/**
 * 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/>.
 */

import { ROOT_PATH, SERVER } from "../constants.js";

/**
 * 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);
    return bytes.reduce((s, b) => s + b.toString(16).padStart(2, "0"), "").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()
    //Clean the HREF to remove not permitted chars
    currentTxtVal = currentTxtVal.replace(/(?![0-9a-zA-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);
    }
}

/**
 * Make sure HREF is complete including server and prefix.
 * @param {string} href 
 */
export function completeHref(href) {
    let full_href = href;
    if (!href.includes("://")) {
        if (!href.startsWith("/")) {
            full_href = "/" + href;
        }
        // ROOT_PATH ends in / and href starts with /, so remove the duplicate /
        full_href = SERVER + ROOT_PATH + full_href.substring(1);
    }
    return full_href;
}

/**
 * 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];
}


/**
 * Get an element by its ID and throw an error if it's not found.
 * @param {string} id The ID of the element to find.
 * @return {HTMLElement} The found element.
 */
export function get_element_by_id(id) {
    const element = document.getElementById(id);
    if (!element) {
        throw new Error("Element with ID '" + id + "' not found");
    }
    return element;
}

/**
 * Get an element by a selector and throw an error if it's not found.
 * @param {ParentNode} node The parent node to search within.
 * @param {string} selector The CSS selector to use.
 * @return {HTMLElement} The found element.
 */
export function get_element(node, selector) {
    const element = node.querySelector(selector);
    if (!element) {
        throw new Error("Element with selector '" + selector + "' not found");
    }
    return /** @type {HTMLElement} */ (element);
}

/**
 * Trim a string to the given maximum number of characters
 *
 * @param {string} str
 * @param {number} max
 * @returns {string}
 */
export function trim_to_max(str, max) {
    if (str.length > max - 2) {
        return str.substring(0, max) + "...";
    }
    return str;
}