/**
 * Copyright (c) Meta Platforms, Inc. and 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 type {IOSDeviceParams} from 'flipper-common';
import path from 'path';
import childProcess from 'child_process';
import {exec} from 'promisify-child-process';
import iosUtil from './iOSContainerUtility';
import IOSDevice from './IOSDevice';
import {
  ERR_NO_IDB_OR_XCODE_AVAILABLE,
  IOSBridge,
  makeIOSBridge,
  SimctlBridge,
} from './IOSBridge';
import {FlipperServerImpl} from '../../FlipperServerImpl';
import {notNull} from '../../utils/typeUtils';
import {getFlipperServerConfig} from '../../FlipperServerConfig';
import {IdbConfig, setIdbConfig} from './idbConfig';
import {assertNotNull} from 'flipper-server-core/src/comms/Utilities';

export class IOSDeviceManager {
  private portForwarders: Array<ChildProcess> = [];
  private idbConfig?: IdbConfig;

  private portforwardingClient = path.join(
    getFlipperServerConfig().paths.staticPath,
    'PortForwardingMacApp.app',
    'Contents',
    'MacOS',
    'PortForwardingMacApp',
  );
  iosBridge: IOSBridge | undefined;
  simctlBridge: SimctlBridge = new SimctlBridge();
  private xcodeVersionMismatchFound = false;
  public xcodeCommandLineToolsDetected = false;

  constructor(private flipperServer: FlipperServerImpl) {}

  private forwardPort(port: number, multiplexChannelPort: number) {
    const child = childProcess.execFile(
      this.portforwardingClient,
      [`-portForward=${port}`, `-multiplexChannelPort=${multiplexChannelPort}`],
      (err, stdout, stderr) => {
        if (err) {
          // This happens on app reloads and doesn't need to be treated as an error.
          console.warn(
            '[conn] Port forwarding app failed to start',
            err,
            stdout,
            stderr,
          );
        }
      },
    );
    console.info(
      `[conn] Port forwarding app started (portForward: ${port}, multiplexChannelPort: ${multiplexChannelPort})`,
    );
    child.addListener('error', (err) =>
      console.warn('[conn] Port forwarding app error', err),
    );
    child.addListener('exit', (code) => {
      if (code != 0) {
        console.warn(`[conn] Port forwarding app exited with code ${code}`);
      } else {
        console.log(`[conn] Port forwarding app exited gracefully`);
      }
    });
    return child;
  }

  private startDevicePortForwarders(): void {
    if (this.portForwarders.length > 0) {
      // Only ever start them once.
      return;
    }
    // start port forwarding server for real device connections
    // TODO: ports should be picked up from flipperServer.config?
    this.portForwarders = [
      this.forwardPort(8089, 8079),
      this.forwardPort(8088, 8078),
    ];
  }

  getAllPromisesForQueryingDevices(
    isXcodeDetected: boolean,
    isIdbAvailable: boolean,
  ): Array<Promise<any>> {
    assertNotNull(this.idbConfig);
    return [
      isIdbAvailable
        ? getActiveDevices(
            this.idbConfig.idbPath,
            this.idbConfig.enablePhysicalIOS,
          ).then((devices: IOSDeviceParams[]) => {
            this.processDevices(devices);
          })
        : null,
      !isIdbAvailable && isXcodeDetected
        ? this.getSimulators(true).then((devices) =>
            this.processDevices(devices),
          )
        : null,
      isXcodeDetected ? this.checkXcodeVersionMismatch() : null,
    ].filter(notNull);
  }

  private async queryDevices(): Promise<any> {
    assertNotNull(this.idbConfig);
    const isXcodeInstalled = await iosUtil.isXcodeDetected();
    const isIdbAvailable = await iosUtil.isAvailable(this.idbConfig.idbPath);
    console.debug(
      `[conn] queryDevices. isXcodeInstalled ${isXcodeInstalled}, isIdbAvailable ${isIdbAvailable}`,
    );
    return Promise.all(
      this.getAllPromisesForQueryingDevices(isXcodeInstalled, isIdbAvailable),
    );
  }

  private processDevices(activeDevices: IOSDeviceParams[]) {
    console.debug('[conn] processDevices', activeDevices);
    if (!this.iosBridge) {
      throw new Error('iOS bridge not yet initialized');
    }
    const currentDeviceIDs = new Set(
      this.flipperServer
        .getDevices()
        .filter((device) => device.info.os === 'iOS')
        .map((device) => device.serial),
    );
    console.debug(
      '[conn] processDevices -> currentDeviceIDs',
      currentDeviceIDs,
    );

    for (const activeDevice of activeDevices) {
      const {udid, type, name} = activeDevice;
      if (currentDeviceIDs.has(udid)) {
        currentDeviceIDs.delete(udid);
      } else {
        console.info(`[conn] detected new iOS device ${udid}`, activeDevice);
        const iOSDevice = new IOSDevice(
          this.flipperServer,
          this.iosBridge,
          udid,
          type,
          name,
        );
        this.flipperServer.registerDevice(iOSDevice);
      }
    }

    currentDeviceIDs.forEach((id) => {
      console.info(`[conn] Could no longer find ${id}, removing...`);
      this.flipperServer.unregisterDevice(id);
    });
  }

  public async watchIOSDevices() {
    const settings = getFlipperServerConfig().settings;
    this.idbConfig = setIdbConfig(settings);
    try {
      const isDetected = await iosUtil.isXcodeDetected();
      this.xcodeCommandLineToolsDetected = isDetected;
      if (settings.enablePhysicalIOS) {
        this.startDevicePortForwarders();
      }
      try {
        // Awaiting the promise here to trigger immediate error handling.
        this.iosBridge = await makeIOSBridge(settings.idbPath, isDetected);
        this.queryDevicesForever();
      } catch (err) {
        // This case is expected if both Xcode and idb are missing.
        if (err.message === ERR_NO_IDB_OR_XCODE_AVAILABLE) {
          console.warn(
            'Failed to init iOS device. You may want to disable iOS support in the settings.',
            err,
          );
        } else {
          console.error('Failed to initialize iOS dispatcher:', err);
        }
      }
    } catch (err) {
      console.error('Error while querying iOS devices:', err);
    }
  }

  getSimulators(bootedOnly: boolean): Promise<Array<IOSDeviceParams>> {
    return this.simctlBridge.getActiveDevices(bootedOnly).catch((e: Error) => {
      console.warn('Failed to query simulators:', e);
      if (e.message.includes('Xcode license agreements')) {
        this.flipperServer.emit('notification', {
          type: 'error',
          title: 'Xcode license requires approval',
          description:
            'The Xcode license agreement has changed. You need to either open Xcode and agree to the terms or run `sudo xcodebuild -license` in a Terminal to allow simulators to work with Flipper.',
        });
      }
      return Promise.resolve([]);
    });
  }

  private queryDevicesForever() {
    return this.queryDevices()
      .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(() => this.queryDevicesForever(), 3000);
      })
      .catch((err) => {
        console.warn('Failed to continuously query devices:', err);
      });
  }

  async checkXcodeVersionMismatch() {
    if (this.xcodeVersionMismatchFound) {
      return;
    }
    try {
      let {stdout: xcodeCLIVersion} = await exec('xcode-select -p');
      xcodeCLIVersion = xcodeCLIVersion!.toString().trim();
      const {stdout} = await exec('ps aux | grep CoreSimulator');
      for (const line of stdout!.toString().split('\n')) {
        const match = parseXcodeFromCoreSimPath(line);
        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. For example: "sudo xcode-select -s /Applications/Xcode.app/Contents/Developer"`;
          this.flipperServer.emit('notification', {
            type: 'error',
            title: 'Xcode version mismatch',
            description: '' + errorMessage,
          });
          this.xcodeVersionMismatchFound = true;
          break;
        }
      }
    } catch (e) {
      console.error('Failed to determine Xcode version:', e);
    }
  }
}

function getActiveDevices(
  idbPath: string,
  isPhysicalDeviceEnabled: boolean,
): Promise<Array<IOSDeviceParams>> {
  return iosUtil.targets(idbPath, isPhysicalDeviceEnabled).catch((e) => {
    console.error('Failed to get active iOS devices:', e.message);
    return [];
  });
}

export function parseXcodeFromCoreSimPath(
  line: string,
): RegExpMatchArray | null {
  return line.match(/\/[\/\w@)(\-\+]*\/Xcode[^/]*\.app\/Contents\/Developer/);
}