//------------------------------------------------------------------------------

function drawLine(x1, y1, x2, y2, context, strokeStyle, lineWidth)
{
    context.beginPath();

    x1 = Math.floor(x1) + 0.5;
    x2 = Math.floor(x2) + 0.5;
    y1 = Math.floor(y1) + 0.5;
    y2 = Math.floor(y2) + 0.5;
    context.moveTo(x1, y1);
    context.lineTo(x2, y2);
    context.strokeStyle = strokeStyle;
    context.lineWidth = lineWidth;
    context.stroke();
}

//------------------------------------------------------------------------------

function drawHorizontalDashedLine(xx0, xx, yy0, dashLength, context, strokeStyle, lineWidth)
{
    n = 0;
    if (xx0 > xx) {
        tmp = xx0;
        xx0 = xx;
        xx = tmp;
    }
    while (true)
    {
        x1 = xx0 + dashLength * n;
        if (x1 > xx)
            break;
        x2 = xx0 + dashLength * (n + 1);
        if (x2 > xx)
            x2 = xx;
        drawLine(x1, yy0, x2, yy0, context, strokeStyle, lineWidth);
        n += 2;
    }
}

//---------------------------------------------------------------------------

function round(value, decimals)
{
    return Number(Math.round(value + 'e' + decimals) + 'e-' + decimals);
}

//------------------------------------------------------------------------------
function Levels(canvasName)
{ 
    var canvas = document.getElementById(canvasName);
    var context = canvas.getContext('2d');
    var canvasHeight = canvas.height;
    var canvasWidth = canvas.width;
	
    var lineWidth=1;
    this.getLineWidth = function () {
        return lineWidth;
    };
    this.setLineWidth = function (newVal) {
        lineWidth = newVal;
    };
   
    var data;
    this.setData = function (newVal)
    {
        data=newVal;
		this.draw(0, 0, 0, 0);//if(mode===0)//isFirstRun
    };
	this.getData = function () {
        return data;
    };
	
    var bgColor = "lightgoldenrodyellow";
    this.getBgColor = function () {
        return bgColor;
    };
    this.setBgColor = function (newVal) {
        bgColor = newVal;
    };
	
	var lineColor="red";
    this.getLineColor = function () {
        return lineColor;
    };
    this.setLineColor = function (newVal) {
        lineColor = newVal;
    };
	
	var fontColor="black";
	this.getFontColor = function () {
        return fontColor;
    };
    this.setFontColor = function (newVal) {
        fontColor = newVal;
    };	

	var font="12px Calibri";
	this.getFont = function () {
        return font;
    };
    this.setFont = function (newVal) {
        font = newVal;
    };	
	
	var isFirstRun = true;
	var isRestorePreviousScale=false;
	var zoomX1;
    var zoomY1;
	var canvas0;
    var canvas3;
    var context0;
	
    this.startZoom = function (x1, y1) {
		
        zoomX1 = x1;
        zoomY1 = y1;

        canvas0 = document.createElement('canvas');
        canvas0.width = canvas.width;
        canvas0.height = canvas.height;
        context0 = canvas0.getContext('2d');
        context0.drawImage(canvas, 0, 0);
    };	
	
    var canvas2 = document.createElement('canvas');
    canvas2.width = canvas.width;
    canvas2.height = canvas.height;
    var context2 = canvas2.getContext('2d');

    var canvas3 = document.createElement('canvas');
    canvas3.width = canvas.width;
    canvas3.height = canvas.height;
    var context3 = canvas3.getContext('2d');

    this.continueZoom = function (x2, y2) {

        context2.clearRect(0, 0, canvas.width, canvas.height);
        context3.clearRect(0, 0, canvas.width, canvas.height);

        context3.beginPath();
        //context3.rect(zoomX1, zoomY1, -(zoomX1 - x2), -(zoomY1 - y2));
		context3.lineWidth = 2;
        context3.strokeStyle = 'black';
        context3.stroke();
		drawLine(110-5, zoomY1, 110-5,  y2, context3, 'black', 2);
		drawLine(110+60+5, zoomY1, 110+60+5,  y2, context3, 'black', 2);

        context2.drawImage(canvas0, 0, 0);
        context2.drawImage(canvas3, 0, 0);
        context.drawImage(canvas2, 0, 0);
    };

    this.endZoom = function (x1, y1) {

        if (Math.abs(zoomX1 - x1) < 10 && Math.abs(zoomY1 - y1) < 10)
        {
            context.drawImage(canvas0, 0, 0);
            return;
        }
        this.draw(zoomY1, y1, 0, 2);//if(mode===2)//isZoom
    };
    
    this.restoreInitialScale = function () {
		
		this.draw(0, 0, 0, 3);//if(mode===3)//isDraw10=isRestoreInitialScale	
    };

    this.restorePreviousScale = function () {

        this.draw(0, 0, 0, 1);//if(mode===1)//isRestorePreviousScale
    };
	
	this.drawFirst10 = function ()
	{
		this.draw(0, 0, 0, 3);//if(mode===3)//isDraw10
	}
	
	this.drawAll = function ()
	{
		this.draw(0, 0, 0, 4);//if(mode===4)//isDrawAll
	}

	var C,COld,Dmin,Dmax,DminOld,DmaxOld;
    this.draw = function (y_start, y_end, numLev, mode)
    {
	    var data1=[],data2=[],data3=[];
        var tmp1= data.split('\n');
        var i;
        
        for(i=0;i<tmp1.length;i++) 
        {    
            data1[i]=tmp1[i].split('\t')[0]; data1[i]*=1.0; //highly important
            data2[i]=tmp1[i].split('\t')[1];
            data3[i]=tmp1[i].split('\t')[2];            
        }
              
        context.beginPath();
        context.fillStyle = bgColor;
        context.fillRect(1, 1, canvasWidth - 2, canvasHeight - 2);
        
        context.beginPath();
		context.lineWidth = lineWidth;
        context.rect(0.5, 0.5, canvasWidth - 1, canvasHeight - 1);
		context.strokeStyle="black";
        context.stroke();

        var top = 20, left = 110, bottom = 80, right = 20, lineLength=60;
        var margin=20;

		var iMin,iMax;
		
		if(mode===0)//isFirstRun
		{
			iMin=0; 
			iMax=Math.min(10,tmp1.length-1);

			Dmax=data1[iMax-1];
			Dmin=data1[iMin];
			C=(canvasHeight-2.*margin)/(data1[iMax-1]-data1[iMin]);
			
			DmaxOld=Dmax;
			DminOld=Dmin;			
			COld=C;			

			//alert("isFirstRun Dmin=" + Dmin + ", Dmax=" + Dmax);					
			//alert("isFirstRun DminOld=" + DminOld + ", DmaxOld=" + DmaxOld);													
		}
		if(mode===1)//isRestorePreviousScale
		{
			Dmax=DmaxOld;
			Dmin=DminOld;
			C=COld;
			
			DmaxOld=Dmax;
			DminOld=Dmin;			
			COld=C;
			
			//alert("isRestorePreviousScale Dmin=" + Dmin + ", Dmax=" + Dmax);					
			//alert("isRestorePreviousScale DminOld=" + DminOld + ", DmaxOld=" + DmaxOld);								
		}
		if(mode===2)//isZoom
		{			
			DmaxOld=Dmax;
			DminOld=Dmin;
            COld=C;
			
			if(y_start>canvasHeight-margin) y_start=canvasHeight-margin;
			if(y_start<margin) y_start=margin;
			if(y_end>canvasHeight-margin) y_end=canvasHeight-margin;
			if(y_end<margin) y_end=margin;			

			Dmax=Dmin+(canvasHeight-margin-y_start)/C;
			Dmin=Dmin+(canvasHeight-margin-y_end)/C;

			if( Dmin > Dmax ) [Dmin, Dmax]=[Dmax, Dmin];
			if( Dmin < 0. ) Dmin=0.; 
			C=(canvasHeight-2.*margin)/(Dmax-Dmin);		
			
			//alert("isZoom Dmin=" + Dmin + ", Dmax=" + Dmax);					
			//alert("isZoom DminOld=" + DminOld + ", DmaxOld=" + DmaxOld);					
		}
		if(mode===3)//isDraw10
		{
			DmaxOld=Dmax;
			DminOld=Dmin;
            COld=C;

			iMin=0; 
			iMax=Math.min(10,tmp1.length-1);

			Dmax=data1[iMax-1];
			Dmin=data1[iMin];
			C=(canvasHeight-2.*margin)/(data1[iMax-1]-data1[iMin]);
			
			//alert("isDraw10 Dmin=" + Dmin + ", Dmax=" + Dmax);					
			//alert("isDraw10 DminOld=" + DminOld + ", DmaxOld=" + DmaxOld);					
		}
		if(mode===4)//isDrawAll
		{
			DmaxOld=Dmax;
			DminOld=Dmin;
            COld=C;
			
			iMin=0; 
			iMax=tmp1.length-1;

			Dmax=data1[iMax-1];
			Dmin=data1[iMin];
			C=(canvasHeight-2.*margin)/(data1[iMax-1]-data1[iMin]);	
			
			//alert("isDrawAll Dmin=" + Dmin + ", Dmax=" + Dmax);					
			//alert("isDrawAll DminOld=" + DminOld + ", DmaxOld=" + DmaxOld);			
		}
		
	    //for(i=iMin;i<iMax;i++) 
		for(i=0;i<tmp1.length-1;i++) 
        {
            if(data1[i]>=Dmin-1.e-10 && data1[i]<=Dmax+1.e-10)
			{			
				x1 = left;
				if(Dmin===Dmax)
				{
					if(tmp1.length-1>1) yy=canvasHeight-margin-i*(canvasHeight-2.*margin)/(tmp1.length-2);
					else yy=canvasHeight-margin;
				}				
				else yy=canvasHeight-margin-(data1[i]-Dmin)*C;			
				y1 = yy;
				x2 = left+lineLength;
				y2 = yy;
				
				if(i!=0 && data1[i]<1.e-10) drawHorizontalDashedLine(x1, x2, y1, 6, context, lineColor, lineWidth);
				else drawLine(x1, y1, x2, y2, context, lineColor, lineWidth);

				context.textAlign = "left";
				context.textBaseline = "bottom";
				context.font = font;
				context.fillStyle = fontColor;

				context.fillText(round(data1[i],1)+ " keV", 10, yy+10);
				if(data3[i]) context.fillText(data3[i], 70, yy+10);
				if(data2[i]) context.fillText(data2[i], 190, yy+10);    
			
				if(i===0)
				{
					for (j = 0; j < lineLength/5; j++)
					{
						var x1,y1,x2,y2;
						x1 = left+(j+0)*5;;
						y1 = canvasHeight-margin+5;
						x2 = left+(j+1)*5;
						y2 = canvasHeight-margin;
						drawLine(x1, y1, x2, y2, context, lineColor, lineWidth);
					}
				}
			}			
		} 
    }	
	
	this.readData=function(z,a,func) {
		$.get("../common/get_levels.php",{ z: z,a: a})
			.done(function(data){ 
				eval(func+".setData('"+data.replace(new RegExp("\n","g"),"\\n")+"')");
			});
	}
}
//------------------------------------------------------------------------------