function NeuronDrawer(contextName, width, height) {
    this._canvasWidth = width;
    this._canvasHeight = height;
    this._containerContextName = contextName;
    this._unknown_symbol=[1,4, 25,25, 75,25, 75,75, 25,75, 25,25];
    this._neuron_symbol=[1,4, 75,50, 25,0, 25,99, 75,50, 100,50];
    this._inputonly_symbol=[1,5, 25,40, 35,40, 45,50, 35,60, 25,60, 25,40];
    this._outputonly_symbol=[1,7, 75,50, 75,60, 55,60, 65,50, 55,40, 75,40, 75,50, 100,50];
    this._neurons = undefined;
    this._SCALE = 150;
    this._scale = 1;
    this._min_scale = 0.1;
    //Kinetic.js
    this._stage = undefined;
    this._layer = undefined;
}

NeuronDrawer.prototype.initializeNewCanvas = function () {

    this._stage = new Kinetic.Stage({
        container: this._containerContextName,
        width: this._canvasWidth,
        height: this._canvasHeight,
        draggable: true
    });

    this._layer = new Kinetic.Layer();

    this._addZoom();
}

NeuronDrawer.prototype._addZoom = function(){
    var self = this;

    var isFirefox = (/Firefox/i.test(navigator.userAgent)) ? true : false;

    var mousewheelevt= isFirefox ? "DOMMouseScroll" : "mousewheel" //FF doesn't recognize mousewheel as of FF3.x

    document.getElementById(this._containerContextName).addEventListener(mousewheelevt,function(e){
        e.preventDefault();

        var zoomAmount = 0;
        if(!isFirefox)
            zoomAmount = e.wheelDelta * 0.001;
        else
            zoomAmount = e.detail * -0.12;

        var newScale = self._stage.scale();
        newScale.x += zoomAmount;
        newScale.y += zoomAmount;

        self._stage.scale(newScale)
        self._stage.draw();
    });
}

NeuronDrawer.prototype.drawNeuralNetwork = function (neurons, connections, layouts, classes) {

    this._neurons = [];
    var offsetFactor = 0;

    for (var i = 0; i < layouts.length; i++) {
        var scheme = undefined;
        scheme = this._chooseSchema(i,neurons, connections, classes);

        var neuronData = this._getSize(scheme);
        neuronData.scheme = scheme;
        neuronData.x += layouts[i].x * this._SCALE;
        neuronData.y += -layouts[i].y * this._SCALE;

        this._neurons.push(neuronData);
        this.drawNeuron(layouts[i].x * this._SCALE, -layouts[i].y * this._SCALE, scheme);

        offsetFactor = Math.min(offsetFactor, layouts[i].x);
    }

    this._layer.offsetX(offsetFactor * this._SCALE);

    for (var i = 0; i < connections.length; i++)
        this.drawConnection(i, neurons, connections, einfos);
}

NeuronDrawer.prototype.drawNeuron = function (x, y, scheme) {
    var points = [];

    var position = 0;
    var noOfBlocks = scheme[position++];//number of "blocks" to draw
    var noOfLines = 0;//number of line to draw
    for (var i = 0; i < noOfBlocks; i++) {
        noOfLines = scheme[position++];

        for (var j = 0; j < noOfLines; j++) {
            points.push(scheme[position++]+x);
            points.push(scheme[position++]+y);
        }

        points.push(scheme[position++]+x);
        points.push(scheme[position++]+y);

        var symbol = new Kinetic.Line({
            points: points,
            stroke: 'black',
            strokeWidth: 1
        });

        symbol.move({x:0, y: 0});
        var self = this;
        symbol.on('mousemove', function(){
            var mousePos = self._stage.getPointerPosition();
            var x = mousePos.x;
            var y = mousePos.y;
            console.log(x,y);
        });

        this._layer.add(symbol);
        points = [];
    }
}

NeuronDrawer.prototype._getConnection = function(connections, id, number){

    var counter = 0;
    for(var i = 0; i < connections.length; i++)
    {
        if(connections[i].getDestination() == id)
            {
            if(counter == number)
                return connections[i].getSource();
            else
                counter++;
        }
    }
}

NeuronDrawer.prototype.drawConnection = function (id, neurons, connections, einfos) {

    var n2;
    neuroId = connections[id].getDestination();
    //this is hack trick to change order of inputs
    var maxVal = this._inputY(this._getNumberOfInputs(neuroId,connections), connections, neuroId);

    for(var input = 0; input < this._getNumberOfInputs(neuroId,connections); input++)
    {
        n2 = this._neurons[this._getConnection(connections, neuroId, input)];
        var points = [];

        var yw = this._inputY(input, connections, neuroId);
        var xw = (maxVal-yw) / 4;

        yw += this._neurons[neuroId].y;//add position of object to y

        points.push(this._neurons[neuroId].x);//x
        points.push(yw);//y

        points.push(this._neurons[neuroId].x - xw);//x
        points.push(yw);//y

        points.push(n2.x+n2.sizeX);
        points.push(n2.y + n2.sizeY/2);

        /*if(diagram?)
        {
            //straight forward
        }
        else
        {
            //U-shape
        }*/

        var line = new Kinetic.Line({
            points: points,
            stroke: 'black',
            strokeWidth: 1
        });
        this._layer.add(line);
    }

}

NeuronDrawer.prototype._inputY = function(number, connections, id){
    return ((1 + number)* this._neurons[id].sizeY) / ((this._getNumberOfInputs(id, connections)) + 1);
}

NeuronDrawer.prototype.finalize = function()
{
    this._stage.add(this._layer);
}

NeuronDrawer.prototype._getNumberOfInputs = function(number, connections){

    var counter = 0;

    for(var i = 0; i < connections.length; i++){
        if(connections[i].getDestination() == number)
            counter++;
    }

    return counter;
}

NeuronDrawer.prototype._getNumberOfOutputs = function(number, connections){
    var counter = 0;

    for(var i = 0; i < connections.length; i++){
        if(connections[i].getSource() == number)
            counter++;
    }

    return counter;
}



NeuronDrawer.prototype._chooseSchema = function(number, neurons, connections, classes)
{
    var schema = this._unknown_symbol;
    var type = neurons[number].getSchemeID();

    if(type != undefined)
    {
        if(classes[type].getScheme().length != 0)
        {
            if(this._getNumberOfInputs(number, connections) == 0)
                schema = this._outputonly_symbol;
            else if (this._getNumberOfOutputs(number, connections) == 0)
                schema = this._inputonly_symbol;
            else
                schema = this._neuron_symbol;
        }
    }

    return schema;
}

NeuronDrawer.prototype._getSize = function(scheme)
{
    var neuron = {sizeX: 0, sizeY: 0, x: 0, y: 0};


    var minX = Number.MAX_VALUE;
    var maxX = -1;

    var minY = Number.MAX_VALUE;
    var maxY = -1;

    var position = 0;
    var noOfBlocks = scheme[position++];//number of "blocks" to draw
    var noOfLines = 0;//number of line to draw

    for (var i = 0; i < noOfBlocks; i++) {
        noOfLines = scheme[position++];

        for (var j = 0; j < noOfLines; j++) {


            if(scheme[position] > maxX)
                maxX = scheme[position];
            if(scheme[position] < minX)
                minX = scheme[position];
            position++;

            if(scheme[position] > maxY)
                maxX = scheme[position];
            if(scheme[position] < minY)
                minY = scheme[position];
            position++;


            if(scheme[position] > maxX)
                maxX = scheme[position];
            if(scheme[position] < minX)
                minX = scheme[position];
            position++;

            if(scheme[position] > maxY)
                maxY = scheme[position];
            if(scheme[position] < minY)
                minY = scheme[position];
            position++;

            position = position - 2;
        }
        position = position + 2;//move to value which define number of lines to draw
        neuron.sizeX = maxX - minX;
        neuron.sizeY = maxY - minY;
        neuron.x = minX;
        neuron.y = minY;
    }
    return neuron;
}