/**
 * Copyright (c) Facebook, Inc. and its affiliates.
 *
 * This source code is licensed under the MIT license found in the
 * LICENSE file in the root directory of this source tree.
 *
 * @format
 */

import {ChildProcess} from 'child_process';
import {Store} from '../reducers/index';
import {setXcodeDetected} from '../reducers/application';
import {Logger} from '../fb-interfaces/Logger';
import type {DeviceType} from 'flipper-plugin';
import {promisify} from 'util';
import path from 'path';
import child_process from 'child_process';
const execFile = child_process.execFile;
import iosUtil from '../utils/iOSContainerUtility';
import IOSDevice from '../devices/IOSDevice';
import isProduction from '../utils/isProduction';
import {registerDeviceCallbackOnPlugins} from '../utils/onRegisterDevice';

type iOSSimulatorDevice = {
  state: 'Booted' | 'Shutdown' | 'Shutting Down';
  availability?: string;
  isAvailable?: 'YES' | 'NO' | true | false;
  name: string;
  udid: string;
};

type IOSDeviceParams = {udid: string; type: DeviceType; name: string};

const exec = promisify(child_process.exec);

let portForwarders: Array<ChildProcess> = [];

function isAvailable(simulator: iOSSimulatorDevice): boolean {
  // For some users "availability" is set, for others it's "isAvailable"
  // It's not clear which key is set, so we are checking both.
  // We've also seen isAvailable return "YES" and true, depending on version.
  return (
    simulator.availability === '(available)' ||
    simulator.isAvailable === 'YES' ||
    simulator.isAvailable === true
  );
}

const portforwardingClient = isProduction()
  ? path.resolve(
      __dirname,
      'PortForwardingMacApp.app/Contents/MacOS/PortForwardingMacApp',
    )
  : 'PortForwardingMacApp.app/Contents/MacOS/PortForwardingMacApp';

function forwardPort(port: number, multiplexChannelPort: number) {
  return execFile(portforwardingClient, [
    `-portForward=${port}`,
    `-multiplexChannelPort=${multiplexChannelPort}`,
  ]);
}

function startDevicePortForwarders(): void {
  if (portForwarders.length > 0) {
    // Only ever start them once.
    return;
  }
  // start port forwarding server for real device connections
  portForwarders = [forwardPort(8089, 8079), forwardPort(8088, 8078)];
}

if (typeof window !== 'undefined') {
  window.addEventListener('beforeunload', () => {
    portForwarders.forEach((process) => process.kill());
  });
}

async function queryDevices(store: Store, logger: Logger): Promise<any> {
  return Promise.all([
    checkXcodeVersionMismatch(store),
    getActiveSimulators().then((devices) => {
      processDevices(store, logger, devices, 'emulator');
    }),
    getActiveDevices().then((devices) => {
      processDevices(store, logger, devices, 'physical');
    }),
  ]);
}

function processDevices(
  store: Store,
  logger: Logger,
  activeDevices: IOSDeviceParams[],
  type: 'physical' | 'emulator',
) {
  const {connections} = store.getState();
  const currentDeviceIDs: Set<string> = new Set(
    connections.devices
      .filter(
        (device) =>
          device instanceof IOSDevice &&
          device.deviceType === type &&
          !device.isArchived,
      )
      .map((device) => device.serial),
  );

  for (const {udid, type, name} of activeDevices) {
    if (currentDeviceIDs.has(udid)) {
      currentDeviceIDs.delete(udid);
    } else {
      logger.track('usage', 'register-device', {
        os: 'iOS',
        type: type,
        name: name,
        serial: udid,
      });
      const iOSDevice = new IOSDevice(udid, type, name);
      iOSDevice.loadDevicePlugins(store.getState().plugins.devicePlugins);
      store.dispatch({
        type: 'REGISTER_DEVICE',
        payload: iOSDevice,
      });
      registerDeviceCallbackOnPlugins(
        store,
        store.getState().plugins.devicePlugins,
        store.getState().plugins.clientPlugins,
        iOSDevice,
      );
    }
  }

  if (currentDeviceIDs.size > 0) {
    currentDeviceIDs.forEach((id) =>
      logger.track('usage', 'unregister-device', {os: 'iOS', serial: id}),
    );
    store.dispatch({
      type: 'UNREGISTER_DEVICES',
      payload: currentDeviceIDs,
    });
  }
}

function getActiveSimulators(): Promise<Array<IOSDeviceParams>> {
  const deviceSetPath = process.env.DEVICE_SET_PATH
    ? ['--set', process.env.DEVICE_SET_PATH]
    : [];
  return promisify(execFile)(
    'xcrun',
    ['simctl', ...deviceSetPath, 'list', 'devices', '--json'],
    {
      encoding: 'utf8',
    },
  )
    .then(({stdout}) => JSON.parse(stdout).devices)
    .then((simulatorDevices: Array<iOSSimulatorDevice>) => {
      const simulators: Array<iOSSimulatorDevice> = Object.values(
        simulatorDevices,
      ).reduce((acc: Array<iOSSimulatorDevice>, cv) => acc.concat(cv), []);

      return simulators
        .filter(
          (simulator) => simulator.state === 'Booted' && isAvailable(simulator),
        )
        .map((simulator) => {
          return {
            udid: simulator.udid,
            type: 'emulator',
            name: simulator.name,
          } as IOSDeviceParams;
        });
    })
    .catch((_) => []);
}

function getActiveDevices(): Promise<Array<IOSDeviceParams>> {
  return iosUtil.targets().catch((e) => {
    console.error(e.message);
    return [];
  });
}

function queryDevicesForever(store: Store, logger: Logger) {
  return queryDevices(store, logger)
    .then(() => {
      // It's important to schedule the next check AFTER the current one has completed
      // to avoid simultaneous queries which can cause multiple user input prompts.
      setTimeout(() => queryDevicesForever(store, logger), 3000);
    })
    .catch((err) => {
      console.error(err);
    });
}

let xcodeVersionMismatchFound = false;
async function checkXcodeVersionMismatch(store: Store) {
  if (xcodeVersionMismatchFound) {
    return;
  }
  try {
    let {stdout: xcodeCLIVersion} = await exec('xcode-select -p');
    xcodeCLIVersion = xcodeCLIVersion.trim();
    const {stdout} = await exec('ps aux | grep CoreSimulator');
    for (const line of stdout.split('\n')) {
      const match = line.match(
        /\/Applications\/Xcode[^/]*\.app\/Contents\/Developer/,
      );
      const runningVersion = match && match.length > 0 ? match[0].trim() : null;
      if (runningVersion && runningVersion !== xcodeCLIVersion) {
        const errorMessage = `Xcode version mismatch: Simulator is running from "${runningVersion}" while Xcode CLI is "${xcodeCLIVersion}". Running "xcode-select --switch ${runningVersion}" can fix this.`;
        store.dispatch({
          type: 'SERVER_ERROR',
          payload: {
            message: errorMessage,
            details:
              "You might want to run 'sudo xcode-select -s /Applications/Xcode.app/Contents/Developer'",
            urgent: true,
          },
        });
        // Fire a console.error as well, so that it gets reported to the backend.
        console.error(errorMessage);
        xcodeVersionMismatchFound = true;
        break;
      }
    }
  } catch (e) {
    console.error(e);
  }
}
async function isXcodeDetected(): Promise<boolean> {
  return exec('xcode-select -p')
    .then((_) => true)
    .catch((_) => false);
}

export async function getActiveDevicesAndSimulators(): Promise<
  Array<IOSDevice>
> {
  const activeDevices: Array<Array<IOSDeviceParams>> = await Promise.all([
    getActiveSimulators(),
    getActiveDevices(),
  ]);
  const allDevices = activeDevices[0].concat(activeDevices[1]);
  return allDevices.map((device) => {
    const {udid, type, name} = device;
    return new IOSDevice(udid, type, name);
  });
}

export default (store: Store, logger: Logger) => {
  // monitoring iOS devices only available on MacOS.
  if (process.platform !== 'darwin') {
    return;
  }
  if (!store.getState().settingsState.enableIOS) {
    return;
  }
  isXcodeDetected().then((isDetected) => {
    store.dispatch(setXcodeDetected(isDetected));
    if (isDetected) {
      if (store.getState().settingsState.enablePhysicalIOS) {
        startDevicePortForwarders();
      }
      return queryDevicesForever(store, logger);
    }
  });
};