import {
  API,
  APIEvent,
  Categories,
  Characteristic,
  DynamicPlatformPlugin,
  Logger,
  PlatformAccessory,
  PlatformConfig,
  Service,
} from 'homebridge';

import { PLATFORM_NAME, PLUGIN_NAME } from './settings';
import { PanelAccessory } from './accessories/panel';
import G4S from 'g4s';

export class G4SPlatform implements DynamicPlatformPlugin {
  public readonly Service: typeof Service = this.api.hap.Service;
  public readonly Characteristic: typeof Characteristic =
    this.api.hap.Characteristic;

  public readonly accessories: PlatformAccessory[] = [];
  public readonly G4S: G4S;

  constructor(
    public readonly log: Logger,
    public readonly config: PlatformConfig,
    public readonly api: API,
  ) {
    this.G4S = new G4S(this.config.username, this.config.password);
    this.log.debug('Finished initializing platform:', this.config.name);

    // 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, async () => {
      log.debug('Executed didFinishLaunching callback');
      // run the method to discover / register your devices as accessories
      await this.discoverDevices();
    });
  }

  /**
   * This function is invoked when homebridge restores cached accessories from disk at startup.
   * It should be used to setup event handlers for characteristics and update respective values.
   */
  configureAccessory(accessory: PlatformAccessory) {
    this.log.info('Loading accessory from cache:', accessory.displayName);

    // add the restored accessory to the accessories cache so we can track if it has already been registered
    this.accessories.push(accessory);
  }

  /**
   * Accessories must only be registered once, previously created accessories
   * must not be registered again to prevent "duplicate UUID" errors.
   */
  async discoverDevices() {
    const panelId = (await this.G4S.getPanel()).PanelId;

    // 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(panelId.toString());

    // see 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) {
      // the accessory already exists
      this.log.info(
        'Restoring existing accessory from cache:',
        existingAccessory.displayName,
      );

      // 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
      // this is imported from `platformAccessory.ts`
      new PanelAccessory(this, existingAccessory);
    } else {
      const displayName = `Panel: ${panelId}`;
      // the accessory does not yet exist, so we need to create it
      this.log.info('Adding new accessory:', displayName);

      // create a new accessory
      const accessory = new this.api.platformAccessory(
        displayName,
        uuid,
        Categories.SECURITY_SYSTEM,
      );

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

      // create the accessory handler for the newly create accessory
      // this is imported from `platformAccessory.ts`
      new PanelAccessory(this, accessory);

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