import { NUM_POKEMON } from "../rom/profile";
import { NICKNAME_PATTERN, PARTY_LENGTH, type PartyMon } from "./pokemon";

/** NUM_HOF_TEAMS: the teams sHallOfFame keeps; HOF_MASTER_COUNT: where
 * wHallOfFameCount stops (constants/misc_constants.asm). */
export const NUM_HOF_TEAMS = 30;
export const HOF_MASTER_COUNT = 200;

/** HOF_MON_LENGTH: only the fields GetHallOfFameParty copies. */
export interface HallOfFameMon {
  species: number;
  otId: number;
  dvs: number;
  level: number;
  nickname: string;
}
/** One sHallOfFame entry (HOF_LENGTH): the win it records and the team
 * that won, without its Eggs. */
export interface HallOfFameTeam {
  /** wHallOfFameCount when the team entered, capped at HOF_MASTER_COUNT. */
  win: number;
  mons: HallOfFameMon[];
}
export interface HallOfFameRecords {
  /** wHallOfFameCount: the League wins, up to HOF_MASTER_COUNT. */
  hallOfFameCount: number;
  /** sHallOfFame, newest first. Separate from STATUSFLAGS_HALL_OF_FAME_F. */
  hallOfFameTeams: HallOfFameTeam[];
}

/** GetHallOfFameParty: skip Eggs, copy the six recorded fields, and keep
 * party order. An all-Egg party produces an empty team. */
export function getHallOfFameParty(
  party: readonly PartyMon[],
  win: number,
): HallOfFameTeam {
  return {
    win,
    mons: party
      .filter((mon) => !mon.egg)
      .map(({ species, otId, dvs, level, nickname }) => ({
        species,
        otId,
        dvs,
        level,
        nickname,
      })),
  };
}

/** HallOfFame's capped count increment, then AddHallOfFameEntry: the
 * newest team goes first and the oldest of a full sHallOfFame drops off.
 * The League's ceremony is not ported, so nothing calls this yet; it
 * leaves STATUSFLAGS_HALL_OF_FAME_F (`hallOfFame`) to its caller. */
export function addHallOfFameEntry(
  records: HallOfFameRecords,
  party: readonly PartyMon[],
) {
  records.hallOfFameCount = Math.min(
    HOF_MASTER_COUNT,
    records.hallOfFameCount + 1,
  );
  records.hallOfFameTeams.unshift(
    getHallOfFameParty(party, records.hallOfFameCount),
  );
  records.hallOfFameTeams.length = Math.min(
    NUM_HOF_TEAMS,
    records.hallOfFameTeams.length,
  );
}

/** Structural records validation; no stats, party ownership or current
 * species are required of a historical entry. */
export function validHallOfFame(
  count: unknown,
  value: unknown,
): value is HallOfFameTeam[] {
  const integer = (n: unknown, min: number, max: number): n is number =>
    Number.isInteger(n) && Number(n) >= min && Number(n) <= max;
  if (
    !integer(count, 0, HOF_MASTER_COUNT) ||
    !Array.isArray(value) ||
    value.length > NUM_HOF_TEAMS
  )
    return false;
  if ((count === 0) !== (value.length === 0) || value.length > count)
    return false;
  return value.every(
    (team, index) =>
      team !== null &&
      typeof team === "object" &&
      integer(team.win, 1, count) &&
      (index === 0 ? team.win === count : team.win <= value[index - 1].win) &&
      Array.isArray(team.mons) &&
      team.mons.length <= PARTY_LENGTH &&
      team.mons.every(
        (mon: HallOfFameMon) =>
          mon !== null &&
          typeof mon === "object" &&
          integer(mon.species, 1, NUM_POKEMON) &&
          integer(mon.otId, 0, 65535) &&
          integer(mon.dvs, 0, 65535) &&
          integer(mon.level, 1, 100) &&
          typeof mon.nickname === "string" &&
          NICKNAME_PATTERN.test(mon.nickname),
      ),
  );
}