1import { common } from '@material-ui/core/colors';
 2import { makeStyles } from '@material-ui/core/styles';
 3import {
 4  getContrastRatio,
 5  darken,
 6} from '@material-ui/core/styles/colorManipulator';
 7import React from 'react';
 8
 9import { LabelFragment } from './fragments.generated';
10import { Color } from '../gqlTypes';
11
12// Minimum contrast between the background and the text color
13const contrastThreshold = 2.5;
14
15// Guess the text color based on the background color
16const getTextColor = (background: string) =>
17  getContrastRatio(background, common.white) >= contrastThreshold
18    ? common.white // White on dark backgrounds
19    : common.black; // And black on light ones
20
21const _rgb = (color: Color) =>
22  'rgb(' + color.R + ',' + color.G + ',' + color.B + ')';
23
24// Create a style object from the label RGB colors
25const createStyle = (color: Color) => ({
26  backgroundColor: _rgb(color),
27  color: getTextColor(_rgb(color)),
28  borderBottomColor: darken(_rgb(color), 0.2),
29});
30
31const useStyles = makeStyles(theme => ({
32  label: {
33    ...theme.typography.body1,
34    padding: '1px 6px 0.5px',
35    fontSize: '0.9em',
36    fontWeight: 500,
37    margin: '0.05em 1px calc(-1.5px + 0.05em)',
38    borderRadius: '3px',
39    display: 'inline-block',
40    borderBottom: 'solid 1.5px',
41    verticalAlign: 'bottom',
42  },
43}));
44
45type Props = { label: LabelFragment };
46function Label({ label }: Props) {
47  const classes = useStyles();
48  return (
49    <span className={classes.label} style={createStyle(label.color)}>
50      {label.name}
51    </span>
52  );
53}
54
55export default Label;