// ==UserScript==
// @name         VLA Toolkit — Copy/Paste & Session Keep-Alive
// @namespace    https://github.com/COMPLEXWASTAKEN/vla-tampermonkey
// @version      1.4.0
// @description  Unlocks copy/paste on Virtual Learning Academy lesson questions and keeps your session alive automatically.
// @author       COMPLEXWASTAKEN
// @license      MIT
// @homepageURL  https://github.com/COMPLEXWASTAKEN/vla-tampermonkey#readme
// @supportURL   https://github.com/COMPLEXWASTAKEN/vla-tampermonkey/issues
// @updateURL    https://raw.githubusercontent.com/COMPLEXWASTAKEN/vla-tampermonkey/main/vla-enable-copy-paste.user.js
// @downloadURL  https://raw.githubusercontent.com/COMPLEXWASTAKEN/vla-tampermonkey/main/vla-enable-copy-paste.user.js
// @match        https://virtuallearningacademy.net/Student/*
// @match        https://www.virtuallearningacademy.net/Student/*
// @run-at       document-start
// @grant        none
// @inject-into  page
// ==/UserScript==

(function () {
    'use strict';

    const isRealPage = (doc) => {
        const href = doc?.location?.href || '';
        return href && href !== 'about:blank' && !href.startsWith('about:');
    };

    const injectPageScript = (doc, source, markerName) => {
        if (!doc?.documentElement) {
            return false;
        }
        const href = doc.location?.href || 'top';
        const markerKey = 'data-vla-' + markerName;
        if (doc.documentElement.getAttribute(markerKey) === href) {
            return false;
        }
        doc.documentElement.setAttribute(markerKey, href);
        const script = doc.createElement('script');
        script.textContent = source;
        (doc.head || doc.documentElement).appendChild(script);
        script.remove();
        return true;
    };

    const unlockSource = String.raw`(() => {
        const href = location.href;

        if (!href || href === 'about:blank' || href.startsWith('about:')) {
            return;
        }

        const initKey = 'data-vla-unlock-init';
        if (document.documentElement.getAttribute(initKey) === href) {
            return;
        }
        document.documentElement.setAttribute(initKey, href);

        const noopAllow = () => true;
        const clipboardEvents = new Set(['copy', 'cut', 'paste', 'selectstart', 'contextmenu']);

        const lockBlocker = (name) => {
            try {
                Object.defineProperty(window, name, {
                    configurable: true,
                    writable: false,
                    value: noopAllow
                });
            } catch (e) {
                window[name] = noopAllow;
            }
        };

        ['blockCopy', 'blockPaste', 'blockCtrlKeys'].forEach(lockBlocker);

        const origPreventDefault = Event.prototype.preventDefault;
        Event.prototype.preventDefault = function () {
            if (clipboardEvents.has(this.type)) {
                return;
            }
            return origPreventDefault.call(this);
        };

        const style = document.createElement('style');
        style.id = 'vla-unlock-copy';
        style.textContent = [
            'body, body * {',
            '-webkit-user-select: text !important;',
            '-moz-user-select: text !important;',
            '-ms-user-select: text !important;',
            'user-select: text !important;',
            '}'
        ].join('\n');

        const injectStyle = () => {
            if (!document.getElementById('vla-unlock-copy')) {
                (document.head || document.documentElement).appendChild(style);
            }
        };

        const unlockElement = (el) => {
            el.classList.remove('no-copy');
            el.removeAttribute('oncopy');
            el.removeAttribute('oncut');
            el.removeAttribute('onpaste');
            el.removeAttribute('oncontextmenu');
            el.removeAttribute('onselectstart');
            el.removeAttribute('ondragstart');
            el.style.setProperty('-webkit-user-select', 'text', 'important');
            el.style.setProperty('user-select', 'text', 'important');
        };

        const unlockPage = () => {
            injectStyle();
            ['blockCopy', 'blockPaste', 'blockCtrlKeys'].forEach(lockBlocker);
            document.querySelectorAll('.no-copy, [oncopy], [oncut], [onpaste], [oncontextmenu], [onselectstart]').forEach(unlockElement);
        };

        if (document.readyState === 'loading') {
            document.addEventListener('DOMContentLoaded', unlockPage);
        } else {
            unlockPage();
        }

        new MutationObserver(unlockPage).observe(document.documentElement, {
            childList: true,
            subtree: true,
            attributes: true,
            attributeFilter: ['class', 'oncopy', 'oncut', 'onpaste', 'oncontextmenu', 'onselectstart']
        });
    })();`;

    const keepAliveSource = String.raw`(() => {
        if (window.__vlaKeepAliveActive) {
            return;
        }
        window.__vlaKeepAliveActive = true;

        const isWarningVisible = () => {
            const overlay = document.getElementById('timeOutWarningOverlay');
            return overlay && window.getComputedStyle(overlay).display !== 'none';
        };

        const clickStaySignedIn = () => {
            if (!isWarningVisible()) {
                return false;
            }
            const keep = document.getElementById('keep');
            if (!keep) {
                return false;
            }
            keep.click();
            return true;
        };

        const refreshSession = () => {
            if (typeof resetTimer === 'function') {
                resetTimer();
            }
            if (typeof KeepSessionAlive === 'function') {
                KeepSessionAlive();
            }
            clickStaySignedIn();
        };

        const start = () => {
            if (!document.getElementById('keep') && !document.getElementById('timeOutWarningOverlay')) {
                return;
            }

            refreshSession();
            setInterval(refreshSession, 20 * 60 * 1000);
            setInterval(clickStaySignedIn, 3000);

            const overlay = document.getElementById('timeOutWarningOverlay');
            if (overlay) {
                new MutationObserver(clickStaySignedIn).observe(overlay, {
                    attributes: true,
                    attributeFilter: ['style', 'class']
                });
            }
        };

        if (document.readyState === 'loading') {
            document.addEventListener('DOMContentLoaded', start);
        } else {
            start();
        }
    })();`;

    const injectUnlock = (doc) => {
        if (!doc || !doc.documentElement || !isRealPage(doc)) {
            return false;
        }

        const href = doc.location?.href || '';
        if (doc.documentElement.getAttribute('data-vla-unlock') === href) {
            return false;
        }

        doc.documentElement.setAttribute('data-vla-unlock', href);
        doc.documentElement.removeAttribute('data-vla-unlock-init');
        return injectPageScript(doc, unlockSource, 'unlock-script');
    };

    const hookIframe = (iframe) => {
        if (!iframe || iframe.dataset.vlaUnlockHooked === '1') {
            return;
        }
        iframe.dataset.vlaUnlockHooked = '1';

        iframe.addEventListener('load', () => {
            try {
                const doc = iframe.contentDocument;
                if (doc) {
                    injectUnlock(doc);
                }
            } catch (e) {}
        });
    };

    let scanTimer = null;

    const hookQuestionIframes = () => {
        hookIframe(document.getElementById('DisplayQuestions2'));
        document.querySelectorAll('iframe').forEach((iframe) => {
            const iframeSrc = iframe.getAttribute('src') || '';
            if (/LessonQuestions\.aspx/i.test(iframeSrc)) {
                hookIframe(iframe);
            }
        });
    };

    const scheduleIframeScan = () => {
        clearTimeout(scanTimer);
        scanTimer = setTimeout(hookQuestionIframes, 100);
    };

    const initKeepAlive = () => {
        if (window !== window.top) {
            return;
        }
        injectPageScript(document, keepAliveSource, 'keepalive-script');
    };

    const path = location.pathname || '';

    if (/LessonQuestions\.aspx/i.test(path)) {
        if (document.readyState === 'loading') {
            document.addEventListener('DOMContentLoaded', () => injectUnlock(document));
        } else {
            injectUnlock(document);
        }
    }

    if (/LessonRead\.aspx/i.test(path)) {
        if (document.readyState === 'loading') {
            document.addEventListener('DOMContentLoaded', hookQuestionIframes);
        } else {
            hookQuestionIframes();
        }
        new MutationObserver(scheduleIframeScan).observe(document.documentElement, {
            childList: true,
            subtree: true
        });
    }

    if (document.readyState === 'loading') {
        document.addEventListener('DOMContentLoaded', initKeepAlive);
    } else {
        initKeepAlive();
    }
})();