import * as http from 'http';

export const getFileContents: (product?: string) => Promise<Buffer> = (product: string = 'assets_swtor_de_de') => new Promise((resolve, reject) => {
  //Generate URL
  const url = `http://cdn-patch.swtor.com/patch/${product}/${product}_-1to0.solidpkg`;
  const path = `/patch/${product}/${product}_-1to0.solidpkg`;
  const fileName = url.substr(url.lastIndexOf('/') + 1);

  const request = http.request({
    family: 4,
    host: 'cdn-patch.swtor.com',
    path,
  }, (response) => {
    if (response.statusCode !== 200) {
      return reject(`Expected status code 200 but received ${response.statusCode}`);
    }
    const headerLength = Number(response.headers['content-length']);

    const chunkList: Buffer[] = [];
    let totalLength = 0;
    response.on('data', (chunk: Buffer) => {
      chunkList.push(chunk);
      totalLength += chunk.length;
    });
    response.on('end', () => {
      if (totalLength !== headerLength) {
        return reject(`Expected length ${headerLength} but received ${totalLength}`);
      }
      const fileContents = Buffer.concat(chunkList, totalLength);
      resolve(fileContents);
    });
  });

  request.on('error', (e) => {
    reject(e);
  });
  request.end();
});

getFileContents();