siimee/frontend/src/services/chat.service.js

import PubNub from 'pubnub'

// custom services 
import {fetchMembershipsByProfileId} from '../services/grouping.service'

/**
 * Provider method holder
 * We always reference this object so
 * we don't have to hardcode provider specific
 * methods for doing chat things.
 *
 * This gets overloaded later in the program
 */
const providerMethods = {
    publish: () => console.error('no provider publish method set'),
    subscribe: () => console.error('no provider subscribe method set'),
    listen: () => console.error('no provider listen method set'),
}

/**
 * Breaking out as much pubnub specific flavor
 */
const setupPubnub = async uuid => {
    const publishKey = 'pub-c-73f35484-396f-47ff-b4b6-45bed079fd3b'
    const subscribeKey = 'sub-c-6cb7f5d0-94e2-11ec-b249-a68c05a281ab'
    if (!uuid) return console.error('no pubnub uuid set')

    const pubnubClient = await new PubNub({
        publishKey: publishKey,
        subscribeKey: subscribeKey,
        logVerbosity: false,
        uuid,
    })
    // Pass pubnub specific methods to our placeholder obj
    providerMethods['publish'] = pubnubClient.publish
    providerMethods['subscribe'] = pubnubClient.subscribe
    providerMethods['listen'] = pubnubClient.addListener

    return pubnubClient
}

class ChatMessage {
    constructor({ title, description }) {
        ;(this.title = title), (this.description = description)
    }
}

const testMessage = new ChatMessage({
    title: 'testing',
    description: 'hello world!',
})
const MAIN_CHANNEL = 'Channel-Barcelona'

/** Singleton that holds all our chat information */
class Chatter {
    /**
     * Create our chatter instance
     * @return {Chatter} our chatter instance object
     */
    constructor() {
        // Map of each active chat
        // * this is where we will store all of our groupings on from the backend on user login...
        this.groupings = {}

        // Our pubnub instance
        this.provider = null

        // UUID used to identify unique users
        this.uuid = null

        // Setup the main channel
        //  subscriptions array will be built dynamically from the "this.groupings" object
        this.subscriptions = [MAIN_CHANNEL, 'Channel-LosAngeles']
        this.listeners = {
            status: async e => {
                await this.publish(this.subscriptions[2], testMessage)
                if (e.category !== 'PNConnectedCategory') return
            },
            message: this._onMessage,
            presence: this._onPresence,
        }
    }
    /**
     * Callback that fires on every message
     * @param {event} e
     */
    async _onMessage(e) {
        if (e.message) {
            console.log(
                `received message: ${e.message.title} - ${e.message.description}`,
                e,
            )
        }
    }
    async _onPresence(e) {
        return
    }
    async setup(uuid) {
        this.uuid = `${uuid}`
        this.provider = await setupPubnub(this.uuid)
            
        //  step 1: build the this.groupings object from the backend
        // ? .then() to wait for the groupings to be fetched before subscribing to channels
        this.getGroupingsByProfileId(this.uuid).then(() => {
            this._listenFor({ listeners: this.listeners })
            this._subscribe(this.subscriptions)
        })
        
        console.log('this.subscriptions', this.subscriptions)
       
    }
    /**
     * Send a message to a channel
     * example = new ChatMessage({ title: 'example', description: 'ni' })
     * Facade so we can hide provider specific methods
     * @param {string} channel
     * @param {ChatMessage} message
     * @return {object} timestamp
     */
    async publish(channel, message) {
        console.log('publishing message to channel:', channel)
        return await providerMethods['publish']({ channel, message })
    }
    /**
     * Subscribe to a channels
     * Facade so we can hide provider specific methods
     * @param {array} channels
     */
    _subscribe(channels) {
        providerMethods['subscribe']({ channels })
    }
    /**
     * Listen to events and set callbacks
     * Facade so we can hide provider specific methods
     */
    _listenFor({ listeners }) {
        providerMethods['listen'](listeners)
    }
    
    //  step 2: build the this.subscriptions array from the this.groupings object
    // fetch all groupings for this profile and then store them in the chatter groupings object for reference
    async getGroupingsByProfileId(profileId) {
        console.log('fetching groupings for profileId:', profileId)
        const groupings = await fetchMembershipsByProfileId(profileId)
        this.groupings = groupings
        this.createChannelNamesByGroupings(this.groupings)
    }
    // building a list of channel names from the groupings object.grouping_name
    createChannelNamesByGroupings(groupings) {
        groupings.forEach(item => {
            this.subscriptions.push(item.grouping_name)
        });
        
        
    }
}

export { Chatter }