/*********************************************************
Alexis C. Montenegro © March 2006                         
Use and/or modify this code freely. If you redistribute it
please include this and/or any other comment blocks and a 
description of any changes you make.                      
**********************************************************/

var fpArray = new Array();

function preMain(){
    setPriceStudy(false);
    setStudyTitle("Coppock Curve");
    setCursorLabelName("Coppock",0);
    setDefaultBarFgColor(Color.blue, 0);  
    var x=0;
    fpArray[x] = new FunctionParameter("Length1", FunctionParameter.NUMBER);
	with(fpArray[x++]){
        setLowerLimit(1);		
        setDefault(11);
    }
    fpArray[x] = new FunctionParameter("Length2", FunctionParameter.NUMBER);
	with(fpArray[x++]){
        setLowerLimit(1);		
        setDefault(14);
    }
    fpArray[x] = new FunctionParameter("Smooth", FunctionParameter.NUMBER);
	with(fpArray[x++]){
        setLowerLimit(1);		
        setDefault(10);
    }
    fpArray[x] = new FunctionParameter("Source", FunctionParameter.STRING);
	with(fpArray[x++]){
        addOption("open"); 
        addOption("high");
        addOption("low");
        addOption("close");
        addOption("hl2");
        addOption("hlc3");
        addOption("ohlc4"); 
        setDefault("close"); 
    }
    fpArray[x] = new FunctionParameter("Symbol", FunctionParameter.STRING);
    with(fpArray[x++]){
        setDefault();
	}
	fpArray[x] = new FunctionParameter("Interval", FunctionParameter.STRING);
	with(fpArray[x++]){
        setDefault();
    }
    fpArray[x] = new FunctionParameter("Params", FunctionParameter.BOOLEAN);
	with(fpArray[x++]){
        setName("Show Parameters");
        setDefault(false);
    }
}

var bInit = false;
var xCoppock = null;

function main(Length1,Length2,Smooth,Source,Symbol,Interval,Params){
    if(bInit==false){
        if(Symbol == null) Symbol = getSymbol();
        if(Interval == null) Interval = getInterval();
        var vSymbol = Symbol+","+Interval;
        xCoppock = getSeries(wma(Smooth,efsInternal("calc",Length1,Length2,eval(Source)(sym(vSymbol)))));
        addBand(0,PS_SOLID,1,Color.black,"0");
        setShowTitleParameters(eval(Params));
        bInit = true;
    }
    return xCoppock;
}

var xInit = false;
var xROC1 = null;
var xROC2 = null;

function calc(length1,length2,source){
    if(xInit==false){
        xROC1 = roc(length1,source);
        xROC2 = roc(length2,source);
        xInit = true;
    }
    var nROC1 = xROC1.getValue(0);
    var nROC2 = xROC2.getValue(0);
    if(nROC1==null || nROC2==null) return;
    return (nROC1+nROC2);
}