ls.js

#!/usr/bin/env node
const fs = require('node:fs');
const path = require('node:path');

function listDirectory(dirPath, showAll, onePerLine) {
    try {
        const entries = fs.readdirSync(dirPath, { withFileTypes: true });
        const filtered = entries.filter((entry) => showAll || !entry.name.startsWith('.'));

        if(onePerLine) {
            filtered.forEach(entry => console.log(entry.name));
        } else {
            const names = filtered.map(entry => entry.name);
            console.log(names.join('  '));
        }
        } catch (error) {
        console.error(`Error reading directory ${dirPath}: ${error.message}`);
    }
}
function main() {
    const args = process.argv.slice(2);
    // Check for options
    const showAll = args.includes('-a');
    const onePerLine = args.includes('-1');
    //remove options from args 
    const directories = args.filter(arg => arg !== '-a' && arg !== '-1');

    // If no directory is specified, list the current directory
    if(directories.length === 0) {
        listDirectory(process.cwd(), showAll, onePerLine);
        return;
    }
    //If a directory is specified, list that directory
    directories.forEach((arg, index) => {
        try {
            const stats = fs.statSync(arg);
            if(stats.isDirectory()) {
                //Print header if multiple directories are listed
                if(directories.length > 1) console.log(`${arg}:`);
                
                listDirectory(arg, showAll, onePerLine);
                //add a blank line between directory listings if there are multiple directories
                if(directories.length > 1 && index < directories.length - 1) console.log('');
            } else{
                console.log(arg);// single file
            }
        } catch (error) {
            console.error(`Error accessing ${arg}: ${error.message}`);
        }
    });
}
main();