'use strict';

var fs = require('fs');
var path = require('path');
var util = require('util');
var dbg = require('debug');

// process.env.TABTAB_DEBUG = process.env.TABTAB_DEBUG || '/tmp/tabtab.log';

var out = process.env.TABTAB_DEBUG ? fs.createWriteStream(process.env.TABTAB_DEBUG, { flags: 'a' }) : null;

module.exports = debug;

// Internal: Facade to debug module, which provides the exact same interface.
//
// The added benefit is with the TABTAB_DEBUG environment variable, which when
// defined, will write debug output to the specified filename.
//
// Usefull when debugging tab completion, as logs on stdout / stderr are either
// shallowed or used as tab completion results.
//
// namespace - The String namespace to use when TABTAB_DEBUG is not defined,
//             delegates to debug module.
//
// Examples
//
//    // Use with following command to redirect output to file
//    // TABTAB_DEBUG="debug.log" tabtab ...
//    debug('Foo');
function 
(namespace) {
  var log = dbg(namespace);
  return function () {
    for (var _len = arguments.length, args = Array(_len), _key = 0; _key < _len; _key++) {
      args[_key] = arguments[_key];
    }

    args = args.map(function (arg) {
      if (typeof arg === 'string') return arg;
      return JSON.stringify(arg);
    });

    out && out.write(util.format.apply(util, args) + '\n');
    out || log.apply(null, args);
  };
}
debug