'use strict';

var UI      = require('ember-cli/lib/ui');
var through = require('through');
var Promise = require('ember-cli/lib/ext/promise');

module.exports = MockUI;
function MockUI() {
    this.output = '';

    UI.call(this, {
        inputStream: through(),
        outputStream: through(function(data) {
            this.output += data;
        }.bind(this))
    });
}

MockUI.prototype = Object.create(UI.prototype);
MockUI.prototype.constructor = MockUI;
MockUI.prototype.clear = function(){
    this.output = '';
};

MockUI.prototype.waitForPrompt = function() {
    if (!this._waitingForPrompt) {
        var promise, resolver;
        promise = new Promise(function(resolve){
            resolver = resolve;
        });
        this._waitingForPrompt = promise;
        this._promptResolver = resolver;
    }
    return this._waitingForPrompt;
};

MockUI.prototype.prompt = function(opts, cb) {
    if (this._waitingForPrompt) {
        this._waitingForPrompt = null;
        this._promptResolver();
    }
    return UI.prototype.prompt.call(this, opts, cb);
};