generate-github-markdown-css/cli.js

Generate the CSS for github-markdown-css

#!/usr/bin/env node
import {exit} from 'node:process';
import meow from 'meow';
import githubMarkdownCss from './index.js';

const cli = meow(
	`
  Usage
    github-markdown-css > <filename>

  Options
    --list                List available themes

    Set theme:
    --light               Light theme name from --list values
    --dark                Dark theme name from --list values
    --theme               Theme name: 'auto', light', 'dark', or another from --list values.
                          'auto' means using the media query (prefers-color-scheme)
                          to switch between the 'light' and 'dark' theme.

    Output options:
    --preserve-variables   Preserve variables in the output. Only applies if light
                           and dark themes match or if type is not 'auto'
    --only-style           Only output the styles, forces --preserve-variables on
    --only-variables       Only output the variables for the specified themes
    --root-selector        Specify the root selector when outputting styles, default '.markdown-body'
    --no-use-fixture       Exclude generated classes that come from GitHub Markdown API rendered fixture.md

  Examples
    $ github-markdown-css --list
    light
    dark
    dark_dimmed
    dark_high_contrast
    dark_colorblind
    light_colorblind

    $ github-markdown-css --light=light --dark=dark
    [CSS with variable blocks for 'light' and 'dark' themes]

    $ github-markdown-css --theme=dark_dimmed --only-variables
    [CSS with single variable block for 'dark_dimmed' theme with no element styles]

    $ github-markdown-css --only-style
    [CSS with only element styles using variables but no variables set.
      Use in combination with output from setting --only-variables]
`,
	{
		importMeta: import.meta,
		flags: {
			theme: {
				type: 'string',
				aliases: [
					'type',
				],
			},
			light: {
				type: 'string',
			},
			dark: {
				type: 'string',
			},
			list: {
				type: 'boolean',
			},
			onlyStyle: {
				type: 'boolean',
			},
			onlyVariables: {
				type: 'boolean',
			},
			preserveVariables: {
				type: 'boolean',
			},
			rootSelector: {
				type: 'string',
			},
			useFixture: {
				type: 'boolean',
				default: true,
			},
		},
	},
);

const {
	theme,
	list,
	preserveVariables,
	onlyStyle,
	onlyVariables,
	rootSelector,
	useFixture,
} = cli.flags;

let {light, dark} = cli.flags;

/*
| Theme | Light | Dark | Outcome                            |
| ----- | ----- | ---- | ---------------------------------- |
| ✓     |       |      | Single mode, use Theme             |
| ✓     | ✓     |      | Not allowed, can't determine theme |
| ✓     |       | ✓    | Not allowed, can't determine theme |
| ✓     | ✓     | ✓    | Not allowed, can't determine theme |
|       |       |      | Auto, default themes               |
|       | ✓     |      | Single mode, use Light             |
|       |       | ✓    | Single mode, use Dark              |
|       | ✓     | ✓    | Auto, use Light and Dark           |
|       | ✓     | ✓    | Single mode if Light === Dark      |
| auto  |       |      | Auto, default themes               |
| auto  | ✓     |      | Auto, use Light, default dark      |
| auto  |       | ✓    | Auto, use Dark, default light      |
| auto  | ✓     | ✓    | Auto, use Light and Dark           |
| auto  | ✓     | ✓    | Single mode if Light === Dark      |
*/

// Use "single" mode when type is a theme name other than 'auto'
if (theme && theme !== 'auto') {
	if (light || dark) {
		console.error('You may not specify light and/or dark unless type/theme is set to "auto"');
		exit(1);
	}

	light = theme;
	dark = theme;
}

// If only light or dark was specified set the other to force "single mode"
if (!theme && light && !dark) {
	dark = light;
} else if (!theme && !light && dark) {
	light = dark;
}

if (rootSelector === '') {
	console.error('--rootSelector cannot be an empty string');
	exit(1);
}

console.log(
	await githubMarkdownCss({
		light,
		dark,
		list,
		preserveVariables,
		onlyStyles: onlyStyle,
		onlyVariables,
		rootSelector,
		useFixture,
	}),
);