"use strict";

const Promise = require("bluebird");
const pEvent = require("p-event");
const pStream = require("p-stream");

module.exports = function fetch(client, args, options = {}) {
	return new Promise((resolve, reject) => {
		let attributeResults = [];
		let bodyInfoResults = [];
		let bodyPromises = [];

		let fetchOp = client.seq.fetch(... args);
	
		fetchOp.on("end", () => {
			resolve(Promise.try(() => {
				if (options.onEnd != null) {
					return options.onEnd();
				}
			}).then(() => {
				return Promise.all(bodyPromises);
			}).then((bodies) => {
				return {
					attributeResults,
					bodyInfoResults,
					bodies
				};
			}));
		});

		fetchOp.on("message", (message) => {
			message.on("attributes", (attributes) => {
				attributeResults.push(attributes);
			});

			message.on("body", (bodyStream, info) => {
				bodyInfoResults.push(info);

				bodyPromises.push(pStream(bodyStream));
			});
		});
		
		pEvent(fetchOp, "error").then(reject);
	});
};