/**
 * @file Awakening service handling eligibility checks and post-awakening state building.
 * @copyright nhcarrigan
 * @license Naomi's Public License
 * @author Naomi Carrigan
 */

/* eslint-disable stylistic/max-len -- Service logic requires long lines */
import { initialVampireState } from "../data/initialState.js";
import { defaultVampireAwakeningUpgrades } from "../data/vampireAwakeningUpgrades.js";
import type { AwakeningData, GameState } from "@elysium/types";

/**
 * The ID of the final vampire boss whose defeat triggers eligibility for awakening.
 */
const finalVampireBossId = "eternal_darkness";

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

/**
 * Computes all five soul shard multipliers from the purchased awakening upgrade IDs.
 * @param purchasedUpgradeIds - The array of purchased awakening upgrade IDs.
 * @returns An object containing all five soul shard multiplier values.
 */
const computeAwakeningMultipliers = (
  purchasedUpgradeIds: Array<string>,
): Omit<AwakeningData, "count" | "soulShards" | "purchasedUpgradeIds"> => {
  return {
    soulShardsBloodMultiplier:           getCategoryMultiplier(purchasedUpgradeIds, "blood"),
    soulShardsCombatMultiplier:          getCategoryMultiplier(purchasedUpgradeIds, "combat"),
    soulShardsMetaMultiplier:            getCategoryMultiplier(purchasedUpgradeIds, "soulshards_meta"),
    soulShardsSiringIchorMultiplier:     getCategoryMultiplier(purchasedUpgradeIds, "siring_ichor"),
    soulShardsSiringThresholdMultiplier: getCategoryMultiplier(purchasedUpgradeIds, "siring_threshold"),
  };
};

/**
 * Returns true if the player is eligible to awaken:
 * the final vampire boss must have been defeated.
 * @param state - The current game state.
 * @returns Whether the player is eligible for awakening.
 */
const isEligibleForAwakening = (state: GameState): boolean => {
  // eslint-disable-next-line capitalized-comments -- v8 ignore
  /* v8 ignore next 3 -- @preserve */
  if (state.vampire === undefined) {
    return false;
  }
  return state.vampire.bosses.some((boss) => {
    return boss.id === finalVampireBossId && boss.status === "defeated";
  });
};

/**
 * Calculates the soul shards yield from an awakening.
 * Formula: MAX(1, FLOOR(SQRT(siringCount) * metaMultiplier)).
 * @param siringCount - The number of sirings completed.
 * @param metaMultiplier - Multiplier from soul shard meta upgrades applied to yield.
 * @returns The soul shards earned.
 */
const calculateSoulShardsYield = (
  siringCount: number,
  metaMultiplier: number,
): number => {
  return Math.max(1, Math.floor(Math.sqrt(siringCount) * metaMultiplier));
};

/**
 * Builds the updated vampire state after an awakening reset.
 * Resets the current run including siring data (bosses, quests, thralls, upgrades, zones, siring data).
 * Preserves: equipment, achievements, awakening data (updated), eternal sovereignty, lifetime stats.
 * @param state - The current game state before awakening.
 * @returns The soul shards earned and the updated vampire state.
 */
const buildPostAwakeningState = (
  state: GameState,
): { soulShardsEarned: number; updatedVampire: NonNullable<GameState["vampire"]> } => {
  /* eslint-disable-next-line @typescript-eslint/consistent-type-assertions -- Caller must ensure vampire exists */
  const vampire = state.vampire as NonNullable<GameState["vampire"]>;

  const metaMultiplier = vampire.awakening.soulShardsMetaMultiplier;
  const soulShardsEarned = calculateSoulShardsYield(vampire.siring.count, metaMultiplier);

  const updatedCount = vampire.awakening.count + 1;
  const updatedSoulShards = vampire.awakening.soulShards + soulShardsEarned;
  const updatedPurchasedIds = vampire.awakening.purchasedUpgradeIds;
  const updatedMultipliers = computeAwakeningMultipliers(updatedPurchasedIds);

  const updatedAwakening: AwakeningData = {
    count:               updatedCount,
    purchasedUpgradeIds: updatedPurchasedIds,
    soulShards:          updatedSoulShards,
    ...updatedMultipliers,
  };

  const freshVampire = initialVampireState();

  const updatedVampire: NonNullable<GameState["vampire"]> = {
    ...freshVampire,
    achievements: vampire.achievements,
    awakening:    updatedAwakening,
    bosses:       freshVampire.bosses.map((b) => {
      const existing = vampire.bosses.find((vb) => {
        return vb.id === b.id;
      });
      return {
        ...b,
        bountyIchorClaimed: existing?.bountyIchorClaimed ?? false,
      };
    }),
    equipment:               vampire.equipment,
    eternalSovereignty:      vampire.eternalSovereignty,
    lastTickAt:              Date.now(),
    lifetimeBloodEarned:     vampire.lifetimeBloodEarned,
    lifetimeBossesDefeated:  vampire.lifetimeBossesDefeated,
    lifetimeQuestsCompleted: vampire.lifetimeQuestsCompleted,
    totalBloodEarned:        0,
  };

  return { soulShardsEarned, updatedVampire };
};

export {
  buildPostAwakeningState,
  calculateSoulShardsYield,
  computeAwakeningMultipliers,
  isEligibleForAwakening,
};