(function(){
  var File = require('file');
  var OS = require('os');
  exports.run = function(args) {
    args.shift();
    if (args.length) {
      return require(File.absolute(args[0]));
    }
    while (true) {
      try {
        system.stdout.write('cs> ').flush();
        var result = exports.cs_eval(require('readline').readline());
        if (result !== undefined) {
          print(result);
        }
      } catch (e) {
        print(e);
      }
    }
  };
  // executes the coffee-script Ruby program to convert from CoffeeScript to Objective-J.
  // eventually this will hopefully be replaced by a JavaScript program.
  var coffeePath = File.path(module.path).dirname().dirname().join('bin', 'coffee-script');
  exports.compileFile = function(path) {
    var coffee = OS.popen([coffeePath, "--print", "--no-wrap", path]);
    if (coffee.wait() !== 0) {
      system.stderr.print(coffee.stderr.read());
      throw new Error("coffee-script compile error");
    }
    return coffee.stdout.read();
  };
  exports.compile = function(source) {
    var coffee = OS.popen([coffeePath, "--eval", "--no-wrap"]);
    coffee.stdin.write(source).flush().close();
    if (coffee.wait() !== 0) {
      system.stderr.print(coffee.stderr.read());
      throw new Error("coffee-script compile error");
    }
    return coffee.stdout.read();
  };
  // these two functions are equivalent to objective-j's objj_eval/make_narwhal_factory.
  // implemented as a call to coffee and objj_eval/make_narwhal_factory
  exports.cs_eval = function(source) {
    init();
    return eval(exports.compile(source));
  };
  exports.make_narwhal_factory = function(path) {
    init();
    var code = exports.compileFile(path);
    var factoryText = "function(require,exports,module,system,print){" + code + "/**/\n}";
    if (system.engine === "rhino") {
      return Packages.org.mozilla.javascript.Context.getCurrentContext().compileFunction(global, factoryText, path, 0, null);
    } else {
      // eval requires parenthesis, but parenthesis break compileFunction.
      return eval("(" + factoryText + ")");
    }
  };
  var init = function() {
    // make sure it's only done once
    init = function() {
    };
    return init;
  };
})();