var toArray = Array.from = function(iterable) {
  if (!iterable) return [];
  if (iterable.toArray) {
    return iterable.toArray();
  } else {
    var results = [];
    for (var i = 0; i < iterable.length; i++)
      results.push(iterable[i]);
    return results;
  }
}

Function.prototype.bind = function() {
  var theMethod = this, args = toArray(arguments), object = args.shift();
  return function() {
    return theMethod.apply(object, args.concat(toArray(arguments)));
  }
}
// Added on Jun-30-2007.

// Added on Jul-12-2007.
Function.prototype.bindAsEventListener = function(object) {
  var theMethod = this, args = toArray(arguments), object = args.shift();
  return function(event) {
    return theMethod.apply(object, [( event || window.event)].concat(args).concat(toArray(arguments)));
  }
}


if (!aaSuggest) {
  var aaSuggest = {};
}

function aaSuggest() {

  var inputField;
  var suggestArea;
  var candidateList;
  var suggestedList;
  var suggestedIndexList;
  var activePosition;
  var timer;
  var inputedValueBackup;
  var oldText;

  var interval;
  var displayMax;
  var listTag;
  var prefix;
  var ignoreCase;
  var dispAllKey;

  /**
   * Initialize
   */
  this.initSuggest = function(inputFieldEle, suggestAreaDivEle, candidateList) {
    //this.inputField = document.getElementById(inputFieldId);
    this.inputField =inputFieldEle;
    //this.suggestArea = document.getElementById(suggestAreaDivId);
    this.suggestArea = suggestAreaDivEle;
    this.candidateList = candidateList;
    this.timer = null;
    this.inputedValueBackup = "";
    this.oldText = null;
    this.interval = 500;
    this.displayMax = 10;
    this.listTag = 'div';
    //this.prefix = false;
    this.prefix = true;
    this.ignoreCase = true;
    this.dispAllKey = false;

    // Set the event handler.
    this.addListener(this.inputField, 'focus', this.suggestInputFocus.bind(this), false);
    this.addListener(this.inputField, 'blur', this.suggestInputBlur.bind(this), false);
    
    //IE系対応でkeydownイベント化
    //this.addListener(this.inputField, 'keypress', this.suggestInputKeypress.bind(this), false);
	this.addListener(this.inputField, 'keydown', this.suggestInputKeypress.bind(this), false);
    // Initialize the suggest area.
    this.clearSuggestArea();
  }

  /**
   * Handle the event for the input field when would be focused in.
   */
  this.suggestInputFocus = function() {
    var text = this.getInputText();
    if (text != this.oldText) {
      this.oldText = text;
      // Search the word.
      this.doSearch();
    }
    if (this.timer) clearTimeout(this.timer);
    // Confirm the input word after some interval.
    this.timer = setTimeout(this.suggestInputFocus.bind(this), this.interval);
  }

  /**
   * Handle the event for the input field when would be focused out.
   */
  this.suggestInputBlur = function(event) {
    this.unactive();
    this.oldText = this.getInputText();
    if (this.timer) clearTimeout(this.timer);
    this.timer = null;
    // clear the suggest area after 0.5ms.
    setTimeout((function(){ this.clearSuggestArea(); }).bind(this), 500);
  }

  /**
   * Handle the event for the input field when any key pressed.
   */
  this.suggestInputKeypress = function(event) {
    if (!this.timer) this.timer = setTimeout(this.suggestInputFocus.bind(this), this.interval);
    if (this.dispAllKey && event.ctrlKey && this.getInputText() == '' && !this.suggestedList && event.keyCode == '40') {
      this.stopEvent(event);
      this.displayAllSuggest();
    } else if (event.keyCode == '38' || event.keyCode == '40') { // UP or DOWN
      this.stopEvent(event);
      this.moveActiveList(event.keyCode);
    } else if (event.keyCode == '13') { // RETURN
      if (this.suggestedList) {
        this.stopEvent(event);
        this.clearSuggestArea();
      }
    } else if (event.keyCode == '27') { // ESCAPE
      if (this.suggestedList) {
        this.stopEvent(event);
        this.clearSuggestArea();
        this.inputField.value = this.inputedValueBackup;
        this.oldText = this.getInputText();
      }
    }
  }



  /**
   * Search the inputed word from the candidate list.
   */
  this.doSearch = function() {
    this.clearSuggestArea();
    var text = this.getInputText();
    if (text == '') return;
    var resultList = new Array();
    var temp = null; 
    this.suggestedIndexList = new Array();
    for (var i = 0; i < this.candidateList.length; i++) {
      if ((temp = this.isMatch(this.candidateList[i], text)) != null) {
        resultList.push(temp);
        this.suggestedIndexList.push(i);
        if (this.displayMax != 0 && resultList.length >= this.displayMax) break;
      }
    }
    if (resultList != 0) this.createSuggestArea(resultList);
  }

  /**
   * Match the word of the pattern.
   */
  this.isMatch = function(value, pattern) {
    var matchPos;
    if (this.ignoreCase) {
      pos = value.toLowerCase().indexOf(pattern.toLowerCase());
    } else {
      pos = value.indexOf(pattern);
    }
    if ((this.prefix && (pos != 0)) || (!this.prefix && (pos == -1))) return null;
    return value;
  }

  /**
   * Display the suggest area.
   */
  this.displayAllSuggest = function() {
    this.clearSuggestArea();
    this.oldText = this.getInputText();
    this.suggestedIndexList = new Array();
    for (var i = 0; i < this.candidateList.length; i++) {
      this.suggestIndexList.push(i);
    }
    this.createSuggestArea(this.candidateList);
  }

  /**
   * Create the suggest area contents.
   */
  this.createSuggestArea = function(resultList) {
    this.suggestedList = new Array();
    this.inputValueBackup = this.inputField.value;

    for (var i = 0; i < resultList.length; i++) {

      // Create and append the element and set the text.
      var elm = document.createElement(this.listTag);
      elm.innerHTML = resultList[i];
      this.suggestArea.appendChild(elm);

      // Set the event handler.
      this.addListener(elm, 'click', new Function('event', 'this.suggestedListClick(event, ' + i + ');').bind(this), false);
      this.addListener(elm, 'mouseover', new Function('event', 'this.suggestedListOver(event, ' + i + ');').bind(this), false);
      this.addListener(elm, 'mouseout', new Function('event', 'this.suggestedListOut(event, ' + i + ');').bind(this), false);

      this.suggestedList.push(elm);
    }
    this.suggestArea.style.display = 'block';
  }

  /**
   * Clear the suggest area.
   */
  this.clearSuggestArea = function() {
    this.suggestArea.innerHTML = '';
    this.suggestArea.style.display = 'none';
    this.suggestedList = null;
    this.suggestedIndexList = null;
    this.activePosition = null;
  }

  /**
   * Handle the event which move on the suggest area.
   */
  this.moveActiveList = function(keyCode) {
    if (!this.suggestedList || this.suggestedList.length == 0) return;
    this.unactive();
    //if (keyCode == Event.KEY_UP) {
    if (keyCode == '38') { // UP
      if (this.activePosition == null) {
        this.activePosition = this.suggestedList.length - 1;
      } else {
        this.activePosition--;
        if (this.activePosition < 0) {
          this.activePosition = null;
          this.inputField.value = this.inputValueBackup;
          return;
        }
      }
    } else { // DOWN
      if (this.activePosition == null) {
        this.activePosition = 0;
      } else {
        this.activePosition++;
      }
      if (this.activePosition >= this.suggestedList.length) {
        this.activePosition = null;
        this.inputField.value = this.inputValueBackup;
        return;
      }
    }
    this.active(this.activePosition);
  }

  /**
   * Handle the event for the suggest area when clicked.
   */
  this.suggestedListClick = function(event, index) {
    this.unactive();
    this.activePosition = index;
    this.active(index);
  }

  /**
   * Handle the event for the suggest area when mouse over.
   */
  this.suggestedListOver = function(event, index) {
    var elm = event.target || event.srcElement;
    this.moverDisplay(elm);
  }

  /**
   * Handle the event for the suggest area when mouse out.
   */
  this.suggestedListOut = function(event, index) {
    var elm = event.target || event.srcElement;
    if (!this.suggestedList) return;
    if (index == this.activePosition) {
      this.activeDisplay(elm);
    } else {
      this.unactiveDisplay(elm);
    }
  }

  /**
   * Get the text on the observed field.
   */
  this.getInputText = function() {
    return this.inputField.value;
  }

  /**
   * Set the text on the observed field.
   */
  this.setInputText = function(text) {
    this.inputField.value = text;
  }

  /**
   * Activate the suggenst area.
   */
  this.active = function(index) {
    this.activeDisplay(this.suggestedList[index]);
    this.setInputText(this.candidateList[this.suggestedIndexList[index]]);
    this.oldText = this.getInputText();
    this.inputField.focus();
  }

  /**
   * Unactivate the suggenst area.
   */
  this.unactive = function() {
    if (this.suggestedList != null && this.suggestedList.length > 0 && this.activePosition != null) {
      this.unactiveDisplay(this.suggestedList[this.activePosition]);
    }
  }

  /**
   * Activate the element, switch to the 'select' style.
   */
  this.activeDisplay = function(elm) {
    elm.className = 'select';
  }

  /**
   * Unactivate the element, drop to the style.
   */
  this.unactiveDisplay = function(elm) {
    elm.className = '';
  }

  /**
   * Mouse overed the element, switch to the 'over' style.
   */
  this.moverDisplay = function(elm) {
    elm.className = 'over';
  }

  /**
   * Add the listener function on the element.
   */
  this.addListener = function(elm, eventType, func, cap) {
    if (elm.addEventListener) {
      elm.addEventListener(eventType, func, cap);
    } else if (elm.attachEvent) {
      elm.attachEvent('on' + eventType, func);
    }
  }

  /**
   * Stop the event handling.
   */
  this.stopEvent = function(event) {
    if (event.preventDefault) {
      event.preventDefault();
      event.stopPropagation();
    } else {
      event.returnValue = false;
      event.cancelBubble = true;
    }
  }

}