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- export default class Sparkline {
- constructor(element, options = {}) {
- this.element = element;
- this.options = { ...Sparkline.options, ...options };
-
- init: {
- this.element.innerHTML = "<canvas></canvas>";
- this.canvas = this.element.firstChild;
- this.context = this.canvas.getContext("2d");
- this.ratio = window.devicePixelRatio || 1;
-
- if (this.options.tooltip) {
- this.canvas.style.position = "relative";
- this.canvas.addEventListener('mousemove', e => {
- const x = e.offsetX || e.layerX || 0;
- const delta = ((this.options.width - this.options.dotRadius * 2) / (this._points.length - 1));
- const index = minmax(0, Math.round((x - this.options.dotRadius) / delta), this._points.length - 1);
-
- this.canvas.title = this.options.tooltip(this._points[index], index, this._points);
- }, false);
- }
- }
- }
-
- set points(points) {
- this.draw(points);
- }
-
- get points() {
- return this._points;
- }
-
- draw(points = []) {
- this._points = points;
-
- this.canvas.width = this.options.width * this.ratio;
- this.canvas.style.width = `${this.options.width}px`;
-
- const pxHeight = this.options.height || this.element.offsetHeight;
- this.canvas.height = pxHeight * this.ratio;
- this.canvas.style.height = `${pxHeight}px`;
-
- const lineWidth = this.options.lineWidth * this.ratio;
- const offsetX = Math.max(this.options.dotRadius * this.ratio, lineWidth / 2);
- const offsetY = Math.max(this.options.dotRadius * this.ratio, lineWidth / 2);
- const width = this.canvas.width - offsetX * 2;
- const height = this.canvas.height - offsetY * 2;
-
- const minValue = Math.min.apply(Math, points);
- const maxValue = Math.max.apply(Math, points);
- const bottomValue = this.options.minValue != undefined ? this.options.minValue : Math.min(minValue, this.options.maxMinValue != undefined ? this.options.maxMinValue : minValue);
- const topValue = this.options.maxValue != undefined ? this.options.maxValue : Math.max(maxValue, this.options.minMaxValue != undefined ? this.options.minMaxValue : maxValue);
- let minX = offsetX;
- let maxX = offsetX;
-
- let x = offsetX;
- const y = index => (topValue === bottomValue)
- ? offsetY + height / 2
- : (offsetY + height) - ((points[index] - bottomValue) / (topValue - bottomValue)) * height;
- const delta = width / (points.length - 1);
-
- const line = (style, x, y) => {
- if (!style) return;
-
- this.context.save();
- this.context.strokeStyle = style.color || 'black';
- this.context.lineWidth = (style.width || 1) * this.ratio;
- this.context.globalAlpha = style.alpha || 1;
- this.context.beginPath();
- this.context.moveTo(style.direction != 'right' ? offsetX : x, y);
- this.context.lineTo(style.direction != 'left' ? width + offsetX : x, y);
- this.context.stroke();
- this.context.restore();
- }
-
- const dot = (color, lineStyle, x, y) => {
- this.context.beginPath();
- this.context.fillStyle = color;
- this.context.arc(x, y, this.options.dotRadius * this.ratio, 0, Math.PI * 2, false);
- this.context.fill();
- line(lineStyle, x, y);
- }
-
- this.context.save();
-
- this.context.strokeStyle = this.options.lineColor;
- this.context.fillStyle = this.options.lineColor;
- this.context.lineWidth = lineWidth;
- this.context.lineCap = 'round';
- this.context.lineJoin = 'round';
-
- if (this.options.fillBelow && points.length > 1) {
- this.context.save();
- this.context.beginPath();
- this.context.moveTo(x, y(0));
- for (let i = 1; i < points.length; i++) {
- x += delta;
-
- minX = points[i] == minValue ? x : minX;
- maxX = points[i] == maxValue ? x : maxX;
-
- this.context.lineTo(x, y(i));
- }
- this.context.lineTo(width + offsetX, height + offsetY + lineWidth / 2);
- this.context.lineTo(offsetX, height + offsetY + lineWidth / 2);
- this.context.fill();
- if (this.options.fillLighten > 0) {
- this.context.fillStyle = 'white';
- this.context.globalAlpha = this.options.fillLighten;
- this.context.fill();
- this.context.globalAlpha = 1;
- } else if (this.options.fillLighten < 0) {
- this.context.fillStyle = 'black';
- this.context.globalAlpha = -this.options.fillLighten;
- this.context.fill();
- }
- this.context.restore();
- }
-
- x = offsetX;
- this.context.beginPath();
- this.context.moveTo(x, y(0));
- for (let i = 1; i < points.length; i++) {
- x += delta;
- this.context.lineTo(x, y(i));
- }
- this.context.stroke();
-
- this.context.restore();
-
- line(this.options.bottomLine, 0, offsetY);
- line(this.options.topLine, 0, height + offsetY + lineWidth / 2);
-
- dot(this.options.startColor, this.options.startLine, offsetX + (points.length == 1 ? width / 2 : 0), y(0));
- dot(this.options.endColor, this.options.endLine, offsetX + (points.length == 1 ? width / 2 : width), y(points.length - 1));
- dot(this.options.minColor, this.options.minLine, minX + (points.length == 1 ? width / 2 : 0), y(points.indexOf(minValue)));
- dot(this.options.maxColor, this.options.maxLine, maxX + (points.length == 1 ? width / 2 : 0), y(points.indexOf(maxValue)));
- }
-
- static init(element, options) {
- return new Sparkline(element, options);
- }
-
- static draw(element, points, options) {
- const sparkline = new Sparkline(element, options);
- sparkline.draw(points);
- return sparkline;
- }
- }
-
- Sparkline.options = {
- width: 100,
- height: null,
- lineColor: "black",
- lineWidth: 1.5,
- startColor: "transparent",
- endColor: "black",
- maxColor: "transparent",
- minColor: "transparent",
- minValue: null,
- maxValue: null,
- minMaxValue: null,
- maxMinValue: null,
- dotRadius: 2.5,
- tooltip: null,
- fillBelow: true,
- fillLighten: 0.5,
- startLine: false,
- endLine: false,
- minLine: false,
- maxLine: false,
- bottomLine: false,
- topLine: false,
- averageLine: false
- };
-
- function minmax(a, b, c) {
- return Math.max(a, Math.min(b, c));
- }
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