import _ from 'lodash';
import {waitForCondition} from 'asyncbox';
import {util, fs, tempDir} from 'appium/support';
import {SubProcess} from 'teen_process';
import B from 'bluebird';
import {uploadRecordedMedia} from './helpers';
import type {Mac2Driver} from '../driver';
import type {AppiumLogger, StringRecord} from '@appium/types';

const RETRY_PAUSE = 300;
const RETRY_TIMEOUT = 5000;
const DEFAULT_TIME_LIMIT = 60 * 10; // 10 minutes
const PROCESS_SHUTDOWN_TIMEOUT = 10 * 1000;
const DEFAULT_EXT = 'mp4';
const FFMPEG_BINARY = 'ffmpeg';
const DEFAULT_FPS = 15;
const DEFAULT_PRESET = 'veryfast';

type Preset =
  | 'ultrafast'
  | 'superfast'
  | 'veryfast'
  | 'faster'
  | 'fast'
  | 'medium'
  | 'slow'
  | 'slower'
  | 'veryslow';

interface ScreenRecorderOptions {
  fps?: number;
  deviceId: string | number;
  preset?: Preset;
  captureCursor?: boolean;
  captureClicks?: boolean;
  videoFilter?: string;
  timeLimit?: number;
}

/**
 * @param log - Logger instance
 */
async function requireFfmpegPath(log: AppiumLogger): Promise<string> {
  try {
    return await fs.which(FFMPEG_BINARY);
  } catch {
    throw log.errorWithException(
      `${FFMPEG_BINARY} has not been found in PATH. ` + `Please make sure it is installed`,
    );
  }
}

export class ScreenRecorder {
  private readonly _log: AppiumLogger;
  private readonly _videoPath: string;
  private _process: SubProcess | null;
  private readonly _fps: number;
  private readonly _deviceId: string | number;
  private readonly _captureCursor?: boolean;
  private readonly _captureClicks?: boolean;
  private readonly _preset: Preset;
  private readonly _videoFilter?: string;
  private readonly _timeLimit: number;

  /**
   *
   * @param videoPath - Path to the video file
   * @param log - Logger instance
   * @param opts - Screen recorder options
   */
  constructor(videoPath: string, log: AppiumLogger, opts: ScreenRecorderOptions) {
    this._log = log;
    this._videoPath = videoPath;
    this._process = null;
    this._fps = opts.fps && opts.fps > 0 ? opts.fps : DEFAULT_FPS;
    this._deviceId = opts.deviceId;
    this._captureCursor = opts.captureCursor;
    this._captureClicks = opts.captureClicks;
    this._preset = opts.preset || DEFAULT_PRESET;
    this._videoFilter = opts.videoFilter;
    this._timeLimit = opts.timeLimit && opts.timeLimit > 0 ? opts.timeLimit : DEFAULT_TIME_LIMIT;
  }

  async getVideoPath(): Promise<string> {
    return (await fs.exists(this._videoPath)) ? this._videoPath : '';
  }

  isRunning(): boolean {
    return !!this._process?.isRunning;
  }

  async start(): Promise<void> {
    const ffmpeg = await requireFfmpegPath(this._log);

    const args: string[] = [
      '-loglevel',
      'error',
      '-t',
      `${this._timeLimit}`,
      '-f',
      'avfoundation',
      ...(this._captureCursor ? ['-capture_cursor', '1'] : []),
      ...(this._captureClicks ? ['-capture_mouse_clicks', '1'] : []),
      '-framerate',
      `${this._fps}`,
      '-i',
      `${this._deviceId}`,
      '-vcodec',
      'libx264',
      '-preset',
      this._preset,
      '-tune',
      'zerolatency',
      '-pix_fmt',
      'yuv420p',
      '-movflags',
      '+faststart',
      '-fflags',
      'nobuffer',
      '-f',
      DEFAULT_EXT,
      '-r',
      `${this._fps}`,
      ...(this._videoFilter ? ['-filter:v', this._videoFilter] : []),
    ];

    const fullCmd: string[] = [ffmpeg, ...args, this._videoPath];
    this._process = new SubProcess(fullCmd[0], fullCmd.slice(1));
    this._log.debug(`Starting ${FFMPEG_BINARY}: ${util.quote(fullCmd)}`);
    this._process.on('output', (stdout, stderr) => {
      if (_.trim(stdout || stderr)) {
        this._log.debug(`[${FFMPEG_BINARY}] ${stdout || stderr}`);
      }
    });
    this._process.once('exit', async (code, signal) => {
      this._process = null;
      if (code === 0) {
        this._log.debug('Screen recording exited without errors');
      } else {
        await this._enforceTermination();
        this._log.warn(`Screen recording exited with error code ${code}, signal ${signal}`);
      }
    });
    await this._process.start(0);
    try {
      await waitForCondition(
        async () => {
          if (await this.getVideoPath()) {
            return true;
          }
          if (!this._process) {
            throw new Error(`${FFMPEG_BINARY} process died unexpectedly`);
          }
          return false;
        },
        {
          waitMs: RETRY_TIMEOUT,
          intervalMs: RETRY_PAUSE,
        },
      );
    } catch {
      await this._enforceTermination();
      throw this._log.errorWithException(
        `The expected screen record file '${this._videoPath}' does not exist. ` +
          `Check the server log for more details`,
      );
    }
    this._log.info(
      `The video recording has started. Will timeout in ${util.pluralize('second', this._timeLimit, true)}`,
    );
  }

  async stop(force: boolean = false): Promise<string> {
    if (force) {
      return await this._enforceTermination();
    }

    if (!this.isRunning()) {
      this._log.debug('Screen recording is not running. Returning the recent result');
      return await this.getVideoPath();
    }

    return new B((resolve, reject) => {
      const timer = setTimeout(async () => {
        await this._enforceTermination();
        reject(
          new Error(`Screen recording has failed to exit after ${PROCESS_SHUTDOWN_TIMEOUT}ms`),
        );
      }, PROCESS_SHUTDOWN_TIMEOUT);

      this._process?.once('exit', async (code, signal) => {
        clearTimeout(timer);
        if (code === 0) {
          resolve(await this.getVideoPath());
        } else {
          reject(new Error(`Screen recording exited with error code ${code}, signal ${signal}`));
        }
      });

      this._process?.proc?.stdin?.write('q');
      this._process?.proc?.stdin?.end();
    });
  }

  private async _enforceTermination(): Promise<string> {
    if (this._process && this.isRunning()) {
      this._log.debug('Force-stopping the currently running video recording');
      try {
        await this._process.stop('SIGKILL');
      } catch {
        // Ignore errors during force stop
      }
    }
    this._process = null;
    const videoPath = await this.getVideoPath();
    if (videoPath) {
      await fs.rimraf(videoPath);
    }
    return '';
  }
}

/**
 * Record the display in background while the automated test is running.
 * This method requires FFMPEG (https://www.ffmpeg.org/download.html) to be installed
 * and present in PATH. Also, the Appium process must be allowed to access screen recording
 * in System Preferences->Security & Privacy->Screen Recording.
 * The resulting video uses H264 codec and is ready to be played by media players built-in into web browsers.
 *
 * @param deviceId - Screen device index to use for the recording.
 *                        The list of available devices could be retrieved using
 *                       `ffmpeg -f avfoundation -list_devices true -i` command.
 * @param timeLimit - The maximum recording time, in seconds. The default
 *                        value is 600 seconds (10 minutes).
 * @param videoFilter - The video filter spec to apply for ffmpeg.
 *                 See https://trac.ffmpeg.org/wiki/FilteringGuide for more details on the possible values.
 *                 Example: Set it to `scale=ifnot(gte(iw\,1024)\,iw\,1024):-2` in order to limit the video width
 *                 to 1024px. The height will be adjusted automatically to match the actual ratio.
 * @param fps - The count of frames per second in the resulting video.
 *                        The greater fps it has the bigger file size is. 15 by default.
 * @param preset - One of the supported encoding presets. A preset is a collection of options that will provide a
 *         certain encoding speed to compression ratio.
 *         A slower preset will provide better compression (compression is quality per filesize).
 *         This means that, for example, if you target a certain file size or constant bit rate, you will
 *         achieve better quality with a slower preset. Read https://trac.ffmpeg.org/wiki/Encode/H.264 for more details.
 *         `veryfast` by default
 * @param captureCursor - Whether to capture the mouse cursor while recording the screen.
 *                  False by default
 * @param captureClicks - Whether to capture mouse clicks while recording the screen.
 *                  False by default.
 * @param forceRestart - Whether to ignore the call if a screen recording is currently running
 *                (`false`) or to start a new recording immediately and terminate the existing one
 *                if running (`true`). The default value is `true`.
 * @throws {Error} If screen recording has failed to start or is not supported on the device under test.
 */
export async function startRecordingScreen(
  this: Mac2Driver,
  deviceId: string | number,
  timeLimit?: string | number,
  videoFilter?: string,
  fps?: string | number,
  preset?: Preset,
  captureCursor?: boolean,
  captureClicks?: boolean,
  forceRestart: boolean = true,
): Promise<void> {
  if (_.isNil(deviceId)) {
    throw new Error(
      `'deviceId' option must be provided. Run 'ffmpeg -f avfoundation -list_devices true -i' ` +
        'to fetch the list of available device ids',
    );
  }

  if (this._screenRecorder?.isRunning?.()) {
    this.log.debug('The screen recording is already running');
    if (!forceRestart) {
      this.log.debug('Doing nothing');
      return;
    }
    this.log.debug('Forcing the active screen recording to stop');
    await this._screenRecorder.stop(true);
  }
  this._screenRecorder = null;

  const videoPath = await tempDir.path({
    prefix: util.uuidV4().substring(0, 8),
    suffix: `.${DEFAULT_EXT}`,
  });
  this._screenRecorder = new ScreenRecorder(videoPath, this.log, {
    fps: parseInt(`${fps}`, 10),
    timeLimit: parseInt(`${timeLimit}`, 10),
    preset,
    captureCursor,
    captureClicks,
    videoFilter,
    deviceId,
  });
  try {
    await this._screenRecorder.start();
  } catch (e) {
    this._screenRecorder = null;
    throw e;
  }
}

/**
 * Stop recording the screen.
 * If no screen recording has been started before then the method returns an empty string.
 *
 * @param remotePath - The path to the remote location, where the resulting video should be uploaded.
 *                              The following protocols are supported: http/https, ftp.
 *                              Null or empty string value (the default setting) means the content of resulting
 *                              file should be encoded as Base64 and passed as the endpoint response value.
 *                              An exception will be thrown if the generated media file is too big to
 *                              fit into the available process memory.
 * @param user - The name of the user for the remote authentication.
 * @param pass - The password for the remote authentication.
 * @param method - The http multipart upload method name. The 'PUT' one is used by default.
 * @param headers - Additional headers mapping for multipart http(s) uploads
 * @param fileFieldName - The name of the form field, where the file content BLOB should
 *                                 be stored for http(s) uploads
 * @param formFields - Additional form fields for multipart http(s) uploads
 * @returns Base64-encoded content of the recorded media file if 'remotePath'
 * parameter is falsy or an empty string.
 * @throws {Error} If there was an error while getting the name of a media file
 * or the file content cannot be uploaded to the remote location
 * or screen recording is not supported on the device under test.
 */
export async function stopRecordingScreen(
  this: Mac2Driver,
  remotePath?: string | null,
  user?: string,
  pass?: string,
  method?: string,
  headers?: StringRecord | [string, any][],
  fileFieldName?: string,
  formFields?: StringRecord | [string, string][],
): Promise<string> {
  if (!this._screenRecorder) {
    this.log.debug('No screen recording has been started. Doing nothing');
    return '';
  }

  this.log.debug('Retrieving the resulting video data');
  const videoPath = await this._screenRecorder.stop();
  if (!videoPath) {
    this.log.debug('No video data is found. Returning an empty string');
    return '';
  }
  const options: StringRecord = {
    user,
    pass,
    method,
    headers,
    fileFieldName,
    formFields,
  };
  return await uploadRecordedMedia.bind(this)(videoPath, remotePath, options);
}