/*
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */

/*
 * Copyright 2016 Joyent, Inc.
 *
 * `triton instance ssh ...`
 */

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

var common = require('../common');


function do_ssh(subcmd, opts, args, callback) {
    var self = this;

    if (opts.help) {
        this.do_help('help', {}, [subcmd], callback);
        return;
    } else if (args.length === 0) {
        callback(new Error('invalid args: ' + args));
        return;
    }

    var cli = this.top;
    var id = args.shift();

    var user = 'root';
    var i = id.indexOf('@');
    if (i >= 0) {
        user = id.substr(0, i);
        id = id.substr(i + 1);
    }

    cli.tritonapi.getInstance(id, function (err, inst) {
        if (err) {
            callback(err);
            return;
        }

        var ip = inst.primaryIp;
        if (!ip) {
            callback(new Error('primaryIp not found for instance'));
            return;
        }

        args = ['-l', user, ip].concat(args);

        /*
         * By default we disable ControlMaster (aka mux, aka SSH connection
         * multiplexing) because of
         * https://github.com/joyent/node-triton/issues/52
         *
         */
        if (!opts.no_disable_mux) {
            /*
             * A simple `-o ControlMaster=no` doesn't work. With just that
             * option, a `ControlPath` option (from ~/.ssh/config) will still
             * be used if it exists. Our hack is to set a ControlPath we
             * know should not exist. Using '/dev/null' wasn't a good
             * alternative because `ssh` tries "$ControlPath.$somerandomnum"
             * and also because Windows.
             */
            var nullSshControlPath = path.resolve(
                cli.tritonapi.config._configDir, 'tmp', 'nullSshControlPath');
            args = [
                '-o', 'ControlMaster=no',
                '-o', 'ControlPath='+nullSshControlPath
            ].concat(args);
        }

        self.top.log.info({args: args}, 'forking ssh');
        var child = spawn('ssh', args, {stdio: 'inherit'});
        child.on('close', function (code) {
            /*
             * Once node 0.10 support is dropped we could instead:
             *      process.exitCode = code;
             *      callback();
             */
            process.exit(code);
        });
    });
}

do_ssh.options = [
    {
        names: ['help', 'h'],
        type: 'bool',
        help: 'Show this help.'
    },
    {
        names: ['no-disable-mux', 'M'],
        type: 'bool',
        help: 'Do *not* disable usage of SSH connection multiplexing. Using '
            + 'this option might result in hitting a known issue where '
            + 'command output is lost. See below.'
    }
];
do_ssh.help = [
    /* BEGIN JSSTYLED */
    'SSH to the primary IP of an instance',
    '',
    'Usage:',
    '     {{name}} ssh [-h] [-M] <inst> [<ssh-arguments>]',
    '',
    '{{options}}',
    'Where <inst> is the name, short ID or ID of a given instance. Note that',
    'the <inst> argument must come before any `ssh` options or arguments.',
    '',
    'There is a known issue with SSH connection multiplexing (a.k.a. ',
    'ControlMaster, mux) where stdout/stderr is lost. As a workaround, `ssh`',
    'is spawned with options disabling ControlMaster. You may use the `-M`',
    'option to not disable ControlMaster but, with node >=0.12, you will lose',
    'stdout/stderr output. See <https://github.com/joyent/node-triton/issues/52>',
    'for details.'
    /* END JSSTYLED */
].join('\n');

do_ssh.interspersedOptions = false;

// Use 'file' to fallback to the default bash completion... even though 'file'
// isn't quite right.
do_ssh.completionArgtypes = ['tritoninstance', 'file'];

module.exports = do_ssh;