// 格式化时间戳为日期字符串
        function formatDate(timestamp) {
            if (!timestamp) return '-';
            const date = new Date(timestamp);
            return `${date.getFullYear()}-${String(date.getMonth() + 1).padStart(2, '0')}-${String(date.getDate()).padStart(2, '0')}`;
        }

        // 渲染问卷列表
        function renderQuestionnaireList() {
            // 获取问卷列表数据
            const questionnaireList = JSON.parse(localStorage.getItem('questionnaireList') || '[]');
            const tableBody = document.querySelector('table');
            
            // 保留表头
            const tableHeader = tableBody.rows[0];
            tableBody.innerHTML = '';
            tableBody.appendChild(tableHeader);

            // 渲染每个问卷
            questionnaireList.forEach(questionnaire => {
                const tr = document.createElement('tr');
                tr.innerHTML = `
                    <td>
                        <div class="item-title">
                            <input type="checkbox" data-id="${questionnaire.id}">
                            <span>${questionnaire.title}</span>
                        </div>
                    </td>
                    <td>
                        <div class="data-row">
                            <span class="data-item">${formatDate(questionnaire.createTime)}</span>
                            <span class="data-item">${formatDate(questionnaire.publishTime)}</span>
                            <span class="data-item">${formatDate(questionnaire.data.endTime)}</span>
                            <span class="data-item">${questionnaire.status}</span>
                            <div class="data-item">
                                <button onclick="publishQuestionnaire('${questionnaire.id}')" 
                                        ${questionnaire.status !== '未发布' ? 'disabled style="opacity: 0.5; cursor: not-allowed;"' : ''}>
                                    发布问卷
                                </button>
                                <button onclick="editQuestionnaire('${questionnaire.id}')"
                                        ${questionnaire.status === '已发布' ? 'disabled style="opacity: 0.5; cursor: not-allowed;"' : ''}>
                                    编辑问卷
                                </button>
                                <button onclick="deleteQuestionnaire('${questionnaire.id}')">
                                    删除问卷
                                </button>
                                <button onclick="viewQuestionnaire('${questionnaire.id}')">
                                    查看问卷
                                </button>
                                <button onclick="fillQuestionnaire('${questionnaire.id}')"
                                        ${questionnaire.status !== '已发布' || new Date().getTime() > new Date(questionnaire.data.endTime).getTime() ? 
                                        'disabled style="opacity: 0.5; cursor: not-allowed;"' : ''}>
                                    填写问卷
                                </button>
                                <button onclick="analyzeQuestionnaire('${questionnaire.id}')"
                                        ${questionnaire.status !== '已发布' ? 'disabled style="opacity: 0.5; cursor: not-allowed;"' : ''}>
                                    分析问卷
                                </button>
                            </div>
                        </div>
                    </td>
                `;
                tableBody.appendChild(tr);
            });
        }

        // 删除问卷
        function deleteQuestionnaire(id) {
            if (!confirm('确定要删除这份问卷吗？')) return;

            let questionnaireList = JSON.parse(localStorage.getItem('questionnaireList') || '[]');
            questionnaireList = questionnaireList.filter(q => q.id !== id);
            localStorage.setItem('questionnaireList', JSON.stringify(questionnaireList));
            renderQuestionnaireList();
        }

        // 批量删除问卷
        function batchDeleteQuestionnaires() {
            const checkedBoxes = document.querySelectorAll('input[type="checkbox"]:checked');
            if (checkedBoxes.length === 0) {
                alert('请先选择要删除的问卷！');
                return;
            }

            if (!confirm(`确定要删除选中的 ${checkedBoxes.length} 份问卷吗？`)) return;

            let questionnaireList = JSON.parse(localStorage.getItem('questionnaireList') || '[]');
            const idsToDelete = Array.from(checkedBoxes).map(cb => cb.dataset.id);
            questionnaireList = questionnaireList.filter(q => !idsToDelete.includes(q.id));
            localStorage.setItem('questionnaireList', JSON.stringify(questionnaireList));
            renderQuestionnaireList();
        }

        // 全选/取消全选
        function toggleSelectAll() {
            const selectAllCheckbox = document.querySelector('.ctrl-all input[type="checkbox"]');
            const allCheckboxes = document.querySelectorAll('table input[type="checkbox"]');
            allCheckboxes.forEach(cb => cb.checked = selectAllCheckbox.checked);
        }

        // 发布问卷
        function publishQuestionnaire(id) {
            let questionnaireList = JSON.parse(localStorage.getItem('questionnaireList') || '[]');
            const index = questionnaireList.findIndex(q => q.id === id);
            if (index !== -1) {
                const now = new Date().getTime();
                questionnaireList[index].publishTime = now;
                questionnaireList[index].status = '已发布';
                questionnaireList[index].data.publishTime = now;
                questionnaireList[index].data.status = '已发布';
                localStorage.setItem('questionnaireList', JSON.stringify(questionnaireList));
                renderQuestionnaireList();
            }
        }

        // 新建问卷
        function createNewQuestionnaire() {
            window.location.href = 'createQuestion.html';
        }

        window.onload = function() {
            renderQuestionnaireList();
            document.querySelector('.ctrl-all input[type="checkbox"]')
                .addEventListener('change', toggleSelectAll);
            document.querySelector('.ctrl-all button')
                .addEventListener('click', batchDeleteQuestionnaires);
            document.querySelector('.grid-item-add')
                .addEventListener('click', createNewQuestionnaire);
        }

        // 编辑问卷
        function editQuestionnaire(id) {
            window.location.href = `editQuestion.html?id=${id}`;
        }

        // 查看问卷
        function viewQuestionnaire(id) {
            window.location.href = `viewQuestion.html?id=${id}`;
        }

        // 填写问卷
        function fillQuestionnaire(id) {
            // 检查问卷状态
            const questionnaireList = JSON.parse(localStorage.getItem('questionnaireList') || '[]');
            const questionnaire = questionnaireList.find(q => q.id === id);
            
            if (!questionnaire) {
                alert('问卷不存在！');
                return;
            }

            if (questionnaire.status !== '已发布') {
                alert('该问卷尚未发布，无法填写！');
                return;
            }

            const endTime = new Date(questionnaire.data.endTime).getTime();
            const now = new Date().getTime();
            if (now > endTime) {
                alert('该问卷已过期！');
                return;
            }

            // 跳转到填写问卷页面
            window.location.href = `fillQuestion.html?id=${id}`;
        }

        // 分析问卷
        function analyzeQuestionnaire(id) {
            const questionnaireList = JSON.parse(localStorage.getItem('questionnaireList') || '[]');
            const questionnaire = questionnaireList.find(q => q.id === id);
            
            if (!questionnaire) {
                alert('问卷不存在！');
                return;
            }

            if (questionnaire.status !== '已发布') {
                alert('未发布的问卷无法查看分析结果！');
                return;
            }
            const answers = JSON.parse(localStorage.getItem('questionnaireAnswers') || '[]');
            const hasAnswers = answers.some(a => a.questionnaireId === id);
            
            if (!hasAnswers) {
                alert('暂无人填写该问卷，无法查看分析结果！');
                return;
            }

            window.location.href = `analyzeQuestion.html?id=${id}`;
        }