import * as d3 from "d3";
import component from "../component.js";
import palette from "../palette.js";
import dataTransform from "../dataTransform.js";
/**
* Line Chart (aks: Line Graph; Spline Chart)
*
* @module
* @see http://datavizproject.com/data-type/line-chart/
* @see https://www.atlassian.com/data/charts/line-chart-complete-guide
*/
export default function() {
/* Default Properties */
let classed = "lineChart";
let width = 700;
let height = 400;
let margin = { top: 40, right: 40, bottom: 70, left: 70 };
let colors = palette.categorical(1);
let transition = { ease: d3.easeLinear, duration: 100 };
let dispatch = d3.dispatch("customValueMouseOver", "customValueMouseOut", "customValueClick", "customSeriesMouseOver", "customSeriesMouseOut", "customSeriesClick");
/* Other Customisation Options */
let title = null;
let subTitle = null;
let legendTitle = "Key";
let opacity = 1;
let showLegend = false;
let showAxis = true;
let yAxisLabel = null;
/**
* Constructor
*
* @constructor
* @alias lineChart
* @param {d3.selection} selection - The chart holder D3 selection.
*/
function my(selection) {
// Create SVG element (if it does not exist already)
const svg = (function(selection) {
const el = selection._groups[0][0];
if (!!el.ownerSVGElement || el.tagName === "svg") {
return selection;
} else {
let svgSelection = selection.selectAll("svg").data((d) => [d]);
return svgSelection.enter().append("svg").merge(svgSelection);
}
})(selection);
selection.each(function(data) {
// Set up margins and dimensions for the chart
const legendW = showLegend ? 120 : 0;
const legendH = Math.max(height / 2.5, 100);
const legendPad = showLegend ? 15 : 0;
const titleH = title ? 40 : 0;
const chartW = Math.max((width - margin.left - legendPad - legendW - margin.right), 100);
const chartH = Math.max((height - margin.top - margin.bottom - titleH), 100);
// Create Scales and Axis
let { rowKeys, columnKeys, valueMin, valueMax } = dataTransform(data).summary();
// Set min to zero if min is more than zero
valueMin = valueMin > 0 ? 0 : valueMin;
const valueExtent = [valueMin, valueMax];
let xScale = d3.scalePoint()
.domain(columnKeys)
.range([0, chartW]);
// Zoom does not work with non-time series (scalePoint)
function isTimeSeriesData(data) {
let dateString = data[0].values[0].date
let dateObject = new Date(dateString);
return !isNaN(dateObject.getTime());
}
const isTimeSeries = isTimeSeriesData(data);
if (isTimeSeries) {
// TODO: Use dataTransform() to calculate date domains?
data.forEach((d, i) => {
d.values.forEach((b, j) => {
data[i].values[j].key = new Date(b.date);
});
});
const dateExtent = d3.extent(data[0].values, (d) => d.key);
xScale = d3.scaleTime()
.domain(dateExtent)
.range([0, chartW]);
}
const yScale = d3.scaleLinear()
.domain(valueExtent)
.range([chartH, 0])
.nice();
const colorScale = d3.scaleOrdinal()
.domain(rowKeys)
.range(colors);
// Add Title, Chart and Legend main layer groups
const mainLayers = ["title", "chart", "legend"];
svg.classed("d3ez", true)
.attr("width", width)
.attr("height", height)
.selectAll("g")
.data(mainLayers)
.enter()
.append("g")
.attr("class", (d) => d);
const titleSelect = svg.select(".title");
const chartSelect = svg.select(".chart");
const legendSelect = svg.select(".legend");
// Update the chart dimensions and layer groups
const chartLayers = ["xAxis axis", "yAxis axis", "seriesGroup", "zoomArea", "clipArea"];
chartSelect.classed(classed, true)
.attr("width", chartW)
.attr("height", chartH)
.attr("transform", `translate(${margin.left},${margin.top + titleH})`)
.selectAll("g")
.data(chartLayers)
.enter()
.append("g")
.attr("class", (d) => d);
// Line Chart Component
const componentLineChart = component.lineChart()
.colorScale(colorScale)
.xScale(xScale)
.yScale(yScale)
.opacity(opacity)
.dispatch(dispatch)
.transition(transition);
// Line Dots Component
const componentScatterPlot = component.scatterPlot()
.colorScale(colorScale)
.yScale(yScale)
.xScale(xScale)
.opacity(opacity)
.dispatch(dispatch)
.transition(transition);
// Series Group
const series = chartSelect.select(".seriesGroup")
.selectAll(".series")
.data(data);
series.enter()
.append("g")
.attr("class", "series")
.attr('clip-path', "url(#plotAreaClip)")
.merge(series)
.attr("data-name", (d) => d.key)
.call(componentLineChart)
.call(componentScatterPlot);
series.exit()
.remove();
// Axis
const xAxis = d3.axisBottom(xScale);
const yAxis = d3.axisLeft(yScale);
if (showAxis) {
// X-Axis
chartSelect.select(".xAxis")
.attr("transform", `translate(0,${chartH})`)
.call(xAxis);
// Y-Axis
chartSelect.select(".yAxis")
.call(yAxis);
// Y-Axis Label
chartSelect.select(".yAxis")
.selectAll(".yAxisLabel")
.data([yAxisLabel])
.enter()
.append("text")
.classed("yAxisLabel", true)
.attr("transform", "rotate(-90)")
.attr("y", -40)
.attr("dy", ".71em")
.attr("fill", "currentColor")
.style("text-anchor", "end")
.text((d) => d);
} else {
chartSelect.selectAll(".axis").selectAll('*').remove();
}
// Zoom Clip Path
const clipPath = chartSelect.select(".clipArea")
.selectAll("defs")
.data([0]);
clipPath.enter()
.append("defs")
.append("clipPath")
.attr("id", "plotAreaClip")
.append("rect")
.attr("width", chartW)
.attr("height", chartH)
.merge(clipPath)
.select("clipPath")
.select("rect")
.attr("width", chartW)
.attr("height", chartH);
// Zoom Event Area
const zoom = d3.zoom()
.extent([[0, 0], [chartW, chartH]])
.scaleExtent([1, 8])
.translateExtent([[0, 0], [chartW, chartH]])
.on("zoom", zoomed);
function zoomed(e) {
const xScaleZoomed = e.transform.rescaleX(xScale);
if (showAxis) {
xAxis.scale(xScaleZoomed);
chartSelect.select(".xAxis")
.call(xAxis);
}
componentLineChart
.xScale(xScaleZoomed)
.transition({ ease: d3.easeLinear, duration: 0 });
componentScatterPlot
.xScale(xScaleZoomed)
.transition({ ease: d3.easeLinear, duration: 0 });
chartSelect.select(".seriesGroup")
.selectAll(".series")
.call(componentLineChart)
.call(componentScatterPlot);
}
if (isTimeSeries) {
const zoomArea = chartSelect.select(".zoomArea")
.selectAll("rect")
.data([0]);
zoomArea.enter()
.append("rect")
.attr("fill", "none")
.attr("pointer-events", "all")
.merge(zoomArea)
.call(zoom)
.attr("width", chartW)
.attr("height", chartH);
}
// Title
if (title) {
const componentTitle = component.title()
.mainText(title)
.subText(subTitle);
titleSelect.attr("transform", `translate(${width / 2},${margin.top})`)
.call(componentTitle);
} else {
titleSelect.selectAll("*").remove();
}
// Legend
if (showLegend) {
const componentLegend = component.legend()
.colorScale(colorScale)
.height(legendH)
.width(legendW)
.itemType("line")
.opacity(opacity);
legendSelect.attr("transform", `translate(${margin.left + chartW + legendPad},${margin.top})`)
.call(componentLegend);
} else {
legendSelect.selectAll("*").remove();
}
});
}
/**
* Width Getter / Setter
*
* @param {number} _v - Width in px.
* @returns {*}
*/
my.width = function(_v) {
if (!arguments.length) return width;
width = _v;
return this;
};
/**
* Height Getter / Setter
*
* @param {number} _v - Height in px.
* @returns {*}
*/
my.height = function(_v) {
if (!arguments.length) return height;
height = _v;
return this;
};
/**
* Margin Getter / Setter
*
* @param {number} _v - Margin in px.
* @returns {*}
*/
my.margin = function(_v) {
if (!arguments.length) return margin;
margin = _v;
return this;
};
/**
* Colors Getter / Setter
*
* @param {Array} _v - Array of colours used by color scale.
* @returns {*}
*/
my.colors = function(_v) {
if (!arguments.length) return colors;
colors = _v;
return this;
};
/**
* Show Legend Getter / Setter
*
* @param {Boolean} _v - Show legend true / false.
* @returns {*}
*/
my.showLegend = function(_v) {
if (!arguments.length) return showLegend;
showLegend = _v;
return this;
};
/**
* Title Getter / Setter
*
* @param {string} _v - Title text.
* @returns {*}
*/
my.title = function(_v) {
if (!arguments.length) return title;
title = _v;
return this;
};
/**
* SubTitle Getter / Setter
*
* @param {string} _v - SubTitle text.
* @returns {*}
*/
my.subTitle = function(_v) {
if (!arguments.length) return subTitle;
subTitle = _v;
return this;
};
/**
* Opacity Getter / Setter
*
* @param {Number} _v - Opacity level.
* @returns {*}
*/
my.opacity = function(_v) {
if (!arguments.length) return opacity;
opacity = _v;
return this;
};
/**
* Show Axis Getter / Setter
*
* @param {Boolean} _v - Show axis true / false.
* @returns {*}
*/
my.showAxis = function(_v) {
if (!arguments.length) return showAxis;
showAxis = _v;
return this;
};
/**
* Y-Axis Label Getter / Setter
*
* @param {number} _v - Label text.
* @returns {*}
*/
my.yAxisLabel = function(_v) {
if (!arguments.length) return yAxisLabel;
yAxisLabel = _v;
return this;
};
/**
* Transition Getter / Setter
*
* @param {d3.transition} _v - D3 transition style.
* @returns {*}
*/
my.transition = function(_v) {
if (!arguments.length) return transition;
transition = _v;
return this;
};
/**
* Dispatch Getter / Setter
*
* @param {d3.dispatch} _v - Dispatch event handler.
* @returns {*}
*/
my.dispatch = function(_v) {
if (!arguments.length) return dispatch();
dispatch = _v;
return this;
};
/**
* On Event Getter
*
* @returns {*}
*/
my.on = function() {
const value = dispatch.on.apply(dispatch, arguments);
return value === dispatch ? my : value;
};
return my;
}