/**
 * This file is part of Radicale Server - Calendar Server
 * Copyright © 2017-2024 Unrud <unrud@outlook.com>
 * Copyright © 2023-2024 Matthew Hana <matthew.hana@gmail.com>
 * Copyright © 2024-2025 Peter Bieringer <pb@bieringer.de>
 * Copyright © 2026-2026 Max Berger <max@berger.name>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/**
 * Escape string for usage in XML
 * @param {string} s
 * @return {string}
 */
export function escape_xml(s) {
    return (s
        .replace(/&/g, "&amp;")
        .replace(/"/g, "&quot;")
        .replace(/'/g, "&apos;")
        .replace(/</g, "&lt;")
        .replace(/>/g, "&gt;"));
}

/**
 * @return {string}
*/
export function random_uuid() {
    return random_hex(8) + "-" + random_hex(4) + "-" + random_hex(4) + "-" + random_hex(4) + "-" + random_hex(12);
}

/**
 * Generate random hex number.
 * @param {number} length
 * @return {string}
 */
export function random_hex(length) {
    let bytes = new Uint8Array(Math.ceil(length / 2));
    window.crypto.getRandomValues(bytes);
    // Fallback for compatibility with older browsers which may not have padStart
    return bytes.reduce((s, b) => {
        let hex = b.toString(16);
        return s + (String.prototype["padStart"] ? hex["padStart"](2, "0") : ("0" + hex).slice(-2));
    }, "").substring(0, length);
}

/**
 * Removed invalid HREF characters for a collection HREF.
 * @param {HTMLInputElement} href_form A valid Input element or an onchange Event of an Input element.
 */
export function cleanHREFinput(href_form) {
    let currentTxtVal = href_form.value.trim().toLowerCase();
    //Clean the HREF to remove not permitted chars
    currentTxtVal = currentTxtVal.replace(/(?![0-9a-z\-\_\.])./g, '');
    //Clean the HREF to remove leading . (would result in hidden directory)
    currentTxtVal = currentTxtVal.replace(/^\./, '');
    href_form.value = currentTxtVal;
}

/**
 * Event listener for cleaning HREF input.
 * @param {Event} event
 */
export function onCleanHREFinput(event) {
    if (event.target instanceof HTMLInputElement) {
        cleanHREFinput(event.target);
    }
}

/**
 * Checks if a proposed HREF for a collection has a valid format and syntax.
 * @param {string} href String of the proposed HREF.
 * @return Boolean results if the HREF is valid.
 */
export function isValidHREF(href) {
    if (href.length < 1) {
        return false;
    }
    if (href.indexOf("/") != -1) {
        return false;
    }

    return true;
}

/**
 * Format bytes to human-readable text.
 * @param {number} bytes Number of bytes.
 * @return Formatted string.
 */
export function bytesToHumanReadable(bytes) {
    if (isNaN(bytes - 0)) {
        return "";
    }
    const units = ['b', 'kb', 'mb', 'gb', 'tb'];
    let i = bytes == 0 ? 0 : Math.floor(Math.log(bytes) / Math.log(1024));
    i = Math.min(i, units.length - 1);
    return Math.round((bytes / Math.pow(1024, i)) * 100) / 100 + ' ' + units[i];
}

/**
 * Add selection handler for input fields with 'selectall' class.
 */
export function setupSelectAll() {
    document.addEventListener("focusin", (event) => {
        if (event.target instanceof HTMLInputElement && event.target.classList.contains("selectall")) {
            event.target.setSelectionRange(0, 99999);
        }
    });
}