// ==UserScript==
// @name         蕴瑜课堂自动答题助手
// @namespace    https://github.com/yourname
// @version      1123115811.00
// @description  修复单选题模糊匹配误判，严格基于标准化文本相等匹配
// @match        https://courses.gdut.edu.cn/mod/quiz/review.php*
// @match        https://courses.gdut.edu.cn/mod/quiz/summary.php*
// @match        https://courses.gdut.edu.cn/mod/quiz/attempt.php*
// @icon         https://courses.gdut.edu.cn/pluginfile.php/1/theme_lambda2/favicon/1780371956/favicon.ico
// @grant        GM_setValue
// @grant        GM_getValue
// @license      MIT
// ==/UserScript==

(function() {
    'use strict';

    const CONFIG = {
        AUTO_SUBMIT: true,
        SUBMIT_DELAY_SECONDS: 5,
        SHOW_CANCEL_BUTTON: true,
    };

    function log(...args) {
        console.log('[答题助手]', ...args);
    }

    function getQuizId() {
        const urlParams = new URLSearchParams(window.location.search);
        let cmid = urlParams.get('cmid');
        if (!cmid) {
            const cmidElem = document.querySelector('[data-cmid]');
            if (cmidElem) cmid = cmidElem.getAttribute('data-cmid');
        }
        return cmid || 'unknown';
    }

    // 标准化文本：去除标点符号、空格，保留汉字、字母、数字
    function normalizeForMatch(text) {
        return text.toLowerCase()
            .replace(/[，,。？?！!；;：:、""''《》【】（）()\[\]{}·…\-—]/g, '')
            .replace(/\s+/g, '');
    }

    // 严格相等匹配（标准化后）
    function isStrictMatch(text1, text2) {
        if (text1 === text2) return true;
        const norm1 = normalizeForMatch(text1);
        const norm2 = normalizeForMatch(text2);
        return norm1 === norm2;
    }

    function getQuestionNumber(queDiv) {
        const idMatch = queDiv.id.match(/-(\d+)$/);
        if (idMatch) return parseInt(idMatch[1], 10);
        const qnoSpan = queDiv.querySelector('.qno');
        if (qnoSpan) {
            const num = parseInt(qnoSpan.innerText, 10);
            if (!isNaN(num)) return num;
        }
        return null;
    }

    function getQuestionText(queDiv) {
        const qtextDiv = queDiv.querySelector('.qtext');
        return qtextDiv ? qtextDiv.innerText.trim().replace(/\s+/g, ' ') : '';
    }

    function getOptionsList(queDiv) {
        const options = [];
        const answerDiv = queDiv.querySelector('.answer');
        if (!answerDiv) return options;
        const items = answerDiv.querySelectorAll('.r0, .r1');
        for (let item of items) {
            let input = item.querySelector('input[type="checkbox"], input[type="radio"]');
            if (!input) continue;
            let textSpan = item.querySelector('.flex-fill');
            let rawText = textSpan ? textSpan.innerText.trim() : item.innerText.trim();
            const match = rawText.match(/^[A-Z]\.\s*(.*)$/);
            if (match) rawText = match[1].trim();
            options.push({
                element: input,
                text: rawText,
                value: input.value,
                container: item
            });
        }
        return options;
    }

    function detectQuestionType(queDiv) {
        if (queDiv.classList.contains('truefalse')) return 'truefalse';
        if (queDiv.classList.contains('multichoiceset')) return 'multi';
        if (queDiv.classList.contains('multichoice')) return 'single';
        const legend = queDiv.querySelector('.prompt');
        if (legend) {
            const text = legend.innerText;
            if (text.includes('选择一项或多项')) return 'multi';
            if (text.includes('选择一项')) return 'single';
        }
        return 'unknown';
    }

    // 提取正确答案（优先 correct 类，否则从 .rightanswer 解析）
    function getCorrectAnswers(queDiv) {
        const type = detectQuestionType(queDiv);
        const outcome = queDiv.querySelector('.outcome');
        if (!outcome) return [];

        const options = getOptionsList(queDiv);
        // 策略1：优先使用 correct 类（最准确）
        const correctByClass = [];
        for (let opt of options) {
            if (opt.container.classList.contains('correct')) {
                correctByClass.push(opt.text);
            }
        }
        if (correctByClass.length > 0) {
            return correctByClass;
        }

        // 策略2：从 .rightanswer 文本解析
        const rightDiv = outcome.querySelector('.rightanswer');
        if (!rightDiv) return [];
        let fullText = rightDiv.innerText.trim();
        fullText = fullText.replace(/^正确答案是[：:]\s*/, '');

        if (type === 'truefalse') {
            const match = fullText.match(/[“"]([对错])[”"]/);
            return match ? [match[1]] : [];
        }
        else if (type === 'single') {
            // 单选题：返回完整文本，不做拆分
            return [fullText];
        }
        else { // 多选题
            // 按标点拆分，并去除编号前缀
            let parts = fullText.split(/[；;，,、]+/).map(s => s.trim()).filter(s => s);
            parts = parts.map(p => p.replace(/^[A-Z]\.\s*/, ''));
            return parts;
        }
    }

    function saveAnswersFromReview() {
        const quizId = getQuizId();
        if (quizId === 'unknown') return;
        const questions = document.querySelectorAll('.que');
        if (questions.length === 0) return;

        const answersMap = {};
        for (let que of questions) {
            const qno = getQuestionNumber(que);
            const qText = getQuestionText(que);
            const type = detectQuestionType(que);
            let correctTexts = getCorrectAnswers(que);
            if (correctTexts.length === 0) continue;

            // 验证有效性：确保答案文本能够匹配到选项中的某一项
            const options = getOptionsList(que);
            let validCorrect = [];
            if (type === 'single') {
                const target = correctTexts[0];
                const matched = options.find(opt => isStrictMatch(opt.text, target));
                if (matched) {
                    validCorrect = [matched.text]; // 使用选项中的原文本
                } else {
                    log(`题目 #${qno} 答案 "${target}" 未匹配到任何选项，跳过`);
                    continue;
                }
            } else {
                for (let corr of correctTexts) {
                    const matched = options.some(opt => isStrictMatch(opt.text, corr));
                    if (matched) validCorrect.push(corr);
                    else log(`题目 #${qno} 的答案 "${corr}" 未匹配到选项，跳过该项`);
                }
                if (validCorrect.length === 0) continue;
            }

            const key = qno !== null ? `qnum_${qno}` : qText;
            answersMap[key] = {
                type: type,
                correctTexts: validCorrect,
                text: qText,
                qno: qno
            };
            log(`✅ 记录 ${type} 题 #${qno} : ${validCorrect.join(' | ')}`);
        }

        if (Object.keys(answersMap).length) {
            GM_setValue(`quiz_${quizId}`, JSON.stringify(answersMap));
            showNotification(`已记录 ${Object.keys(answersMap).length} 道题`);
        } else {
            showNotification('未提取到任何答案', 3000);
        }
    }

    // 答题页面填充（使用严格匹配）
    function applyAnswersToAttempt() {
        const quizId = getQuizId();
        if (quizId === 'unknown') return 0;
        const stored = GM_getValue(`quiz_${quizId}`);
        if (!stored) {
            showNotification('未找到答案，请先访问回顾页面', 3000);
            return 0;
        }
        let answersMap;
        try { answersMap = JSON.parse(stored); } catch(e) { return 0; }

        const questions = document.querySelectorAll('.que');
        let applied = 0;

        for (let que of questions) {
            const qno = getQuestionNumber(que);
            let key = qno !== null ? `qnum_${qno}` : null;
            let answerInfo = key ? answersMap[key] : null;
            if (!answerInfo) {
                const qText = getQuestionText(que);
                if (qText) {
                    answerInfo = Object.values(answersMap).find(info => info.text === qText);
                }
            }
            if (!answerInfo) continue;

            const correctTexts = answerInfo.correctTexts;
            const options = getOptionsList(que);
            if (options.length === 0) continue;

            const hasCheckbox = options.some(opt => opt.element.type === 'checkbox');
            const hasRadio = options.some(opt => opt.element.type === 'radio');

            if (hasRadio && correctTexts.length === 1) {
                const target = options.find(opt => isStrictMatch(opt.text, correctTexts[0]));
                if (target) {
                    target.element.checked = true;
                    applied++;
                    log(`✅ 题 #${qno} 已选中: ${target.text}`);
                } else {
                    log(`⚠️ 题 #${qno} 未找到匹配选项: ${correctTexts[0]}`);
                }
            } else if (hasCheckbox) {
                let changed = false;
                for (let opt of options) {
                    const should = correctTexts.some(corr => isStrictMatch(opt.text, corr));
                    if (should && !opt.element.checked) {
                        opt.element.checked = true;
                        changed = true;
                    } else if (!should && opt.element.checked) {
                        opt.element.checked = false;
                        changed = true;
                    }
                }
                if (changed) {
                    applied++;
                    log(`✅ 题 #${qno} 多选已勾选: ${correctTexts.join(', ')}`);
                }
            }
        }
        showNotification(`已填充 ${applied} 道题`);
        return applied;
    }

    // ========== 自动提交（保持不变）==========
    let submitTimer = null;
    let cancelDiv = null;

    function getTwoStepButton() {
        const btns = document.querySelectorAll('button, input[type="submit"]');
        for (let btn of btns) {
            const text = (btn.innerText || btn.value || '').trim();
            if (text === '全部提交并结束') return btn;
        }
        return document.querySelector('button[id*="single_button"]');
    }

    function simpleSubmit() {
        const selectors = [
            '#mod_quiz-next-nav',
            '.mod_quiz-next-nav',
            'input[value="结束试答…"]',
            'input[value="结束试答"]',
            '.submitbtns input[type="submit"]'
        ];
        for (let sel of selectors) {
            let btn = document.querySelector(sel);
            if (btn) { btn.click(); log('简单提交'); return true; }
        }
        return false;
    }

    async function twoStepSubmit() {
        const firstBtn = getTwoStepButton();
        if (!firstBtn) return false;
        firstBtn.click();
        let modalConfirm = null;
        for (let i = 0; i < 30; i++) {
            await new Promise(r => setTimeout(r, 100));
            modalConfirm = document.querySelector('.modal-footer button[data-action="save"]');
            if (modalConfirm) break;
        }
        if (modalConfirm) {
            modalConfirm.click();
            return true;
        }
        return false;
    }

    async function autoSubmit() {
        const success = await twoStepSubmit();
        if (!success) simpleSubmit();
        showNotification('已提交答案', 2000);
    }

    function showCancelBar(seconds) {
        if (!CONFIG.SHOW_CANCEL_BUTTON) return;
        if (cancelDiv) cancelDiv.remove();
        cancelDiv = document.createElement('div');
        cancelDiv.style.cssText = 'position:fixed;bottom:80px;right:20px;background:#ff9800;color:#fff;padding:10px 16px;border-radius:8px;z-index:10000;font-size:14px;cursor:pointer;box-shadow:0 2px 6px rgba(0,0,0,0.3)';
        cancelDiv.innerHTML = `⏰ 自动提交倒计时 ${seconds} 秒，点击取消`;
        cancelDiv.onclick = () => {
            if (submitTimer) clearTimeout(submitTimer);
            cancelDiv.remove();
            cancelDiv = null;
            showNotification('已取消自动提交', 1500);
        };
        document.body.appendChild(cancelDiv);
        let remaining = seconds;
        const interval = setInterval(() => {
            if (!cancelDiv) { clearInterval(interval); return; }
            remaining--;
            if (remaining <= 0) {
                clearInterval(interval);
                cancelDiv.remove();
                cancelDiv = null;
            } else {
                cancelDiv.innerHTML = `⏰ 自动提交倒计时 ${remaining} 秒，点击取消`;
            }
        }, 1000);
    }

    function scheduleAutoSubmit(filledCount) {
        if (!CONFIG.AUTO_SUBMIT) return;
        const total = document.querySelectorAll('.que').length;
        if (filledCount < total) {
            showNotification(`只填充了 ${filledCount}/${total} 道题，不自动提交`, 3000);
            return;
        }
        showCancelBar(CONFIG.SUBMIT_DELAY_SECONDS);
        submitTimer = setTimeout(autoSubmit, CONFIG.SUBMIT_DELAY_SECONDS * 1000);
    }

    function addFloatingButton() {
        const btn = document.createElement('div');
        btn.innerHTML = '📝 答题助手';
        btn.style.cssText = 'position:fixed;bottom:20px;right:20px;background:#2196f3;color:#fff;padding:8px 12px;border-radius:20px;cursor:pointer;z-index:9999;font-size:14px;box-shadow:0 2px 6px rgba(0,0,0,0.3)';
        btn.onclick = () => {
            if (location.href.includes('/review.php')) saveAnswersFromReview();
            else if (location.href.includes('/attempt.php')) {
                const cnt = applyAnswersToAttempt();
                if (cnt > 0) scheduleAutoSubmit(cnt);
            }
        };
        document.body.appendChild(btn);
    }

    function showNotification(msg, duration = 2000) {
        const div = document.createElement('div');
        div.innerText = msg;
        div.style.cssText = 'position:fixed;bottom:20px;right:20px;background:#4caf50;color:#fff;padding:10px 16px;border-radius:8px;z-index:9999;font-size:14px;box-shadow:0 2px 6px rgba(0,0,0,0.2)';
        document.body.appendChild(div);
        setTimeout(() => div.remove(), duration);
    }

    function init() {
        if (location.href.includes('/review.php')) {
            const timer = setInterval(() => {
                if (document.querySelector('.que')) {
                    clearInterval(timer);
                    saveAnswersFromReview();
                }
            }, 500);
        } else if (location.href.includes('/attempt.php')) {
            const timer = setInterval(() => {
                if (document.querySelector('.que')) {
                    clearInterval(timer);
                    const cnt = applyAnswersToAttempt();
                    if (cnt > 0) scheduleAutoSubmit(cnt);
                }
            }, 500);
        }
        addFloatingButton();
    }

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