'use strict';

import utils from './../utils.js';
import settle from './../core/settle.js';
import buildFullPath from '../core/buildFullPath.js';
import buildURL from './../helpers/buildURL.js';
import {getProxyForUrl} from 'proxy-from-env';
import http from 'http';
import https from 'https';
import followRedirects from 'follow-redirects';
import zlib from 'zlib';
import {VERSION} from '../env/data.js';
import transitionalDefaults from '../defaults/transitional.js';
import AxiosError from '../core/AxiosError.js';
import CanceledError from '../cancel/CanceledError.js';
import platform from '../platform/index.js';
import fromDataURI from '../helpers/fromDataURI.js';
import stream from 'stream';
import AxiosHeaders from '../core/AxiosHeaders.js';
import AxiosTransformStream from '../helpers/AxiosTransformStream.js';
import EventEmitter from 'events';

const zlibOptions = {
  flush: zlib.constants.Z_SYNC_FLUSH,
  finishFlush: zlib.constants.Z_SYNC_FLUSH
};

const brotliOptions = {
  flush: zlib.constants.BROTLI_OPERATION_FLUSH,
  finishFlush: zlib.constants.BROTLI_OPERATION_FLUSH
}

const isBrotliSupported = utils.isFunction(zlib.createBrotliDecompress);

const {http: httpFollow, https: httpsFollow} = followRedirects;

const isHttps = /https:?/;

const supportedProtocols = platform.protocols.map(protocol => {
  return protocol + ':';
});

/**
 * If the proxy or config beforeRedirects functions are defined, call them with the options
 * object.
 *
 * @param {Object<string, any>} options - The options object that was passed to the request.
 *
 * @returns {Object<string, any>}
 */
function dispatchBeforeRedirect(options) {
  if (options.beforeRedirects.proxy) {
    options.beforeRedirects.proxy(options);
  }
  if (options.beforeRedirects.config) {
    options.beforeRedirects.config(options);
  }
}

/**
 * If the proxy or config afterRedirects functions are defined, call them with the options
 *
 * @param {http.ClientRequestArgs} options
 * @param {AxiosProxyConfig} configProxy configuration from Axios options object
 * @param {string} location
 *
 * @returns {http.ClientRequestArgs}
 */
function setProxy(options, configProxy, location) {
  let proxy = configProxy;
  if (!proxy && proxy !== false) {
    const proxyUrl = getProxyForUrl(location);
    if (proxyUrl) {
      proxy = new URL(proxyUrl);
    }
  }
  if (proxy) {
    // Basic proxy authorization
    if (proxy.username) {
      proxy.auth = (proxy.username || '') + ':' + (proxy.password || '');
    }

    if (proxy.auth) {
      // Support proxy auth object form
      if (proxy.auth.username || proxy.auth.password) {
        proxy.auth = (proxy.auth.username || '') + ':' + (proxy.auth.password || '');
      }
      const base64 = Buffer
        .from(proxy.auth, 'utf8')
        .toString('base64');
      options.headers['Proxy-Authorization'] = 'Basic ' + base64;
    }

    options.headers.host = options.hostname + (options.port ? ':' + options.port : '');
    const proxyHost = proxy.hostname || proxy.host;
    options.hostname = proxyHost;
    // Replace 'host' since options is not a URL object
    options.host = proxyHost;
    options.port = proxy.port;
    options.path = location;
    if (proxy.protocol) {
      options.protocol = proxy.protocol.includes(':') ? proxy.protocol : `${proxy.protocol}:`;
    }
  }

  options.beforeRedirects.proxy = function beforeRedirect(redirectOptions) {
    // Configure proxy for redirected request, passing the original config proxy to apply
    // the exact same logic as if the redirected request was performed by axios directly.
    setProxy(redirectOptions, configProxy, redirectOptions.href);
  };
}

const isHttpAdapterSupported = typeof process !== 'undefined' && utils.kindOf(process) === 'process';

/*eslint consistent-return:0*/
export default isHttpAdapterSupported && function httpAdapter(config) {
  return new Promise(function dispatchHttpRequest(resolvePromise, rejectPromise) {
    let data = config.data;
    const responseType = config.responseType;
    const responseEncoding = config.responseEncoding;
    const method = config.method.toUpperCase();
    let isFinished;
    let isDone;
    let rejected = false;
    let req;

    // temporary internal emitter until the AxiosRequest class will be implemented
    const emitter = new EventEmitter();

    function onFinished() {
      if (isFinished) return;
      isFinished = true;

      if (config.cancelToken) {
        config.cancelToken.unsubscribe(abort);
      }

      if (config.signal) {
        config.signal.removeEventListener('abort', abort);
      }

      emitter.removeAllListeners();
    }

    function done(value, isRejected) {
      if (isDone) return;

      isDone = true;

      if (isRejected) {
        rejected = true;
        onFinished();
      }

      isRejected ? rejectPromise(value) : resolvePromise(value);
    }

    const resolve = function resolve(value) {
      done(value);
    };

    const reject = function reject(value) {
      done(value, true);
    };

    function abort(reason) {
      emitter.emit('abort', !reason || reason.type ? new CanceledError(null, config, req) : reason);
    }

    emitter.once('abort', reject);

    if (config.cancelToken || config.signal) {
      config.cancelToken && config.cancelToken.subscribe(abort);
      if (config.signal) {
        config.signal.aborted ? abort() : config.signal.addEventListener('abort', abort);
      }
    }

    // Parse url
    const fullPath = buildFullPath(config.baseURL, config.url);
    const parsed = new URL(fullPath);
    const protocol = parsed.protocol || supportedProtocols[0];

    if (protocol === 'data:') {
      let convertedData;

      if (method !== 'GET') {
        return settle(resolve, reject, {
          status: 405,
          statusText: 'method not allowed',
          headers: {},
          config
        });
      }

      try {
        convertedData = fromDataURI(config.url, responseType === 'blob', {
          Blob: config.env && config.env.Blob
        });
      } catch (err) {
        throw AxiosError.from(err, AxiosError.ERR_BAD_REQUEST, config);
      }

      if (responseType === 'text') {
        convertedData = convertedData.toString(responseEncoding);

        if (!responseEncoding || responseEncoding === 'utf8') {
          data = utils.stripBOM(convertedData);
        }
      } else if (responseType === 'stream') {
        convertedData = stream.Readable.from(convertedData);
      }

      return settle(resolve, reject, {
        data: convertedData,
        status: 200,
        statusText: 'OK',
        headers: new AxiosHeaders(),
        config
      });
    }

    if (supportedProtocols.indexOf(protocol) === -1) {
      return reject(new AxiosError(
        'Unsupported protocol ' + protocol,
        AxiosError.ERR_BAD_REQUEST,
        config
      ));
    }

    const headers = AxiosHeaders.from(config.headers).normalize();

    // Set User-Agent (required by some servers)
    // See https://github.com/axios/axios/issues/69
    // User-Agent is specified; handle case where no UA header is desired
    // Only set header if it hasn't been set in config
    headers.set('User-Agent', 'axios/' + VERSION, false);

    const onDownloadProgress = config.onDownloadProgress;
    const onUploadProgress = config.onUploadProgress;
    const maxRate = config.maxRate;
    let maxUploadRate = undefined;
    let maxDownloadRate = undefined;

    // support for https://www.npmjs.com/package/form-data api
    if (utils.isFormData(data) && utils.isFunction(data.getHeaders)) {
      headers.set(data.getHeaders());
    } else if (data && !utils.isStream(data)) {
      if (Buffer.isBuffer(data)) {
        // Nothing to do...
      } else if (utils.isArrayBuffer(data)) {
        data = Buffer.from(new Uint8Array(data));
      } else if (utils.isString(data)) {
        data = Buffer.from(data, 'utf-8');
      } else {
        return reject(new AxiosError(
          'Data after transformation must be a string, an ArrayBuffer, a Buffer, or a Stream',
          AxiosError.ERR_BAD_REQUEST,
          config
        ));
      }

      // Add Content-Length header if data exists
      headers.set('Content-Length', data.length, false);

      if (config.maxBodyLength > -1 && data.length > config.maxBodyLength) {
        return reject(new AxiosError(
          'Request body larger than maxBodyLength limit',
          AxiosError.ERR_BAD_REQUEST,
          config
        ));
      }
    }

    const contentLength = utils.toFiniteNumber(headers.getContentLength());

    if (utils.isArray(maxRate)) {
      maxUploadRate = maxRate[0];
      maxDownloadRate = maxRate[1];
    } else {
      maxUploadRate = maxDownloadRate = maxRate;
    }

    if (data && (onUploadProgress || maxUploadRate)) {
      if (!utils.isStream(data)) {
        data = stream.Readable.from(data, {objectMode: false});
      }

      data = stream.pipeline([data, new AxiosTransformStream({
        length: contentLength,
        maxRate: utils.toFiniteNumber(maxUploadRate)
      })], utils.noop);

      onUploadProgress && data.on('progress', progress => {
        onUploadProgress(Object.assign(progress, {
          upload: true
        }));
      });
    }

    // HTTP basic authentication
    let auth = undefined;
    if (config.auth) {
      const username = config.auth.username || '';
      const password = config.auth.password || '';
      auth = username + ':' + password;
    }

    if (!auth && parsed.username) {
      const urlUsername = parsed.username;
      const urlPassword = parsed.password;
      auth = urlUsername + ':' + urlPassword;
    }

    auth && headers.delete('authorization');

    let path;

    try {
      path = buildURL(
        parsed.pathname + parsed.search,
        config.params,
        config.paramsSerializer
      ).replace(/^\?/, '');
    } catch (err) {
      const customErr = new Error(err.message);
      customErr.config = config;
      customErr.url = config.url;
      customErr.exists = true;
      return reject(customErr);
    }

    headers.set(
      'Accept-Encoding',
      'gzip, compress, deflate' + (isBrotliSupported ? ', br' : ''), false
      );

    const options = {
      path,
      method: method,
      headers: headers.toJSON(),
      agents: { http: config.httpAgent, https: config.httpsAgent },
      auth,
      protocol,
      beforeRedirect: dispatchBeforeRedirect,
      beforeRedirects: {}
    };

    if (config.socketPath) {
      options.socketPath = config.socketPath;
    } else {
      options.hostname = parsed.hostname;
      options.port = parsed.port;
      setProxy(options, config.proxy, protocol + '//' + parsed.hostname + (parsed.port ? ':' + parsed.port : '') + options.path);
    }

    let transport;
    const isHttpsRequest = isHttps.test(options.protocol);
    options.agent = isHttpsRequest ? config.httpsAgent : config.httpAgent;
    if (config.transport) {
      transport = config.transport;
    } else if (config.maxRedirects === 0) {
      transport = isHttpsRequest ? https : http;
    } else {
      if (config.maxRedirects) {
        options.maxRedirects = config.maxRedirects;
      }
      if (config.beforeRedirect) {
        options.beforeRedirects.config = config.beforeRedirect;
      }
      transport = isHttpsRequest ? httpsFollow : httpFollow;
    }

    if (config.maxBodyLength > -1) {
      options.maxBodyLength = config.maxBodyLength;
    } else {
      // follow-redirects does not skip comparison, so it should always succeed for axios -1 unlimited
      options.maxBodyLength = Infinity;
    }

    if (config.insecureHTTPParser) {
      options.insecureHTTPParser = config.insecureHTTPParser;
    }

    // Create the request
    req = transport.request(options, function handleResponse(res) {
      if (req.destroyed) return;

      const streams = [res];

      const responseLength = +res.headers['content-length'];

      if (onDownloadProgress) {
        const transformStream = new AxiosTransformStream({
          length: utils.toFiniteNumber(responseLength),
          maxRate: utils.toFiniteNumber(maxDownloadRate)
        });

        onDownloadProgress && transformStream.on('progress', progress => {
          onDownloadProgress(Object.assign(progress, {
            download: true
          }));
        });

        streams.push(transformStream);
      }

      // decompress the response body transparently if required
      let responseStream = res;

      // return the last request in case of redirects
      const lastRequest = res.req || req;

      // if decompress disabled we should not decompress
      if (config.decompress !== false && res.headers['content-encoding']) {
        // if no content, but headers still say that it is encoded,
        // remove the header not confuse downstream operations
        if (method === 'HEAD' || res.statusCode === 204) {
          delete res.headers['content-encoding'];
        }

        switch (res.headers['content-encoding']) {
        /*eslint default-case:0*/
        case 'gzip':
        case 'x-gzip':
        case 'compress':
        case 'x-compress':
        case 'deflate':
          // add the unzipper to the body stream processing pipeline
          streams.push(zlib.createUnzip(zlibOptions));

          // remove the content-encoding in order to not confuse downstream operations
          delete res.headers['content-encoding'];
          break;
        case 'br':
          if (isBrotliSupported) {
            streams.push(zlib.createBrotliDecompress(brotliOptions));
            delete res.headers['content-encoding'];
          }
        }
      }

      responseStream = streams.length > 1 ? stream.pipeline(streams, utils.noop) : streams[0];

      const offListeners = stream.finished(responseStream, () => {
        offListeners();
        onFinished();
      });

      const response = {
        status: res.statusCode,
        statusText: res.statusMessage,
        headers: new AxiosHeaders(res.headers),
        config,
        request: lastRequest
      };

      if (responseType === 'stream') {
        response.data = responseStream;
        settle(resolve, reject, response);
      } else {
        const responseBuffer = [];
        let totalResponseBytes = 0;

        responseStream.on('data', function handleStreamData(chunk) {
          responseBuffer.push(chunk);
          totalResponseBytes += chunk.length;

          // make sure the content length is not over the maxContentLength if specified
          if (config.maxContentLength > -1 && totalResponseBytes > config.maxContentLength) {
            // stream.destroy() emit aborted event before calling reject() on Node.js v16
            rejected = true;
            responseStream.destroy();
            reject(new AxiosError('maxContentLength size of ' + config.maxContentLength + ' exceeded',
              AxiosError.ERR_BAD_RESPONSE, config, lastRequest));
          }
        });

        responseStream.on('aborted', function handlerStreamAborted() {
          if (rejected) {
            return;
          }

          const err = new AxiosError(
            'maxContentLength size of ' + config.maxContentLength + ' exceeded',
            AxiosError.ERR_BAD_RESPONSE,
            config,
            lastRequest
          );
          responseStream.destroy(err);
          reject(err);
        });

        responseStream.on('error', function handleStreamError(err) {
          if (req.destroyed) return;
          reject(AxiosError.from(err, null, config, lastRequest));
        });

        responseStream.on('end', function handleStreamEnd() {
          try {
            let responseData = responseBuffer.length === 1 ? responseBuffer[0] : Buffer.concat(responseBuffer);
            if (responseType !== 'arraybuffer') {
              responseData = responseData.toString(responseEncoding);
              if (!responseEncoding || responseEncoding === 'utf8') {
                responseData = utils.stripBOM(responseData);
              }
            }
            response.data = responseData;
          } catch (err) {
            reject(AxiosError.from(err, null, config, response.request, response));
          }
          settle(resolve, reject, response);
        });
      }

      emitter.once('abort', err => {
        if (!responseStream.destroyed) {
          responseStream.emit('error', err);
          responseStream.destroy();
        }
      });
    });

    emitter.once('abort', err => {
      reject(err);
      req.destroy(err);
    });

    // Handle errors
    req.on('error', function handleRequestError(err) {
      // @todo remove
      // if (req.aborted && err.code !== AxiosError.ERR_FR_TOO_MANY_REDIRECTS) return;
      reject(AxiosError.from(err, null, config, req));
    });

    // set tcp keep alive to prevent drop connection by peer
    req.on('socket', function handleRequestSocket(socket) {
      // default interval of sending ack packet is 1 minute
      socket.setKeepAlive(true, 1000 * 60);
    });

    // Handle request timeout
    if (config.timeout) {
      // This is forcing a int timeout to avoid problems if the `req` interface doesn't handle other types.
      const timeout = parseInt(config.timeout, 10);

      if (isNaN(timeout)) {
        reject(new AxiosError(
          'error trying to parse `config.timeout` to int',
          AxiosError.ERR_BAD_OPTION_VALUE,
          config,
          req
        ));

        return;
      }

      // Sometime, the response will be very slow, and does not respond, the connect event will be block by event loop system.
      // And timer callback will be fired, and abort() will be invoked before connection, then get "socket hang up" and code ECONNRESET.
      // At this time, if we have a large number of request, nodejs will hang up some socket on background. and the number will up and up.
      // And then these socket which be hang up will devouring CPU little by little.
      // ClientRequest.setTimeout will be fired on the specify milliseconds, and can make sure that abort() will be fired after connect.
      req.setTimeout(timeout, function handleRequestTimeout() {
        if (isDone) return;
        let timeoutErrorMessage = config.timeout ? 'timeout of ' + config.timeout + 'ms exceeded' : 'timeout exceeded';
        const transitional = config.transitional || transitionalDefaults;
        if (config.timeoutErrorMessage) {
          timeoutErrorMessage = config.timeoutErrorMessage;
        }
        reject(new AxiosError(
          timeoutErrorMessage,
          transitional.clarifyTimeoutError ? AxiosError.ETIMEDOUT : AxiosError.ECONNABORTED,
          config,
          req
        ));
        abort();
      });
    }


    // Send the request
    if (utils.isStream(data)) {
      let ended = false;
      let errored = false;

      data.on('end', () => {
        ended = true;
      });

      data.once('error', err => {
        errored = true;
        req.destroy(err);
      });

      data.on('close', () => {
        if (!ended && !errored) {
          abort(new CanceledError('Request stream has been aborted', config, req));
        }
      });

      data.pipe(req);
    } else {
      req.end(data);
    }
  });
}

export const __setProxy = setProxy;