const realpath = require('fs').realpath;
const stat = require('fs').stat;

function fileExists(file) {
    return new Promise((resolve, reject) => {
        if (file === undefined) {
            reject('can not check the existence of an undefined file');
        }
        resolvePath(file)
            .then((path) => {
                stat(path, (err, stats) => {
                    if (err) {
                        reject(err);
                    }
                    resolve({ path, stats });
                })
            })
            .catch(reject);
    });
}

function resolvePath(file) {
    return new Promise((resolve, reject) => {
        if (file === undefined) {
            reject('can not resolve a path to an undefined file');
        }
        realpath(file, (err, resolvedPath) => {
            if (err) {
                reject('resolving path \'' + file + '\' encountered an error >>> ' + err);
            }
            resolve(resolvedPath);
        })
    });
}

module.exports = {
    fileExists,
    resolvePath
};