const path = (path, obj) => path.reduce((result, segment) => result && result[segment], obj);

const compose = (...fns) => fns.reduce((f, g) => (...args) => f(g(...args)));

const getText = ctx => path(['update', 'message', 'text'], ctx) || '';

const removeCommand = cmd => text => text.replace(`/${cmd}`, '').trim();

const extractCommandText = cmd => ctx =>
	compose(
		removeCommand(cmd),
		getText,
	)(ctx);

module.exports = {
	path,
	compose,
	getText,
	extractCommandText,
};