/**
 * Six Flags live wait-times scraper — Fast Lane data.
 *
 * API: https://d18car1k0ff81h.cloudfront.net/wait-times/park/{apiId}
 * Sibling of the operating-hours endpoint in sixflags.ts. Exposes both a
 * regular and a Fast Lane wait per ride. We only consume the Fast Lane side;
 * regular waits + open status keep coming from Queue-Times.
 *
 * The response has no isOpen field, so Fast Lane numbers are joined onto the
 * Queue-Times ride list by name (see lookupFastLane) and gated on the
 * Queue-Times open status by the caller.
 */

import { normalizeForMatch } from "../coaster-match";

const WAIT_TIMES_BASE = "https://d18car1k0ff81h.cloudfront.net/wait-times/park";

// Conjunctions that join two ride names rather than extend one subtitle —
// kept in sync with coaster-match.ts so the prefix match stays symmetric.
const CONJUNCTIONS = new Set(["y", "and", "&", "with", "de", "del", "e", "et"]);

const HEADERS = {
  "User-Agent":
    "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 " +
    "(KHTML, like Gecko) Chrome/124.0.0.0 Safari/537.36",
  Accept: "application/json",
  "Accept-Language": "en-US,en;q=0.9",
  Referer: "https://www.sixflags.com/",
};

interface WTWaittime {
  createdDateTime: string; // "" when no data
  waitTime: number;
}

interface WTRideDetail {
  id: number;
  name: string;
  isFastLane: boolean;
  regularWaittime?: WTWaittime;
  fastlaneWaittime?: WTWaittime;
  fimsId: string;
}

interface WTVenue {
  venueId: number;
  venueName: string;
  details?: WTRideDetail[];
}

export interface WTResponse {
  parkId?: number;
  parkName?: string;
  venues?: WTVenue[];
}

interface FastLaneEntry {
  norm: string;
  compact: string;
  isFastLane: boolean;
  /** Current regular wait in minutes from Six Flags; null when the endpoint has no data. */
  regularMinutes: number | null;
  /** Current Fast Lane wait in minutes; null when the endpoint has no data. */
  fastLaneMinutes: number | null;
}

export interface FastLaneResult {
  entries: FastLaneEntry[];
  /** ISO timestamp of when we fetched the data. */
  fetchedAt: string;
}

/**
 * Parse a raw /wait-times response into Fast Lane entries. Pure and
 * network-free so it can be unit tested. Returns null when no ride rows
 * are present.
 */
export function parseWaitTimes(json: WTResponse): FastLaneResult | null {
  const entries: FastLaneEntry[] = [];
  for (const venue of (json.venues ?? []).filter((v) => v.venueName === "Rides")) {
    for (const d of venue.details ?? []) {
      if (!d.name) continue;
      const norm = normalizeForMatch(d.name);
      entries.push({
        norm,
        compact: norm.replace(/\s/g, ""),
        isFastLane: Boolean(d.isFastLane),
        regularMinutes: d.regularWaittime?.createdDateTime
          ? d.regularWaittime.waitTime
          : null,
        fastLaneMinutes: d.fastlaneWaittime?.createdDateTime
          ? d.fastlaneWaittime.waitTime
          : null,
      });
    }
  }

  if (entries.length === 0) return null;

  return { entries, fetchedAt: new Date().toISOString() };
}

/**
 * Fetch Fast Lane wait times for a park. Returns null on any failure
 * (network/parse/timeout) or when the response carries no rides — same
 * contract as fetchLiveRides.
 *
 * Pass revalidate (seconds) to control Next.js ISR cache lifetime.
 */
export async function fetchFastLaneWaits(
  apiId: number,
  revalidate = 300,
): Promise<FastLaneResult | null> {
  const url = `${WAIT_TIMES_BASE}/${apiId}`;
  try {
    const res = await fetch(url, {
      headers: HEADERS,
      next: { revalidate },
      signal: AbortSignal.timeout(10_000),
    } as RequestInit & { next: { revalidate: number } });

    if (!res.ok) return null;

    return parseWaitTimes((await res.json()) as WTResponse);
  } catch {
    return null;
  }
}

/**
 * Find the Six Flags wait-times row for a ride by name. Mirrors the
 * isCoasterMatch strategy (exact normalized → compact ≥5 → prefix ≥5 with
 * conjunction guard) so Queue-Times and Six Flags name conventions line up.
 *
 * Returns both the regular and Fast Lane wait when a match exists, or null
 * when no ride matches. (Function name is historical — it originally only
 * exposed Fast Lane data.)
 */
export function lookupFastLane(
  rideName: string,
  result: FastLaneResult,
): { hasFastLane: boolean; fastLaneMinutes: number | null; regularMinutes: number | null } | null {
  const norm = normalizeForMatch(rideName);
  const compact = norm.replace(/\s/g, "");

  let match: FastLaneEntry | undefined = result.entries.find((e) => e.norm === norm);

  if (!match) {
    for (const e of result.entries) {
      // Compact comparison
      if (compact.length >= 5 && e.compact === compact) {
        match = e;
        break;
      }
      // Prefix comparison
      const shorter = norm.length <= e.norm.length ? norm : e.norm;
      const longer = norm.length <= e.norm.length ? e.norm : norm;
      if (shorter.length >= 5 && longer.startsWith(shorter)) {
        const nextWord = longer.slice(shorter.length).trim().split(" ")[0];
        if (!CONJUNCTIONS.has(nextWord)) {
          match = e;
          break;
        }
      }
    }
  }

  if (!match) return null;
  return {
    hasFastLane: match.isFastLane,
    fastLaneMinutes: match.fastLaneMinutes,
    regularMinutes: match.regularMinutes,
  };
}