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.graphics.Path
 import androidx.compose.ui.graphics.StrokeCap
@@ -30,6 +31,7 @@ import org.prolibertate.games.game.catan.BuildingType
 import org.prolibertate.games.game.catan.CatanBoard
 import org.prolibertate.games.game.catan.CatanState
 import org.prolibertate.games.game.catan.NO_PLAYER
+import org.prolibertate.games.game.catan.Resource
 
 /**
  * The island, drawn and tappable.
@@ -54,6 +56,8 @@ fun CatanBoardView(
     onHexTap: (Int) -> Unit,
     modifier: Modifier = Modifier,
     style: CatanStyle = LocalCatanStyle.current,
+    /** Hexes to light up as having produced on the latest roll. */
+    rolledHexes: Set<Int> = emptySet(),
 ) {
     val measurer = rememberTextMeasurer()
     var size by remember { mutableStateOf(IntSize.Zero) }
@@ -99,6 +103,7 @@ fun CatanBoardView(
         drawRect(color = style.sea)
         drawPorts(state, board, style, measurer)
         drawHexes(state, board, style, measurer)
+        drawRolled(rolledHexes, board, style)
         drawRobber(state, board, style)
         drawRoads(state, board, style)
         drawEdgeTargets(targets, board, style)
@@ -130,6 +135,17 @@ private fun DrawScope.drawHexes(
     }
 }
 
+/** A bright wash and rim on each hex that paid out, drawn over the terrain and under the pieces. */
+private fun DrawScope.drawRolled(hexes: Set<Int>, board: BoardLayout, style: CatanStyle) {
+    for (hex in hexes) {
+        val centre = board.hexCenter(hex)
+        val path = polygon(board.hexCorners(hex).map { insetToward(it, centre, style.hexInset + 0.04f) })
+        drawPath(path, color = style.rolled.copy(alpha = 0.28f))
+        drawPath(path, color = style.pieceOutline, style = Stroke(width = board.radius * 0.13f))
+        drawPath(path, color = style.rolled, style = Stroke(width = board.radius * 0.075f))
+    }
+}
+
 private fun DrawScope.drawToken(
     number: Int,
     at: Pt,
@@ -206,7 +222,7 @@ private fun DrawScope.drawPorts(
         val anchor = board.portAnchor(port.edge)
         val (a, b) = board.edgeEnds(port.edge)
         val tint = port.resource?.let { style.resource.getValue(it) } ?: style.portInk
-        // Two short piers from the marker to the vertices that can use the harbour.
+        // Two piers from the marker to the vertices that can use the harbour.
         for (end in listOf(a, b)) {
             drawLine(
                 color = style.portMarker.copy(alpha = 0.9f),
@@ -224,10 +240,26 @@ private fun DrawScope.drawPorts(
             center = anchor.offset(),
             style = Stroke(width = board.radius * 0.07f),
         )
+        // What the harbour trades: a picture of the resource, or "?" for any.
+        val iconAt = Pt(anchor.x, anchor.y - radius * 0.27f)
+        val iconSize = radius * 0.5f
+        val resource = port.resource
+        if (resource != null) {
+            drawResourceIcon(resource, iconAt, iconSize, tint, style.pieceOutline)
+        } else {
+            drawCentered(
+                measurer = measurer,
+                text = "?",
+                at = iconAt,
+                fontPx = board.radius * style.portText * 1.5f,
+                color = style.portInk,
+                weight = FontWeight.ExtraBold,
+            )
+        }
         drawCentered(
             measurer = measurer,
             text = "${port.ratio}:1",
-            at = anchor,
+            at = Pt(anchor.x, anchor.y + radius * 0.5f),
             fontPx = board.radius * style.portText,
             color = style.portInk,
             weight = FontWeight.Bold,
@@ -235,6 +267,81 @@ private fun DrawScope.drawPorts(
     }
 }
 
+/**
+ * A small pictogram of [resource] centred on [at], about 2·[s] across: a tree,
+ * bricks, a sheep, an ear of wheat or a rock. Drawn with paths so there are no
+ * image assets to ship or scale.
+ */
+private fun DrawScope.drawResourceIcon(resource: Resource, at: Pt, s: Float, fill: Color, line: Color) {
+    val outline = Stroke(width = s * 0.12f)
+    when (resource) {
+        Resource.LUMBER -> {
+            val crown = Path().apply {
+                moveTo(at.x, at.y - s)
+                lineTo(at.x + s * 0.8f, at.y + s * 0.3f)
+                lineTo(at.x - s * 0.8f, at.y + s * 0.3f)
+                close()
+            }
+            drawRect(color = line, topLeft = Offset(at.x - s * 0.14f, at.y + s * 0.3f), size = Size(s * 0.28f, s * 0.6f))
+            drawPath(crown, color = fill)
+            drawPath(crown, color = line, style = outline)
+        }
+
+        Resource.BRICK -> {
+            val w = s * 0.9f
+            val h = s * 0.42f
+            for ((row, shift) in listOf(0f to 0f, 1f to w * 0.5f)) {
+                val top = at.y - h + row * h
+                val left = at.x - w + shift - w * 0.25f
+                for (col in 0..1) {
+                    val x = left + col * w
+                    drawRect(color = fill, topLeft = Offset(x, top), size = Size(w, h))
+                    drawRect(color = line, topLeft = Offset(x, top), size = Size(w, h), style = outline)
+                }
+            }
+        }
+
+        Resource.WOOL -> {
+            for ((dx, dy) in listOf(-0.45f to 0f, 0.1f to -0.25f, 0.5f to 0.05f, 0f to 0.2f)) {
+                drawCircle(color = fill, radius = s * 0.42f, center = Offset(at.x + dx * s, at.y + dy * s))
+            }
+            drawCircle(color = line, radius = s * 0.24f, center = Offset(at.x - s * 0.85f, at.y + s * 0.15f))
+            drawRect(color = line, topLeft = Offset(at.x - s * 0.5f, at.y + s * 0.5f), size = Size(s * 0.14f, s * 0.45f))
+            drawRect(color = line, topLeft = Offset(at.x + s * 0.3f, at.y + s * 0.5f), size = Size(s * 0.14f, s * 0.45f))
+        }
+
+        Resource.GRAIN -> {
+            drawLine(color = line, start = Offset(at.x, at.y + s), end = Offset(at.x, at.y - s * 0.7f), strokeWidth = s * 0.14f)
+            for (i in 0..2) {
+                val y = at.y - s * 0.7f + i * s * 0.5f
+                for (side in listOf(-1f, 1f)) {
+                    val kernel = Path().apply {
+                        moveTo(at.x, y + s * 0.3f)
+                        lineTo(at.x + side * s * 0.6f, y - s * 0.05f)
+                        lineTo(at.x + side * s * 0.15f, y - s * 0.2f)
+                        close()
+                    }
+                    drawPath(kernel, color = fill)
+                    drawPath(kernel, color = line, style = Stroke(width = s * 0.08f))
+                }
+            }
+        }
+
+        Resource.ORE -> {
+            val peak = Path().apply {
+                moveTo(at.x - s, at.y + s * 0.8f)
+                lineTo(at.x - s * 0.3f, at.y - s * 0.6f)
+                lineTo(at.x + s * 0.1f, at.y + s * 0.05f)
+                lineTo(at.x + s * 0.45f, at.y - s * 0.3f)
+                lineTo(at.x + s, at.y + s * 0.8f)
+                close()
+            }
+            drawPath(peak, color = fill)
+            drawPath(peak, color = line, style = outline)
+        }
+    }
+}
+
 // ---------------------------------------------------------------------------
 // Pieces
 // ---------------------------------------------------------------------------

app/src/main/java/org/prolibertate/games/ui/game/catan/CatanGeometry.kt

@@ -102,7 +102,7 @@ object CatanGeometry {
     private const val LATTICE_Y_UNITS = 16
 
     /** Empty space round the island, in hex radii, for the sea and the harbours. */
-    const val MARGIN = 1.15f
+    const val MARGIN = 1.75f
 
     private val boardWidthInRadii = LATTICE_X_UNITS * SQRT3 / 2f + 2 * MARGIN
     private val boardHeightInRadii = LATTICE_Y_UNITS / 2f + 2 * MARGIN
@@ -119,5 +119,5 @@ object CatanGeometry {
 
 private const val SQRT3 = 1.7320508f
 
-/** How far past the coast a harbour marker sits, in hex radii. */
+/** How far past the coast a harbour marker sits, in hex radii. Far enough that its piers are clearly visible. */
-private const val PORT_OFFSET = 0.62f
+internal const val PORT_OFFSET = 1.0f

app/src/main/java/org/prolibertate/games/ui/game/catan/CatanInteraction.kt

@@ -171,6 +171,25 @@ object CatanInteraction {
 
     fun canRoll(legal: List<CatanMove>): Boolean = legal.any { it is RollDice }
 
+    /**
+     * The hexes that paid out for this turn's roll, so the board can light them.
+     * Empty until the turn's roll has happened (the dice left over from the last
+     * turn are not this turn's), on a seven, and for the hex the robber sits on.
+     */
+    fun rolledHexes(state: CatanState): Set<Int> {
+        if (state.lastDice.size != 2) return emptySet()
+        if (state.phase == CatanPhase.AWAIT_ROLL || state.phase == CatanPhase.SETUP_FIRST ||
+            state.phase == CatanPhase.SETUP_SECOND
+        ) {
+            return emptySet()
+        }
+        val total = state.lastDice.sum()
+        if (total == 7) return emptySet()
+        return (0 until CatanBoard.HEX_COUNT)
+            .filter { state.numbers[it] == total && it != state.robber }
+            .toSet()
+    }
+
     fun canEndTurn(legal: List<CatanMove>): Boolean = legal.any { it is EndTurn }
 
     fun canEndFreeRoads(legal: List<CatanMove>): Boolean = legal.any { it is EndFreeRoads }

app/src/main/java/org/prolibertate/games/ui/game/catan/CatanPanels.kt

@@ -11,6 +11,7 @@ import androidx.compose.foundation.layout.FlowRow
 import androidx.compose.foundation.layout.Row
 import androidx.compose.foundation.layout.defaultMinSize
 import androidx.compose.foundation.layout.fillMaxWidth
+import androidx.compose.foundation.layout.height
 import androidx.compose.foundation.layout.padding
 import androidx.compose.foundation.layout.size
 import androidx.compose.foundation.rememberScrollState
@@ -18,17 +19,25 @@ import androidx.compose.foundation.shape.CircleShape
 import androidx.compose.foundation.shape.RoundedCornerShape
 import androidx.compose.foundation.verticalScroll
 import androidx.compose.material3.Button
+import androidx.compose.material3.DropdownMenu
+import androidx.compose.material3.DropdownMenuItem
 import androidx.compose.material3.FilledTonalButton
 import androidx.compose.material3.MaterialTheme
 import androidx.compose.material3.OutlinedButton
 import androidx.compose.material3.Text
 import androidx.compose.runtime.Composable
+import androidx.compose.runtime.getValue
+import androidx.compose.runtime.mutableStateOf
+import androidx.compose.runtime.remember
+import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
 import androidx.compose.ui.draw.clip
 import androidx.compose.ui.graphics.Color
 import androidx.compose.ui.text.font.FontWeight
+import androidx.compose.ui.text.TextStyle
 import androidx.compose.ui.text.style.TextAlign
+import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.dp
 import androidx.compose.ui.unit.sp
 import org.prolibertate.games.game.catan.CatanPhase
@@ -118,11 +127,18 @@ fun CatanHand(
 
 /**
  * One player's public standing: colour, name, points, how many cards they hold
- * (not which), development cards, knights and their longest road.
+ * (not which), and — in the roomier layout — development cards, knights and
+ * their longest road.
+ *
+ * **Fixed height.** Every line is always present (blank when there is nothing to
+ * say) and never wraps, so the card is the same height whatever the game is
+ * doing. The board is given whatever room is left, so anything that made this
+ * card taller or shorter would rescale the island under the player's thumb.
  *
  * [points] is passed in rather than computed here because the local player's
  * own count includes hidden victory-point cards and everyone else's does not;
- * the screen decides which.
+ * the screen decides which. [compact] is the narrow portrait strip (four cards
+ * across a phone); the default has room for the detail lines.
  */
 @Composable
 fun CatanPlayerCard(
@@ -132,6 +148,7 @@ fun CatanPlayerCard(
     points: Int,
     modifier: Modifier = Modifier,
     style: CatanStyle = LocalCatanStyle.current,
+    compact: Boolean = false,
 ) {
     val onTurn = state.turn == seat && state.phase != CatanPhase.GAME_OVER
     val shape = RoundedCornerShape(12.dp)
@@ -155,39 +172,54 @@ fun CatanPlayerCard(
                     .background(style.seats[seat % style.seats.size])
                     .border(1.dp, style.pieceOutline, CircleShape),
             )
-            Text(
+            CardLine(seats.label(seat), MaterialTheme.typography.labelLarge, FontWeight.Bold)
-                text = seats.label(seat),
+        }
-                fontWeight = FontWeight.Bold,
+        CardLine("$points VP", MaterialTheme.typography.titleMedium, FontWeight.Bold)
-                maxLines = 1,
+        if (compact) {
-                style = MaterialTheme.typography.labelLarge,
+            CardLine("${state.resourceCount(seat)} cards", MaterialTheme.typography.bodySmall)
+        } else {
+            CardLine(
+                "${state.resourceCount(seat)} cards · ${state.devHandCounts[seat]} dev",
+                MaterialTheme.typography.bodySmall,
+            )
+            CardLine(
+                "Knights ${state.knightsPlayed[seat]} · Road ${CatanRules.longestRoadFor(state, seat)}",
+                MaterialTheme.typography.bodySmall,
             )
         }
-        Text(
-            text = "$points VP",
-            style = MaterialTheme.typography.titleMedium,
-            fontWeight = FontWeight.Bold,
-        )
-        Text(
-            text = "${state.resourceCount(seat)} cards · ${state.devHandCounts[seat]} dev",
-            style = MaterialTheme.typography.bodySmall,
-        )
-        Text(
-            text = "Knights ${state.knightsPlayed[seat]} · Road ${CatanRules.longestRoadFor(state, seat)}",
-            style = MaterialTheme.typography.bodySmall,
-        )
         val awards = buildList {
-            if (state.longestRoadOwner == seat) add("Longest road")
+            if (state.longestRoadOwner == seat) add(if (compact) "Road" else "Longest road")
-            if (state.largestArmyOwner == seat) add("Largest army")
+            if (state.largestArmyOwner == seat) add(if (compact) "Army" else "Largest army")
         }
-        if (awards.isNotEmpty()) {
+        // Always drawn, so the card does not grow when somebody takes an award.
-            Text(
+        CardLine(
-                text = awards.joinToString(" · "),
+            text = awards.joinToString(" · ").ifEmpty { BLANK },
             style = MaterialTheme.typography.labelSmall,
+            weight = FontWeight.Bold,
             color = MaterialTheme.colorScheme.primary,
-                fontWeight = FontWeight.Bold,
         )
     }
 }
+
+/** A non-breaking space: a line of text with nothing in it, still one line tall. */
+private const val BLANK = "\u00A0"
+
+/** One line of a player card: never wraps, so the card's height cannot change. */
+@Composable
+private fun CardLine(
+    text: String,
+    style: TextStyle,
+    weight: FontWeight? = null,
+    color: Color = Color.Unspecified,
+) {
+    Text(
+        text = text,
+        style = style,
+        fontWeight = weight,
+        color = color,
+        maxLines = 1,
+        overflow = TextOverflow.Ellipsis,
+    )
 }
 
 // ---------------------------------------------------------------------------
@@ -221,15 +253,14 @@ fun CatanDice(dice: List<Int>, modifier: Modifier = Modifier) {
                 )
             }
         }
-        if (dice.size == 2) {
+        // Always drawn ("= –" before the first roll) so the row never changes width.
         Text(
-                text = "= ${dice.sum()}",
+            text = if (dice.size == 2) "= ${dice.sum()}" else "= –",
             style = MaterialTheme.typography.titleMedium,
             fontWeight = FontWeight.Bold,
         )
     }
 }
-}
 
 // ---------------------------------------------------------------------------
 // Actions
@@ -238,7 +269,6 @@ fun CatanDice(dice: List<Int>, modifier: Modifier = Modifier) {
 /** What the action bar offers right now. Built by the screen from [CatanInteraction]. */
 data class CatanActions(
     val canRoll: Boolean = false,
-    val showTurnActions: Boolean = false,
     val canBuild: Set<BuildKind> = emptySet(),
     val building: BuildKind? = null,
     val canBuyCard: Boolean = false,
@@ -250,7 +280,16 @@ data class CatanActions(
     val canRepickSetup: Boolean = false,
 )
 
-/** The buttons for whatever the player can do now. Pure display: every press is a lambda. */
+/**
+ * The buttons for whatever the player can do now. Pure display: every press is a lambda.
+ *
+ * **The bar never changes size.** The top row holds the one "primary" action
+ * (roll, end turn, done with roads, cancel) and keeps its height when it is
+ * empty; the second row is always all six buttons, greyed out when they do not
+ * apply. Buttons appearing and disappearing used to resize this area and, with
+ * it, the board above — so nothing here may be conditionally *present*, only
+ * conditionally *enabled*.
+ */
 @OptIn(ExperimentalLayoutApi::class)
 @Composable
 fun CatanActionBar(
@@ -264,33 +303,48 @@ fun CatanActionBar(
     onEndFreeRoads: () -> Unit,
     onRepickSetup: () -> Unit,
     modifier: Modifier = Modifier,
+    /** Small screens: fold Road / Settlement / City into one "Build" button with a menu. */
+    compact: Boolean = false,
 ) {
-    FlowRow(
+    Column(modifier = modifier.fillMaxWidth(), verticalArrangement = Arrangement.spacedBy(8.dp)) {
-        modifier = modifier.fillMaxWidth(),
+        Row(
+            modifier = Modifier.fillMaxWidth().height(PRIMARY_ROW_HEIGHT),
+            verticalAlignment = Alignment.CenterVertically,
             horizontalArrangement = Arrangement.spacedBy(8.dp),
-        verticalArrangement = Arrangement.spacedBy(8.dp),
         ) {
             if (actions.canRoll) Button(onClick = onRoll) { Text(CatanText.ROLL) }
-
+            if (actions.canRepickSetup) OutlinedButton(onClick = onRepickSetup) { Text(CatanText.CANCEL) }
-        if (actions.canRepickSetup) {
-            OutlinedButton(onClick = onRepickSetup) { Text(CatanText.CANCEL) }
-        }
-
-        if (actions.showTurnActions) {
-            BuildButton(BuildKind.ROAD, CatanText.ROAD, CatanText.ROAD_COST, actions, onBuild)
-            BuildButton(BuildKind.SETTLEMENT, CatanText.SETTLEMENT, CatanText.SETTLEMENT_COST, actions, onBuild)
-            BuildButton(BuildKind.CITY, CatanText.CITY, CatanText.CITY_COST, actions, onBuild)
-            OutlinedButton(onClick = onBuyCard, enabled = actions.canBuyCard) {
-                LabelWithCost(CatanText.BUY_CARD, CatanText.DEV_COST)
-            }
-            OutlinedButton(onClick = onPlayCard, enabled = actions.canPlayCard) { Text(CatanText.PLAY_CARD) }
-            OutlinedButton(onClick = onTrade, enabled = actions.canTrade) { Text(CatanText.TRADE) }
-        }
-
             if (actions.canEndFreeRoads) Button(onClick = onEndFreeRoads) { Text(CatanText.STOP_ROADS) }
             if (actions.canEndTurn) Button(onClick = onEndTurn) { Text(CatanText.END_TURN) }
         }
+
+        FlowRow(
+            modifier = Modifier.fillMaxWidth(),
+            horizontalArrangement = Arrangement.spacedBy(8.dp),
+            verticalArrangement = Arrangement.spacedBy(8.dp),
+        ) {
+            if (compact) {
+                BuildMenuButton(actions, onBuild)
+            } else {
+                BuildButton(BuildKind.ROAD, CatanText.ROAD, CatanText.ROAD_COST, actions, onBuild)
+                BuildButton(BuildKind.SETTLEMENT, CatanText.SETTLEMENT, CatanText.SETTLEMENT_COST, actions, onBuild)
+                BuildButton(BuildKind.CITY, CatanText.CITY, CatanText.CITY_COST, actions, onBuild)
             }
+            OutlinedButton(onClick = onBuyCard, enabled = actions.canBuyCard) {
+                LabelWithCost(CatanText.BUY_CARD, CatanText.DEV_COST)
+            }
+            OutlinedButton(onClick = onPlayCard, enabled = actions.canPlayCard) {
+                LabelWithCost(CatanText.PLAY_CARD, CatanText.NO_COST)
+            }
+            OutlinedButton(onClick = onTrade, enabled = actions.canTrade) {
+                LabelWithCost(CatanText.TRADE, CatanText.NO_COST)
+            }
+        }
+    }
+}
+
+/** Room for one button, held whether or not there is one to show. */
+private val PRIMARY_ROW_HEIGHT = 48.dp
 
 @Composable
 private fun BuildButton(
@@ -310,6 +364,52 @@ private fun BuildButton(
     }
 }
 
+/**
+ * The small-screen stand-in for the three build buttons: one "Build" button
+ * whose menu lists Road, Settlement and City with their costs. While a build
+ * mode is armed the button shows which, and choosing that entry again cancels it.
+ */
+@Composable
+private fun BuildMenuButton(actions: CatanActions, onBuild: (BuildKind?) -> Unit) {
+    var open by remember { mutableStateOf(false) }
+    val armed = actions.building
+    val anyEnabled = actions.canBuild.isNotEmpty() || armed != null
+    val label: @Composable () -> Unit = {
+        LabelWithCost(CatanText.BUILD, armed?.let { buildLabel(it) } ?: CatanText.NO_COST)
+    }
+    Box {
+        if (armed != null) {
+            FilledTonalButton(onClick = { open = true }, enabled = anyEnabled) { label() }
+        } else {
+            OutlinedButton(onClick = { open = true }, enabled = anyEnabled) { label() }
+        }
+        DropdownMenu(expanded = open, onDismissRequest = { open = false }) {
+            for (kind in BuildKind.entries) {
+                DropdownMenuItem(
+                    text = { LabelWithCost(buildLabel(kind), buildCost(kind)) },
+                    enabled = kind in actions.canBuild,
+                    onClick = {
+                        open = false
+                        onBuild(if (armed == kind) null else kind)
+                    },
+                )
+            }
+        }
+    }
+}
+
+private fun buildLabel(kind: BuildKind): String = when (kind) {
+    BuildKind.ROAD -> CatanText.ROAD
+    BuildKind.SETTLEMENT -> CatanText.SETTLEMENT
+    BuildKind.CITY -> CatanText.CITY
+}
+
+private fun buildCost(kind: BuildKind): String = when (kind) {
+    BuildKind.ROAD -> CatanText.ROAD_COST
+    BuildKind.SETTLEMENT -> CatanText.SETTLEMENT_COST
+    BuildKind.CITY -> CatanText.CITY_COST
+}
+
 @Composable
 private fun LabelWithCost(label: String, cost: String) {
     Column(horizontalAlignment = Alignment.CenterHorizontally) {

app/src/main/java/org/prolibertate/games/ui/game/catan/CatanPreviews.kt

@@ -112,14 +112,13 @@ private fun PanelsPreview() {
     Column(Modifier.padding(8.dp), verticalArrangement = Arrangement.spacedBy(8.dp)) {
         Row(Modifier.fillMaxWidth(), horizontalArrangement = Arrangement.spacedBy(6.dp)) {
             (0 until state.playerCount).forEach { seat ->
-                CatanPlayerCard(state, seat, seats, points[seat], Modifier.weight(1f))
+                CatanPlayerCard(state, seat, seats, points[seat], Modifier.weight(1f), compact = true)
             }
         }
         CatanHand(state, seat = 0)
         CatanDice(state.lastDice)
         CatanActionBar(
             actions = CatanActions(
-                showTurnActions = true,
                 canBuild = setOf(BuildKind.ROAD, BuildKind.CITY),
                 building = BuildKind.ROAD,
                 canBuyCard = true,

app/src/main/java/org/prolibertate/games/ui/game/catan/CatanScreen.kt

@@ -24,6 +24,8 @@ import androidx.compose.runtime.remember
 import androidx.compose.runtime.setValue
 import androidx.compose.ui.Alignment
 import androidx.compose.ui.Modifier
+import androidx.compose.ui.graphics.Color
+import androidx.compose.ui.text.style.TextOverflow
 import androidx.compose.ui.unit.dp
 import org.prolibertate.games.game.catan.AcceptTrade
 import org.prolibertate.games.game.catan.BuyDevCard
@@ -130,7 +132,6 @@ fun CatanScreen(
     val playing = current.phase == CatanPhase.PLAYING && legal.isNotEmpty()
     val actions = CatanActions(
         canRoll = CatanInteraction.canRoll(legal),
-        showTurnActions = playing,
         canBuild = CatanInteraction.canBuild(legal),
         building = building,
         canBuyCard = CatanInteraction.canBuyDevCard(legal),
@@ -140,6 +141,7 @@ fun CatanScreen(
         canEndFreeRoads = CatanInteraction.canEndFreeRoads(legal),
         canRepickSetup = setupVertex != null,
     )
+    val rolledHexes = CatanInteraction.rolledHexes(current)
     val prompt = CatanText.prompt(current, seats, setupVertexChosen = setupVertex != null, building = building)
 
     val handle: (TapOutcome) -> Unit = { outcome ->
@@ -160,6 +162,8 @@ fun CatanScreen(
         ScreenScaffold(title = CatanText.TITLE, onBack = onExit, actions = endGameAction) { modifier ->
             BoxWithConstraints(modifier = modifier) {
                 val wide = maxWidth > maxHeight * 1.1f
+                // Phones (either way up) get the one-button build menu.
+                val compactBuild = !wide || maxWidth < 600.dp
 
                 val board: @Composable (Modifier) -> Unit = { boardModifier ->
                     CatanBoardView(
@@ -171,6 +175,7 @@ fun CatanScreen(
                         onHexTap = { handle(CatanInteraction.onHexTap(it, legal)) },
                         modifier = boardModifier,
                         style = style,
+                        rolledHexes = rolledHexes,
                     )
                 }
                 val players: @Composable (Boolean) -> Unit = { grid ->
@@ -194,6 +199,7 @@ fun CatanScreen(
                                 legal.firstOrNull { m -> m is EndFreeRoads }?.let(submit)
                             },
                             onRepickSetup = { setupVertex = null },
+                            compact = compactBuild,
                         )
                     }
                 }
@@ -275,6 +281,7 @@ private fun PlayerCards(
                         points = pointsOf(seat),
                         modifier = Modifier.weight(1f),
                         style = style,
+                        compact = !twoPerRow,
                     )
                 }
                 // Keep an odd last row's card the same width as the others.
@@ -284,6 +291,14 @@ private fun PlayerCards(
     }
 }
 
+/**
+ * The one line telling the player what is going on, and the dice.
+ *
+ * **Fixed height.** The text always occupies exactly two lines (padded when it is
+ * shorter, clipped when it is longer) and a refused move replaces the prompt
+ * rather than adding to it, so this row is the same height whatever is said and
+ * the board below it never moves.
+ */
 @Composable
 private fun PromptRow(prompt: String, notice: String?, state: CatanState) {
     Row(
@@ -291,16 +306,15 @@ private fun PromptRow(prompt: String, notice: String?, state: CatanState) {
         verticalAlignment = Alignment.CenterVertically,
         horizontalArrangement = Arrangement.spacedBy(8.dp),
     ) {
-        Column(modifier = Modifier.weight(1f)) {
-            Text(prompt, style = MaterialTheme.typography.bodyMedium)
-            if (notice != null) {
         Text(
-                    notice,
+            text = notice ?: prompt,
-                    style = MaterialTheme.typography.bodySmall,
+            style = MaterialTheme.typography.bodyMedium,
-                    color = MaterialTheme.colorScheme.error,
+            color = if (notice != null) MaterialTheme.colorScheme.error else Color.Unspecified,
+            minLines = 2,
+            maxLines = 2,
+            overflow = TextOverflow.Ellipsis,
+            modifier = Modifier.weight(1f),
         )
-            }
-        }
         CatanDice(state.lastDice)
     }
 }

app/src/main/java/org/prolibertate/games/ui/game/catan/CatanStyle.kt

@@ -36,6 +36,8 @@ data class CatanStyle(
     val tokenHotInk: Color,
     /** The robber's pawn. */
     val robber: Color,
+    /** Outline and wash on hexes that produced for the latest dice roll. */
+    val rolled: Color,
     /** Harbour marker disc and its ink. */
     val portMarker: Color,
     val portInk: Color,
@@ -64,12 +66,12 @@ data class CatanStyle(
     val citySize: Float = 0.42f,
     val tokenRadius: Float = 0.36f,
     val robberSize: Float = 0.34f,
-    val portRadius: Float = 0.34f,
+    val portRadius: Float = 0.46f,
     val targetRadius: Float = 0.20f,
     /** How close a tap must land to a vertex / edge / hex centre to count. */
     val tapReach: Float = 0.55f,
     val tokenText: Float = 0.34f,
-    val portText: Float = 0.26f,
+    val portText: Float = 0.27f,
 )
 
 /** The light palette, which is also the reference for the dark one. */
@@ -88,6 +90,7 @@ private val LightStyle = CatanStyle(
     tokenInk = Color(0xFF2B2B2B),
     tokenHotInk = Color(0xFFC62828),
     robber = Color(0xFF263238),
+    rolled = Color(0xFFFFFFFF),
     portMarker = Color(0xFFFFF8E1),
     portInk = Color(0xFF2B2B2B),
     resource = mapOf(

app/src/main/java/org/prolibertate/games/ui/game/catan/CatanText.kt

@@ -103,6 +103,12 @@ object CatanText {
     const val CONFIRM = "Confirm"
     const val STOP_ROADS = "Done with roads"
     const val BUILD = "Build"
+
+    /**
+     * The empty second line of a button that has no cost, so every button in the
+     * action bar is the same height. A non-breaking space: blank, but a line.
+     */
+    const val NO_COST = "\u00A0"
     const val YOUR_HAND = "Your hand"
     const val CARDS = "cards"
     const val ACCEPT = "Accept"

app/src/test/java/org/prolibertate/games/game/catan/CatanRulesTest.kt

@@ -340,6 +340,89 @@ class CatanRulesTest {
         )
     }
 
+    /** Seat 0 owns a settlement at vertex 0 and a two-road chain v0 - w - x; `beyond` continues past x. */
+    private data class Chain(val state: CatanState, val x: Int, val beyond: Int, val spur: Int?)
+
+    private fun chain(): Chain {
+        val e1 = CatanBoard.VERTEX_EDGES[0][0]
+        val w = CatanBoard.otherEnd(e1, 0)
+        val e2 = CatanBoard.VERTEX_EDGES[w].first { it != e1 }
+        val x = CatanBoard.otherEnd(e2, w)
+        val beyond = CatanBoard.VERTEX_EDGES[x].first { it != e2 }
+        val spur = CatanBoard.VERTEX_EDGES[w].firstOrNull { it != e1 && it != e2 }
+        val state = craft()
+            .copy(resources = hands(hand(Resource.LUMBER to 5, Resource.BRICK to 5)))
+            .withBuilding(0, BuildingType.SETTLEMENT, 0)
+            .withRoad(e1, 0)
+            .withRoad(e2, 0)
+        return Chain(state, x, beyond, spur)
+    }
+
+    @Test
+    fun `a road cannot be built past an opponent's settlement`() {
+        val (open, x, beyond, spur) = chain()
+        assertTrue("open crossing: the road continues", BuildRoad(beyond) in CatanRules.legalMoves(open, 0))
+
+        val blocked = open.withBuilding(x, BuildingType.SETTLEMENT, 1)
+        assertFalse(
+            "an opponent's settlement on the crossing breaks the network",
+            BuildRoad(beyond) in CatanRules.legalMoves(blocked, 0),
+        )
+        // The same through a city, and while laying free roads from Road Building.
+        val city = open.withBuilding(x, BuildingType.CITY, 1)
+        assertFalse(BuildRoad(beyond) in CatanRules.legalMoves(city, 0))
+        val free = blocked.copy(phase = CatanPhase.FREE_ROADS, pendingFreeRoads = 2)
+        assertFalse(BuildRoad(beyond) in CatanRules.legalMoves(free, 0))
+        // The rest of the network is untouched: the spur at the other crossing still works.
+        if (spur != null) assertTrue(BuildRoad(spur) in CatanRules.legalMoves(blocked, 0))
+    }
+
+    @Test
+    fun `your own settlement on the crossing does not block your road`() {
+        val (open, x, beyond, _) = chain()
+        val own = open.withBuilding(x, BuildingType.SETTLEMENT, 0)
+        assertTrue(BuildRoad(beyond) in CatanRules.legalMoves(own, 0))
+    }
+
+    @Test
+    fun `a player runs out of pieces`() {
+        val rich = hands(
+            hand(
+                Resource.LUMBER to 9, Resource.BRICK to 9, Resource.WOOL to 9,
+                Resource.GRAIN to 9, Resource.ORE to 9,
+            ),
+        )
+
+        // Roads: fifteen, and no sixteenth - in the main phase or from Road Building.
+        var roads = craft().copy(resources = rich).withBuilding(0, BuildingType.SETTLEMENT, 0)
+        repeat(14) {
+            roads = roads.withRoad(CatanRules.legalMoves(roads, 0).filterIsInstance<BuildRoad>().first().edge, 0)
+        }
+        assertTrue("fourteen laid: one more is allowed", CatanRules.legalMoves(roads, 0).any { it is BuildRoad })
+        roads = roads.withRoad(CatanRules.legalMoves(roads, 0).filterIsInstance<BuildRoad>().first().edge, 0)
+        assertEquals(15, roads.roads.count { it == 0 })
+        assertTrue("fifteen laid: none left", CatanRules.legalMoves(roads, 0).none { it is BuildRoad })
+        val free = roads.copy(phase = CatanPhase.FREE_ROADS, pendingFreeRoads = 2)
+        assertEquals(listOf<CatanMove>(EndFreeRoads), CatanRules.legalMoves(free, 0))
+
+        // Settlements: five.
+        val homes = scattered(7)
+        var settled = craft().copy(resources = rich)
+        for (i in 0 until 4) settled = settled.withBuilding(homes[i], BuildingType.SETTLEMENT, 0)
+        settled = settled.withRoad(CatanBoard.VERTEX_EDGES[homes[5]][0], 0)
+        assertTrue("four standing: a fifth is allowed", BuildSettlement(homes[5]) in CatanRules.legalMoves(settled, 0))
+        settled = settled.withBuilding(homes[4], BuildingType.SETTLEMENT, 0)
+        assertFalse("five standing: no sixth", BuildSettlement(homes[5]) in CatanRules.legalMoves(settled, 0))
+
+        // Cities: four. A raised settlement returns to the supply, so five settlements stays possible.
+        var raised = craft().copy(resources = rich)
+        for (i in 0 until 3) raised = raised.withBuilding(homes[i], BuildingType.CITY, 0)
+        raised = raised.withBuilding(homes[3], BuildingType.SETTLEMENT, 0)
+        assertTrue("three cities: a fourth is allowed", BuildCity(homes[3]) in CatanRules.legalMoves(raised, 0))
+        raised = raised.withBuilding(homes[3], BuildingType.CITY, 0).withBuilding(homes[4], BuildingType.SETTLEMENT, 0)
+        assertFalse("four cities: no fifth", BuildCity(homes[4]) in CatanRules.legalMoves(raised, 0))
+    }
+
     @Test
     fun `a settlement needs an open vertex on the network, a city one of yours`() {
         val base = craft()

app/src/test/java/org/prolibertate/games/ui/game/catan/CatanGeometryTest.kt

@@ -111,7 +111,7 @@ class CatanGeometryTest {
             val anchor = layout.portAnchor(e)
             val mid = layout.edgeMidpoint(e)
             assertTrue("harbour on edge $e should be past the coast", dist(anchor, centre) > dist(mid, centre))
-            assertTrue("and not floating far from it", abs(dist(anchor, mid) - layout.radius * 0.62f) < 1f)
+            assertTrue("and not floating far from it", abs(dist(anchor, mid) - layout.radius * PORT_OFFSET) < 1f)
         }
     }
 }

app/src/test/java/org/prolibertate/games/ui/game/catan/CatanInteractionTest.kt

@@ -322,4 +322,27 @@ class CatanInteractionTest {
         val short = pending.withHand(1, hand())
         assertEquals(false to true, CatanInteraction.tradeResponses(CatanRules.legalMoves(short, 1)))
     }
+
+    // --- Rolled-hex highlight --------------------------------------------------
+
+    @Test
+    fun `rolled hexes are those carrying the number, minus the robber's`() {
+        val base = playing(turn = 0)
+        val number = base.numbers.first { it != 0 && it != 7 }
+        val state = base.copy(lastDice = if (number <= 7) listOf(number - 1, 1) else listOf(6, number - 6))
+        val all = (0 until CatanBoard.HEX_COUNT).filter { state.numbers[it] == number }
+        assertTrue(all.isNotEmpty())
+        assertEquals(all.filter { it != state.robber }.toSet(), CatanInteraction.rolledHexes(state))
+        val blocked = state.copy(robber = all.first())
+        assertFalse(all.first() in CatanInteraction.rolledHexes(blocked))
+    }
+
+    @Test
+    fun `nothing is highlighted before this turn's roll, on a seven, or in setup`() {
+        val rolled = playing(turn = 0).copy(lastDice = listOf(3, 3))
+        assertTrue(CatanInteraction.rolledHexes(rolled.copy(phase = CatanPhase.AWAIT_ROLL)).isEmpty())
+        assertTrue(CatanInteraction.rolledHexes(rolled.copy(lastDice = listOf(3, 4))).isEmpty())
+        assertTrue(CatanInteraction.rolledHexes(rolled.copy(phase = CatanPhase.SETUP_FIRST)).isEmpty())
+        assertTrue(CatanInteraction.rolledHexes(rolled.copy(lastDice = emptyList())).isEmpty())
+    }
 }

docs/RULES-catan.md

@@ -159,7 +159,19 @@ its edge.
 A settlement goes on an **empty vertex** at least two edges from every standing
 building and connected to the seat's own road network. A city upgrades one of
 the seat's own settlements. A road goes on an empty edge that connects to the
-seat's network (a road or a building at one of its ends).
+seat's network: it must start from a crossing where the seat has a building, or
+where one of its roads ends.
+
+**An opponent's settlement or city on a crossing breaks the network there.** A
+road cannot be laid past it, even from a crossing where one of your own roads
+ends — only a crossing you own a building on is a way through. The same rule
+applies to the free roads of a Road Building card, and it is the same wall that
+cuts Longest Road (below).
+
+**Pieces are limited**: each player has **15 roads, 5 settlements and 4 cities**.
+A player who has laid them all cannot build another of that kind. Raising a
+settlement into a city returns the settlement to the supply, so the five
+settlements remain available to be laid again.
 
 The development deck is the published 25 cards: **14 Knights, 2 Road Building,
 2 Monopoly, 2 Year of Plenty, 5 Victory Point**. Cards are bought blind from the

docs/UI-catan.md

@@ -71,6 +71,14 @@ screen's UI state. The legal-move list stays the gate.
    size of the deck; it is not known to a client. Card *counts* (`resourceCount`,
    `devHandCounts`) are public.
 5. **The state is immutable.** Never mutate it; submit a move.
+6. **The layout must not move.** Everything outside the board has a *fixed
+   height*, and the board takes whatever is left, so the island's scale is the
+   same all game. Concretely: a control is *enabled or disabled*, never
+   *present or absent* (the action bar always shows every button); text that can
+   vary in length is pinned to a fixed number of lines (`minLines = maxLines`);
+   a line that is sometimes empty is still drawn (a non-breaking space), as the
+   award line on a player card is. A change that makes any non-board element
+   taller or shorter at runtime will rescale the board under the player's thumb.
 
 ## Interaction model (what the player actually does)