v0.4.8 — the Limits bound the whole district, the nine spots really are nine, and an action points at its square

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01YQAJ4dND7enLj54eLyiF2C

src/web/game.ts

@@ -87,9 +87,36 @@ export type ActionGroup = {
    * from the browser, which needs the whole `GameState`. A remote client has no state, so the menu
    * carries it. See `docs/architecture/multiplayer.md` §5.
    */
-  actions: { index: number; label: string; tip?: string }[];
+  /**
+   * `coord` is the square the action HAPPENS ON, when it happens on one.
+   *
+   * Carried as data rather than left inside the label. Half these buttons are near-identical
+   * sentences distinguished only by a coordinate — "(1,3)" against "(-1,3)" — and picking the wrong
+   * one is recoverable in solitaire, where Undo is a click, and a disaster in a multiplayer game
+   * where it is not. The page hovers the matching square on the board instead of asking the player
+   * to read the row and column off the button. Reported by Jesse.
+   *
+   * Resolved HERE for the same reason `tip` is: a remote client holds no `GameState` and cannot look
+   * up where a tray is standing. See `docs/architecture/multiplayer.md` §5.
+   */
+  actions: { index: number; label: string; tip?: string; coord?: { row: number; col: number } }[];
 };
 
+/**
+ * The square an intent acts on, or null when it acts on none.
+ *
+ * Only squares the intent NAMES. A card played out on the Mainline (`node`) is not a district
+ * coordinate and must not be treated as one — that confusion is exactly why `placement` and `node`
+ * are separate fields on the intent (see `intents.ts`) — and an action like ending a turn has no
+ * square at all.
+ */
+export function coordOf(i: Intent): { row: number; col: number } | null {
+  if ('at' in i) return i.at;
+  if ('to' in i) return i.to;
+  if (i.type === 'card.play' && i.placement) return i.placement;
+  return null;
+}
+
 export type Game = {
   state: GameState;
   seed: number;
@@ -212,7 +239,13 @@ export function actionGroups(game: Game): { options: Intent[]; groups: ActionGro
    * to survive every edit to a line nobody would think to check. One stray byte and every crew's
    * moves silently collapsed back into a single group. The tray is data; it travels as data.
    */
-  type Entry = { index: number; label: string; tip?: string; trayId?: string };
+  type Entry = {
+    index: number;
+    label: string;
+    tip?: string;
+    trayId?: string;
+    coord?: { row: number; col: number };
+  };
   const byKind = new Map<string, Entry[]>();
   options.forEach((intent, index) => {
     const label = describeIntent(game.state, intent);
@@ -227,14 +260,26 @@ export function actionGroups(game: Game): { options: Intent[]; groups: ActionGro
      * on the crew as well makes the de-duplication per crew, which is what it always meant.
      */
     if (!list.some((a) => a.label === label && a.trayId === trayId)) {
-      list.push({ index, label, ...(tip ? { tip } : {}), ...(trayId ? { trayId } : {}) });
+      const coord = coordOf(intent);
+      list.push({
+        index,
+        label,
+        ...(tip ? { tip } : {}),
+        ...(trayId ? { trayId } : {}),
+        ...(coord ? { coord } : {}),
+      });
     }
     byKind.set(intent.type, list);
   });
 
   /** Groups take the plain shape; the crew was only ever needed to split them. */
   const plain = (entries: Entry[]): ActionGroup['actions'] =>
-    entries.map(({ index, label, tip }) => ({ index, label, ...(tip ? { tip } : {}) }));
+    entries.map(({ index, label, tip, coord }) => ({
+      index,
+      label,
+      ...(tip ? { tip } : {}),
+      ...(coord ? { coord } : {}),
+    }));
 
   const groups: ActionGroup[] = [];
   const used = new Set<string>();