import {
  API,
  APIEvent,
  Characteristic,
  DynamicPlatformPlugin,
  Logger,
  PlatformAccessory,
  PlatformConfig,
  Service,
} from 'homebridge';
import * as cheerio from 'cheerio';
import ComfortCloudApi from './comfort-cloud';
import IndoorUnitAccessory from './indoor-unit';
import PanasonicPlatformLogger from './logger';
import { PanasonicAccessoryContext, PanasonicPlatformConfig } from './types';
import {
  PLATFORM_NAME,
  PLUGIN_NAME,
  APP_VERSION,
} from './settings';


/**
 * Panasonic AC Platform Plugin for Homebridge
 * Based on https://github.com/homebridge/homebridge-plugin-template
 */
export default class PanasonicPlatform implements DynamicPlatformPlugin {
  public readonly Service: typeof Service = this.api.hap.Service;
  public readonly Characteristic: typeof Characteristic = this.api.hap.Characteristic;

  // Used to track restored cached accessories
  private readonly accessories: PlatformAccessory<PanasonicAccessoryContext>[] = [];

  private _loginRetryTimeout;
  private noOfFailedLoginAttempts = 0;

  public readonly comfortCloud: ComfortCloudApi;
  public readonly log: PanasonicPlatformLogger;

  public platformConfig: PanasonicPlatformConfig;

  /**
   * This constructor is where you should parse the user config
   * and discover/register accessories with Homebridge.
   *
   * @param logger Homebridge logger
   * @param config Homebridge platform config
   * @param api Homebridge API
   */
  constructor(
    homebridgeLogger: Logger,
    config: PlatformConfig,
    private readonly api: API,
  ) {
    this.platformConfig = config as PanasonicPlatformConfig;

    // Initialise logging utility
    this.log = new PanasonicPlatformLogger(homebridgeLogger, this.platformConfig.logsLevel);

    // Create Comfort Cloud communication module
    this.comfortCloud = new ComfortCloudApi(
      this.platformConfig,
      this.log,
    );

    /**
     * When this event is fired it means Homebridge has restored all cached accessories from disk.
     * Dynamic Platform plugins should only register new accessories after this event was fired,
     * in order to ensure they weren't added to homebridge already. This event can also be used
     * to start discovery of new accessories.
     */
    this.api.on(APIEvent.DID_FINISH_LAUNCHING, () => {
      this.log.debug('Finished launching and restored cached accessories.');
      this.configurePlugin();
    });
  }

  async configurePlugin() {
    this.log.info(`Plugin app version: ${APP_VERSION}.`);
    if (this.platformConfig.overwriteVersion) {
      this.log.info(`Overwrite Version: ${this.platformConfig.overwriteVersion}.`);
    }
    await this.getAppStoreVersion();
    await this.loginAndDiscoverDevices();
  }

  async getAppStoreVersion() {
    this.log.debug('Attempting to fetch latest Comfort Cloud version from the App Store.');
    const $ = await cheerio.fromURL('https://apps.apple.com/app/panasonic-comfort-cloud/id1348640525');
    const matches = $('p.whats-new__latest__version').first().text().match(/\d+(.)\d+(.)\d+/);
    if (Array.isArray(matches)) {
      this.log.info(`App Store app version: ${matches[0]}.`);
    } else {
      this.log.error('Could not find App Store app version.');
      await this.getPlayStoreVersion();
    }
  }

  async getPlayStoreVersion() {
    // Version data is not displayed in clear text on the page, but instead included in some cryptic JS function call.
    // The function call is `AF_initDataCallback()`, but there are many of them.
    // The function call additionally contains (several) references to the app store page for the app in other languages,
    // so it also contains the package name which allows us to further narrow it down.
    // Finally, the version number is of the format major.minor.patch, surrounded by quotation marks.
    this.log.debug('Attempting to fetch latest Comfort Cloud version from the Play Store.');
    const $ = await cheerio.fromURL('https://play.google.com/store/apps/details?id=com.panasonic.ACCsmart');

    $('script').each((idx, script) => {
      const textContent = $(script).text();
      const isCallback = textContent.includes('AF_initDataCallback(') && textContent.includes('com.panasonic.ACCsmart');
      if (isCallback) {
        const matches = textContent.match(/['"](\d+\.\d+\.\d+)['"]/);
        if (Array.isArray(matches) && (1 in matches)) {
          this.log.info(`Play Store app version: ${matches[1]}.`);
        }
      }
    });
  }

  async loginAndDiscoverDevices() {
    if (!this.platformConfig.email) {
      this.log.error('Email is not configured - aborting plugin start. '
        + 'Please set the field `email` in your config and restart Homebridge.');
      return;
    }

    if (!this.platformConfig.password) {
      this.log.error('Password is not configured - aborting plugin start. '
        + 'Please set the field `password` in your config and restart Homebridge.');
      return;
    }

    this.log.debug('Attempting to log into Comfort Cloud.');
    this.comfortCloud.login()
      .then(() => {
        this.log.info('Successfully logged in to Comfort Cloud.');
        this.noOfFailedLoginAttempts = 0;
        this.discoverDevices();
      })
      .catch((error) => {
        this.noOfFailedLoginAttempts++;

        this.log.error(`Error: ${error.message}`);

        if (error.message === 'Request failed with status code 429') {
          this.log.error('Too many incorect login attempts '
            + 'or other suspicious activity on the account.'
            + 'You have to wait until Panasonic will unlock the account '
            + '(it may take up to 24 hours) '
            + 'or change IP of Homebridge (restart router). ');
          this.log.error('Next login attempt in 8 hours.');
          clearTimeout(this._loginRetryTimeout);
          this._loginRetryTimeout = setTimeout(
            this.loginAndDiscoverDevices.bind(this),
            28800 * 1000,
          );
        } else if (error.message === 'Request failed with status code 401') {
          this.log.error('Incorect login / password or incorect app version.'
                         + 'Enter the correct values in the plugin settings and restart.');
          this.log.error('Next login attempt in 8 hours.');
          clearTimeout(this._loginRetryTimeout);
          this._loginRetryTimeout = setTimeout(
            this.loginAndDiscoverDevices.bind(this),
            28800 * 1000,
          );
        } else {
          this.log.error(
            'The Comfort Cloud server might be experiencing issues at the moment. '
            + 'If issue persists check Truobleshooting section in plugin homepage.');

          const delayMap = new Map([
            [1, 300], // 5 min
            [2, 1800], // 30 min
            [3, 3600], // 60 min
          ]);
          const nextRetryDelay = delayMap.get(this.noOfFailedLoginAttempts) || 28800;

          this.log.error(`Next login attempt in ${nextRetryDelay / 60} minutes.`);
          clearTimeout(this._loginRetryTimeout);
          this._loginRetryTimeout = setTimeout(
            this.loginAndDiscoverDevices.bind(this),
            nextRetryDelay * 1000,
          );
        }

      });
  }

  /**
   * This function is invoked when Homebridge restores cached accessories from disk at startup.
   * It should be used to set up event handlers for characteristics and update respective values.
   */
  configureAccessory(accessory: PlatformAccessory<PanasonicAccessoryContext>) {
    this.log.info(`Loading accessory '${accessory.displayName}' from cache.`);

    /**
     * We don't have to set up the handlers here,
     * because our device discovery function takes care of that.
     *
     * But we need to add the restored accessory to the
     * accessories cache so we can access it during that process.
     */
    this.accessories.push(accessory);
  }


  /**
   * Fetches all of the user's devices from Comfort Cloud and sets up handlers.
   *
   * Accessories must only be registered once. Previously created accessories
   * must not be registered again to prevent "duplicate UUID" errors.
   */
  async discoverDevices() {
    this.log.debug('Discovering devices on Comfort Cloud.');

    try {
      // Fetch devices from Comfort Cloud
      let cloudDevices = await this.comfortCloud.getDevices();
      this.log.info(`Comfort Cloud total devices: ${Object.keys(cloudDevices).length}.`);
      this.log.debug(`Comfort Cloud devices: ${JSON.stringify(cloudDevices, null, 2)}`);

      // Get devices from plugin configuration
      const configDevices = (this.platformConfig?.devices || []).filter(device => device.name && device.name !== '');

      // Check if there is at least one device added to plugin config
      if (configDevices.length > 0) {
        this.log.info(`Plugin config total devices: ${configDevices.length}.`);
        this.log.debug(`Plugin config devices: ${JSON.stringify(configDevices, null, 2)}.`);

        // Find devices in config that don't exist in Comfort Cloud
        const missingDevices = configDevices
          .filter(configDevice =>
            cloudDevices.every(cloudDevice =>
              cloudDevice.deviceName !== configDevice.name
              && cloudDevice.deviceGuid !== configDevice.name,
            ),
          )
          .map(device => device.name);

        if (missingDevices.length > 0) {
          this.log.info('Devices added to plugin config but not found '
            + `in Comfort Cloud: ${missingDevices.length}. `
            + `Missing devices: ${missingDevices.join(', ')}.`,
          );
        }

        // Exclude by individual device config
        const devicesToExclude = configDevices
          .filter(device => device.excludeDevice === true)
          .map(device => device.name);

        if (devicesToExclude.length > 0) {
          cloudDevices = cloudDevices.filter(cloudDevice =>
            !devicesToExclude.includes(cloudDevice.deviceGuid)
            && !devicesToExclude.includes(cloudDevice.deviceName),
          );
          this.log.info(`Devices added to plugin config to exclude: ${devicesToExclude.length}. `
            + `Devices to exclude: ${devicesToExclude.join(', ')}.`,
          );
        }
      } else {
        this.log.info('Plugin config total devices: 0.');
      }

      // Loop over the discovered (indoor) devices and register each
      // one if it has not been registered before.
      for (const device of cloudDevices) {

        // Generate a unique id for the accessory.
        // This should be generated from something globally unique,
        // but constant, for example, the device serial number or MAC address
        const uuid = this.api.hap.uuid.generate(device.deviceGuid);

        // Check if an accessory with the same uuid has already been registered and restored from
        // the cached devices we stored in the `configureAccessory` method above.
        const existingAccessory = this.accessories.find(accessory => accessory.UUID === uuid);

        if (existingAccessory !== undefined) {
          // The accessory already exists
          this.log.info(`Restoring device '${existingAccessory.displayName}' `
            + `(${device.deviceGuid})(${uuid}) from cache.`);

          // If you need to update the accessory.context then you should run
          // `api.updatePlatformAccessories`. eg.:
          existingAccessory.context.device = device;
          this.api.updatePlatformAccessories([existingAccessory]);

          // Create the accessory handler for the restored accessory
          new IndoorUnitAccessory(this, existingAccessory);
        } else {
          this.log.info(`Adding device '${device.deviceName}' (${device.deviceGuid})(${uuid}).`);
          // The accessory does not yet exist, so we need to create it
          const accessory = new this.api.platformAccessory<PanasonicAccessoryContext>(
            device.deviceName, uuid);

          // Store a copy of the device object in the `accessory.context` property,
          // which can be used to store any data about the accessory you may need.
          accessory.context.device = device;

          // Create the accessory handler for the newly create accessory
          new IndoorUnitAccessory(this, accessory);

          // Link the accessory to your platform
          this.api.registerPlatformAccessories(PLUGIN_NAME, PLATFORM_NAME, [accessory]);
        }
      }

      // At this point, we set up all devices from Comfort Cloud, but we did not unregister
      // cached devices that do not exist on the Comfort Cloud account anymore.
      for (const cachedAccessory of this.accessories) {

        if (cachedAccessory.context.device) {
          const guid = cachedAccessory.context.device.deviceGuid;
          const cloudDevice = cloudDevices.find(device => device.deviceGuid === guid);

          if (cloudDevice === undefined) {
            // This cached devices does not exist on the Comfort Cloud account (anymore).

            this.log.info(`Removing device '${cachedAccessory.displayName}' (${guid}) `
              + 'because it does not exist on the Comfort Cloud account or has been excluded in plugin config.');

            this.api.unregisterPlatformAccessories(PLUGIN_NAME, PLATFORM_NAME, [cachedAccessory]);
          }
        }
      }
    } catch (error) {
      this.log.error('An error occurred during device discovery. '
        + 'Turn on debug mode for more information.');
      this.log.debug(error);
    }
  }
}