less-pager-mini/dist/readKey.js

A scrollable terminal pager for Node.js CLI apps (terminal only)

"use strict";
Object.defineProperty(exports, "__esModule", { value: true });
exports.readKey = readKey;
/**
 * Reads a single keypress from the terminal asynchronously.
 *
 * - Handles escape sequences by combining `\x1B` with the following character.
 * - Times out after 50ms to detect standalone ESC key.
 * - Requires the terminal to be in TTY mode.
 *
 * @returns A promise that resolves to the pressed key string.
 * @throws If the terminal is not interactive (non-TTY).
 */
async function readKey() {
    if (!process.stdin.isTTY) {
        throw new Error('Interactive terminal (TTY) is required to use this feature.');
    }
    return new Promise(resolve => {
        const resolveKey = (key) => {
            process.stdin.removeListener('data', keyListener);
            clearTimeout(timer);
            resolve(key);
        };
        let timer;
        const keyListener = (key) => {
            if (timer) {
                resolveKey('\x1B' + key);
            }
            if (key !== '\x1B')
                resolveKey(key);
            timer = setTimeout(() => {
                resolveKey('\x1B');
            }, 50);
        };
        process.stdin.on('data', keyListener);
    });
}