Add exhaust keyword to playCard

src/state.js

@@ -164,12 +164,20 @@ export function playCard(state, handIndex, opts = {}) {
   const card = getCard(cardId);
   if (player.energy < card.cost) return null;
 
+  if (card.keywords?.includes("unplayable")) return null;
+
   const hand = [...player.hand];
   hand.splice(handIndex, 1);
-  const discardPile = [...player.discardPile, cardId];
+  const exhausted = card.keywords?.includes("exhaust");
+  const discardPile = exhausted
+    ? [...player.discardPile]
+    : [...player.discardPile, cardId];
+  const exhaustPile = exhausted
+    ? [...player.exhaustPile, cardId]
+    : [...player.exhaustPile];
   const energy = player.energy - card.cost;
 
-  const updatedPlayer = { ...player, hand, discardPile, energy };
+  const updatedPlayer = { ...player, hand, discardPile, exhaustPile, energy };
   const players = state.players.map((p, i) =>
     i === playerIndex ? updatedPlayer : p,
   );

src/state.test.js

@@ -316,3 +316,41 @@ describe("createCombatFromRun", () => {
     expect(state.enemy).toBe(state.enemies[0]);
   });
 });
+
+describe("playCard - exhaust", () => {
+  test("exhaust card goes to exhaustPile instead of discardPile", () => {
+    let state = createCombatState("ironclad", "jaw_worm");
+    state = drawCards(state, 5);
+    // manually put true_grit in hand
+    const player = {
+      ...state.player,
+      hand: [...state.player.hand, "true_grit"],
+    };
+    state = { ...state, player, players: [player] };
+    const handIndex = state.player.hand.indexOf("true_grit");
+    const discardBefore = [...state.player.discardPile];
+    const next = playCard(state, handIndex);
+    expect(next.player.hand).toHaveLength(state.player.hand.length - 1);
+    expect(next.player.exhaustPile).toContain("true_grit");
+    expect(next.player.discardPile).toEqual(discardBefore);
+    expect(next.player.energy).toBe(state.player.energy - 1);
+  });
+});
+
+describe("playCard - unplayable", () => {
+  test("unplayable card cannot be played", () => {
+    let state = createCombatState("ironclad", "jaw_worm");
+    state = drawCards(state, 5);
+    // manually put tactician in hand
+    const player = {
+      ...state.player,
+      hand: [...state.player.hand, "tactician"],
+    };
+    state = { ...state, player, players: [player] };
+    const handIndex = state.player.hand.indexOf("tactician");
+    const handBefore = [...state.player.hand];
+    const result = playCard(state, handIndex);
+    expect(result).toBeNull();
+    expect(state.player.hand).toEqual(handBefore);
+  });
+});