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/* eslint no-console: 0 */

import { scaleLinear, scaleLog } from 'd3-scale';

import createScatterplot from '../src';

import { saveAsPng } from './utils';

const canvas = document.querySelector('#canvas');

const canvasWrapper = document.querySelector('#canvas-wrapper');

const numPointsEl = document.querySelector('#num-points');

const numPointsValEl = document.querySelector('#num-points-value');

const pointSizeEl = document.querySelector('#point-size');

const pointSizeValEl = document.querySelector('#point-size-value');

const opacityEl = document.querySelector('#opacity');

const opacityValEl = document.querySelector('#opacity-value');

const clickLassoInitiatorEl = document.querySelector('#click-lasso-initiator');

const resetEl = document.querySelector('#reset');

const exportEl = document.querySelector('#export');

const exampleEl = document.querySelector('#example-text-overlay');

exampleEl.setAttribute('class', 'active');

exampleEl.removeAttribute('href');

const noteEl = document.createElement('div');

noteEl.id = 'note';

noteEl.textContent = 'Zoom in to see labels!';

canvasWrapper.appendChild(noteEl);

const textOverlayEl = document.createElement('canvas');

textOverlayEl.id = '#text-overlay';

textOverlayEl.style.position = 'absolute';

textOverlayEl.style.top = 0;

textOverlayEl.style.right = 0;

textOverlayEl.style.bottom = 0;

textOverlayEl.style.left = 0;

textOverlayEl.style.pointerEvents = 'none';

canvasWrapper.appendChild(textOverlayEl);

const resizeTextOverlay = () => {

const { width, height } = canvasWrapper.getBoundingClientRect();

textOverlayEl.width = width * window.devicePixelRatio;

textOverlayEl.height = height * window.devicePixelRatio;

textOverlayEl.style.width = `${width}px`;

textOverlayEl.style.height = `${height}px`;

};

resizeTextOverlay();

window.addEventListener('resize', resizeTextOverlay);

const overlayFontSize = 12;

const textOverlayCtx = textOverlayEl.getContext('2d');

textOverlayCtx.font = `${

overlayFontSize * window.devicePixelRatio

}px sans-serif`;

textOverlayCtx.textAlign = 'center';

let points = [];

let numPoints = 10000;

let pointSize = 4;

let opacity = 1.0;

let selection = [];

const maxPointLabels = 200;

const lassoMinDelay = 10;

const lassoMinDist = 2;

const showReticle = true;

const reticleColor = [1, 1, 0.878431373, 0.33];

const scatterplot = createScatterplot({

canvas,

lassoMinDelay,

lassoMinDist,

pointSize,

showReticle,

reticleColor,

xScale: scaleLinear().domain([-1, 1]),

yScale: scaleLinear().domain([-1, 1]),

pointColor: '#fff',

opacityBy: 'density',

lassoInitiator: true,

});

exportEl.addEventListener('click', () => saveAsPng(scatterplot));

console.log(`Scatterplot v${scatterplot.get('version')}`);

scatterplot.subscribe('select', ({ points: selectedPoints }) => {

console.log('Selected:', selectedPoints);

selection = selectedPoints;

if (selection.length === 1) {

const point = points[selection[0]];

console.log(

`X: ${point[0]}\nY: ${point[1]}\nCategory: ${point[2]}\nValue: ${point[3]}`

);

}

});

scatterplot.subscribe('deselect', () => {

selection = [];

});

const showPointLabels = (pointsInView, xScale, yScale) => {

textOverlayCtx.clearRect(0, 0, canvas.width, canvas.height);

textOverlayCtx.fillStyle = 'rgb(255, 255, 255)';

for (let i = 0; i < pointsInView.length; i++) {

textOverlayCtx.fillText(

pointsInView[i],

xScale(points[pointsInView[i]][0]) * window.devicePixelRatio,

yScale(points[pointsInView[i]][1]) * window.devicePixelRatio -

overlayFontSize * 1.2 * window.devicePixelRatio

);

}

};

const hidePointLabels = () => {

textOverlayCtx.clearRect(0, 0, canvas.width, canvas.height);

};

scatterplot.subscribe('view', ({ xScale, yScale }) => {

const pointsInView = scatterplot.get('pointsInView');

if (pointsInView.length <= maxPointLabels) {

showPointLabels(pointsInView, xScale, yScale);

} else {

hidePointLabels();

}

});

const generatePoints = (num) =>

Array.from({ length: num }, () => [

-1 + Math.random() * 2,

-1 + Math.random() * 2,

]);

const setNumPoint = (newNumPoints) => {

numPoints = newNumPoints;

numPointsEl.value = numPoints;

numPointsValEl.innerHTML = numPoints;

points = generatePoints(numPoints);

scatterplot.draw(points);

};

const numPointsInputHandler = (event) => {

numPointsValEl.innerHTML = `${+event.target

.value} <em>release to redraw</em>`;

};

numPointsEl.addEventListener('input', numPointsInputHandler);

const numPointsChangeHandler = (event) => setNumPoint(+event.target.value);

numPointsEl.addEventListener('change', numPointsChangeHandler);

const getPointSizeRange = (basePointSize) => {

const pointSizeScale = scaleLog()

.domain([1, 10])

.range([basePointSize, basePointSize * 10]);

return Array(100)

.fill()

.map((x, i) => pointSizeScale(1 + (i / 99) * 9));

};

const setPointSize = (newPointSize) => {

pointSize = newPointSize;

pointSizeEl.value = pointSize;

pointSizeValEl.innerHTML = pointSize;

scatterplot.set({ pointSize: getPointSizeRange(pointSize) });

};

const pointSizeInputHandler = (event) => setPointSize(+event.target.value);

pointSizeEl.addEventListener('input', pointSizeInputHandler);

const getOpacityRange = (baseOpacity) =>

Array(10)

.fill()

.map((x, i) => ((i + 1) / 10) * baseOpacity);

const setOpacity = (newOpacity) => {

opacity = newOpacity;

opacityEl.value = opacity;

opacityValEl.innerHTML = opacity;

scatterplot.set({ opacity: getOpacityRange(opacity) });

};

const opacityInputHandler = (event) => setOpacity(+event.target.value);

opacityEl.addEventListener('input', opacityInputHandler);

const clickLassoInitiatorChangeHandler = (event) => {

scatterplot.set({

lassoInitiator: event.target.checked,

});

};

clickLassoInitiatorEl.addEventListener(

'change',

clickLassoInitiatorChangeHandler

);

clickLassoInitiatorEl.checked = scatterplot.get('lassoInitiator');

const resetClickHandler = () => {

scatterplot.reset();

};

resetEl.addEventListener('click', resetClickHandler);

setPointSize(pointSize);

setOpacity(opacity);

setNumPoint(numPoints);