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: 40, left: 40 };
let colors = palette.categorical(1);
let transition = { ease: d3.easeLinear, duration: 0 };
let dispatch = d3.dispatch("customValueMouseOver", "customValueMouseOut", "customValueClick", "customSeriesMouseOver", "customSeriesMouseOut", "customSeriesClick");
/* Other Customisation Options */
let opacity = 1;
let showAxis = true;
let yAxisLabel = null;
/**
* Constructor
*
* @constructor
* @alias lineChart
* @param {d3.selection} selection - The chart holder D3 selection.
*/
function my(selection) {
selection.each(function(data) {
// Set up margins and dimensions for the chart
const legendW = 120;
const legendPad = 15;
const chartW = Math.max((width - margin.left - legendPad - legendW - margin.right), 100);
const chartH = Math.max((height - margin.top - margin.bottom), 100);
const legendH = Math.max(chartH / 2, 100);
const isTimeSeries = false;
// 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]);
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.key);
});
});
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);
// 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 {
return selection.append("svg");
}
})(selection);
svg.classed("d3ez", true)
.attr("width", width)
.attr("height", height);
// Update the chart dimensions and container and layer groups
const container = svg.selectAll(".container")
.data([data]);
container.exit().remove();
const containerEnter = container.enter()
.append("g")
.classed("container", true)
.classed(classed, true)
.merge(container)
.attr("transform", `translate(${margin.left},${margin.top})`)
.attr("width", chartW)
.attr("height", chartH);
const layers = ["zoomArea", "xAxis axis", "yAxis axis", "chart", "legend"];
containerEnter.selectAll("g")
.data(layers)
.enter()
.append("g")
.attr("class", (d) => d);
// Line Chart Component
const lineChart = component.lineChart()
.colorScale(colorScale)
.xScale(xScale)
.yScale(yScale)
.opacity(opacity)
.dispatch(dispatch);
// Scatter Plot Component
const scatterPlot = component.scatterPlot()
.colorScale(colorScale)
.yScale(yScale)
.xScale(xScale)
.opacity(opacity)
.dispatch(dispatch);
// Series Group
const seriesGroup = containerEnter.select(".chart")
.selectAll(".seriesGroup")
.data((d) => d);
seriesGroup.enter()
.append("g")
.attr("class", "seriesGroup")
.merge(seriesGroup)
.transition()
.ease(transition.ease)
.duration(transition.duration)
.call(lineChart)
.call(scatterPlot);
seriesGroup.exit()
.transition()
.ease(transition.ease)
.duration(transition.duration)
.remove();
// X-Axis
const xAxis = d3.axisBottom(xScale);
containerEnter.select(".xAxis")
.attr("transform", `translate(0,${chartH})`)
.call(xAxis);
// Y-Axis
const yAxis = d3.axisLeft(yScale);
containerEnter.select(".yAxis")
.call(yAxis);
// Y-Axis Label
containerEnter.select(".yAxis")
.selectAll(".yAxisLabel")
.data([yAxisLabel])
.enter()
.append("text")
.classed("yAxisLabel", true)
.attr("transform", "rotate(-90)")
.attr("y", -40)
.attr("dy", ".71em")
.attr("fill", "currentColor")
.style("text-anchor", "end")
.transition()
.text((d) => d);
containerEnter.selectAll(".axis")
.attr("opacity", showAxis ? 1 : 0);
// Legend
const legend = component.legend()
.colorScale(colorScale)
.height(legendH)
.width(legendW)
.itemType("line")
.opacity(opacity);
containerEnter.select(".legend")
.attr("transform", `translate(${chartW + legendPad},0)`)
.call(legend);
});
}
/**
* 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;
};
/**
* Opacity Getter / Setter
*
* @param {Number} _v - Opacity level.
* @returns {*}
*/
my.opacity = function(_v) {
if (!arguments.length) return opacity;
opacity = _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;
};
/**
* 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 Axix Label Getter / Setter
*
* @param {number} _v - Label text.
* @returns {*}
*/
my.yAxisLabel = function(_v) {
if (!arguments.length) return yAxisLabel;
yAxisLabel = _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;
};
/**
* Dispatch On Getter
*
* @returns {*}
*/
my.on = function() {
const value = dispatch.on.apply(dispatch, arguments);
return value === dispatch ? my : value;
};
return my;
}