nv.models.OTRSlineChart = function() {
    "use strict";

    //============================================================
    // Public Variables with Default Settings
    //------------------------------------------------------------

    var lines = nv.models.line()
        , xAxis = nv.models.axis()
        , yAxis = nv.models.axis()
        , legend = nv.models.legend()
        , interactiveLayer = nv.interactiveGuideline()
        ;

    var margin = {top: 30, right: 20, bottom: 50, left: 60}
        , color = nv.utils.defaultColor()
        , width = null
        , height = null
        , showLegend = true
        , showXAxis = true
        , showYAxis = true
        , rightAlignYAxis = false
// ---
// OTRS
// ---
        , reduceXTicks = true
        , staggerLabels = false
// ---
        , useInteractiveGuideline = false
        , tooltips = true
        , tooltip = function(key, x, y, e, graph) {
            return '<h3>' + key + '</h3>' +
// ---
// OTRS
// ---
//                '<p>' +  y + ' at ' + x + '</p>'
                '<p>' +  y + ' - ' + x + '</p>'
// ---
        }
        , x
        , y
        , state = nv.utils.state()
        , defaultState = null
// ---
// OTRS
// ---
//        , noData = 'No Data Available.'
        , noData = Core.Language.Translate('No Data Available.')
// ---
        , dispatch = d3.dispatch('tooltipShow', 'tooltipHide', 'stateChange', 'changeState', 'renderEnd')
        , duration = 250
        ;

// ---
// OTRS
// ---
//    xAxis.orient('bottom').tickPadding(7);
    xAxis.orient('bottom').tickPadding(7).showMaxMin(false);
// ---

    yAxis
        .orient((rightAlignYAxis) ? 'right' : 'left')
    ;

    //============================================================
    // Private Variables
    //------------------------------------------------------------

    var showTooltip = function(e, offsetElement) {
        var left = e.pos[0] + ( offsetElement.offsetLeft || 0 ),
            top = e.pos[1] + ( offsetElement.offsetTop || 0),
            x = xAxis.tickFormat()(lines.x()(e.point, e.pointIndex)),
            y = yAxis.tickFormat()(lines.y()(e.point, e.pointIndex)),
            content = tooltip(e.series.key, x, y, e, chart);

        nv.tooltip.show([left, top], content, null, null, offsetElement);
    };

    var renderWatch = nv.utils.renderWatch(dispatch, duration);

    var stateGetter = function(data) {
        return function(){
            return {
                active: data.map(function(d) { return !d.disabled })
            };
        }
    };

    var stateSetter = function(data) {
        return function(state) {
            if (state.active !== undefined)
                data.forEach(function(series,i) {
                    series.disabled = !state.active[i];
                });
        }
    };

    function chart(selection) {
        renderWatch.reset();
        renderWatch.models(lines);
        if (showXAxis) renderWatch.models(xAxis);
        if (showYAxis) renderWatch.models(yAxis);

        selection.each(function(data) {
            var container = d3.select(this),
                that = this;
            nv.utils.initSVG(container);
            var availableWidth = (width  || parseInt(container.style('width')) || 960)
                    - margin.left - margin.right,
                availableHeight = (height || parseInt(container.style('height')) || 400)
                    - margin.top - margin.bottom;


            chart.update = function() {
                if (duration === 0)
                    container.call(chart);
                else
                    container.transition().duration(duration).call(chart)
            };
            chart.container = this;

            state
                .setter(stateSetter(data), chart.update)
                .getter(stateGetter(data))
                .update();

            // DEPRECATED set state.disableddisabled
            state.disabled = data.map(function(d) { return !!d.disabled });

            if (!defaultState) {
                var key;
                defaultState = {};
                for (key in state) {
                    if (state[key] instanceof Array)
                        defaultState[key] = state[key].slice(0);
                    else
                        defaultState[key] = state[key];
                }
            }

            // Display noData message if there's nothing to show.
            if (!data || !data.length || !data.filter(function(d) { return d.values.length }).length) {
                var noDataText = container.selectAll('.nv-noData').data([noData]);

                noDataText.enter().append('text')
                    .attr('class', 'nvd3 nv-noData')
                    .attr('dy', '-.7em')
                    .style('text-anchor', 'middle');

                noDataText
                    .attr('x', margin.left + availableWidth / 2)
                    .attr('y', margin.top + availableHeight / 2)
                    .text(function(d) { return d });

                return chart;
            } else {
                container.selectAll('.nv-noData').remove();
            }


            // Setup Scales
            x = lines.xScale();
            y = lines.yScale();

            // Setup containers and skeleton of chart
            var wrap = container.selectAll('g.nv-wrap.nv-lineChart').data([data]);
            var gEnter = wrap.enter().append('g').attr('class', 'nvd3 nv-wrap nv-lineChart').append('g');
            var g = wrap.select('g');

            gEnter.append("rect").style("opacity",0);
            gEnter.append('g').attr('class', 'nv-x nv-axis');
            gEnter.append('g').attr('class', 'nv-y nv-axis');
            gEnter.append('g').attr('class', 'nv-linesWrap');
            gEnter.append('g').attr('class', 'nv-legendWrap');
            gEnter.append('g').attr('class', 'nv-interactive');

            g.select("rect")
                .attr("width",availableWidth)
                .attr("height",(availableHeight > 0) ? availableHeight : 0);

            // Legend
            if (showLegend) {
                legend.width(availableWidth);

                g.select('.nv-legendWrap')
                    .datum(data)
                    .call(legend);

                if ( margin.top != legend.height()) {
                    margin.top = legend.height();
                    availableHeight = (height || parseInt(container.style('height')) || 400)
                        - margin.top - margin.bottom;
                }

                wrap.select('.nv-legendWrap')
                    .attr('transform', 'translate(0,' + (-margin.top) +')')
            }

            wrap.attr('transform', 'translate(' + margin.left + ',' + margin.top + ')');

            if (rightAlignYAxis) {
                g.select(".nv-y.nv-axis")
                    .attr("transform", "translate(" + availableWidth + ",0)");
            }

            //Set up interactive layer
            if (useInteractiveGuideline) {
                interactiveLayer
                    .width(availableWidth)
                    .height(availableHeight)
                    .margin({left:margin.left, top:margin.top})
                    .svgContainer(container)
                    .xScale(x);
                wrap.select(".nv-interactive").call(interactiveLayer);
            }

            lines
                .width(availableWidth)
                .height(availableHeight)
                .color(data.map(function(d,i) {
                    return d.color || color(d, i);
                }).filter(function(d,i) { return !data[i].disabled }));


            var linesWrap = g.select('.nv-linesWrap')
                .datum(data.filter(function(d) { return !d.disabled }));

            linesWrap.call(lines);

            // Setup Axes
            if (showXAxis) {
                xAxis
                    .scale(x)
                    .ticks( nv.utils.calcTicksX(availableWidth/100, data) )
                    .tickSize(-availableHeight, 0);

                g.select('.nv-x.nv-axis')
                    .attr('transform', 'translate(0,' + y.range()[0] + ')');
                g.select('.nv-x.nv-axis')
                    .call(xAxis);

// ---
// OTRS
// ---
                var xTicks = g.select('.nv-x.nv-axis > g').selectAll('g');

                xTicks
                    .selectAll('line, text')
                    .style('opacity', 1)
                if (staggerLabels) {
                    var getTranslate = function(x,y) {
                        return "translate(" + x + "," + y + ")";
                    };

                    var staggerUp = 5, staggerDown = 17;  //pixels to stagger by
                    // Issue #140
                    xTicks
                        .selectAll("text")
                        .attr('transform', function(d,i,j) {
                            return  getTranslate(0, (j % 2 == 0 ? staggerUp : staggerDown));
                        });

                    var totalInBetweenTicks = d3.selectAll(".nv-x.nv-axis .nv-wrap g g text")[0].length;
                    g.selectAll(".nv-x.nv-axis .nv-axisMaxMin text")
                        .attr("transform", function(d,i) {
                            return getTranslate(0, (i === 0 || totalInBetweenTicks % 2 !== 0) ? staggerDown : staggerUp);
                        });
                }

                if (reduceXTicks)
                    xTicks
                        .filter(function(d,i) {
                            return i % Math.ceil(data[0].values.length / (availableWidth / 100)) !== 0;
                        })
                        .selectAll('text, line')
                        .style('opacity', 0);
// ---

            }

            if (showYAxis) {
                yAxis
                    .scale(y)
                    .ticks( nv.utils.calcTicksY(availableHeight/36, data) )
                    .tickSize( -availableWidth, 0);

                g.select('.nv-y.nv-axis')
                    .call(yAxis);
            }

            //============================================================
            // Event Handling/Dispatching (in chart's scope)
            //------------------------------------------------------------

            legend.dispatch.on('stateChange', function(newState) {
                for (var key in newState)
                    state[key] = newState[key];
                dispatch.stateChange(state);
                chart.update();
            });

            interactiveLayer.dispatch.on('elementMousemove', function(e) {
                lines.clearHighlights();
                var singlePoint, pointIndex, pointXLocation, allData = [];
                data
                    .filter(function(series, i) {
                        series.seriesIndex = i;
                        return !series.disabled;
                    })
                    .forEach(function(series,i) {
                        pointIndex = nv.interactiveBisect(series.values, e.pointXValue, chart.x());
                        lines.highlightPoint(i, pointIndex, true);
                        var point = series.values[pointIndex];
                        if (typeof point === 'undefined') return;
                        if (typeof singlePoint === 'undefined') singlePoint = point;
                        if (typeof pointXLocation === 'undefined') pointXLocation = chart.xScale()(chart.x()(point,pointIndex));
                        allData.push({
                            key: series.key,
                            value: chart.y()(point, pointIndex),
                            color: color(series,series.seriesIndex)
                        });
                    });
                //Highlight the tooltip entry based on which point the mouse is closest to.
                if (allData.length > 2) {
                    var yValue = chart.yScale().invert(e.mouseY);
                    var domainExtent = Math.abs(chart.yScale().domain()[0] - chart.yScale().domain()[1]);
                    var threshold = 0.03 * domainExtent;
                    var indexToHighlight = nv.nearestValueIndex(allData.map(function(d){return d.value}),yValue,threshold);
                    if (indexToHighlight !== null)
                        allData[indexToHighlight].highlight = true;
                }

                var xValue = xAxis.tickFormat()(chart.x()(singlePoint,pointIndex));
                interactiveLayer.tooltip
                    .position({left: pointXLocation + margin.left, top: e.mouseY + margin.top})
                    .chartContainer(that.parentNode)
                    .enabled(tooltips)
                    .valueFormatter(function(d,i) {
                        return yAxis.tickFormat()(d);
                    })
                    .data(
                    {
                        value: xValue,
                        series: allData
                    }
                )();

                interactiveLayer.renderGuideLine(pointXLocation);

            });

            interactiveLayer.dispatch.on('elementClick', function(e) {
                var pointXLocation, allData = [];

                data.filter(function(series, i) {
                    series.seriesIndex = i;
                    return !series.disabled;
                }).forEach(function(series) {
                    var pointIndex = nv.interactiveBisect(series.values, e.pointXValue, chart.x());
                    var point = series.values[pointIndex];
                    if (typeof point === 'undefined') return;
                    if (typeof pointXLocation === 'undefined') pointXLocation = chart.xScale()(chart.x()(point,pointIndex));
                    var yPos = chart.yScale()(chart.y()(point,pointIndex));
                    allData.push({
                        point: point,
                        pointIndex: pointIndex,
                        pos: [pointXLocation, yPos],
                        seriesIndex: series.seriesIndex,
                        series: series
                    });
                });

                lines.dispatch.elementClick(allData);
            });

            interactiveLayer.dispatch.on("elementMouseout",function(e) {
                dispatch.tooltipHide();
                lines.clearHighlights();
            });

            dispatch.on('tooltipShow', function(e) {
                if (tooltips) showTooltip(e, that.parentNode);
            });

            dispatch.on('changeState', function(e) {

                if (typeof e.disabled !== 'undefined' && data.length === e.disabled.length) {
                    data.forEach(function(series,i) {
                        series.disabled = e.disabled[i];
                    });

                    state.disabled = e.disabled;
                }

                chart.update();
            });

        });

        renderWatch.renderEnd('lineChart immediate');
        return chart;
    }

    //============================================================
    // Event Handling/Dispatching (out of chart's scope)
    //------------------------------------------------------------

    lines.dispatch.on('elementMouseover.tooltip', function(e) {
        e.pos = [e.pos[0] +  margin.left, e.pos[1] + margin.top];
        dispatch.tooltipShow(e);
    });

    lines.dispatch.on('elementMouseout.tooltip', function(e) {
        dispatch.tooltipHide(e);
    });

    dispatch.on('tooltipHide', function() {
        if (tooltips) nv.tooltip.cleanup();
    });

    //============================================================
    // Expose Public Variables
    //------------------------------------------------------------

    // expose chart's sub-components
    chart.dispatch = dispatch;
    chart.lines = lines;
    chart.legend = legend;
    chart.xAxis = xAxis;
    chart.yAxis = yAxis;
    chart.interactiveLayer = interactiveLayer;

    chart.dispatch = dispatch;
    chart.options = nv.utils.optionsFunc.bind(chart);

    chart._options = Object.create({}, {
        // simple options, just get/set the necessary values
        width:      {get: function(){return width;}, set: function(_){width=_;}},
        height:     {get: function(){return height;}, set: function(_){height=_;}},
        showLegend: {get: function(){return showLegend;}, set: function(_){showLegend=_;}},
        showXAxis:      {get: function(){return showXAxis;}, set: function(_){showXAxis=_;}},
        showYAxis:    {get: function(){return showYAxis;}, set: function(_){showYAxis=_;}},
        tooltips:    {get: function(){return tooltips;}, set: function(_){tooltips=_;}},
        tooltipContent:    {get: function(){return tooltip;}, set: function(_){tooltip=_;}},
        defaultState:    {get: function(){return defaultState;}, set: function(_){defaultState=_;}},
        noData:    {get: function(){return noData;}, set: function(_){noData=_;}},

// ---
// OTRS
// ---
        reduceXTicks:    {get: function(){return reduceXTicks;}, set: function(_){reduceXTicks=_;}},
        staggerLabels:    {get: function(){return staggerLabels;}, set: function(_){staggerLabels=_;}},
// ---

        // options that require extra logic in the setter
        margin: {get: function(){return margin;}, set: function(_){
            margin.top    = _.top    !== undefined ? _.top    : margin.top;
            margin.right  = _.right  !== undefined ? _.right  : margin.right;
            margin.bottom = _.bottom !== undefined ? _.bottom : margin.bottom;
            margin.left   = _.left   !== undefined ? _.left   : margin.left;
        }},
        duration: {get: function(){return duration;}, set: function(_){
            duration = _;
            renderWatch.reset(duration);
            lines.duration(duration);
            xAxis.duration(duration);
            yAxis.duration(duration);
        }},
        color:  {get: function(){return color;}, set: function(_){
            color = nv.utils.getColor(_);
            legend.color(color);
            lines.color(color);
        }},
        rightAlignYAxis: {get: function(){return rightAlignYAxis;}, set: function(_){
            rightAlignYAxis = _;
            yAxis.orient( rightAlignYAxis ? 'right' : 'left');
        }},
        useInteractiveGuideline: {get: function(){return useInteractiveGuideline;}, set: function(_){
            useInteractiveGuideline = _;
            if (useInteractiveGuideline) {
                lines.interactive(false);
                lines.useVoronoi(false);
            }
        }}
    });

    nv.utils.inheritOptions(chart, lines);
    nv.utils.initOptions(chart);

    return chart;
};
