Initial pass at Golden Pack.

internal/ai/shop.go

@@ -18,7 +18,26 @@ func (cx *ctx) applyTemplateShopEffects(deck []game.Card, c game.Card, trigger g
 		}
 		switch e.Action {
 		case game.ActionGainApple:
-			for range max(e.Count, 1) {
+			n := max(e.Count, 1)
+			switch e.Per {
+			case game.PerShopFaintPets:
+				n *= countShopFaintPets(cx.v.ShopRow)
+			case game.PerBuysThisRound:
+				// This buy will bump the counter, so count it (Blue-Ringed Octopus).
+				n *= cx.me.BuysThisRound + 1
+			}
+			for range n {
+				deck = append(deck, cx.simApple())
+			}
+		case game.ActionRevealForApples:
+			// Cockatoo: the bot would reveal its highest-power other pet.
+			best := 0
+			for _, d := range deck {
+				if d.IsPet() && d.ID != c.ID && d.Power > best {
+					best = d.Power
+				}
+			}
+			for range best {
 				deck = append(deck, cx.simApple())
 			}
 		case game.ActionDoubleApples:
@@ -31,11 +50,54 @@ func (cx *ctx) applyTemplateShopEffects(deck []game.Card, c game.Card, trigger g
 			for range apples {
 				deck = append(deck, cx.simApple())
 			}
+		case game.ActionApplesInPlay:
+			// Golden pack (Hercules Beetle, sold): in-play apples aren't in the
+			// deck, but they buff the front pet, so approximate them as deck
+			// apples for scoring. MinRound is already gated above.
+			for range max(e.Count, 1) {
+				deck = append(deck, cx.simApple())
+			}
+		case game.ActionBuyTopFree:
+			// Golden pack (Stoat): grabs an unknown top-of-deck card; approximate
+			// with a sampled card of the current tier.
+			pool := cx.unseenPool(cx.v.Round)
+			if len(pool) == 0 {
+				pool = game.TierContentsForPack(cx.v.Pack, cx.v.Round)
+			}
+			if len(pool) > 0 {
+				rc := pool[rand.IntN(len(pool))]
+				rc.ID = cx.nextSimID()
+				deck = append(deck, rc)
+			}
+		case game.ActionSetAside:
+			// Golden pack (Avocado): the just-bought token is set aside, not
+			// kept in the deck being scored.
+			if i := slices.IndexFunc(deck, func(d game.Card) bool { return d.ID == c.ID }); i >= 0 {
+				deck = slices.Delete(deck, i, i+1)
+			}
 		}
 	}
 	return deck
 }
 
+// countShopFaintPets counts pets in the shop row with a Faint effect (mirrors
+// the engine's Opossum payout).
+func countShopFaintPets(row []game.Card) int {
+	n := 0
+	for _, c := range row {
+		if c.ID == "" || !c.IsPet() {
+			continue
+		}
+		for _, e := range c.Effects {
+			if e.Trigger == game.TriggerFaint {
+				n++
+				break
+			}
+		}
+	}
+	return n
+}
+
 func (cx *ctx) simApple() game.Card {
 	return game.Card{
 		ID:        cx.nextSimID(),
@@ -133,6 +195,25 @@ func (b *Bot) decideShop(v *game.View, mem *Memory) *Action {
 		}
 	}
 
+	// Golden pack: buying by discarding an Avocado yields the same deck as a
+	// coin buy, so it's only preferred when coins are scarce — a small negative
+	// bias keeps the token in reserve otherwise.
+	if cx.me.Avocados > 0 {
+		for i, c := range v.ShopRow {
+			if c.ID == "" {
+				continue
+			}
+			nd := append(slices.Clone(deck), c)
+			nd = cx.applyTemplateShopEffects(nd, c, game.TriggerBuy)
+			nd = cx.previewSellDown(nd)
+			cands = append(cands, candidate{
+				act:   &Action{Type: "buyAvocado", Row: i},
+				decks: [][]game.Card{nd},
+				bias:  -0.05,
+			})
+		}
+	}
+
 	// Sell candidates: the worst 1, 2, or 3 keepers. Selling is free and
 	// takes any number of cards, so bulk-dumping junk before a battle is one
 	// action. Temporary cards are excluded — selling an apple for an apple
@@ -201,7 +282,7 @@ func (b *Bot) decideShop(v *game.View, mem *Memory) *Action {
 			}
 			pool := cx.unseenPool(v.Round + 1)
 			if len(pool) == 0 {
-				pool = game.TierContents(v.Round + 1)
+				pool = game.TierContentsForPack(v.Pack, v.Round+1)
 			}
 			var decks [][]game.Card
 			for range 3 {