hashfile node utility for shell

hashfile

#!/usr/bin/env node

/*

Usage in shell: 

hashfile [--sha1|--md5] <file> [--eq <hash2>|--eqf <file2>]

Examples:
> hashfile package.json                                    => print sha1 hash of package.json
> hashfile --md5 package.json                              => print md5 hash of package.json
> hashfile package.json --eq lkm43lkm4lr35n4jn3n34jn5k     => true|false
> hashfile package.json --eqf ../../package.json           => true|false

*/

'use strict';

var path = require('path'),
    fs = require('fs'),
    hash_file = require('hash_file');

var basedir = process.cwd();

var alg = process.argv[2],
    hash, file, i = 3, hash2, file2;
    
function check() {
    if (hash && hash2) {
        console.log(hash === hash2);
    }
}

switch (alg) {
    case '--sha1':
    case '--md5':
        alg = alg.substring(2);
        file = process.argv[3];
        i = 4;
        break;
    default:
        file = alg;
        alg = 'sha1';
        break;
}

switch (process.argv[i]) {
    case '--eq':
        hash2 = process.argv[i + 1];
        break;
    case '--eqf':
        file2 = process.argv[i + 1];
        break;
}

file = path.resolve(basedir, file);
if (!fs.existsSync(file)) {
    console.error('File "' + file + '" does not exist.');
    return;
}
if (file2) {
    file2 = path.resolve(basedir, file2);
    if (!fs.existsSync(file2)) {
        console.error('File "' + file2 + '" does not exist.');
        return;
    }
    hash_file(file, alg, function(error, res) {
        if (error) {
            console.error(error.message || error);
            return;
        }
        hash = res;
        check();
    });
    hash_file(file2, alg, function(error, res) {
        if (error) {
            console.error(error.message || error);
            return;
        }
        hash2 = res;
        check();
    });
}
else {
    hash_file(file, alg, function(error, res) {
        if (error) {
            console.error(error.message || error);
            return;
        }
        console.log(hash2 ? hash2.toLowerCase() === res : res);
    });
}