import type { ApotheosisData, GameState } from "@elysium/types";
import { INITIAL_GAME_STATE } from "../data/initialState.js";
import { DEFAULT_TRANSCENDENCE_UPGRADES } from "../data/transcendenceUpgrades.js";

/** Total number of echo upgrades — all must be purchased to unlock Apotheosis */
const TOTAL_ECHO_UPGRADES = DEFAULT_TRANSCENDENCE_UPGRADES.length;

/**
 * Returns true when the player is eligible to achieve Apotheosis:
 * all Transcendence echo upgrades must be purchased.
 */
export const isEligibleForApotheosis = (state: GameState): boolean => {
  const purchasedIds = state.transcendence?.purchasedUpgradeIds ?? [];
  return purchasedIds.length >= TOTAL_ECHO_UPGRADES &&
    DEFAULT_TRANSCENDENCE_UPGRADES.every((u) => purchasedIds.includes(u.id));
};

/**
 * Builds the new game state after Apotheosis — the ultimate nuclear reset.
 * Wipes absolutely everything including prestige and transcendence.
 * Only codex lore entries and the apotheosis count itself are preserved.
 */
export const buildPostApotheosisState = (
  currentState: GameState,
  characterName: string,
): { newState: GameState; newApotheosisData: ApotheosisData } => {
  const newCount = (currentState.apotheosis?.count ?? 0) + 1;
  const newApotheosisData: ApotheosisData = { count: newCount };

  const freshState = INITIAL_GAME_STATE(currentState.player, characterName);
  const newState: GameState = {
    ...freshState,
    lastTickAt: Date.now(),
    // Codex lore persists through all resets — players keep their discovered entries
    ...(currentState.codex ? { codex: currentState.codex } : {}),
    // Apotheosis data is eternal — never wiped by any reset
    apotheosis: newApotheosisData,
  };

  return { newState, newApotheosisData };
};