/**
 * Classe para mascara dinamica de formularios
 * 
 * @author Abdala Cerqueira <abdala.cerqueira@gmail.com>
 * @author Jose Roberto de Oliveira <bertono@gmail.com>
 * 
 */
var Mask = function()
{
	var strMask;
	var target;	
	var randomId;	
	var maxLength;
	var e;
	  
	var is_ie = ( /msie/i.test(navigator.userAgent) && !/opera/i.test(navigator.userAgent) );
	
	/**
  	 * Recupera o evento independente do browser
  	 * 
  	 * @param event e
  	 */
  	this.getEvent = function( e ) 
  	{
		e = is_ie ? window.event : e;
		(e = e || event).preventDefault || (e.preventDefault = function(){e.returnValue = false;});
		e.stopPropagation || (e.stopPropagation = function(){e.cancelBubble = true;});
		e.target || (e.target = e.srcElement || null);
		e.key = (e.which + 1 || e.keyCode + 1) - 1 || 0;
		return e;
	}
	
	/**
	 * Setar os atributos mascara e campo que esta sendo aplicada a mascara
	 * Adiciona a função apply no evento de keypress
	 * 
	 * @param mixed mixTargetId Id do campo que vai receber a mascara
	 * @param object objMask objeto que será usado para aplicar a mascara
	 * @param string strMaskSet mascara
	 * @param mixed mixId ID de outro campo que queira ter interacao
	 * 
	 */
	this.init = function( mixTargetId , objMask , strMaskSet , mixId )
	{
		strMask = strMaskSet;
		target = document.getElementById( mixTargetId );	
		randomId = mixId;
		if( randomId ) maxLength = document.getElementById( randomId ).value;
		  
		if( strMaskSet == "DC" )
		{
			target["onkeyup"] = function( event ) 
			{
				objMask.reduce();
			};
		}	
		else
		{
			target["onkeypress"] = function( event ) 
			{
				e = objMask.getEvent( event );
				
				if( strMaskSet == "INT" )
				{
					objMask.integer();
				}
				else if( strMaskSet == "DS" )
				{
					objMask.description();
				}
				else if( strMaskSet == "MONEY" )
				{
					objMask.money();
				}
				else
				{
					objMask.apply();
				}
			};
		}
	}
  
  	/**
  	 * Aplica a mascara setada no initialize
  	 */
	this.apply = function()
	{
		var i;
		  	
		var strValue = target.value;
			
		target.maxLength = strMask.length;
			
		if( e.key == 8 || e.key == 9  ) return;
			
		if( !( ( e.key> 47 && e.key <58) || e.key == 8 || e.key == 127 || e.key == 0 || e.key == 9 || e.key == 13 ) )
		{
			e.key > 30 && e.preventDefault();
			return false;
		}
			
		if( strValue.length == 0 )
		{
			if ( strMask.charAt( 0 ) != 0 ) 
			{
				strValue +=  strMask.charAt( 0 ) + strValue;
			}
		}
			
		for ( i = 0 ; i < strValue.length ; i++ ) 
		{
			if ( strMask.charAt( i + 1 ) != 0 ) 
			{
				if ( ( strValue.length - 1 ) == i ) 
				{
					target.value +=  strMask.charAt( i + 1 );
				}
			}
		}
	}
	
	/**
  	 * Aplica marcara de somente numeros
  	 */
	this.integer = function()
	{
		if( !( ( e.key > 47 && e.key < 58 ) || e.key == 8 || e.key == 127 || e.key == 0 || e.key == 9 || e.key == 13 ) )
		{
			e.key > 30 && e.preventDefault();
		}
	}
	
	/**
  	 * Reduz o numero que esta no decrementador do textarea
  	 */
	this.reduce = function()
	{
		var reduzido = parseInt( maxLength ) - target.value.length;
		
		if( reduzido > -1 )
		{
			document.getElementById( randomId ).value = reduzido;
		}
		else
		{
			target.value = target.value.substring( 0, maxLength ); 
		}
		return;
	}
	
	/**
  	 * Aplica a mascara a um nome
  	 */
	this.description = function()
	{
		//Permiti espaço, enter e backspace
		if( ( e.key == 8 ) || ( e.key == 32 ) || ( e.key == 13 ) ) return;
		
		//Permiti os acentos
		if( e.key > 193 && e.key < 251 ) return;
		
		//Permiti todas as letras e bloqueia alguns caracteres
	    if( ( e.key > 64 && e.key < 123 ) && !( e.key > 90 && e.key < 97 ) )
	    {;}
	    else
	    {
	    	e.key > 30 && e.preventDefault();
	    }
	    return;
	}
	
	/**
  	 * Aplica a mascara de dinheiro 
  	 */
	this.money = function()
	{
		var o = target;
		 if ( !o.readonly )
		 {
		    if( e.key > 47 && e.key < 58 )
		    {
		    	var n = 2;
		        var s = ( target.value.replace( /^0+/g , "" ) + String.fromCharCode( e.key ) ).replace( /\D/g , "" );
		        var l = s.length;
		        
		        if( o.maxLength + 1 && l >= o.maxLength ) return false;
		        if( o.maxLength == o.value.length ) return false;
		        
		        l <= (n = 2) && (s = new Array(n - l + 2).join("0") + s);
		        for( var i = (l = ( s = s.split("") ).length ) - n; (i -= 3) > 0; s[i - 1] += "." );
		        n && n < l && ( s[l - ++n] += "," );
		        o.value = s.join( "" );
		    }
		    e.key > 30 && e.preventDefault();
		}
	}
}