cli.js

#!/usr/bin/env node
import process from 'node:process';
import meow from 'meow';
import getStdin from 'get-stdin';
import boxen, {_borderStyles} from 'boxen';
import indentString from 'indent-string';

const cli = meow(`
	Usage
	  $ boxen <string>
	  $ echo <string> | boxen

	Options
	  --border-color      Color of the box border [black|red|green|yellow|blue|magenta|cyan|white|gray]
	  --background-color  Color of the background [black|red|green|yellow|blue|magenta|cyan|white]
	  --border-style      Style of the box border [single|double|round|singleDouble|doubleSingle|classic]
	                      Can also be specified as the characters to use. See below example.
	  --dim-border        Reduce opacity of border
	  --padding           Space between the text and box border
	  --margin            Space around the box
	  --center            Center the box
	  --text-alignment    Align the text [left|center|right] (Default: left)
	  --title             Display a title at the top of the box
	  --title-alignment   Align the title in the top bar [left|center|right]
	  --width             Set a fixed width for the box
	  --height            Set a fixed height for the box
	  --fullscreen        Fit all available space within the terminal

	Examples
	  $ boxen I ❤ unicorns
	  ┌────────────┐
	  │I ❤ unicorns│
	  └────────────┘

	  $ boxen --border-style=doubleSingle …like everyone
	  ╒══════════════╕
	  │…like everyone│
	  ╘══════════════╛

	  $ boxen --border-style='1234-~|║' ASCII ftw!
	  1----------2
	  |ASCII ftw!║
	  3~~~~~~~~~~4

	  $ boxen --align=center --width=16 'Rainbows are so cool!'
	  ┌──────────────┐
	  │ Rainbows are │
	  │   so cool!   │
	  └──────────────┘

	  $ boxen --title='Yes it is' --title-alignment=center 'Is that a centered title?'
	  ┌─────── Yes it is ───────┐
	  │Is that a centered title?│
	  └─────────────────────────┘
`, {
	importMeta: import.meta,
	flags: {
		borderColor: {
			type: 'string',
		},
		backgroundColor: {
			type: 'string',
		},
		borderStyle: {
			type: 'string',
		},
		dimBorder: {
			type: 'boolean',
		},
		padding: {
			type: 'number',
		},
		margin: {
			type: 'number',
		},
		center: {
			type: 'boolean',
		},
		align: {
			type: 'string',
		},
		title: {
			type: 'string',
		},
		titleAlignment: {
			type: 'string',
		},
		width: {
			type: 'number',
		},
		height: {
			type: 'number',
		},
		fullscreen: {
			type: 'boolean',
		},
	},
});

const {input} = cli;

function cleanupBorderStyle(borderStyle) {
	if (!borderStyle) {
		return 'single';
	}

	if (borderStyle in _borderStyles) {
		return borderStyle;
	}

	// Convert old borderStyle format (6 characters) to new one (8 characters)
	if (borderStyle.length === 6) {
		borderStyle = borderStyle.slice(0, 5) + borderStyle[4] + borderStyle[5].repeat(2);
	}

	// A string of 8 characters was given, make it a borderStyle object
	if (borderStyle.length === 8) {
		return {
			topLeft: borderStyle[0],
			topRight: borderStyle[1],
			bottomLeft: borderStyle[2],
			bottomRight: borderStyle[3],
			top: borderStyle[4],
			bottom: borderStyle[5],
			left: borderStyle[6],
			right: borderStyle[7],
		};
	}

	console.error('Specified custom border style is invalid');
	process.exit(1);
}

function parseMargin(options) {
	if (!options.margin) {
		return;
	}

	if (options.center) {
		return {
			top: options.margin,
			bottom: options.margin,
		};
	}

	return options.margin;
}

function calculateBoxLength(box, options) {
	const lineNumber = options.margin ? options.margin.top || options.margin : 0;
	return box.split('\n')[lineNumber].length;
}

function init(data) {
	cli.flags.borderStyle = cleanupBorderStyle(cli.flags.borderStyle);
	cli.flags.margin = parseMargin(cli.flags);
	let box = boxen(data, cli.flags);

	if (cli.flags.center) {
		const boxLength = calculateBoxLength(box, cli.flags);
		box = indentString(box, (process.stdout.columns - boxLength) / 2);
	}

	console.log(box);
}

if (input.length === 0 && process.stdin.isTTY) {
	console.error('Specify a string');
	process.exit(1);
}

(async () => {
	if (input.length > 0) {
		init(input.join(' '));
	} else {
		const stdin = await getStdin();
		init(stdin.replace(/\n$/, ''));
	}
})();