/* 
 * Spinbox plugin for jQuery
 * http://www.softwareunity.com/jquery/JQuerySpinBtn/
 *
 * Adds bells and whistles to any ordinary textbox to
 * make it look and feel like a SpinBox Control.
 *
 * Copyright (c) 2006-2010 Software Unity Ltd
 * Dual licensed under the MIT and GPL licenses:
 * http://www.softwareunity.com/jquery/MIT-LICENSE.txt
 * http://www.softwareunity.com/jquery/GPL-LICENSE.txt
 *
 * Originally written by George Adamson, Software Unity (george.jquery@softwareunity.com) August 2006.
 * Modifications made by Mark Gibson, (mgibson@designlinks.net) September 2006.
 * Rewritten and enhanced by George Adamson, Software Unity (george.jquery@softwareunity.com) October 2009.
 *
 * Tested in IE6, Opera9, Firefox 3.5.3
 * v1.0  11 Aug 2006 - George Adamson  - First release
 * v1.1     Aug 2006 - George Adamson  - Minor enhancements
 * v1.2  27 Sep 2006 - Mark Gibson    - Major enhancements
 * v1.3a 28 Sep 2006 - George Adamson  - Minor enhancements
 * v2.0   20 Oct 2009 - George Adamson  - Major refactor with breaking changes to options.
 
 Sample usage:
 
  // Create group of settings to initialise spinbutton(s). (Optional)
  var myOptions = {
    min: 0,              // Set lower limit or null for no limit.
    max: 100,            // Set upper limit or null for no limit.
    step: 0.5,            // Set increment size.
    spinboxClass: "mySpinBoxClass",  // CSS class to style the spinbutton. (Class also specifies url of the up/down button image.)
    upClass: "mySpinUpClass",    // CSS class for style when mouse over up button.
    downClass: "mySpinDnClass"    // CSS class for style when mouse over down button.
  }
 
  jQuery(document).ready(function($){

    // Initialise INPUT elements as SpinBoxes: (passing options if desired)
    $("INPUT.spinbox").spinbox(myOptions);

  });
 
 */

(function($){

$.fn.spinbox = function(options){

  // Tidy up when spinbox('destroy') is called:
  if( options && typeof(options)==="String" && options==="destroy" )
    return this.unbind(".spinbox")
      .removeClass(options.spinboxClass)
      .removeClass(options.upClass).removeClass(options.downClass)
      .removeClass(options.upHoverClass).removeClass(options.downHoverClass)
      .removeData("spinboxMin").removeData("spinboxMax").removeData("spinboxReset")
      .removeData("spinboxStep").removeData("spinboxBigStep")
  ;


  // Apply specified options or defaults:
  var undefined;    
  options = $.extend( {}, $.fn.spinbox.defaults, options );


  // Store min, max & reset values for each element: (Reset defaults to element's initial value if option undefined)
  this.each(function(){

    var $box  = $(this),
      min    = classData( "spinboxMin", this ),
      max    = classData( "spinboxMax", this ),
      step  = classData( "spinboxStep", this ),
      bigStep  = classData( "spinboxBigStep", this ),
      reset  = classData( "spinboxReset", this ),
      scale  = classData( "spinboxScale", this );  // AKA: Number of decimal places.

    if( min===undefined )  min    = firstNum( $box.attr("min"), options.min );
    if( max===undefined )  max    = firstNum( $box.attr("max"), options.max );
    if( !step )        step  = firstNum( $box.attr("step"), options.step );
    if( !bigStep )      bigStep  = firstNum( $box.attr("bigStep"), options.bigStep );
    if( reset===undefined )  reset  = firstNum( options.reset, $box.val(), min, max );
    if( scale===undefined )  scale  = $box.data("spinboxScale"); scale = ( scale || isNum(scale) ) ? scale : options.scale;

    // When scale option is true, auto derive the number of decimalPlaces to round to:
    if( scale === true ) scale = ( step.toString().split(".")[1] || "" ).length;

    $box.data( "spinboxMin", min );
    $box.data( "spinboxMax", max );
    $box.data( "spinboxStep", step );
    $box.data( "spinboxBigStep", bigStep );
    $box.data( "spinboxReset", reset );
    $box.data( "spinboxScale", scale );

  });


  return this.each(function(){

    // Flags used while mouse is being moved or pressed:
    var hoverUp, hoverDown, delayId, repeatId;
    var $box = $(this);

    // Bind event handlers for the spinbox:
    $box.bind("mousemove.spinbox",function(e){

      // Change css class when mouse is over an up/down button:
      var $box  = $(this);      
      var offset  = $box.offset();    // Calculate element left & top;
      var middle  = $box.height() / 2;  // Calculate midpoint between top and bottom of element;
      var hover  = ( e.pageX > offset.left + $box.width() - options.buttonWidth );
      hoverUp    = hover && ( e.pageY <= offset.top + middle );
      hoverDown  = hover && ( e.pageY >  offset.top + middle );

      $box.toggleClass( options.upHoverClass, hoverUp )
        .toggleClass( options.downHoverClass, hoverDown );
      // TODO: Stop autorepeat when mouse moves away from button?

    })

    .bind("mouseout.spinbox",function(){

      // Reset up/down buttons to their normal state when mouse moves away:
      stopAutorepeat();
      $(this).removeClass( [ options.upClass, options.downClass, options.upHoverClass, options.downHoverClass ].join(" ") );
      hoverUp = hoverDown = null;

    })

    .bind("mousedown.spinbox",function(e){

      // Update the spinbox value and set up autorepeat to start after a short delay:
      if( hoverUp || hoverDown ){

        $(this).toggleClass( options.upClass, hoverUp ).toggleClass( options.downClass, hoverDown );
        adjustValue.apply( this, [e] );
        startAutorepeat(this,e);

      };
    })

    .bind("mouseup.spinbox", function(e){
      stopAutorepeat();
      $(this).removeClass(options.upClass).removeClass(options.downClass);
    })

    //.bind("dblclick", function(e) {
    //  if ($.browser.msie)
    //    adjustValue.apply( this, [e, options.step, 1] );
    //})

    .bind("keydown.spinbox",function(e){

      // Filter key press by allowable options.keys if specified:
      if( !options.keys ||
        $.grep(options.keys, function(key){
          return key === e.keyCode || ( key instanceof RegExp && key.test( String.fromCharCode(e.keyCode) ) );
        }).length ){

        // Define arry key codes and decide whether to use options.bigStep when Shift is pressed:
        var $box  = $(this);
        var key    = { up:38, down:40, pageUp:33, pageDown:34 };
        var bigStep  = $box.data("spinboxBigStep");
        var step  = e.shiftKey ? bigStep : $box.data("spinboxStep");

        // Respond to up/down arrow keys and pageUp/pageDown:
        switch(e.keyCode){
          case key.up: adjustValue.apply( this, [e, step, 1] );  break;
          case key.down: adjustValue.apply( this, [e, step, -1] ); break;
          case key.pageUp: adjustValue.apply( this, [e, bigStep, 1] );  break;
          case key.pageDown: adjustValue.apply( this, [e, bigStep, -1] ); break;
        };
      }
      else
        // Cancel event if keys filter was specified but pressed key is not on the list:
        return !options.keys;
    })

    .bind("change.spinbox", function(e){
      adjustValue.apply( this, [e,0] );
    })

    .addClass(options.spinboxClass);



    // React to mousewheel if desired:
    if( options.mousewheel ){

      $(this).bind("mousewheel.spinbox DOMMouseScroll.spinbox", function(e){

        var step = e.shiftKey ? $(this).data("spinboxBigStep") : $(this).data("spinboxStep");

        // Respond to mouse wheel: (Allow for IE/Opera e.wheelDelta and W3C e.detail)
        if ( e.detail < 0 || e.wheelDelta >= 120 )
          adjustValue.apply( this, [e, step, 1] );
        else if ( e.detail > 0 || e.wheelDelta <= -120 )
          adjustValue.apply( this, [e, step, -1] );

        return false;
      });

    }


    // Initialise the current value, ensuring it is within min/max etc:
    adjustValue.apply( this, [$.Event(),0] );



    // Helper called in response to click or mousewheel etc to apply step change:
    function adjustValue(e,step,direction){

      var $box  = $(this); if( options.ignore && $box.is(options.ignore) ) return;
      step    = firstNum( step, $box.data("spinboxStep"), 1 );
      direction  = direction || (hoverDown ? -1 : 1);
      var oldVal  = $box.val();
      var val    = firstNum( oldVal, $box.data("spinboxReset"), 0 );
      var min    = firstNum( $box.data("spinboxMin") );
      var max    = firstNum( $box.data("spinboxMax") );
      var data  = [val,step,min,max,direction,oldVal,options];

      if( direction > 0 ) val = options.increment.apply( this,data ); else
      if( direction < 0 ) val = options.decrement.apply( this,data );
      if( isNum($box.data("spinboxScale")) && options.round ) val = options.round(val,$box.data("spinboxScale"));
      if( isNum(min) ) val = Math.max(val,min);
      if( isNum(max) ) val = Math.min(val,max);

      var data  = [val,step,min,max,direction,oldVal,options];
      if( val != oldVal && $box.triggerHandler("beforeSpin",data) !== false ){
        $box.val(val);
        if( options.change ) $box.trigger("change",data);
        $box.triggerHandler("spin",data);
      };
    };


    // Helper to begin autorepeat when mouse is held down:
    function startAutorepeat(elem,e){
      stopAutorepeat();
      // Start timer for initial delay:
      delayId = window.setTimeout(function(){
        adjustValue.apply( elem, [e] );
        // Start timer for repeating:
        repeatId = window.setInterval(function(){
          adjustValue.apply( elem, [e] );
        },options.repeat);
      },options.delay);
    };

    // Helper to end autorepeat when mouse is released:
    function stopAutorepeat(){
      window.clearTimeout(delayId);
      window.clearInterval(repeatId);
    };

  });

};



// Helper functions:

  // More reliable alternative to isNaN and isFinite:
  function isNum(num){
    return !isNaN(parseFloat(num))
  }

  // Helper to return the first parameter that is a valid number:
  function firstNum(args){
    for( var i=0; i<arguments.length; i++ ){
      if( isNum(arguments[i]) ) return Number( parseFloat(arguments[i]) );
    };
    return;
  };

  // Helper to extract settings stored in css class attribute string: (Eg: when class="spinbox spinboxStep0.5")
  function classData(attr,elem){

    var classes  = $(elem||this).attr("class"),
      match  = new RegExp( "(\\b" + attr + ")(\\S*)" ).exec(classes),
      lookupBoolean = { "true":true, "True":true, "false":false, "False":false };

    // Convert "True" or "False" string to boolean:
    if( match && match.length >= 3 && lookupBoolean[match[3]] !== undefined )
      match[3] = lookupBoolean[ match[3] ];

    return  !match ? undefined :      // attr not found in class string.
        match.length >= 3 ? match[2] :  // Specific value.
        null;              // attr specified but value deliberately blank.
  };





$.fn.spinbox.defaults = {
  min        : 0,            // Lower limit or null.
  max        : null,            // Upper limit or null.
  step      : 1,            // Size of standard increment.
  bigStep      : 10,            // Size of increment when Shift key is held down or when pageUp/pagedown is pressed.
  keys      : [ /[0-9]/,9,13,8,46,33,34,37,38,39,40,109,188,190 ],  // Array of regular expressions and/or char codes to restrict key input. Default: 0-9, Tab, Enter, Backspace, Delete, PageUp, PageDown, Left, Up, Right, Down, Minus, Comma, Dot.
  ignore      : "[readonly],[disabled]",  // Spinbox will not respond on elements matching this CSS selector.
  spinboxClass  : 'spinbox-active',      // Added to element when spinbox is initialised. Typically used to apply button image through css.
  upClass      : 'spinbox-up',        // Added to element while mouse is depressed on the Up button.
  downClass    : 'spinbox-down',      // Added to element while mouse is depressed on the Down button.
  upHoverClass  : 'spinbox-up-hover',    // Added to element while mouse is over the Up button.
  downHoverClass  : 'spinbox-down-hover',    // Added to element while mouse is over the Down button.
  mousewheel    : true,            // When true, spinbox will react to mousehweel.
  change      : true,            // When true, spinbox will trigger change event as it spins. (Otherwise change event is fired in the same ways as any normal textbox)
  increment    : function(val,step,min,max,options){ return val + step; },  // Custom function to calculate the value increment.
  decrement    : function(val,step,min,max,options){ return val - step; },  // Custom function to calculate the value decrement.
  reset      : null,            // Value used when element value is invalid. Specify null to default to element's initial value;
  delay      : 500,            // Initial delay before auto-repeat when mouse button held down. (Milliseconds)
  repeat      : 100,            // Interval between auto-repeats when mouse button held down. (Milliseconds)
  buttonWidth    : 20,            // Width of the button sprite image (so we can decide when mouse is over it).
  scale      : true,            // Specify number of DP, or true to auto derive from options.step (Eg: when step is 0.125 then DP will be 3)
  round      : function round(num,dp) {  // Specify your own decimalPlaces rounding function if you don't like this default one.
    return Math.round( num * Math.pow(10,dp) ) / Math.pow(10,dp);
  }
};

})(jQuery);