//Includes

import { BUError } from './BUError'

import { BUCollection } from './BUCollection'

import { BUDocument } from './BUDocument'

export class BUCollectionManager {

timer: any

//Singleton

private static _instance: BUCollectionManager

public static get instance(){ return this._instance || (this._instance = new this()) }

private constructor(){ this.uploadAllPerform() }

//Store collections

collections: { [key: string]: BUCollection } = {}

//Upload timer interval

interval = 2000.0

//Events

error: (collection: BUCollection, error: BUError) => void

success: (collection: BUCollection, uploaded: number) => void

//Create collections from array of name

create(names: string[]){

for (const name of names){

//Check name doesn't exists in collections

if (Object.keys(this.collections).includes(name)){

continue

}

//Create new collection if name doesnt exist

this.collections[name] = new BUCollection(name)

}

}

//Convenience method for adding a document to a collection and creating the collection if non-existant

push(collection: string, document: BUDocument | Object){

//Create document if object given

let data

if (document instanceof Object){

document = new BUDocument(data)

}else{

data = document

}

//Check whether document exists and create

if (!Object.keys(this.collections).includes(name)){

this.collections[collection] = new BUCollection(collection)

}

//Add document to collection

this.collections[collection].push(data)

}

//Push documents in all collections to backend server

private uploadAllPerform(timer?: any){

this.uploadAll()

//Create timer to push all collections every x seconds

if (this.interval > 0){

setTimeout(() => {

this.uploadAllPerform()

}, this.interval)

}

}

uploadAll(){

//Push all collections

Object.keys(this.collections).forEach(key => {

const collection = this.collections[key]

collection.upload((code: BUError) => {

//Notify error

if (this.error !== undefined){

this.error(collection, code)

}

}, (count: number) => {

//Notify success

if (this.success !== undefined){

this.success(collection, count)

}

})

})

}

}