das-home-api/modules/SKU/index.js

const express = require('express');
const path = require('path');

const CrudModule = require('klapi/base/CrudModule');
const OneToOne = require('klapi/base/OneToOne');
const RepositorySystem = require('klapi/systems/RepositorySystem');
const RoutingSystem = require('klapi/systems/RoutingSystem');
const Actions = require('klapi/systems/ActionSystem');
var db = require("../../db.js");
//const FilterService = require(;'')
var knex = require('knex')(db);
let CategoriesScheme = {
	fields: [
		{
			key: "sku",
			type: "string",
			unique: true,
			keyLength: 50
		},
		{
			key: "link",
			type: "text"
		},
		{
			key: "price",
			type: "decimal"
		},
		{
			key: "title",
			type: "text"
		},
		{
			key: "category",
			type: "text"
		}
	]
};

class SKUModule extends CrudModule {
	constructor(){
		super('/skus', [1,0,1,1,0], 'SKU', '', );
		this.repository = RepositorySystem.create('SKU', CategoriesScheme);
		this.setRepo(this.repository);

		this.categories = new OneToOne('Categories', 'SKU');
		this.init();
		Actions.on('getSKU', (sku) => {
			return this.selectSKU(sku);
	 	})
		Actions.on('ArraygetSKU',(skus) => {
			return this.selectSKU(skus);
		})
		Actions.on('getProducts',(product) => {
			return this.repository.get('sku',product.SKU)
			.then((sku) => {
				product['title'] = sku[0].title;
				return product;
			})
		})
		Actions.on('ArraygetProducts',(product) => {
			return this.repository.get('sku',product.SKU)
			.then((sku) => {
				product['title'] = sku[0].title;
				return product;
			})
		})
	}
	init(){
		let routes = [
			{	
				type:"custom",
				method:"get",
				endpoint:"/notifications",
				customFn: (req,res) => {

					this.notifications()
					.then((prod) => {
						res.send(prod)
					})
					.catch((e) => {
						console.log("errio form here",e)
						res.send(e);
					})
				}
			}
		];
		RoutingSystem.loadRoutes(routes, this.router);
	}
		
	selectSKU(product){
		return knex("Products").select('price').count('id as Shops').where({sku:product.sku}).groupBy('price').orderBy('Shops','desc')//
		.then((suggested_item) => {
			let price = suggested_item[0].price;
			let paravates = suggested_item.filter((item) => item.price < price )
			let number_of_paraviaseis = paravates.reduce((accumulator,item) => accumulator+item.Shops,0)
			product['suggested_price'] = price;
			product['paraviaseis'] = number_of_paraviaseis;
			return product;
		})
		
	}

	notifications(){
	

		return knex('SKU').select('*').limit(48)
		.then((skus) =>  Promise.all(skus.map((sku) => {
				let suggested_price;
				return this.selectSKU(sku)
				.then((sku) => {
					suggested_price = sku['suggested_price'];
					return sku['suggested_price']})
				.then((suggested_price) =>{
				return  knex('Products').select("*").where('price','<',suggested_price).where({sku:sku.sku}) })
				.then((paravates) => paravates.map((item) => {
						item['actual_price'] = suggested_price;
						item['discount'] = (suggested_price - item.price)/suggested_price;
						item.link = sku.link;
						return item;
				}))
				.then((products) => Actions.emitArray('getProducts',products))
				
			}))
			.then((result) =>  [].concat.apply([], result))
		)
		
	}




}

module.exports = SKUModule;