#!/usr/bin/env node

/**

* @license Apache-2.0

*

* Copyright (c) 2018 The Stdlib Authors.

*

* Licensed under the Apache License, Version 2.0 (the "License");

* you may not use this file except in compliance with the License.

* You may obtain a copy of the License at

*

* http://www.apache.org/licenses/LICENSE-2.0

*

* Unless required by applicable law or agreed to in writing, software

* distributed under the License is distributed on an "AS IS" BASIS,

* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.

* See the License for the specific language governing permissions and

* limitations under the License.

*/

'use strict';

// MODULES //

var path = require( 'path' );

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

var CLI = require( '@stdlib/cli/ctor' );

var parentPath = require( '@stdlib/fs/resolve-parent-path' ).sync;

var readFile = require( '@stdlib/fs/read-file' ).sync;

var hasOwnProp = require( '@stdlib/assert/has-own-property' );

var objectKeys = require( '@stdlib/utils/keys' );

var dirname = require( '@stdlib/utils/dirname' );

var cwd = require( '@stdlib/process/cwd' );

var ENV = require( '@stdlib/process/env' );

var COMMANDS = require( './cli_commands.json' );

// FUNCTIONS //

/**

* Returns command information.

*

* @private

* @param {string} cmd - command

* @returns {(Object|null)} command info

*/

function findCommand( cmd ) {

var i;

for ( i = 0; i < COMMANDS.length; i++ ) {

if ( cmd === COMMANDS[ i ].command ) {

return COMMANDS[ i ];

}

}

return null;

}

/**

* Resolves a CLI file path.

*

* @private

* @param {string} pkgPath - package name/path

* @throws {Error} unable to resolve CLI

* @returns {string} file path

*/

function getPath( pkgPath ) {

var mpath;

var cmds;

var pkg;

if ( /^@stdlib/.test( pkgPath ) ) {

// Resolve a package's main entry point:

mpath = require.resolve( pkgPath );

// Resolve a dependency's path by finding the dependency's `package.json`:

mpath = parentPath( 'package.json', {

'dir': dirname( mpath )

});

// Read the package meta data:

pkg = require( mpath ); // eslint-disable-line stdlib/no-dynamic-require

// Resolve a `bin` field:

if ( !hasOwnProp( pkg, 'bin' ) ) {

throw new Error( 'unexpected error. Unable to resolve command.' );

}

cmds = objectKeys( pkg.bin );

if ( cmds.length === 0 ) {

throw new Error( 'unexpected error. Unable to resolve command.' );

}

// NOTE: assume that the first command is the desired command:

return path.join( dirname( mpath ), pkg.bin[ cmds[ 0 ] ] );

}

// Assume we are given a path relative to the root directory:

return path.resolve( __dirname, '..', pkgPath );

}

// MAIN //

/**

* Main execution sequence.

*

* @private

* @returns {void}

*/

function main() {

var subargs;

var flags;

var keys;

var args;

var opts;

var proc;

var cli;

var cmd;

var key;

var i;

// Create a command-line interface:

cli = new CLI({

'pkg': require( './../package.json' ),

'options': require( './cli_opts.json' ),

'help': readFile( path.resolve( __dirname, 'usage.txt' ), {

'encoding': 'utf8'

})

});

// Get any provided command-line options:

flags = cli.flags();

if ( flags.help || flags.version ) {

return;

}

// Get any provided command-line arguments:

args = cli.args();

// Extract the command:

if ( args.length === 0 ) {

return cli.help();

}

if ( args[ 0 ] === 'help' ) {

if ( args.length === 1 ) {

return cli.help();

}

cmd = findCommand( args[ 1 ] );

if ( cmd === null ) {

return cli.error( new Error( 'invalid argument. Unrecognized/unsupported command. Value: `' + args[ 1 ] + '`.' ) );

}

subargs = [ getPath( cmd.path ), '--help' ];

} else {

cmd = findCommand( args[ 0 ] );

if ( cmd === null ) {

return cli.error( new Error( 'invalid argument. Unrecognized/unsupported command. Value: `' + args[ 0 ] + '`.' ) );

}

subargs = [ getPath( cmd.path ) ];

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

subargs.push( args[ i ] );

}

keys = objectKeys( flags );

for ( i = 0; i < keys.length; i++ ) {

key = keys[ i ];

if (

key === 'h' ||

key === 'help' ||

key === 'V' ||

key === 'version'

) {

continue;

}

subargs.push( '--'+keys[ i ]+'='+flags[ keys[ i ] ] );

}

}

// Define sub-process options:

opts = {

'cwd': cwd(),

'env': ENV,

'stdio': 'inherit'

};

// Invoke the command in a sub-process:

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

proc.on( 'error', onError );

/**

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

*

* @private

* @param {Error} error - error object

*/

function onError( error ) {

cli.error( error );

}

}

main();