import { hook, Mixin } from './mixin';
import { RealtimeClient } from '../realtime.client';
import { Topics } from '../../constants';
import { tryUnzipAsync } from '../../shared';
import { GraphQlMessage, ParsedMessage } from '../parsers';
import { QueryIDs } from '../subscriptions';
import { RealtimeSubDirectDataWrapper } from '../messages';
import { IllegalStateError } from 'mqtts';

export class RealtimeSubMixin extends Mixin {
   apply(client: RealtimeClient): void {
      hook(client, 'connect', {
         post: () => {
            if (!client.mqtt) {
               throw new IllegalStateError('No mqtt client created');
            }
            client.mqtt.listen(
               {
                  topic: Topics.REALTIME_SUB.id,
                  transformer: async ({ payload }) =>
                     Topics.REALTIME_SUB.parser.parseMessage(Topics.REALTIME_SUB, await tryUnzipAsync(payload)),
               },
               data => this.handleRealtimeSub(client, data),
            );
         },
      });
   }

   private handleRealtimeSub(client: RealtimeClient, { data, topic: messageTopic }: ParsedMessage<GraphQlMessage>) {
      const { message } = data;
      client.emit('realtimeSub', { data, topic: messageTopic });
      if (typeof message === 'string') {
         this.emitDirectEvent(client, JSON.parse(message));
      } else {
         const { topic, payload, json } = message;
         switch (topic) {
            case 'direct': {
               this.emitDirectEvent(client, json);
               break;
            }
            default: {
               const entries = Object.entries(QueryIDs);
               const query = entries.find(e => e[1] === topic);
               if (query) {
                  client.emit(query[0] as keyof typeof QueryIDs, json || payload);
               }
            }
         }
      }
   }

   private emitDirectEvent(client: RealtimeClient, parsed: any): void {
      parsed.data = parsed.data.map((e: any) => {
         if (typeof e.value === 'string') {
            e.value = JSON.parse(e.value);
         }
         return e;
      });
      parsed.data.forEach((data: RealtimeSubDirectDataWrapper) => client.emit('direct', data));
   }

   get name(): string {
      return 'Realtime Sub';
   }
}