/**
 * @file Enlightenment service handling eligibility checks and post-enlightenment state building.
 * @copyright nhcarrigan
 * @license Naomi's Public License
 * @author Naomi Carrigan
 */
/* eslint-disable stylistic/max-len -- Service logic requires long lines */
import { defaultEnlightenmentUpgrades } from "../data/goddessEnlightenmentUpgrades.js";
import { initialGoddessState } from "../data/initialState.js";
import type { EnlightenmentData, GameState } from "@elysium/types";

/**
 * ID of the final goddess boss — must be defeated to unlock Enlightenment.
 */
const finalGoddessBossId = "divine_heart_sovereign";

const getCategoryMultiplier = (
  purchasedIds: Array<string>,
  category: string,
): number => {
  return defaultEnlightenmentUpgrades.filter((upgrade) => {
    return upgrade.category === category && purchasedIds.includes(upgrade.id);
  }).reduce((mult, upgrade) => {
    return mult * upgrade.multiplier;
  }, 1);
};

/**
 * Computes all five stardust multipliers from the purchased enlightenment upgrade IDs.
 * @param purchasedUpgradeIds - The array of purchased enlightenment upgrade IDs.
 * @returns An object containing all five stardust multiplier values.
 */
const computeEnlightenmentMultipliers = (
  purchasedUpgradeIds: Array<string>,
): Omit<EnlightenmentData, "count" | "stardust" | "purchasedUpgradeIds"> => {
  return {
    stardustCombatMultiplier:                getCategoryMultiplier(purchasedUpgradeIds, "combat"),
    stardustConsecrationDivinityMultiplier:  getCategoryMultiplier(purchasedUpgradeIds, "consecration_divinity"),
    stardustConsecrationThresholdMultiplier: getCategoryMultiplier(purchasedUpgradeIds, "consecration_threshold"),
    stardustMetaMultiplier:                  getCategoryMultiplier(purchasedUpgradeIds, "stardust_meta"),
    stardustPrayersMultiplier:               getCategoryMultiplier(purchasedUpgradeIds, "prayers"),
  };
};

/**
 * Returns true when the player is eligible for Enlightenment:
 * they must have defeated the final goddess boss at least once.
 * @param state - The current game state.
 * @returns Whether the player is eligible for Enlightenment.
 */
const isEligibleForEnlightenment = (state: GameState): boolean => {
  // eslint-disable-next-line capitalized-comments -- v8 ignore
  /* v8 ignore next 3 -- @preserve */
  if (state.goddess === undefined) {
    return false;
  }
  return state.goddess.bosses.some((boss) => {
    return boss.id === finalGoddessBossId && boss.status === "defeated";
  });
};

/**
 * Calculates the stardust yield from an Enlightenment.
 * Formula: MAX(1, FLOOR(SQRT(consecrationCount) * metaMultiplier)).
 * @param consecrationCount - The number of consecrations completed before this Enlightenment.
 * @param metaMultiplier - Multiplier from prior enlightenment upgrades applied to stardust yield.
 * @returns The stardust earned.
 */
const calculateStardustYield = (
  consecrationCount: number,
  metaMultiplier: number,
): number => {
  return Math.max(1, Math.floor(Math.sqrt(consecrationCount) * metaMultiplier));
};

/**
 * Builds the updated goddess state after an Enlightenment — a full goddess reset.
 * Wipes everything including consecration, preserving only equipment, achievements, and enlightenment data.
 * @param state - The current game state before enlightenment.
 * @returns The stardust earned and the updated goddess state.
 */
const buildPostEnlightenmentState = (
  state: GameState,
): { stardustEarned: number; updatedGoddess: NonNullable<GameState["goddess"]> } => {
  // eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- Caller must ensure goddess exists
  const goddess = state.goddess as NonNullable<GameState["goddess"]>;

  const metaMultiplier = goddess.enlightenment.stardustMetaMultiplier;
  const stardustEarned = calculateStardustYield(
    goddess.consecration.count,
    metaMultiplier,
  );

  const updatedCount = goddess.enlightenment.count + 1;
  const updatedStardust = goddess.enlightenment.stardust + stardustEarned;
  const updatedPurchasedIds = goddess.enlightenment.purchasedUpgradeIds;
  const updatedMultipliers = computeEnlightenmentMultipliers(updatedPurchasedIds);

  const updatedEnlightenment: EnlightenmentData = {
    count:               updatedCount,
    purchasedUpgradeIds: updatedPurchasedIds,
    stardust:            updatedStardust,
    ...updatedMultipliers,
  };

  const freshGoddess = initialGoddessState();

  const updatedGoddess: NonNullable<GameState["goddess"]> = {
    ...freshGoddess,
    achievements: goddess.achievements,
    bosses:       freshGoddess.bosses.map((b) => {
      const existing = goddess.bosses.find((gb) => {
        return gb.id === b.id;
      });
      return {
        ...b,
        bountyDivinityClaimed: existing?.bountyDivinityClaimed ?? false,
      };
    }),
    enlightenment:           updatedEnlightenment,
    equipment:               goddess.equipment,
    lastTickAt:              Date.now(),
    lifetimeBossesDefeated:  goddess.lifetimeBossesDefeated,
    lifetimePrayersEarned:   goddess.lifetimePrayersEarned,
    lifetimeQuestsCompleted: goddess.lifetimeQuestsCompleted,
    totalPrayersEarned:      0,
  };

  return { stardustEarned, updatedGoddess };
};

export {
  buildPostEnlightenmentState,
  calculateStardustYield,
  computeEnlightenmentMultipliers,
  isEligibleForEnlightenment,
};