smart-filename/src/formatFilename.js

NPM package designed for handling filenames safely and effectively. It provides utilities to format, sanitize, validate, truncate, and extract file extensions while ensuring compatibility across different operating systems. This package is particularly us

const path = require('path');
const { removeDiacritics } = require('strip-diacritics');

function formatFilename(filename, options = {}) {
    if (typeof filename !== 'string') return '';

    const {
        separator = '-',
        maxLength = null,
        lowercase = true,
        removeExtension = false
    } = options;

    // Extract filename and extension
    const ext = path.extname(filename);
    let name = path.basename(filename, ext);

    // Normalize text (remove diacritics & unwanted characters)
    name = removeDiacritics(name)
        .replace(/[^a-zA-Z0-9]+/g, separator) // Replace special chars with separator
        .replace(new RegExp(`^${separator}|${separator}$`, 'g'), ''); // Trim extra separators

    // Apply lowercase if needed
    if (lowercase) {
        name = name.toLowerCase();
    }

    // Apply truncation (preserve extension if not removed)
    if (maxLength && name.length > maxLength) {
        name = name.slice(0, maxLength);
    }

    // Return formatted filename with or without extension
    return removeExtension ? name : `${name}${ext}`;
}

module.exports = formatFilename;