// The Death Creation Step: the one place minions leave play.
//
// Damage and destroy effects only mark a minion (0 or less Health, or pending
// destroy). It stays in play, and keeps triggering, until the outermost Phase
// ends. Then this step removes every marked minion at once.

import type { Event } from "./event";
import type { World } from "./world";

/**
 * Remove every mortally wounded or pending-destroy minion from play, simultaneously.
 * Returns their Death Events in order of play; empty if nothing died.
 */
export function deathCreationStep(world: World): Event[] {
  const dying = world.minionsInPlay().filter((id) => world.isDoomed(id));
  // Every position is read before anything moves: removal is simultaneous, and each
  // Death Event remembers where its minion stood when the step began.
  const deaths = dying.map((id) => ({ type: "Destroyed" as const, id, position: world.boardIndex(id)! }));
  for (const { id, position } of deaths) world.kill(id, position);
  return deaths;
}