// global functions
function isFunction(x) {
  return typeof(x) === 'function';
}

var _toString = Object.prototype.toString;

function isArray(x) {
  return _toString.call(x) === "[object Array]";
}

function isArrayOrNull(x) {
  return x == null || isArray(x);
}

function isString(x) {
  return _toString.call(x) === "[object String]";
}

function isStringOrNull(x) {
  return x == null || isString(x);
}

function isNumber(x) {
  return _toString.call(x) === "[object Number]";
}

function isNumberOrNull(x) {
  return x == null || isNumber(x);
}

function isDefined(x) {
  return typeof(x) !== "undefined";
}

// instantly check iPad or Mac
function isMobile(){
  if(navigator){
    if(navigator.userAgent){
      if(navigator.userAgent.indexOf("Mobile/") != -1){
        return true;
      }
    }
  }
  return false;
}

// define global drikin object
if (!window['drikin']) {
  window['drikin'] = {};
}
if (!window['drikin']['debug']) {
  window['drikin']['debug'] = {};
}
if (!window['drikin']['isDebug']) {
  window['drikin']['isDebug'] = {};
}
if (!window['drikin']['load']) {
  window['drikin']['load'] = {};
}
if (!window['drikin']['loaded']) {
  window['drikin']['loaded'] = {};
}
if (!window['drikin']['setOnLoadCallback']) {
  window['drikin']['setOnLoadCallback'] = {};
}

// create drikin.debug
(function () {
  var isDebug = false;
  var level = 'ALL';
  var body = '';                // caching body element
  var oid = 'drikin_debug';     // element id for debug output
  var out = '';                 // element of debug output
  
  if (typeof drikin.debug !== 'function') {
    drikin.debug = function(flag) {
      return isDebug = flag;
    }
  }
  if (typeof drikin.isDebug !== 'function') {
    drikin.isDebug = function() {
      return isDebug;
    }
  }
  if (typeof drikin.debug.setConsole !== 'function') {
    drikin.debug.setConsole = function(mode) {
      if (isDebug) {      
        if (mode == "full") {        
          out.style.width = document.body.offsetWidth + 'px';
          h = document.body.scrollHeight - 20;
          out.style.height = h + 'px';
        } else if (mode == "leftTop") {
          out.style.top = 0;
          out.style.bottom = null;
          out.style.left = 0;
          out.style.right = null;
        } else if (mode == "leftBottom") {
          out.style.top = null;
          out.style.bottom = 0;
          out.style.left = 0;
          out.style.right = null;
        } else if (mode == "rightTop") {
          out.style.top = 0;
          out.style.bottom = null;
          out.style.left = null;
          out.style.right = 0;
        } else if (mode == "rightBottom") {
          out.style.top = null;
          out.style.bottom = 0;
          out.style.left = null;
          out.style.right = 0;        
        } else if (mode == 'normal') {
          out.style.width = '40%';
          out.style.height = '40%';
        }
      }
    }
  }
  if (typeof drikin.debug.setLevel !== 'function') {
    drikin.debug.setLevel = function(lev) {
      level = lev;
    }
  }
  if (typeof drikin.debug.log !== 'function') {
    drikin.debug.log = function(msg, value, target_level) {
      if (isDebug) {
        if (typeof(value) == 'undefined') {
          value = '';
        }
        if (typeof(target_level) == 'undefined') {
          target_level = 'NORMAL';
        } 
        if (level == "ALL") {
          _print('[' + target_level + '] ' + msg + '<b> ' + value + '</b>');
        } else if(level == "NORMAL") {
          if (target_level != "INFO" && target_level != "TRIVIAL")
            _print('[' + target_level + '] ' + msg + '<b> ' + value + '</b>');
        }
		  }
    }
  }
  if (typeof drikin.debug.assertEqual !== 'function') {
    drikin.debug.assertEqual = function(actual, expected) {
      if (isDebug) {      
        if (actual == expected) {
          print('ASSERT', 'Pass', actual);        
        } else {
          error('ASSERT', 'Error', actual);
        }
      }
    }
  }
  
  function print(level, msg, value) {
    if (isDebug) {
      _print('[' + level + '] <font color="blue">' + msg + '</font><b> ' + value + '</b>')
    }
  }
  function error(level, msg, value) {
    if (isDebug) {
      _print('[' + level + '] <font color="red">' + msg + '</font><b> ' + value + '</b>');
    }
  }
  function _print(txt) {
    if (body == '') {
      body = document.getElementsByTagName('body')[0];
    }
    if (document.getElementById(oid)) {
      out = document.getElementById(oid);
    } else {
      out = document.createElement('div');
      out.setAttribute('id', oid);
      body.appendChild(out);
    }
    var p = document.createElement('p');
    p.innerHTML = txt;
    out.appendChild(p);
    out.scrollTop = out.scrollHeight; // scroll to bottom
  }
}());

// create drikin.load
(function () {
  var loading = [];
  var loaded = ['dkapi'];     // remember loaded script into
  var head = '';              // caching header element
  var libs =  {'jquery': 'http://ajax.googleapis.com/ajax/libs/jquery/1.4.2/jquery.min.js',
               'jqueryui': 'http://ajax.googleapis.com/ajax/libs/jqueryui/1.8/jquery-ui.min.js',
               'jqueryfieldselection': 'http://drik.in/js/ext/jquery/jquery-fieldselection.pack.js',
               'jquerycaret': 'http://drik.in/js/ext/jquery/jquery.caret.min.js',
               'jqueryurl': '/js/ext/jquery/jquery.url/jquery.url.packed.js',
               'jqtouch': '/js/ext/jquery/jqtouch/jqtouch.js',
               'yui2': 'http://ajax.googleapis.com/ajax/libs/yui/2.8.0/build/yuiloader/yuiloader-min.js',
               'cssbeziers': '/js/ext/TouchScroll/src/css-beziers.js',
               'touchscroll': '/js/ext/TouchScroll/src/touchscroll.js',
               'touchscrolldummy': '/js/libs/touchscrolldummy.js',
               'swfobject': 'http://ajax.googleapis.com/ajax/libs/swfobject/2.2/swfobject.js',
               'kvsutil': '/js/libs/kvsutil.js',
               'class': '/js/libs/class.js'};
               
  var csses = {'debug': '/css/debug.css'};
     
  if (typeof drikin.load !== 'function') {
    drikin.load = function (name, callback) {
      for (var i = 0; i < loaded.length; i++) {
        if (name == loaded[i]) {
          if (typeof callback !== 'undefined')
            callback();
          return;
        }
      }
      if (name == 'debug') {
        if (drikin.isDebug()) {
          importCSS(name);
        }
      } else {
        loaded.push(name);
        loading.push({'name':name, 'callback':callback});
        if (loading.length == 1) {
          importJS();
        }
      }
    }
  }
  
  if (typeof drikin.loaded !== 'function') {
    drikin.loaded = function () {
      return loaded;
    }
  }
    
  function importJS() {
    if (loading.length > 0) {
      var load = loading[0];
      
      var name = load['name'];
      var callback = load['callback'];
      var url = libs[name];      
      if (!url)
        url = name;
      _writeScript(url, callback);
    }
  }
  
  function importCSS(name) {
    var url = csses[name];
    if (url) {
      _writeCSS(url);
    }
  }
    
  function _writeScript(src, callback) {
    if (head == '') {
      head = document.getElementsByTagName('head')[0];
    }
    var s = document.createElement('script');
    s.setAttribute('src', src);
    s.addEventListener("load", function() {
      if (typeof callback !== 'undefined')
        callback();
      if(loading.length > 0) {
        loading.shift();
        importJS();
      }
    }, false);
    head.appendChild(s);
  }
  
  function _writeCSS(txt) {
    if (head == '') {
      head = document.getElementsByTagName('head')[0];
    }
    var l = document.createElement('link');
    l.setAttribute('href', txt);
    l.setAttribute('media', 'screen');
    l.setAttribute('rel', 'stylesheet');
    l.setAttribute('type', 'text/css');
    head.appendChild(l);
  }
}());

// create drikin.setOnLoadCallback
(function () {
  var callback = '';
  
  if (typeof drikin.setOnLoadCallback !== 'function') {
    drikin.setOnLoadCallback = function(func) {
      callback = func;
      if(document.addEventListener){
        // document.addEventListener("DOMContentLoaded", _callback, false);
        document.addEventListener("DOMContentLoaded", _callback, false);
    	} else {
    	  window.onload = _callback;
    	}
    }
  }
  
  function _callback() {
    if (callback) {
      callback();
      callback = null;
    }
  }
}());