"use strict";

const Promise = require("bluebird");
const execAll = require("execall");
const execBinary = require("../exec-binary");

function createNamespaceParser() {
	return {
		supportsStreams: false,
		parse: function (input) {
			return {
				namespaces: execAll(/^\[\s*[0-9]+\]:(?:(0)|0x([0-9A-F]+))$/gm, input)
					.map((match) => {
						let [ idLiteral, idHex ] = match.sub;

						if (idLiteral != null) {
							/* NOTE: This is a special case for when the value is exactly 0 - and maybe there are others too, hence still doing a parseInt, so we can easily change the regex later if needed:
								https://stackoverflow.com/questions/11922876/what-does-a-hash-sign-do-in-printf#comment15879638_11922887
								https://github.com/linux-nvme/nvme-cli/blob/f9ebefe27b0596006d76d58f3219a9fc12e88664/nvme.c#L979
							*/
							return parseInt(idLiteral);
						} else {
							return parseInt(idHex, 16);
						}
					})
			};
		}
	};
}

module.exports = {
	listNamespaces: function ({ devicePath }) {
		return Promise.try(() => {
			return execBinary("nvme", [ "list-ns", devicePath ])
				.asRoot()
				.expectOnStdout(createNamespaceParser())
				.execute();
		}).then((output) => {
			return output.result.namespaces;
		});
	}
};