// JavaScript Document

/****************** FORM CHACK**********************/
function check(element){
	var Value=element.value;
	if(element.type=="text")
		if((isNaN(Value))||(Value<=0)) {
			element.style.background="#f99";
			return false;
			}
		else element.style.background="#cfc"; return true;
			
}


/****************** CALAC**********************/

function calctax(prePay){
	var f=document.forms[0];
		for(var i=0; i<f.elements.length; i++){
			if(!check(f.elements[i])) return false;
			
			if((f.elements[i].type=="radio")&&(f.elements[i].checked)){ var selector=f.elements[i].value;}
			if((f.elements[i].type=="text")&&(f.elements[i].name=="amount")){ var amount=f.elements[i].value;}
			if((f.elements[i].type=="text")&&(f.elements[i].name=="percent")){ var percent=f.elements[i].value;}
			if((f.elements[i].type=="text")&&(f.elements[i].name=="period")){ var period=f.elements[i].value;}
		}
		
		var outData=document.getElementById("output");
		var p=percent, n=period, S=amount;
		var msg="";
		Sum=new Array(0,0,0)
		yr=n/12;
		var imp=p*yr/(n*100);
		msg += "<table border=1 id=result align=center > <th>Ամիս</th><th>Գումար</th><th>Տոկոս</th><th>Ընդհանուր</th>";
		
			var k_val= new Array(0);
			var n_val=period;
			var a_val=amount;
			
		/****************** ANNUITY**********************/
		if(selector=="ann"){
				var K=imp*Math.pow((imp+1),n)/(Math.pow((imp+1),n)-1);
				var A=S*K;
					k_val[0]=S*prePay;
				for (var j=0;j<n;j++){
					k_val[j+1]=A;
					var Tok=imp*S;
					var Gum=A-Tok;
					msg += "<tr><td>"+(j+1)+"</td><td>"+Math.round(Gum)+"</td><td>"+Math.round(Tok)+"</td><td>"+Math.round(A)+"</td></tr>";
					Sum[0]+=Gum;
					Sum[1]+=Tok;
					Sum[2]+=A;
					S-=Gum;
				}
				msg+="<td></td><td><b>"+Math.round(Sum[0])+"</b></td><td><b>"+Math.round(Sum[1])+"</b></td><td><b>"+Math.round(Sum[2])+"</b></td>";
				msg+="</table>";

					msg+="<br/> Փաստացի տոկոսադրույքը -"+pastaci(n_val,a_val,k_val)+"%";
				outData.innerHTML= msg;
							
		}

		/****************** Decris**********************/
		if(selector=="dec"){
			var Gum1=S/n;
			k_val[0]=S*prePay;
			for (var j=0;j<n;j++){
			Tok=imp*S;
			k_val[j+1]=Gum1+Tok;
			Sum[0]+=Gum1;
			Sum[1]+=Tok;
			Sum[2]+=(Gum1+Tok);
			S-=Gum1;
			msg+= "<tr><td>"+(j+1)+"</td><td>"+Math.round(Gum1)+"</td><td>"+Math.round(Tok)+"</td><td>"+Math.round(Gum1+Tok)+"</td></tr>";
			}
			msg+="<td></td><td><b>"+Math.round(Sum[0])+"</b></td><td><b>"+Math.round(Sum[1])+"</b></td><td><b>"+Math.round(Sum[2])+"</b></td>";
			msg+="</table>";




			msg+="<br/> Փաստացի տոկոսադրույքը -"+pastaci(n_val,a_val,k_val);



			outData.innerHTML= msg;
		}
}


/****************** PASTACI**********************/

function pastaci(Nval,Aval,Kval){
	var Dval= new Array(0);
	var pt_index=1;
	var pt_Sum=0;
	for(var ik=0;ik<=Nval;ik++){Dval[ik]=ik*30;}
	
	while(Aval>=pt_Sum){
		pt_Sum=0;
		pt_index -=0.0001;
		for(var pt_i=0;pt_i<=Nval;pt_i++){
			pt_Sum+=(Kval[pt_i]/(Math.pow((1.0+pt_index),(Dval[pt_i] / 365))));
		}
	}
		var temp=Math.round(pt_index*10000);
		return temp/100;

}


/****************** RESET**********************/
function resetform(){
		var table=document.getElementById("result");
		var ch = table.parentNode;
		ch.removeChild(table);
}