/**
 * benchmark: find a product in product list
 * using: for vs forEach vs find
 */

const microtime = require('microtime');

var products = require('../../data/products.json');
if (products.length == 0) {
    const prepare = require('../pieces/prepare.js');
    prepare.load_products(
        'https://storage.googleapis.com/pythia-files/uploads/json/emarket-products.json'
    );
}



var selected = [];
products.forEach( pr => {
    if (Math.floor(Math.random() * 100) > 85) {
        selected.push(pr.id);
    }
});


function compare() {

    let n = 4;

    var f0 = microtime.nowDouble();
    for(i=0 ; i < n ; i++) byFor();
    var f1 = microtime.nowDouble();
    // 
    var e0 = microtime.nowDouble();
    for(i=0 ; i < n ; i++) byEach();
    var e1 = microtime.nowDouble();
    //
    var b0 = microtime.nowDouble();
    for(i=0 ; i < n ; i++) byFind();
    var b1 = microtime.nowDouble();

    return {
        n: n,
        
        for: f1-f0,
        items_for: byFor(),

        each: e1-e0,
        items_each: byEach(),

        find: b1-b0,
        items_find: byFind(),

        sel: selected,
    }
}


function byFor() {
    var items = [];
    var notFound = [];
    var found;
    selected.forEach( id => {
        found = false;
        for(i = 0; i < products.length; i++) {
            if (products[i].id == id) {
                items.push(products[i]);
                found = true;
                break;
            }
        }
        if (!found) notFound.push(id)

    })
    return {items: items, nf: notFound};
}


function byEach() {
    var items = [];
    var notFound = [];
    var found;
    selected.forEach( id => {
        found = false;
        products.forEach( pr => {
            if (pr.id == id) {
                items.push(pr);
                found = true;
            }
        });
        if (!found) notFound.push(id)
    });
    return {items: items, nf: notFound};
}

function byFind() {
    var items = [];
    var notFound = [];
    var result;
    selected.forEach( id => {
        found = false;
        result = products.find((pr) => pr.id == id);
        if (result === undefined) notFound.push(id)
        else items.push(result);
    });
    return {items: items, nf: notFound};
}

module.exports = {
    compare,
    byFor
}