script.esnext.video.js

'use strict'

const fetchOption = {
	headers: {
		'Content-Type' : 'application/json'
	},
	mode: 'cors'
};

$('form').on('submit', function(e) {
	e.preventDefault();

	let types = $('input[type=text]').val().replace(/\s/g,'');
	types = types.split(',');

	let trainerTypeCalls = types.map( elem  => {
		return fetch(`http://pokeapi.co/api/v2/type/${elem}/`, fetchOption)
	});

	getPromiseData(trainerTypeCalls)
		.then( result => {
			console.log(result);
			getDoubleDamagePokemon(result);
		});

});

function getDoubleDamagePokemon(pokemonTypes) {

	pokemonTypes = pokemonTypes
		.map( types => {
			return types.damage_relations.double_damage_from
		})
		.reduce(flatten, [])
		.map( type => {
			return fetch(type.url, fetchOption)
		});

	getPromiseData(pokemonTypes)
		.then(results => {
			console.log(results);
			buildTeam(results);
		});

}

function buildTeam(pokemons) {
	let team = [];
	pokemons = pokemons.map( pokemon  => {
		return pokemon.pokemon;
	})
	.reduce(flatten, [])
	.map( pokemon => pokemon.pokemon );

	for(let i = 0; i < 6; i++) {
		team.push( getRandomPokemon(pokemons) );
	}

	team = team.map(pokemon =>  {
		return fetch(pokemon.url,fetchOption);
	});

	getPromiseData(team)
		.then(pokemonData => {
			displayPokemon(pokemonData);
		});
}

function getRandomPokemon(pokemonArray) {
	return pokemonArray[ Math.floor(Math.random() * pokemonArray.length) ];
}

const flatten = (a,b) => [...a,...b];

function getPromiseData(promisesArray) {
	return new Promise((resolve,reject) => {
		Promise.all(promisesArray)
			.then(res => {
				return res.map( type => type.json() );
			})
			.then(res => {
				Promise.all(res)
					.then(resolve);
			})
			.catch(reject);
	});
}

function displayPokemon(pokemon) {
	// loop through and display the pokemon!
	pokemon.forEach( poke => {
		var $container = $('<div>').addClass('pokemon');
		var $image = $('<img>').attr('src',`http://pokeapi.co/media/img/${poke.id}.png`);
		var $title = $('<h2>').text(poke.name);
		$container.append($image,$title);
		$('.poke-container').append($container);
	});
}