var Simulateur = Class.create({
	
	initialize: function()
	{
		this.fieldMontant 	= $('montant');
		this.fieldDuree		= $('duree');
		this.fieldTaux		= $('taux');
		this.fieldMontant.observe('keyup',this.checkMontant.bind(this));
		this.fieldDuree.observe('keyup',this.checkDuree.bind(this));
		this.fieldTaux.observe('keyup',this.checkTaux.bind(this));
		
	},
	
	checkMontant : function(){
		this.formatNumber(this.fieldMontant);
		this.calc();
	},
	
	checkDuree : function(){
		this.formatNumber(this.fieldDuree);
		this.calc();
	},
	
	checkTaux : function(){
		this.formatNumber(this.fieldTaux);
		this.calc();
	},
	
	formatNumber : function(field){
		field.value = field.value.replace(',','.');
		field.value = field.value.replace(' ','');
		if(isNaN(field.value)){
			field.value = field.value.substring(0, field.value.length-1);
			this.formatNumber(field);
		}
	},
	
	calc : function(){
		if(	!isNaN(this.fieldMontant.value) &&
			!isNaN(this.fieldDuree.value) && 
			!isNaN(this.fieldTaux.value) && 
			this.fieldDuree.value != 0 && 
			this.fieldTaux.value != 0 && 
			this.fieldMontant.value != 0)
		{
			/*var interets = this.fieldMontant.value*(this.fieldTaux.value/100);
			var totalDu  = parseInt(this.fieldMontant.value)+(interets);
			var res = totalDu/(12*this.fieldDuree.value);*/
			
			var puissance = Math.pow((1+(this.fieldTaux.value/1200)),(-12*this.fieldDuree.value));
			
			var res = (parseInt(this.fieldMontant.value)*(this.fieldTaux.value/1200))/(1-puissance);
			$('resultatSimulateur').update((Math.ceil(res*100))/100+'€');
			
		}
	}
});

Event.observe(window,'load',function()
{
	if($('simulateur'))
	{
		new Simulateur();
	}
});