big version with draft order and weather cards

src/rules-initiative.ts

@@ -0,0 +1,51 @@
+import type { GameState, InitiativeDraftState, PlayerId } from "./types";
+
+export function getSeatBonuses(state: GameState) {
+  const graceRounds = Math.max(0, Math.floor(state.config.columns / state.players.length) - state.players.length);
+  const firstSeatBonus = state.round <= graceRounds ? 0 : 1;
+
+  return Array.from({ length: state.players.length }, (_, index) => (index === 0 ? firstSeatBonus : 0));
+}
+
+export function getRotatingBiddingOrder(state: GameState) {
+  const start = (state.initiativeAnchorPlayerId + state.round - 1) % state.players.length;
+  return Array.from({ length: state.players.length }, (_, index) => (start + index) % state.players.length);
+}
+
+export function getLowestGrowthBiddingOrder(state: GameState) {
+  const orderRank = new Map<PlayerId, number>(state.turnOrder.map((playerId, index) => [playerId, index]));
+
+  return [...state.players]
+    .sort((left, right) => {
+      if (left.lifetimeGrowthIncome !== right.lifetimeGrowthIncome) {
+        return left.lifetimeGrowthIncome - right.lifetimeGrowthIncome;
+      }
+
+      const leftRank = orderRank.get(left.id) ?? left.id;
+      const rightRank = orderRank.get(right.id) ?? right.id;
+      if (leftRank !== rightRank) {
+        return leftRank - rightRank;
+      }
+
+      return left.id - right.id;
+    })
+    .map((player) => player.id);
+}
+
+export function createInitiativeDraft(state: GameState): InitiativeDraftState {
+  const biddingOrder = state.config.biddingOrderRule === "lowest_growth_income"
+    ? getLowestGrowthBiddingOrder(state)
+    : getRotatingBiddingOrder(state);
+
+  return {
+    biddingOrder,
+    biddingIndex: 0,
+    seatAssignments: Array.from({ length: state.players.length }, () => null),
+    seatBonuses: getSeatBonuses(state),
+  };
+}
+
+export function getSeatNumberForPlayer(draft: InitiativeDraftState, playerId: PlayerId) {
+  const seatIndex = draft.seatAssignments.findIndex((assignedPlayerId) => assignedPlayerId === playerId);
+  return seatIndex === -1 ? null : seatIndex + 1;
+}