"use strict";

const arch = require('arch');

const la = require('lazy-ass');

const is = require('check-more-types');

const os = require('os');

const url = require('url');

const path = require('path');

const debug = require('debug')('cypress:cli');

const request = require('@cypress/request');

const Promise = require('bluebird');

const requestProgress = require('request-progress');

const {
  stripIndent
} = require('common-tags');

const {
  throwFormErrorText,
  errors
} = require('../errors');

const fs = require('../fs');

const util = require('../util');

const defaultBaseUrl = 'https://download.cypress.io/';

const getProxyUrl = () => {
  return process.env.HTTPS_PROXY || process.env.https_proxy || process.env.npm_config_https_proxy || process.env.HTTP_PROXY || process.env.http_proxy || process.env.npm_config_proxy || null;
};

const getRealOsArch = () => {
  // os.arch() returns the arch for which this node was compiled
  // we want the operating system's arch instead: x64 or x86
  const osArch = arch();

  if (osArch === 'x86') {
    // match process.platform output
    return 'ia32';
  }

  return osArch;
};

const getBaseUrl = () => {
  if (util.getEnv('CYPRESS_DOWNLOAD_MIRROR')) {
    let baseUrl = util.getEnv('CYPRESS_DOWNLOAD_MIRROR');

    if (!baseUrl.endsWith('/')) {
      baseUrl += '/';
    }

    return baseUrl;
  }

  return defaultBaseUrl;
};

const getCA = () => {
  return new Promise(resolve => {
    if (!util.getEnv('CYPRESS_DOWNLOAD_USE_CA')) {
      resolve();
    }

    if (process.env.npm_config_ca) {
      resolve(process.env.npm_config_ca);
    } else if (process.env.npm_config_cafile) {
      fs.readFile(process.env.npm_config_cafile, 'utf8').then(cafileContent => {
        resolve(cafileContent);
      }).catch(() => {
        resolve();
      });
    } else {
      resolve();
    }
  });
};

const prepend = urlPath => {
  const endpoint = url.resolve(getBaseUrl(), urlPath);
  const platform = os.platform();
  const arch = getRealOsArch();
  return `${endpoint}?platform=${platform}&arch=${arch}`;
};

const getUrl = version => {
  if (is.url(version)) {
    debug('version is already an url', version);
    return version;
  }

  return version ? prepend(`desktop/${version}`) : prepend('desktop');
};

const statusMessage = err => {
  return err.statusCode ? [err.statusCode, err.statusMessage].join(' - ') : err.toString();
};

const prettyDownloadErr = (err, version) => {
  const msg = stripIndent`
    URL: ${getUrl(version)}
    ${statusMessage(err)}
  `;
  debug(msg);
  return throwFormErrorText(errors.failedDownload)(msg);
};
/**
 * Checks checksum and file size for the given file. Allows both
 * values or just one of them to be checked.
 */


const verifyDownloadedFile = (filename, expectedSize, expectedChecksum) => {
  if (expectedSize && expectedChecksum) {
    debug('verifying checksum and file size');
    return Promise.join(util.getFileChecksum(filename), util.getFileSize(filename), (checksum, filesize) => {
      if (checksum === expectedChecksum && filesize === expectedSize) {
        debug('downloaded file has the expected checksum and size ✅');
        return;
      }

      debug('raising error: checksum or file size mismatch');
      const text = stripIndent`
          Corrupted download

          Expected downloaded file to have checksum: ${expectedChecksum}
          Computed checksum: ${checksum}

          Expected downloaded file to have size: ${expectedSize}
          Computed size: ${filesize}
        `;
      debug(text);
      throw new Error(text);
    });
  }

  if (expectedChecksum) {
    debug('only checking expected file checksum %d', expectedChecksum);
    return util.getFileChecksum(filename).then(checksum => {
      if (checksum === expectedChecksum) {
        debug('downloaded file has the expected checksum ✅');
        return;
      }

      debug('raising error: file checksum mismatch');
      const text = stripIndent`
        Corrupted download

        Expected downloaded file to have checksum: ${expectedChecksum}
        Computed checksum: ${checksum}
      `;
      throw new Error(text);
    });
  }

  if (expectedSize) {
    // maybe we don't have a checksum, but at least CDN returns content length
    // which we can check against the file size
    debug('only checking expected file size %d', expectedSize);
    return util.getFileSize(filename).then(filesize => {
      if (filesize === expectedSize) {
        debug('downloaded file has the expected size ✅');
        return;
      }

      debug('raising error: file size mismatch');
      const text = stripIndent`
          Corrupted download

          Expected downloaded file to have size: ${expectedSize}
          Computed size: ${filesize}
        `;
      throw new Error(text);
    });
  }

  debug('downloaded file lacks checksum or size to verify');
  return Promise.resolve();
}; // downloads from given url
// return an object with
// {filename: ..., downloaded: true}


const downloadFromUrl = ({
  url,
  downloadDestination,
  progress,
  ca
}) => {
  return new Promise((resolve, reject) => {
    const proxy = getProxyUrl();
    debug('Downloading package', {
      url,
      proxy,
      downloadDestination
    });
    let redirectVersion;
    const reqOptions = {
      url,
      proxy,

      followRedirect(response) {
        const version = response.headers['x-version'];
        debug('redirect version:', version);

        if (version) {
          // set the version in options if we have one.
          // this insulates us from potential redirect
          // problems where version would be set to undefined.
          redirectVersion = version;
        } // yes redirect


        return true;
      }

    };

    if (ca) {
      debug('using custom CA details from npm config');
      reqOptions.agentOptions = {
        ca
      };
    }

    const req = request(reqOptions); // closure

    let started = null;
    let expectedSize;
    let expectedChecksum;
    requestProgress(req, {
      throttle: progress.throttle
    }).on('response', response => {
      // we have computed checksum and filesize during test runner binary build
      // and have set it on the S3 object as user meta data, available via
      // these custom headers "x-amz-meta-..."
      // see https://github.com/cypress-io/cypress/pull/4092
      expectedSize = response.headers['x-amz-meta-size'] || response.headers['content-length'];
      expectedChecksum = response.headers['x-amz-meta-checksum'];

      if (expectedChecksum) {
        debug('expected checksum %s', expectedChecksum);
      }

      if (expectedSize) {
        // convert from string (all Amazon custom headers are strings)
        expectedSize = Number(expectedSize);
        debug('expected file size %d', expectedSize);
      } // start counting now once we've gotten
      // response headers


      started = new Date(); // if our status code does not start with 200

      if (!/^2/.test(response.statusCode)) {
        debug('response code %d', response.statusCode);
        const err = new Error(stripIndent`
          Failed downloading the Cypress binary.
          Response code: ${response.statusCode}
          Response message: ${response.statusMessage}
        `);
        reject(err);
      }
    }).on('error', reject).on('progress', state => {
      // total time we've elapsed
      // starting on our first progress notification
      const elapsed = new Date() - started; // request-progress sends a value between 0 and 1

      const percentage = util.convertPercentToPercentage(state.percent);
      const eta = util.calculateEta(percentage, elapsed); // send up our percent and seconds remaining

      progress.onProgress(percentage, util.secsRemaining(eta));
    }) // save this download here
    .pipe(fs.createWriteStream(downloadDestination)).on('finish', () => {
      debug('downloading finished');
      verifyDownloadedFile(downloadDestination, expectedSize, expectedChecksum).then(() => {
        return resolve(redirectVersion);
      }, reject);
    });
  });
};
/**
 * Download Cypress.zip from external url to local file.
 * @param [string] version Could be "3.3.0" or full URL
 * @param [string] downloadDestination Local filename to save as
 */


const start = opts => {
  let {
    version,
    downloadDestination,
    progress
  } = opts;

  if (!downloadDestination) {
    la(is.unemptyString(downloadDestination), 'missing download dir', opts);
  }

  if (!progress) {
    progress = {
      onProgress: () => {
        return {};
      }
    };
  }

  const url = getUrl(version);
  progress.throttle = 100;
  debug('needed Cypress version: %s', version);
  debug('source url %s', url);
  debug(`downloading cypress.zip to "${downloadDestination}"`); // ensure download dir exists

  return fs.ensureDirAsync(path.dirname(downloadDestination)).then(() => {
    return getCA();
  }).then(ca => {
    return downloadFromUrl({
      url,
      downloadDestination,
      progress,
      ca
    });
  }).catch(err => {
    return prettyDownloadErr(err, version);
  });
};

module.exports = {
  start,
  getUrl,
  getProxyUrl,
  getCA
};