/* eslint-env browser */
const d3 = Object.assign({},
require('d3-selection'),
require('d3-scale'),
require('d3-axis'),
require('d3-shape'));
/**
* Builds a Line Graph.
* @constructor
* @param {String} mode (init / refresh)
* @exports lineGraph
*/
const lineGraph = function chart(mode) {
const svgContainer = d3.select(`#${this.chartData.selector}`);
const cs = {
pallette: {
lineFill: '#ffcdcd',
pointFill: '#005792',
pointStroke: '#d1f4fa',
},
x: {
domain: [],
range: [],
axisHeight: 20,
},
y: {
axisWidth: 30,
ticks: 5,
},
};
/**
* @method enter
* @param {Object} points (svg element)
* @description Runs when a new element is added to the dataset
*/
const enter = (points, path) => {
if (mode === 'init')
path.enter()
.append('path')
.attr('d', cs.lineFunction(this.ds))
.attr('fill', 'none')
.attr('stroke', cs.pallette.lineFill)
.attr('stroke-width', 3);
points.enter()
.append('circle')
.attr('class', this.selector)
.attr('r', 2)
.on('mouseover', (d) => {
this.addTooltip(d, window.event);
})
.on('mouseout', (d) => {
this.removeTooltip(d);
})
.attr('cx', d => cs.x.scale(d.dim) + cs.y.axisWidth + 5)
.attr('cy', d => cs.y.scale(d.metric));
return points;
};
/**
* @method transition
* @param {Object} points (svg element)
* @description Runs when a value of an element in dataset is changed
*/
const transition = (points, path) => {
path.transition()
.attr('d', cs.lineFunction(this.ds));
points.transition()
.attr('cx', d => cs.x.scale(d.dim) + cs.y.axisWidth + 5)
.attr('cy', d => cs.y.scale(d.metric))
.attr('cx', d => cs.x.scale(d.dim) + cs.y.axisWidth + 5)
.attr('cy', d => cs.y.scale(d.metric));
return points;
};
/**
* @method exit
* @param {Object} points (svg element)
* @description Runs when an element is removed from the dataset
*/
const exit = (points, path) => {
points.exit().remove();
path.exit().remove();
return points;
};
/**
* @method buildScales
* @description builds the scales for the x and y axes
*/
const buildScales = () => {
cs.y.scale = d3.scaleLinear()
.domain([this.min, this.max])
.range([this.height - cs.x.axisHeight, this.header]);
cs.y.axis = d3.axisLeft().ticks(cs.y.ticks, 's').scale(cs.y.scale);
this.ds.forEach(t => cs.x.domain.push(t.dim));
this.ds.forEach((t, i) => cs.x.range.push(((this.width * i) - this.header) / this.ds.length));
cs.x.scale = d3.scaleOrdinal().domain(cs.x.domain).range(cs.x.range);
};
/**
* @method drawAxis
* @description draws the x and y axes on the svg
*/
const drawAxis = () => {
cs.x.axis = d3.axisBottom().scale(cs.x.scale);
cs.x.xOffset = cs.y.axisWidth + 5;
cs.x.yOffset = this.height - cs.x.axisHeight;
cs.y.xOffset = cs.y.axisWidth;
cs.y.yOffset = 0;
};
/**
*
* Helper Functions
*/
cs.lineFunction = d3.line()
.x(d => cs.x.scale(d.dim) + cs.y.axisWidth + 5)
.y(d => cs.y.scale(d.metric));
const points = svgContainer.selectAll('circle').data(this.ds);
const path = svgContainer.selectAll('path').data(this.ds);
buildScales(cs);
drawAxis(cs);
enter(points, path);
transition(points,path);
exit(points, path);
svgContainer.append('g').append('g').attr('class', 'axis').attr('transform', `translate(${cs.x.xOffset}, ${cs.x.yOffset})`)
.call(cs.x.axis);
svgContainer.append('g').append('g').attr('class', 'axis').attr('transform', `translate(${cs.y.xOffset},${cs.y.yOffset})`)
.call(cs.y.axis);
};
export default lineGraph;