import {
  CreateSubscriptionRequest,
  SubscriptionInfo,
} from '@rc-ex/core/lib/definitions';

import WebSocketExtension from './index';
import {WsgEvent, WsgMeta} from './types';
import Utils from './utils';

class Subscription {
  wse: WebSocketExtension;
  eventFilters: string[];
  eventListener: (event: WsgEvent) => void;
  timeout?: NodeJS.Timeout;
  enabled = true;

  constructor(
    wse: WebSocketExtension,
    eventFilters: string[],
    callback: (event: {}) => void
  ) {
    this.wse = wse;
    this.eventFilters = eventFilters;
    this.eventListener = (event: WsgEvent) => {
      const [meta, body]: [WsgMeta, {subscriptionId: string}] =
        Utils.splitWsgData(event.data);
      if (
        this.enabled &&
        meta.type === 'ServerNotification' &&
        body.subscriptionId === this.subscriptionInfo!.id
      ) {
        callback(body);
      }
    };
    this.setupWsEventListener();
  }

  setupWsEventListener() {
    this.wse.ws.addEventListener('message', this.eventListener);
  }

  get requestBody(): CreateSubscriptionRequest {
    return {
      deliveryMode: {transportType: 'WebSocket'},
      eventFilters: this.eventFilters,
    };
  }

  _subscriptionInfo?: SubscriptionInfo;
  get subscriptionInfo(): SubscriptionInfo | undefined {
    return this._subscriptionInfo;
  }
  set subscriptionInfo(_subscription) {
    this._subscriptionInfo = _subscription;
    if (this.timeout) {
      global.clearTimeout(this.timeout);
      this.timeout = undefined;
    }
    if (_subscription) {
      this.timeout = global.setTimeout(() => {
        this.refresh();
      }, ((_subscription.expiresIn ?? 900) - 120) * 1000);
    }
  }

  async subscribe() {
    this.subscriptionInfo = (
      await this.wse.request<SubscriptionInfo>(
        'POST',
        '/restapi/v1.0/subscription',
        this.requestBody
      )
    ).data;
  }

  async refresh() {
    if (!this.subscriptionInfo) {
      return;
    }
    try {
      this.subscriptionInfo = (
        await this.wse.request<SubscriptionInfo>(
          'PUT',
          `/restapi/v1.0/subscription/${this.subscriptionInfo!.id}`,
          this.requestBody
        )
      ).data;
    } catch (e) {
      if (e.response && e.response.status === 404) {
        // subscription expired
        await this.subscribe();
      }
    }
  }

  async revoke() {
    if (!this.subscriptionInfo) {
      return;
    }
    if (this.timeout) {
      global.clearTimeout(this.timeout);
      this.timeout = undefined;
    }
    try {
      await this.wse.request<SubscriptionInfo>(
        'DELETE',
        `/restapi/v1.0/subscription/${this.subscriptionInfo!.id}`
      );
    } catch (e) {
      if (e.response && e.response.status === 404) {
        // ignore
        if (this.wse.options.debugMode) {
          console.debug(
            `Subscription ${
              this.subscriptionInfo!.id
            } doesn't exist on server side`
          );
        }
      } else if (e.response && e.response.status === 401) {
        // ignore
        if (this.wse.options.debugMode) {
          console.debug('Token invalid when trying to revoke subscription');
        }
      } else {
        throw e;
      }
    }
    this.subscriptionInfo = undefined;
    this.enabled = false;
    this.wse.ws.removeEventListener('message', this.eventListener);
  }
}

export default Subscription;