import { VideoList } from './datatypes/VideoList';
import { VideoOnDemandIndex } from './datatypes/VideoOnDemandIdentifier';

const upstreamURL = process.env.UPSTREAM_URL;
const upstreamDirectURL = process.env.UPSTREAM_DIRECT_URL || upstreamURL;
// const apiURL = process.env.API_URL || `${upstreamURL}/api`;
const apiDirectURL = process.env.API_DIRECT_URL || `${upstreamDirectURL}/api`;

export class HTTPError extends Error {
  response: Response;

  data: any;

  constructor(response: Response, data: any) {
    super(`HTTP server responded with error: ${response.statusText}`);

    this.response = response;
    this.data = data;
  }
}

export async function fetchJson(
  input: RequestInfo,
  init?: RequestInit,
) {
  try {
    const response = await fetch(input, init);

    // if the server replies, there's always some data in json
    // if there's a network error, it will throw at the previous line
    const data = await response.json();

    if (response.ok) {
      return data;
    }

    throw new HTTPError(response, data);
  } catch (error) {
    if (!error.data) {
      error.data = { message: error.message };
    }
    throw error;
  }
}

async function getDirect(relativeURL: string) {
  return fetchJson(`${apiDirectURL}/${relativeURL}`);
}

// async function get(relativeURL: any) {
//   return fetchJson(`${apiURL}/${relativeURL}`);
// }

export async function getIndex(): Promise<VideoOnDemandIndex> {
  return getDirect('index.json');
}

export async function getVideos(id: string): Promise<VideoList> {
  return getDirect(`videos/${id}.json`);
}

export function getDownloadURL(id: string, fileName: string): string {
  return [upstreamURL, encodeURIComponent(id), encodeURIComponent(fileName)]
    .join('/');
}

export function submitPreferences(data: {
  enableDark?: boolean,
  locale?: string,
  volume?: number,
}) {
  const formData = new URLSearchParams();
  if (data.enableDark !== undefined && data.enableDark !== null) {
    formData.append('enableDark', data.enableDark.toString());
  }
  if (data.locale !== undefined && data.locale !== null) {
    formData.append('locale', data.locale);
  }
  if (data.volume !== undefined && data.volume !== null) {
    formData.append('volume', data.volume.toString());
  }

  fetchJson('/api/changePreferences', {
    method: 'POST',
    headers: {
      'Content-Type': 'application/x-www-form-urlencoded',
    },
    body: formData,
  });
}