tooltip.js

/* Tooltip rendering model for nvd3 charts.
 window.nv.models.tooltip is the updated,new way to render tooltips.

 window.nv.tooltip.show is the old tooltip code.
 window.nv.tooltip.* also has various helper methods.
 */
(function() {
    "use strict";
    window.nv.tooltip = {};

    /* Model which can be instantiated to handle tooltip rendering.
     Example usage:
     var tip = nv.models.tooltip().gravity('w').distance(23)
     .data(myDataObject);

     tip();    //just invoke the returned function to render tooltip.
     */
    window.nv.models.tooltip = function() {
        //HTML contents of the tooltip.  If null, the content is generated via the data variable.
        var content = null;

        /*
        Tooltip data. If data is given in the proper format, a consistent tooltip is generated.
        Example Format of data:
        {
            key: "Date",
            value: "August 2009",
            series: [
                {key: "Series 1", value: "Value 1", color: "#000"},
                {key: "Series 2", value: "Value 2", color: "#00f"}
            ]
        }
        */
        var data = null;

        var gravity = 'w'   //Can be 'n','s','e','w'. Determines how tooltip is positioned.
            ,distance = 50   //Distance to offset tooltip from the mouse location.
            ,snapDistance = 25   //Tolerance allowed before tooltip is moved from its current position (creates 'snapping' effect)
            ,   fixedTop = null //If not null, this fixes the top position of the tooltip.
            ,   classes = null  //Attaches additional CSS classes to the tooltip DIV that is created.
            ,   chartContainer = null   //Parent DIV, of the SVG Container that holds the chart.
            ,   tooltipElem = null  //actual DOM element representing the tooltip.
            ,   position = {left: null, top: null}      //Relative position of the tooltip inside chartContainer.
            ,   enabled = true;  //True -> tooltips are rendered. False -> don't render tooltips.

        //Generates a unique id when you create a new tooltip() object
        var id = "nvtooltip-" + Math.floor(Math.random() * 100000);

        //CSS class to specify whether element should not have mouse events.
        var  nvPointerEventsClass = "nv-pointer-events-none";

        //Format function for the tooltip values column
        var valueFormatter = function(d,i) {
            return d;
        };

        //Format function for the tooltip header value.
        var headerFormatter = function(d) {
            return d;
        };

        //By default, the tooltip model renders a beautiful table inside a DIV.
        //You can override this function if a custom tooltip is desired.
        var contentGenerator = function(d) {
            if (content != null) {
                return content;
            }

            if (d == null) {
                return '';
            }

            var table = d3.select(document.createElement("table"));
            var theadEnter = table.selectAll("thead")
                .data([d])
                .enter().append("thead");

            theadEnter.append("tr")
                .append("td")
                .attr("colspan",3)
                .append("strong")
                .classed("x-value",true)
                .html(headerFormatter(d.value));

            var tbodyEnter = table.selectAll("tbody")
                .data([d])
                .enter().append("tbody");

            var trowEnter = tbodyEnter.selectAll("tr")
                    .data(function(p) { return p.series})
                    .enter()
                    .append("tr")
                    .classed("highlight", function(p) { return p.highlight});

            trowEnter.append("td")
                .classed("legend-color-guide",true)
                .append("div")
                .style("background-color", function(p) { return p.color});

            trowEnter.append("td")
                .classed("key",true)
                .html(function(p) {return p.key});

            trowEnter.append("td")
                .classed("value",true)
                .html(function(p,i) { return valueFormatter(p.value,i) });


            trowEnter.selectAll("td").each(function(p) {
                if (p.highlight) {
                    var opacityScale = d3.scale.linear().domain([0,1]).range(["#fff",p.color]);
                    var opacity = 0.6;
                    d3.select(this)
                        .style("border-bottom-color", opacityScale(opacity))
                        .style("border-top-color", opacityScale(opacity))
                    ;
                }
            });

            var html = table.node().outerHTML;
            if (d.footer !== undefined)
                html += "<div class='footer'>" + d.footer + "</div>";
            return html;

        };

        var dataSeriesExists = function(d) {
            if (d && d.series && d.series.length > 0) {
                return true;
            }
            return false;
        };

        //In situations where the chart is in a 'viewBox', re-position the tooltip based on how far chart is zoomed.
        function convertViewBoxRatio() {
            if (chartContainer) {
                var svg = d3.select(chartContainer);
                if (svg.node().tagName !== "svg") {
                    svg = svg.select("svg");
                }
                var viewBox = (svg.node()) ? svg.attr('viewBox') : null;
                if (viewBox) {
                    viewBox = viewBox.split(' ');
                    var ratio = parseInt(svg.style('width')) / viewBox[2];

                    position.left = position.left * ratio;
                    position.top  = position.top * ratio;
                }
            }
        }

        //Creates new tooltip container, or uses existing one on DOM.
        function getTooltipContainer(newContent) {
            var body;
            if (chartContainer) {
                body = d3.select(chartContainer);
            } else {
                body = d3.select("body");
            }

            var container = body.select(".nvtooltip");
            if (container.node() === null) {
                //Create new tooltip div if it doesn't exist on DOM.
                container = body.append("div")
                    .attr("class", "nvtooltip " + (classes? classes: "xy-tooltip"))
                    .attr("id",id)
                ;
            }

            container.node().innerHTML = newContent;
            container.style("top",0).style("left",0).style("opacity",0);
            container.selectAll("div, table, td, tr").classed(nvPointerEventsClass,true)
            container.classed(nvPointerEventsClass,true);
            return container.node();
        }

        //Draw the tooltip onto the DOM.
        function nvtooltip() {
            if (!enabled) return;
            if (!dataSeriesExists(data)) return;

            convertViewBoxRatio();

            var left = position.left;
            var top = (fixedTop != null) ? fixedTop : position.top;
            var container = getTooltipContainer(contentGenerator(data));
            tooltipElem = container;
            if (chartContainer) {
                var svgComp = chartContainer.getElementsByTagName("svg")[0];
                var boundRect = (svgComp) ? svgComp.getBoundingClientRect() : chartContainer.getBoundingClientRect();
                var svgOffset = {left:0,top:0};
                if (svgComp) {
                    var svgBound = svgComp.getBoundingClientRect();
                    var chartBound = chartContainer.getBoundingClientRect();
                    var svgBoundTop = svgBound.top;

                    //Defensive code. Sometimes, svgBoundTop can be a really negative
                    //  number, like -134254. That's a bug.
                    //  If such a number is found, use zero instead. FireFox bug only
                    if (svgBoundTop < 0) {
                        var containerBound = chartContainer.getBoundingClientRect();
                        svgBoundTop = (Math.abs(svgBoundTop) > containerBound.height) ? 0 : svgBoundTop;
                    }
                    svgOffset.top = Math.abs(svgBoundTop - chartBound.top);
                    svgOffset.left = Math.abs(svgBound.left - chartBound.left);
                }
                //If the parent container is an overflow <div> with scrollbars, subtract the scroll offsets.
                //You need to also add any offset between the <svg> element and its containing <div>
                //Finally, add any offset of the containing <div> on the whole page.
                left += chartContainer.offsetLeft + svgOffset.left - 2*chartContainer.scrollLeft;
                top += chartContainer.offsetTop + svgOffset.top - 2*chartContainer.scrollTop;
            }

            if (snapDistance && snapDistance > 0) {
                top = Math.floor(top/snapDistance) * snapDistance;
            }

            nv.tooltip.calcTooltipPosition([left,top], gravity, distance, container);
            return nvtooltip;
        }

        nvtooltip.nvPointerEventsClass = nvPointerEventsClass;

        nvtooltip.content = function(_) {
            if (!arguments.length) return content;
            content = _;
            return nvtooltip;
        };

        //Returns tooltipElem...not able to set it.
        nvtooltip.tooltipElem = function() {
            return tooltipElem;
        };

        nvtooltip.contentGenerator = function(_) {
            if (!arguments.length) return contentGenerator;
            if (typeof _ === 'function') {
                contentGenerator = _;
            }
            return nvtooltip;
        };

        nvtooltip.data = function(_) {
            if (!arguments.length) return data;
            data = _;
            return nvtooltip;
        };

        nvtooltip.gravity = function(_) {
            if (!arguments.length) return gravity;
            gravity = _;
            return nvtooltip;
        };

        nvtooltip.distance = function(_) {
            if (!arguments.length) return distance;
            distance = _;
            return nvtooltip;
        };

        nvtooltip.snapDistance = function(_) {
            if (!arguments.length) return snapDistance;
            snapDistance = _;
            return nvtooltip;
        };

        nvtooltip.classes = function(_) {
            if (!arguments.length) return classes;
            classes = _;
            return nvtooltip;
        };

        nvtooltip.chartContainer = function(_) {
            if (!arguments.length) return chartContainer;
            chartContainer = _;
            return nvtooltip;
        };

        nvtooltip.position = function(_) {
            if (!arguments.length) return position;
            position.left = (typeof _.left !== 'undefined') ? _.left : position.left;
            position.top = (typeof _.top !== 'undefined') ? _.top : position.top;
            return nvtooltip;
        };

        nvtooltip.fixedTop = function(_) {
            if (!arguments.length) return fixedTop;
            fixedTop = _;
            return nvtooltip;
        };

        nvtooltip.enabled = function(_) {
            if (!arguments.length) return enabled;
            enabled = _;
            return nvtooltip;
        };

        nvtooltip.valueFormatter = function(_) {
            if (!arguments.length) return valueFormatter;
            if (typeof _ === 'function') {
                valueFormatter = _;
            }
            return nvtooltip;
        };

        nvtooltip.headerFormatter = function(_) {
            if (!arguments.length) return headerFormatter;
            if (typeof _ === 'function') {
                headerFormatter = _;
            }
            return nvtooltip;
        };

        //id() is a read-only function. You can't use it to set the id.
        nvtooltip.id = function() {
            return id;
        };

        return nvtooltip;
    };

    //Original tooltip.show function. Kept for backward compatibility.
    // pos = [left,top]
    nv.tooltip.show = function(pos, content, gravity, dist, parentContainer, classes) {

        //Create new tooltip div if it doesn't exist on DOM.
        var   container = document.createElement('div');
        container.className = 'nvtooltip ' + (classes ? classes : 'xy-tooltip');

        var body = parentContainer;
        if ( !parentContainer || parentContainer.tagName.match(/g|svg/i)) {
            //If the parent element is an SVG element, place tooltip in the <body> element.
            body = document.getElementsByTagName('body')[0];
        }

        container.style.left = 0;
        container.style.top = 0;
        container.style.opacity = 0;
        // Content can also be dom element
        if (typeof content !== 'string')
            container.appendChild(content);
        else
            container.innerHTML = content;
        body.appendChild(container);

        //If the parent container is an overflow <div> with scrollbars, subtract the scroll offsets.
        if (parentContainer) {
            pos[0] = pos[0] - parentContainer.scrollLeft;
            pos[1] = pos[1] - parentContainer.scrollTop;
        }
        nv.tooltip.calcTooltipPosition(pos, gravity, dist, container);
    };

    //Looks up the ancestry of a DOM element, and returns the first NON-svg node.
    nv.tooltip.findFirstNonSVGParent = function(Elem) {
        while(Elem.tagName.match(/^g|svg$/i) !== null) {
            Elem = Elem.parentNode;
        }
        return Elem;
    };

    //Finds the total offsetTop of a given DOM element.
    //Looks up the entire ancestry of an element, up to the first relatively positioned element.
    nv.tooltip.findTotalOffsetTop = function ( Elem, initialTop ) {
        var offsetTop = initialTop;

        do {
            if( !isNaN( Elem.offsetTop ) ) {
                offsetTop += (Elem.offsetTop);
            }
        } while( Elem = Elem.offsetParent );
        return offsetTop;
    };

    //Finds the total offsetLeft of a given DOM element.
    //Looks up the entire ancestry of an element, up to the first relatively positioned element.
    nv.tooltip.findTotalOffsetLeft = function ( Elem, initialLeft) {
        var offsetLeft = initialLeft;

        do {
            if( !isNaN( Elem.offsetLeft ) ) {
                offsetLeft += (Elem.offsetLeft);
            }
        } while( Elem = Elem.offsetParent );
        return offsetLeft;
    };

    //Global utility function to render a tooltip on the DOM.
    //pos = [left,top] coordinates of where to place the tooltip, relative to the SVG chart container.
    //gravity = how to orient the tooltip
    //dist = how far away from the mouse to place tooltip
    //container = tooltip DIV
    nv.tooltip.calcTooltipPosition = function(pos, gravity, dist, container) {

        var height = parseInt(container.offsetHeight),
            width = parseInt(container.offsetWidth),
            windowWidth = nv.utils.windowSize().width,
            windowHeight = nv.utils.windowSize().height,
            scrollTop = window.pageYOffset,
            scrollLeft = window.pageXOffset,
            left, top;

        windowHeight = window.innerWidth >= document.body.scrollWidth ? windowHeight : windowHeight - 16;
        windowWidth = window.innerHeight >= document.body.scrollHeight ? windowWidth : windowWidth - 16;

        gravity = gravity || 's';
        dist = dist || 20;

        var tooltipTop = function ( Elem ) {
            return nv.tooltip.findTotalOffsetTop(Elem, top);
        };

        var tooltipLeft = function ( Elem ) {
            return nv.tooltip.findTotalOffsetLeft(Elem,left);
        };

        switch (gravity) {
            case 'e':
                left = pos[0] - width - dist;
                top = pos[1] - (height / 2);
                var tLeft = tooltipLeft(container);
                var tTop = tooltipTop(container);
                if (tLeft < scrollLeft) left = pos[0] + dist > scrollLeft ? pos[0] + dist : scrollLeft - tLeft + left;
                if (tTop < scrollTop) top = scrollTop - tTop + top;
                if (tTop + height > scrollTop + windowHeight) top = scrollTop + windowHeight - tTop + top - height;
                break;
            case 'w':
                left = pos[0] + dist;
                top = pos[1] - (height / 2);
                var tLeft = tooltipLeft(container);
                var tTop = tooltipTop(container);
                if (tLeft + width > windowWidth) left = pos[0] - width - dist;
                if (tTop < scrollTop) top = scrollTop + 5;
                if (tTop + height > scrollTop + windowHeight) top = scrollTop + windowHeight - tTop + top - height;
                break;
            case 'n':
                left = pos[0] - (width / 2) - 5;
                top = pos[1] + dist;
                var tLeft = tooltipLeft(container);
                var tTop = tooltipTop(container);
                if (tLeft < scrollLeft) left = scrollLeft + 5;
                if (tLeft + width > windowWidth) left = left - width/2 + 5;
                if (tTop + height > scrollTop + windowHeight) top = scrollTop + windowHeight - tTop + top - height;
                break;
            case 's':
                left = pos[0] - (width / 2);
                top = pos[1] - height - dist;
                var tLeft = tooltipLeft(container);
                var tTop = tooltipTop(container);
                if (tLeft < scrollLeft) left = scrollLeft + 5;
                if (tLeft + width > windowWidth) left = left - width/2 + 5;
                if (scrollTop > tTop) top = scrollTop;
                break;
            case 'none':
                left = pos[0];
                top = pos[1] - dist;
                var tLeft = tooltipLeft(container);
                var tTop = tooltipTop(container);
                break;
        }

        container.style.left = left+'px';
        container.style.top = top+'px';
        container.style.opacity = 1;
        container.style.position = 'absolute';

        return container;
    };

    //Global utility function to remove tooltips from the DOM.
    nv.tooltip.cleanup = function() {

        // Find the tooltips, mark them for removal by this class (so others cleanups won't find it)
        var tooltips = document.getElementsByClassName('nvtooltip');
        var purging = [];
        while(tooltips.length) {
            purging.push(tooltips[0]);
            tooltips[0].style.transitionDelay = '0 !important';
            tooltips[0].style.opacity = 0;
            tooltips[0].className = 'nvtooltip-pending-removal';
        }

        setTimeout(function() {

            while (purging.length) {
                var removeMe = purging.pop();
                removeMe.parentNode.removeChild(removeMe);
            }
        }, 500);
    };

})();