#!/usr/bin/env node

'use strict';

// MODULES //

var fs = require( 'fs' );

var path = require( 'path' );

var spawn = require( 'child_process' ).spawn;

var parseArgs = require( 'minimist' );

var notifier = require( 'update-notifier' );

var pkg = require( './../package.json' );

var opts = require( './opts.json' );

var commands = require( './commands.json' );

// FUNCTIONS //

/**

* Prints usage information.

*

* @private

* @example

* help();

* // => '...'

*/

function help() {

var fpath = path.join( __dirname, 'usage.txt' );

fs.createReadStream( fpath )

.pipe( process.stdout )

.on( 'close', onClose );

function onClose() {

process.exit( 0 );

}

} // end FUNCTION help()

/**

* Prints the package version.

*

* @private

* @example

* version();

* // => '#.#.#'

*/

function version() {

var msg = pkg.version.toString()+'\n';

process.stdout.write( msg, 'utf8' );

process.exit( 0 );

} // end FUNCTION version()

/**

* Callback invoked upon encountering an error while running a command.

*

* @private

* @param {Error} error - error object

* @throws {Error} unexpected error

*/

function onError( error ) {

throw error;

} // end FUNCTION onError()

// VARIABLES //

var args1;

var args2;

var proc;

var cmd;

var i;

// INIT //

process.title = pkg.name;

process.stdout.on( 'error', process.exit );

// PACKAGE UPDATES //

notifier( { 'pkg': pkg } ).notify();

// ARGUMENTS //

args1 = parseArgs( process.argv.slice( 2 ), opts );

if ( args1.version ) {

return version();

}

cmd = args1._[ 0 ];

// MAIN //

opts = {

'cwd': process.cwd(),

'env': process.env,

'stdio': 'inherit'

};

if ( cmd === 'help' ) {

if ( args1._[1] === void 0 ) {

return help();

}

cmd = commands[ args1._[1] ];

if ( cmd === void 0 ) {

throw new Error( 'invalid argument. Unrecognized/unsupported command. Value: `' + cmd + '`.' );

}

args2 = new Array( 2 );

args2[ 0 ] = cmd;

args2[ 1 ] = '--help';

} else {

if ( cmd === 'repl' ) {

args2 = new Array( 1 );

args2[ 0 ] = commands[ cmd ];

} else {

throw new Error( 'invalid argument. Unrecognized/unsupported command. Value: `' + cmd + '`.' );

}

for ( i = 1; i < args1._.length; i++ ) {

args2.push( args1._[ i ] );

}

}

proc = spawn( 'node', args2, opts );

proc.on( 'error', onError );