/// <reference types="spotify-api" />
import "dotenv/config";
import { Logger } from "../Logger";
import { SongItem } from "../../types/Track";

const SPOTIFY_CLIENTID = process.env.SPOTIFY_CLIENTID?.trim() ?? "";
const SPOTIFY_SECRET = process.env.SPOTIFY_SECRET?.trim() ?? "";

const SPOTIFY_TOKEN_URL = "https://accounts.spotify.com/api/token";
const SPOTIFY_API_URL = "https://api.spotify.com/v1";
const TOKENR_URL = "http://192.168.10.5:8075/api/token";

const searchCache = new Map<string, string>();

type TOKENER_RESPONSE = {
  clientId: string;
  accessToken: string;
  accessTokenExpirationTimestampMs: number;
  isAnonymous: boolean;
  _notes: string;
};

export const Spotify = {
  _token: {
    cached: "",
    expiresAt: 0,
  },

  async getTokenByTokener(): Promise<string | null> {
    if (this._token.cached && Date.now() < this._token.expiresAt) return this._token.cached;
    try {
      const response = await fetch(TOKENR_URL);
      if (!response.ok) throw new Error(`토크너 서버 응답 에러: ${response.status}`);
      const jsonData = await response.json() as TOKENER_RESPONSE;
      this._token.cached = jsonData.accessToken;
      this._token.expiresAt = jsonData.accessTokenExpirationTimestampMs;
      return jsonData.accessToken;
    } catch (err) {
      Logger.error(`토크너 접근 실패: ${err}`);
      return null;
    }
  },

  async getToken(): Promise<string | null> {
    try {
      const response = await fetch(SPOTIFY_TOKEN_URL, {
        method: "POST",
        headers: {
          "Content-Type": "application/x-www-form-urlencoded",
        },
        body: new URLSearchParams({
          grant_type: "client_credentials",
          client_id: SPOTIFY_CLIENTID,
          client_secret: SPOTIFY_SECRET,
        }),
      });

      const textData = await response.text();

      if (!response.ok) {
        Logger.error(`스포티파이 정식 토큰 발급 에러 (${response.status}): ${textData}`);
        return null;
      }

      const jsonData = JSON.parse(textData);
      
      this._token.cached = jsonData.access_token;
      // expires_in은 초(초당 1000ms) 단위입니다. 만료 1분 전(60000ms)에 미리 갱신되게 세팅!
      this._token.expiresAt = Date.now() + (jsonData.expires_in * 1000) - 60000;

      Logger.info("🟢 [Spotify] 공식 API 키로 정식 토큰 발급 완료!");
      return jsonData.access_token;
    } catch (err) {
      Logger.error(`스포티파이 토큰 요청 실패: ${err}`);
      return null;
    }
  },

  async getSearchFull(query: string): Promise<SongItem[]> {
    try {
      const token = await this.getToken();
      if (!token) return [];

      const response = await fetch(
        `${SPOTIFY_API_URL}/search?q=${encodeURIComponent(query)}&type=track&market=KR&limit=1`,
        {
          headers: {
            Authorization: `Bearer ${token}`,
            "Accept-Language": "ko-KR,ko;q=0.9,en-US;q=0.8,en;q=0.7",
            "user-agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/146.0.0.0 Safari/537.36",
          },
        },
      );

      const textData = await response.text();

      if (!response.ok) {
        if (response.status === 429) {
          Logger.warn("⚠️ 스포티파이 요청 제한(Rate Limit)에 걸렸습니다.");
        } else {
          Logger.error(`스포티파이 API 에러 (${response.status}): ${textData}`);
        }
        return [];
      }

      const data = JSON.parse(textData) as SpotifyApi.TrackSearchResponse;

      if (!data.tracks || data.tracks.items.length === 0) return [];

      return data.tracks.items.map((track) => ({
        videoId: track.id,
        title: track.name,
        artist: track.artists.map(artist => artist.name).join(", "),
        duration: track.duration_ms,
        thumbnail: track.album.images[2]?.url,
      }));
    } catch (err) {
      Logger.error(`스포티파이 검색 실패: ${err}`);
      return [];
    }
  },
  async getSearchUrl(query: string): Promise<string | null> {
    const lowerQuery = query.toLocaleLowerCase().trim();
    if (searchCache.has(lowerQuery)) return searchCache.get(lowerQuery) ?? null;
    const track = (await this.getSearchFull(query) ?? [])?.[0];
    const url = track?.videoId ? `https://open.spotify.com/track/${track.videoId}` : null;
    if (url) searchCache.set(lowerQuery, url);
    return url;
  }
}