{% extends "layout.html" %}

{% block page_title %}教材管理{% endblock %}

{% block content %}
<!-- 目录节点树状结构宏定义 -->
{% macro render_catalog_node(node, level) %}
<div 
    class="catalog-node relative"
    data-node-id="{{ node.id }}"
    data-node-type="{{ node.node_type }}"
    data-parent="{{ node.parent_id or '' }}"
    data-level="{{ level }}"
    data-textbook-id="{{ node.textbook_id }}">
    
    <!-- 节点卡片 -->
    <div class="flex items-start gap-4 group">
        <!-- 展开/折叠按钮区域 -->
        <div class="flex items-center gap-2 pt-4 flex-shrink-0">
            {% if node.children|length > 0 %}
            <button 
                onclick="toggleCatalogNode('{{ node.id }}'); event.stopPropagation();"
                class="w-8 h-8 rounded-full bg-white border-2 border-gray-300 hover:border-blue-500 flex items-center justify-center text-gray-600 hover:text-blue-600 transition-all expand-btn z-10 shadow-sm hover:shadow-md"
                data-expanded="{% if level == 0 %}true{% else %}false{% endif %}">
                {% if level == 0 %}
                <i class="ri-subtract-line text-sm"></i>
                {% else %}
                <i class="ri-add-line text-sm"></i>
                {% endif %}
            </button>
            {% else %}
            <div class="w-8 h-8 flex items-center justify-center">
                <div class="w-2 h-2 rounded-full bg-gray-400"></div>
            </div>
            {% endif %}
        </div>
        
        <!-- 节点内容卡片 -->
        <div class="flex-1 apple-card p-5 hover:shadow-xl transition-all duration-300 group-hover:border-blue-300 border-2 border-transparent rounded-xl {% if node.children|length > 0 %}cursor-pointer{% endif %}" {% if node.children|length > 0 %}onclick="handleCatalogCardClick(event, '{{ node.id }}')"{% endif %}>
            <div class="flex items-start justify-between">
                <div class="flex-1 min-w-0">
                    <div class="flex items-center gap-3 mb-3 flex-wrap">
                        <span class="px-3 py-1.5 rounded-lg text-xs font-bold font-mono bg-gradient-to-r {% if node.node_type == 'chapter' %}from-blue-500 to-indigo-600{% elif node.node_type == 'section' %}from-green-500 to-emerald-600{% else %}from-orange-500 to-amber-600{% endif %} text-white shadow-md">
                            {{ node.display_no or node.node_type }}
                        </span>
                        <h3 class="text-lg font-bold text-gray-800 group-hover:text-blue-600 transition-colors">
                            {{ node.title }}
                        </h3>
                    </div>
                    
                    <div class="flex items-center gap-4 text-sm text-gray-500 mt-2 flex-wrap">
                        <span class="flex items-center gap-1.5 px-2 py-1 bg-gray-50 rounded-md">
                            <i class="ri-file-list-line text-blue-500"></i>
                            <span>{{ node.node_type }}</span>
                        </span>
                        {% if node.depth %}
                        <span class="flex items-center gap-1.5 px-2 py-1 bg-gray-50 rounded-md">
                            <i class="ri-stack-line text-green-500"></i>
                            <span>层级: {{ node.depth }}</span>
                        </span>
                        {% endif %}
                        {% if node.children|length > 0 %}
                        <span class="flex items-center gap-1.5 px-2 py-1 bg-blue-50 rounded-md text-blue-600">
                            <i class="ri-node-tree"></i>
                            <span class="font-semibold">{{ node.children|length }} 个子节点</span>
                        </span>
                        {% endif %}
                    </div>
                </div>
                
                <!-- 操作按钮 -->
                <div class="flex items-center gap-2 opacity-0 group-hover:opacity-100 transition-opacity ml-4 flex-shrink-0" onclick="event.stopPropagation()">
                    {% if node.node_type == 'section' %}
                    <button 
                        onclick="showAddKpRelationModal('{{ node.id }}', '{{ node.title }}')"
                        class="px-3 py-1.5 text-xs font-semibold text-white bg-gradient-to-r from-purple-500 to-indigo-600 hover:from-purple-600 hover:to-indigo-700 rounded-lg transition-all shadow-sm hover:shadow-md flex items-center gap-1.5"
                        title="关联知识点">
                        <i class="ri-link"></i>
                        <span>关联知识点</span>
                    </button>
                    {% endif %}
                    <button 
                        onclick="showAddChildCatalogModal('{{ node.id }}', '{{ node.title }}', '{{ node.node_type }}')"
                        class="px-3 py-1.5 text-xs font-semibold text-white bg-gradient-to-r from-green-500 to-emerald-600 hover:from-green-600 hover:to-emerald-700 rounded-lg transition-all shadow-sm hover:shadow-md flex items-center gap-1.5"
                        title="添加子节点">
                        <i class="ri-add-line"></i>
                        <span>添加子节点</span>
                    </button>
                    <button 
                        onclick="showEditCatalogModal({{ node.id }})"
                        class="w-9 h-9 rounded-lg text-blue-600 bg-blue-50 hover:bg-blue-100 flex items-center justify-center transition-colors shadow-sm hover:shadow-md"
                        title="编辑">
                        <i class="ri-edit-line"></i>
                    </button>
                    <button 
                        onclick="showDeleteCatalogConfirm({{ node.id }}, '{{ node.title }}')"
                        class="w-9 h-9 rounded-lg text-red-600 bg-red-50 hover:bg-red-100 flex items-center justify-center transition-colors shadow-sm hover:shadow-md"
                        title="删除">
                        <i class="ri-delete-bin-line"></i>
                    </button>
                </div>
            </div>
        </div>
    </div>
    
    <!-- 子节点容器 -->
    {% if node.children|length > 0 %}
    <div class="children-container mt-3 ml-12 {% if level >= 1 %}hidden{% endif %}" id="children-{{ node.id }}" data-level="{{ level }}">
        {% for child in node.children %}
            {{ render_catalog_node(child, level + 1) }}
        {% endfor %}
    </div>
    {% endif %}
</div>
{% endmacro %}

<div class="flex gap-6">
    <!-- 左侧系列菜单 -->
    <div class="w-80 flex-shrink-0">
        <div class="apple-card p-6 sticky top-4 max-h-[calc(100vh-2rem)] overflow-y-auto">
            <div class="flex items-center justify-between mb-6 pb-3 border-b border-gray-200">
                <h2 class="text-lg font-bold text-gray-800">教材系列</h2>
                <button 
                    onclick="showAddSeriesModal()"
                    class="btn-apple bg-gradient-to-r from-blue-600 to-indigo-600 text-white hover:from-blue-700 hover:to-indigo-700 text-xs py-1.5 px-3 rounded-lg shadow-sm flex items-center gap-1">
                    <i class="ri-add-circle-line"></i>
                    <span>添加</span>
                </button>
            </div>
            
            <!-- 搜索框 -->
            <div class="mb-4">
                <div class="relative">
                    <i class="ri-search-line absolute left-2.5 top-1/2 transform -translate-y-1/2 text-gray-400 text-xs"></i>
                    <input 
                        type="text" 
                        id="seriesSearchInput"
                        placeholder="搜索系列..."
                        class="w-full pl-7 pr-3 py-2 text-xs border border-gray-300 rounded-lg focus:ring-2 focus:ring-blue-500 focus:border-transparent transition-all"
                        oninput="filterSeriesList()">
                </div>
            </div>
            
            <!-- 系列列表 -->
            <nav class="space-y-1" id="seriesListNav">
                {% for series in series_list %}
                <div class="series-item mb-2" data-series-id="{{ series.id }}" data-series-name="{{ series.name }}" data-series-active="{{ series.is_active }}">
                    <div class="flex items-center gap-2 group">
                        <div class="flex-1 flex items-center gap-2">
                            <a href="javascript:void(0)" 
                               onclick="switchSeries({{ series.id }})"
                               class="flex-1 block px-4 py-2.5 rounded-xl hover:bg-gradient-to-r hover:from-slate-50 hover:to-blue-50 transition-all border-l-4 border-transparent hover:border-slate-500 series-link {% if loop.first %}bg-gradient-to-r from-slate-50 to-blue-50 border-slate-500{% endif %}">
                                <span class="text-sm font-semibold text-gray-800 group-hover:text-slate-600 transition-colors">{{ series.name }}</span>
                            </a>
                            <!-- 激活状态开关 -->
                            <label class="relative inline-flex items-center cursor-pointer flex-shrink-0" onclick="event.stopPropagation(); event.preventDefault(); toggleSeriesActiveDirect({{ series.id }}, this);">
                                <input type="checkbox" class="sr-only peer" {% if series.is_active == 1 %}checked{% endif %} onclick="event.stopPropagation();">
                                <div class="w-9 h-5 bg-gray-300 peer-focus:outline-none peer-focus:ring-2 peer-focus:ring-blue-500 rounded-full peer peer-checked:after:translate-x-full peer-checked:after:border-white after:content-[''] after:absolute after:top-[2px] after:left-[2px] after:bg-white after:border-gray-300 after:border after:rounded-full after:h-4 after:w-4 after:transition-all peer-checked:bg-blue-600"></div>
                            </label>
                        </div>
                        <button 
                            onclick="event.stopPropagation(); event.preventDefault(); showEditSeriesModal({{ series.id }});"
                            class="opacity-0 group-hover:opacity-100 transition-opacity p-1.5 hover:bg-gray-100 rounded text-gray-500 hover:text-blue-600"
                            title="编辑">
                            <i class="ri-edit-line text-sm"></i>
                        </button>
                    </div>
                </div>
                {% endfor %}
            </nav>
        </div>
    </div>
    
    <!-- 右侧内容区域 -->
    <div class="flex-1 space-y-6">
        <!-- 教材列表（当前系列下的教材） -->
        <div id="textbookListContainer" class="grid grid-cols-2 sm:grid-cols-3 md:grid-cols-4 lg:grid-cols-5 xl:grid-cols-6 gap-4">
            <!-- 教材卡片将通过JavaScript动态加载 -->
        </div>

        <!-- 目录树结构（选中教材后显示） -->
        <div id="catalogTreeContainer" class="hidden">
            <div class="flex items-center justify-between mb-4">
                <h2 class="text-xl font-bold text-gray-800" id="currentTextbookTitle"></h2>
                <button 
                    onclick="showAddCatalogModal()"
                    class="btn-apple bg-gradient-to-r from-blue-600 to-indigo-600 text-white hover:from-blue-700 hover:to-indigo-700 px-4 py-2 rounded-lg shadow-sm flex items-center gap-2">
                    <i class="ri-add-circle-line"></i>
                    <span>添加目录节点</span>
                </button>
            </div>
            
            <div class="space-y-3" id="catalogTree">
                <!-- 目录树将通过JavaScript动态加载 -->
            </div>
        </div>
    </div>
</div>

<!-- 添加/编辑教材系列模态框 -->
<div id="seriesModal" class="hidden fixed inset-0 bg-black bg-opacity-50 z-50 flex items-center justify-center">
    <div class="bg-white rounded-2xl shadow-2xl max-w-md w-full mx-4">
        <div class="p-6 border-b border-gray-200">
            <h2 id="seriesModalTitle" class="text-xl font-bold text-gray-800">添加教材系列</h2>
        </div>
        <form id="seriesForm" class="p-6 space-y-4">
            <input type="hidden" id="seriesId" name="id">
            <div>
                <label class="block text-sm font-semibold text-gray-700 mb-2">系列名称 *</label>
                <input type="text" id="seriesName" name="name" required
                    class="w-full px-4 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-blue-500 focus:border-transparent">
            </div>
            <div>
                <label class="block text-sm font-semibold text-gray-700 mb-2">标识符</label>
                <input type="text" id="seriesSlug" name="slug"
                    class="w-full px-4 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-blue-500 focus:border-transparent">
            </div>
            <div>
                <label class="flex items-center justify-between cursor-pointer">
                    <span class="text-sm font-semibold text-gray-700">激活状态</span>
                    <label class="relative inline-flex items-center cursor-pointer">
                        <input type="checkbox" id="seriesIsActive" class="sr-only peer" checked>
                        <div class="w-11 h-6 bg-gray-300 peer-focus:outline-none peer-focus:ring-2 peer-focus:ring-blue-500 rounded-full peer peer-checked:after:translate-x-full peer-checked:after:border-white after:content-[''] after:absolute after:top-[2px] after:left-[2px] after:bg-white after:border-gray-300 after:border after:rounded-full after:h-5 after:w-5 after:transition-all peer-checked:bg-blue-600"></div>
                    </label>
                </label>
                <p class="text-xs text-gray-500 mt-1">激活的系列将在系统中可用</p>
            </div>
            <div class="flex gap-3 pt-4">
                <button type="button" onclick="closeSeriesModal()" class="flex-1 px-4 py-2 border border-gray-300 rounded-lg hover:bg-gray-50">取消</button>
                <button type="submit" class="flex-1 px-4 py-2 bg-blue-600 text-white rounded-lg hover:bg-blue-700">保存</button>
            </div>
        </form>
    </div>
</div>

<!-- 添加/编辑教材模态框 -->
<div id="textbookModal" class="hidden fixed inset-0 bg-black bg-opacity-50 z-50 flex items-center justify-center">
    <div class="bg-white rounded-2xl shadow-2xl max-w-md w-full mx-4">
        <div class="p-6 border-b border-gray-200">
            <h2 id="textbookModalTitle" class="text-xl font-bold text-gray-800">添加教材</h2>
        </div>
        <form id="textbookForm" class="p-6 space-y-4">
            <input type="hidden" id="textbookId" name="id">
            <div>
                <label class="block text-sm font-semibold text-gray-700 mb-2">教材名称 *</label>
                <input type="text" id="textbookTitle" name="official_title" required
                    class="w-full px-4 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-blue-500 focus:border-transparent">
            </div>
            <div class="grid grid-cols-2 gap-4">
                <div>
                    <label class="block text-sm font-semibold text-gray-700 mb-2">学段</label>
                    <select id="textbookStage" name="stage" class="w-full px-4 py-2 border border-gray-300 rounded-lg">
                        <option value="">请选择</option>
                        <option value="primary">小学</option>
                        <option value="junior">初中</option>
                        <option value="senior">高中</option>
                    </select>
                </div>
                <div>
                    <label class="block text-sm font-semibold text-gray-700 mb-2">年级</label>
                    <input type="text" id="textbookGrade" name="grade"
                        class="w-full px-4 py-2 border border-gray-300 rounded-lg">
                </div>
            </div>
            <div>
                <label class="block text-sm font-semibold text-gray-700 mb-2">学期</label>
                <select id="textbookSemester" name="semester" class="w-full px-4 py-2 border border-gray-300 rounded-lg">
                    <option value="">请选择</option>
                    <option value="1">上学期</option>
                    <option value="2">下学期</option>
                </select>
            </div>
            <div class="flex gap-3 pt-4">
                <button type="button" onclick="closeTextbookModal()" class="flex-1 px-4 py-2 border border-gray-300 rounded-lg hover:bg-gray-50">取消</button>
                <button type="submit" class="flex-1 px-4 py-2 bg-blue-600 text-white rounded-lg hover:bg-blue-700">保存</button>
            </div>
        </form>
    </div>
</div>

<!-- 添加/编辑目录节点模态框 -->
<div id="catalogModal" class="hidden fixed inset-0 bg-black bg-opacity-50 z-50 flex items-center justify-center">
    <div class="bg-white rounded-2xl shadow-2xl max-w-md w-full mx-4">
        <div class="p-6 border-b border-gray-200">
            <h2 id="catalogModalTitle" class="text-xl font-bold text-gray-800">添加目录节点</h2>
        </div>
        <form id="catalogForm" class="p-6 space-y-4">
            <input type="hidden" id="catalogId" name="id">
            <input type="hidden" id="catalogTextbookId" name="textbook_id">
            <input type="hidden" id="catalogParentId" name="parent_id">
            <div>
                <label class="block text-sm font-semibold text-gray-700 mb-2">节点类型 *</label>
                <select id="catalogNodeType" name="node_type" required class="w-full px-4 py-2 border border-gray-300 rounded-lg">
                    <option value="chapter">章节</option>
                    <option value="section">小节</option>
                    <option value="subsection">子小节</option>
                </select>
            </div>
            <div>
                <label class="block text-sm font-semibold text-gray-700 mb-2">标题 *</label>
                <input type="text" id="catalogTitle" name="title" required
                    class="w-full px-4 py-2 border border-gray-300 rounded-lg focus:ring-2 focus:ring-blue-500 focus:border-transparent">
            </div>
            <div>
                <label class="block text-sm font-semibold text-gray-700 mb-2">编号</label>
                <input type="text" id="catalogDisplayNo" name="display_no"
                    class="w-full px-4 py-2 border border-gray-300 rounded-lg">
            </div>
            <div class="flex gap-3 pt-4">
                <button type="button" onclick="closeCatalogModal()" class="flex-1 px-4 py-2 border border-gray-300 rounded-lg hover:bg-gray-50">取消</button>
                <button type="submit" class="flex-1 px-4 py-2 bg-blue-600 text-white rounded-lg hover:bg-blue-700">保存</button>
            </div>
        </form>
    </div>
</div>

<!-- 关联知识点模态框 -->
<div id="kpRelationModal" class="hidden fixed inset-0 bg-black bg-opacity-50 z-50 flex items-center justify-center">
    <div class="bg-white rounded-2xl shadow-2xl max-w-2xl w-full mx-4 max-h-[90vh] overflow-y-auto">
        <div class="p-6 border-b border-gray-200">
            <h2 id="kpRelationModalTitle" class="text-xl font-bold text-gray-800">关联知识点</h2>
        </div>
        <div class="p-6">
            <div class="mb-4">
                <label class="block text-sm font-semibold text-gray-700 mb-2">选择知识点</label>
                <select id="kpCodeSelect" class="w-full px-4 py-2 border border-gray-300 rounded-lg">
                    <option value="">请选择知识点</option>
                    {% for kp in kp_options %}
                    <option value="{{ kp.kp_code }}">{{ kp.kp_code }} - {{ kp.name }}</option>
                    {% endfor %}
                </select>
            </div>
            <button onclick="addKpRelation()" class="w-full px-4 py-2 bg-blue-600 text-white rounded-lg hover:bg-blue-700 mb-4">
                添加关联
            </button>
            <div id="kpRelationList" class="space-y-2">
                <!-- 关联列表将通过JavaScript动态加载 -->
            </div>
        </div>
        <div class="p-6 border-t border-gray-200">
            <button onclick="closeKpRelationModal()" class="w-full px-4 py-2 border border-gray-300 rounded-lg hover:bg-gray-50">关闭</button>
        </div>
    </div>
</div>

<script>
// 当前选中的系列ID和教材ID
let currentSeriesId = null;
let currentTextbookId = null;
let currentCatalogChapterId = null;

// 所有系列数据
const allSeries = {{ series_list|tojson|safe }};

// 初始化：加载第一个系列
document.addEventListener('DOMContentLoaded', function() {
    const firstSeriesItem = document.querySelector('.series-item');
    if (firstSeriesItem) {
        const firstSeriesId = parseInt(firstSeriesItem.getAttribute('data-series-id'));
        switchSeries(firstSeriesId);
    }
});

// 筛选系列列表
function filterSeriesList() {
    const searchInput = document.getElementById('seriesSearchInput');
    const searchTerm = (searchInput.value || '').toLowerCase().trim();
    const seriesItems = document.querySelectorAll('.series-item');
    
    let visibleCount = 0;
    seriesItems.forEach(item => {
        const seriesName = item.getAttribute('data-series-name').toLowerCase();
        const matchesSearch = !searchTerm || seriesName.includes(searchTerm);
        
        if (matchesSearch) {
            item.style.display = '';
            visibleCount++;
        } else {
            item.style.display = 'none';
        }
    });
}

// 切换教材系列
async function switchSeries(seriesId) {
    // 确保seriesId是数字类型
    seriesId = parseInt(seriesId);
    if (!seriesId || isNaN(seriesId)) {
        console.error('Invalid seriesId:', seriesId);
        return;
    }
    
    currentSeriesId = seriesId;
    
    // 更新左侧菜单选中状态
    document.querySelectorAll('.series-link').forEach(link => {
        link.classList.remove('bg-gradient-to-r', 'from-slate-50', 'to-blue-50', 'border-slate-500');
    });
    
    const selectedLink = document.querySelector(`.series-item[data-series-id="${seriesId}"] .series-link`);
    if (selectedLink) {
        selectedLink.classList.add('bg-gradient-to-r', 'from-slate-50', 'to-blue-50', 'border-slate-500');
    }
    
    // 获取容器
    const container = document.getElementById('textbookListContainer');
    if (!container) {
        console.error('textbookListContainer not found');
        return;
    }
    
    // 显示教材列表容器，隐藏目录树
    container.classList.remove('hidden');
    document.getElementById('catalogTreeContainer').classList.add('hidden');
    
    // 显示加载状态
    container.innerHTML = '<div class="col-span-full text-center py-12"><i class="ri-loader-4-line animate-spin text-3xl text-blue-500"></i><p class="mt-3 text-gray-500">加载中...</p></div>';
    
    // 加载该系列下的教材
    try {
        const response = await fetch(`/api/textbook/list/${seriesId}`);
        
        if (!response.ok) {
            throw new Error(`HTTP error! status: ${response.status}`);
        }
        
        const result = await response.json();
        
        if (result.success) {
            // 确保data是数组
            const textbooks = Array.isArray(result.data) ? result.data : [];
            
            if (textbooks.length === 0) {
                container.innerHTML = '<div class="col-span-full text-center py-12"><i class="ri-book-open-line text-4xl text-gray-300 mb-3"></i><p class="text-gray-500">暂无教材</p><p class="text-xs text-gray-400 mt-2">该系列下还没有添加教材</p></div>';
            } else {
                renderTextbookList(textbooks);
            }
        } else {
            console.error('API error:', result.error);
            container.innerHTML = '<div class="col-span-full text-center py-12"><i class="ri-error-warning-line text-4xl text-red-300 mb-3"></i><p class="text-gray-500">加载失败：' + (result.error || '未知错误') + '</p><button onclick="switchSeries(' + seriesId + ')" class="mt-4 px-4 py-2 bg-blue-500 text-white rounded-lg hover:bg-blue-600">重试</button></div>';
        }
    } catch (error) {
        console.error('Error loading textbooks:', error);
        container.innerHTML = '<div class="col-span-full text-center py-12"><i class="ri-error-warning-line text-4xl text-red-300 mb-3"></i><p class="text-gray-500">加载教材列表失败</p><p class="text-xs text-gray-400 mt-2">' + error.message + '</p><button onclick="switchSeries(' + seriesId + ')" class="mt-4 px-4 py-2 bg-blue-500 text-white rounded-lg hover:bg-blue-600">重试</button></div>';
    }
}

// 直接在列表中切换系列激活状态
async function toggleSeriesActiveDirect(seriesId, labelElement) {
    const checkbox = labelElement.querySelector('input[type="checkbox"]');
    if (!checkbox) return;
    
    // 立即切换开关状态（乐观更新）
    const newState = !checkbox.checked;
    checkbox.checked = newState;
    
    // 禁用开关，防止重复点击
    checkbox.disabled = true;
    
    try {
        const response = await fetch(`/api/textbook/series/toggle_active/${seriesId}`, {
            method: 'POST',
            headers: {'Content-Type': 'application/json'}
        });
        
        const result = await response.json();
        
        if (result.success) {
            // 更新系列项的data-active属性
            const seriesItem = document.querySelector(`.series-item[data-series-id="${seriesId}"]`);
            if (seriesItem) {
                seriesItem.setAttribute('data-series-active', result.is_active);
            }
            
            // 更新allSeries数据
            const series = allSeries.find(s => s.id === seriesId);
            if (series) {
                series.is_active = result.is_active;
            }
            
            // 确保checkbox状态与服务器一致
            checkbox.checked = result.is_active === 1;
            
            // 如果当前选中的系列，刷新教材列表
            if (currentSeriesId === seriesId) {
                switchSeries(seriesId);
            }
        } else {
            // 恢复开关状态
            checkbox.checked = !newState;
            if (window.customAlert) {
                window.customAlert('操作失败: ' + result.error);
            } else {
                alert('操作失败: ' + result.error);
            }
        }
    } catch (error) {
        console.error('Error:', error);
        // 恢复开关状态
        checkbox.checked = !newState;
        if (window.customAlert) {
            window.customAlert('操作失败: ' + error.message);
        } else {
            alert('操作失败: ' + error.message);
        }
    } finally {
        checkbox.disabled = false;
    }
}


// 渲染教材列表
function renderTextbookList(textbooks) {
    const container = document.getElementById('textbookListContainer');
    container.innerHTML = '';
    
    textbooks.forEach(textbook => {
        const card = document.createElement('div');
        card.className = 'group relative apple-card overflow-hidden cursor-pointer hover:shadow-2xl transition-all duration-300 hover:-translate-y-1';
        card.onclick = () => loadTextbookCatalog(textbook.id, textbook.official_title);
        
        // 生成封面占位图的渐变背景色（根据教材ID生成不同颜色）
        const colors = [
            'from-blue-500 to-indigo-600',
            'from-green-500 to-emerald-600',
            'from-purple-500 to-violet-600',
            'from-pink-500 to-rose-600',
            'from-orange-500 to-amber-600',
            'from-cyan-500 to-blue-600'
        ];
        const colorIndex = (textbook.id || 0) % colors.length;
        const gradientColor = colors[colorIndex];
        
        card.innerHTML = `
            <!-- 封面占位图 -->
            <div class="relative w-full aspect-[3/4] bg-gradient-to-br ${gradientColor} overflow-hidden">
                <div class="absolute inset-0 flex items-center justify-center">
                    <div class="text-center text-white/90">
                        <i class="ri-book-open-line text-6xl mb-2 opacity-80"></i>
                        <div class="text-xs font-semibold opacity-70">教材封面</div>
                    </div>
                </div>
                <!-- 封面装饰线条 -->
                <div class="absolute top-0 left-0 right-0 h-1 bg-white/20"></div>
                <div class="absolute bottom-0 left-0 right-0 h-1 bg-black/10"></div>
                <!-- 操作按钮（悬停显示） -->
                <div class="absolute top-2 right-2 flex gap-2 opacity-0 group-hover:opacity-100 transition-opacity" onclick="event.stopPropagation()">
                    <button onclick="showEditTextbookModal(${textbook.id})" class="w-8 h-8 rounded-full bg-white/90 backdrop-blur-sm text-blue-600 hover:bg-white hover:scale-110 transition-all shadow-lg flex items-center justify-center">
                        <i class="ri-edit-line text-sm"></i>
                    </button>
                    <button onclick="showDeleteTextbookConfirm(${textbook.id}, '${textbook.official_title}')" class="w-8 h-8 rounded-full bg-white/90 backdrop-blur-sm text-red-600 hover:bg-white hover:scale-110 transition-all shadow-lg flex items-center justify-center">
                        <i class="ri-delete-bin-line text-sm"></i>
                    </button>
                </div>
            </div>
            
            <!-- 教材信息 -->
            <div class="p-4 bg-white">
                <h3 class="text-base font-bold text-gray-800 mb-2 line-clamp-2 leading-tight">${textbook.official_title || '未命名教材'}</h3>
                <div class="flex items-center gap-2 text-xs text-gray-500">
                    ${textbook.grade ? `<span class="px-2 py-0.5 bg-gray-100 rounded">${textbook.grade}年级</span>` : ''}
                    ${textbook.semester ? `<span class="px-2 py-0.5 bg-gray-100 rounded">${textbook.semester === 1 ? '上学期' : '下学期'}</span>` : ''}
                </div>
            </div>
        `;
        container.appendChild(card);
    });
    
    // 添加"添加教材"卡片
    const addCard = document.createElement('div');
    addCard.className = 'apple-card overflow-hidden cursor-pointer hover:shadow-xl transition-all border-2 border-dashed border-gray-300 hover:border-blue-400';
    addCard.onclick = () => showAddTextbookModal();
    addCard.innerHTML = `
        <div class="w-full aspect-[3/4] flex flex-col items-center justify-center text-gray-400 hover:text-blue-500 transition-colors">
            <div class="mb-3">
                <i class="ri-add-circle-line text-5xl"></i>
            </div>
            <div class="text-sm font-medium">添加教材</div>
        </div>
    `;
    container.appendChild(addCard);
}

// 加载教材目录树
async function loadTextbookCatalog(textbookId, textbookTitle) {
    currentTextbookId = textbookId;
    const titleElement = document.getElementById('currentTextbookTitle');
    const catalogContainer = document.getElementById('catalogTreeContainer');
    const textbookContainer = document.getElementById('textbookListContainer');
    
    if (titleElement) {
        titleElement.textContent = textbookTitle;
    }
    
    // 显示目录树，隐藏教材列表
    if (catalogContainer) {
        catalogContainer.classList.remove('hidden');
    }
    if (textbookContainer) {
        textbookContainer.classList.add('hidden');
    }
    
    try {
        const response = await fetch(`/api/textbook/catalog/tree/${textbookId}`);
        const result = await response.json();
        
        if (result.success) {
            renderCatalogTree(result.data);
        } else {
            console.error('Failed to load catalog tree:', result.error);
            if (window.customAlert) {
                window.customAlert('加载目录树失败: ' + (result.error || '未知错误'));
            } else {
                alert('加载目录树失败: ' + (result.error || '未知错误'));
            }
        }
    } catch (error) {
        console.error('Error loading catalog tree:', error);
        if (window.customAlert) {
            window.customAlert('加载目录树失败: ' + error.message);
        } else {
            alert('加载目录树失败: ' + error.message);
        }
    }
}

// 渲染目录树
function renderCatalogTree(nodes) {
    const container = document.getElementById('catalogTree');
    container.innerHTML = '';
    
    // 这里需要使用Jinja2宏来渲染，但由于是动态加载，我们需要用JavaScript递归渲染
    // 为了简化，我们先用简单的HTML结构
    nodes.forEach(node => {
        container.appendChild(createCatalogNodeElement(node, 0));
    });
}

// 创建目录节点元素（简化版，实际应该使用服务端渲染）
function createCatalogNodeElement(node, level) {
    const div = document.createElement('div');
    div.className = `catalog-node relative mb-3`;
    div.setAttribute('data-node-id', node.id);
    div.setAttribute('data-level', level);
    
    const hasChildren = node.children && node.children.length > 0;
    const colorClass = node.node_type === 'chapter' ? 'from-blue-500 to-indigo-600' : 
                      node.node_type === 'section' ? 'from-green-500 to-emerald-600' : 
                      'from-orange-500 to-amber-600';
    
    div.innerHTML = `
        <div class="flex items-start gap-4 group">
            <div class="flex items-center gap-2 pt-4 flex-shrink-0">
                ${hasChildren ? `
                <button onclick="toggleCatalogNode('${node.id}'); event.stopPropagation();" 
                    class="w-8 h-8 rounded-full bg-white border-2 border-gray-300 hover:border-blue-500 flex items-center justify-center text-gray-600 hover:text-blue-600 transition-all expand-btn z-10 shadow-sm hover:shadow-md"
                    data-expanded="${level === 0 ? 'true' : 'false'}">
                    <i class="ri-${level === 0 ? 'subtract' : 'add'}-line text-sm"></i>
                </button>
                ` : `
                <div class="w-8 h-8 flex items-center justify-center">
                    <div class="w-2 h-2 rounded-full bg-gray-400"></div>
                </div>
                `}
            </div>
            <div class="flex-1 apple-card p-5 hover:shadow-xl transition-all duration-300 group-hover:border-blue-300 border-2 border-transparent rounded-xl ${hasChildren ? 'cursor-pointer' : ''}" 
                 ${hasChildren ? `onclick="handleCatalogCardClick(event, '${node.id}')"` : ''}>
                <div class="flex items-start justify-between">
                    <div class="flex-1 min-w-0">
                        <div class="flex items-center gap-3 mb-3 flex-wrap">
                            <span class="px-3 py-1.5 rounded-lg text-xs font-bold font-mono bg-gradient-to-r ${colorClass} text-white shadow-md">
                                ${node.display_no || node.node_type}
                            </span>
                            <h3 class="text-lg font-bold text-gray-800 group-hover:text-blue-600 transition-colors">
                                ${node.title}
                            </h3>
                        </div>
                        <div class="flex items-center gap-4 text-sm text-gray-500 mt-2 flex-wrap">
                            <span class="flex items-center gap-1.5 px-2 py-1 bg-gray-50 rounded-md">
                                <i class="ri-file-list-line text-blue-500"></i>
                                <span>${node.node_type}</span>
                            </span>
                            ${hasChildren ? `
                            <span class="flex items-center gap-1.5 px-2 py-1 bg-blue-50 rounded-md text-blue-600">
                                <i class="ri-node-tree"></i>
                                <span class="font-semibold">${node.children.length} 个子节点</span>
                            </span>
                            ` : ''}
                        </div>
                    </div>
                    <div class="flex items-center gap-2 opacity-0 group-hover:opacity-100 transition-opacity ml-4 flex-shrink-0" onclick="event.stopPropagation()">
                        ${node.node_type === 'section' ? `
                        <button onclick="showAddKpRelationModal('${node.id}', '${node.title}')" 
                            class="px-3 py-1.5 text-xs font-semibold text-white bg-gradient-to-r from-purple-500 to-indigo-600 hover:from-purple-600 hover:to-indigo-700 rounded-lg transition-all shadow-sm hover:shadow-md flex items-center gap-1.5">
                            <i class="ri-link"></i>
                            <span>关联知识点</span>
                        </button>
                        ` : ''}
                        <button onclick="showAddChildCatalogModal('${node.id}', '${node.title}', '${node.node_type}')" 
                            class="px-3 py-1.5 text-xs font-semibold text-white bg-gradient-to-r from-green-500 to-emerald-600 hover:from-green-600 hover:to-emerald-700 rounded-lg transition-all shadow-sm hover:shadow-md flex items-center gap-1.5">
                            <i class="ri-add-line"></i>
                            <span>添加子节点</span>
                        </button>
                        <button onclick="showEditCatalogModal(${node.id})" 
                            class="w-9 h-9 rounded-lg text-blue-600 bg-blue-50 hover:bg-blue-100 flex items-center justify-center transition-colors shadow-sm hover:shadow-md">
                            <i class="ri-edit-line"></i>
                        </button>
                        <button onclick="showDeleteCatalogConfirm(${node.id}, '${node.title}')" 
                            class="w-9 h-9 rounded-lg text-red-600 bg-red-50 hover:bg-red-100 flex items-center justify-center transition-colors shadow-sm hover:shadow-md">
                            <i class="ri-delete-bin-line"></i>
                        </button>
                    </div>
                </div>
            </div>
        </div>
        ${hasChildren ? `
        <div class="children-container mt-3 ml-12 ${level >= 1 ? 'hidden' : ''}" id="children-${node.id}" data-level="${level}">
            ${node.children.map(child => createCatalogNodeElement(child, level + 1).outerHTML).join('')}
        </div>
        ` : ''}
        ${node.node_type === 'section' ? `
        <div class="knowledge-points-container mt-3 ml-12" id="kp-${node.id}">
            <div class="flex items-center gap-2 mb-2">
                <i class="ri-loader-4-line animate-spin text-gray-400 text-sm"></i>
                <span class="text-xs text-gray-500">加载知识点...</span>
            </div>
        </div>
        ` : ''}
    `;
    
    // 如果是section节点，异步加载关联的知识点
    if (node.node_type === 'section') {
        setTimeout(() => loadKnowledgePointsForSection(node.id), 100);
    }
    
    return div;
}

// 切换目录节点展开/折叠
function toggleCatalogNode(nodeId) {
    const childrenContainer = document.getElementById(`children-${nodeId}`);
    if (!childrenContainer) return;
    
    const kpNode = childrenContainer.closest('.catalog-node');
    if (!kpNode) return;
    
    const expandBtn = kpNode.querySelector('.expand-btn');
    if (!expandBtn) return;
    
    const isExpanded = expandBtn.getAttribute('data-expanded') === 'true';
    
    if (isExpanded) {
        childrenContainer.classList.add('hidden');
        expandBtn.setAttribute('data-expanded', 'false');
        const icon = expandBtn.querySelector('i');
        if (icon) {
            icon.className = 'ri-add-line text-sm';
        }
    } else {
        childrenContainer.classList.remove('hidden');
        expandBtn.setAttribute('data-expanded', 'true');
        const icon = expandBtn.querySelector('i');
        if (icon) {
            icon.className = 'ri-subtract-line text-sm';
        }
    }
}

// 处理卡片点击
function handleCatalogCardClick(event, nodeId) {
    if (event.target.closest('button') || event.target.closest('a')) {
        return;
    }
    toggleCatalogNode(nodeId);
}

// 加载section关联的知识点
async function loadKnowledgePointsForSection(sectionId) {
    const container = document.getElementById(`kp-${sectionId}`);
    if (!container) return;
    
    try {
        const response = await fetch(`/api/textbook/relation/list/${sectionId}`);
        const result = await response.json();
        
        if (result.success && result.data && result.data.length > 0) {
            // 去重：按kp_code去重，保留第一个
            const uniqueRelations = [];
            const seenKpCodes = new Set();
            
            result.data.forEach(relation => {
                if (!seenKpCodes.has(relation.kp_code)) {
                    seenKpCodes.add(relation.kp_code);
                    uniqueRelations.push(relation);
                }
            });
            
            container.innerHTML = `
                <div class="mb-2">
                    <span class="text-xs font-semibold text-purple-600 flex items-center gap-1">
                        <i class="ri-link"></i>
                        <span>关联知识点 (${uniqueRelations.length})</span>
                    </span>
                </div>
                <div class="flex flex-wrap gap-2">
                    ${uniqueRelations.map(relation => `
                        <div class="group relative px-3 py-2 bg-gradient-to-r from-purple-50 to-indigo-50 border border-purple-200 rounded-lg hover:shadow-md transition-all">
                            <div class="flex items-center gap-2">
                                <span class="text-xs font-mono font-bold text-purple-600">${relation.kp_code || ''}</span>
                                <span class="text-sm text-gray-700">${relation.kp_name || '未知知识点'}</span>
                                <button onclick="removeKpRelationByCode('${relation.kp_code}', ${sectionId})" 
                                    class="opacity-0 group-hover:opacity-100 ml-1 w-5 h-5 rounded-full bg-red-100 hover:bg-red-200 text-red-600 flex items-center justify-center transition-all"
                                    title="取消关联">
                                    <i class="ri-close-line text-xs"></i>
                                </button>
                            </div>
                        </div>
                    `).join('')}
                </div>
            `;
        } else {
            container.innerHTML = `
                <div class="text-xs text-gray-400 italic">
                    <i class="ri-information-line"></i>
                    <span>暂无关联知识点</span>
                </div>
            `;
        }
    } catch (error) {
        console.error('Error loading knowledge points:', error);
        container.innerHTML = `
            <div class="text-xs text-red-400">
                <i class="ri-error-warning-line"></i>
                <span>加载知识点失败</span>
            </div>
        `;
    }
}

// 移除知识点关联（通过relationId）
async function removeKpRelation(relationId, sectionId) {
    if (!confirm('确定要取消这个知识点关联吗？')) {
        return;
    }
    
    try {
        const response = await fetch(`/api/textbook/relation/delete/${relationId}`, {
            method: 'POST',
            headers: {'Content-Type': 'application/json'}
        });
        
        const result = await response.json();
        
        if (result.success) {
            // 重新加载知识点列表
            loadKnowledgePointsForSection(sectionId);
            
            if (window.customAlert) {
                window.customAlert('已取消关联');
            } else {
                alert('已取消关联');
            }
        } else {
            if (window.customAlert) {
                window.customAlert('操作失败: ' + result.error);
            } else {
                alert('操作失败: ' + result.error);
            }
        }
    } catch (error) {
        console.error('Error:', error);
        if (window.customAlert) {
            window.customAlert('操作失败: ' + error.message);
        } else {
            alert('操作失败: ' + error.message);
        }
    }
}

// 移除知识点关联（通过kp_code，删除所有重复的关联）
async function removeKpRelationByCode(kpCode, sectionId) {
    if (!confirm('确定要取消这个知识点关联吗？')) {
        return;
    }
    
    try {
        // 先获取所有该知识点的关联
        const listResponse = await fetch(`/api/textbook/relation/list/${sectionId}`);
        const listResult = await listResponse.json();
        
        if (!listResult.success || !listResult.data) {
            throw new Error('获取关联列表失败');
        }
        
        // 找到所有匹配的关联ID
        const relationIds = listResult.data
            .filter(rel => rel.kp_code === kpCode)
            .map(rel => rel.id);
        
        if (relationIds.length === 0) {
            if (window.customAlert) {
                window.customAlert('未找到关联');
            } else {
                alert('未找到关联');
            }
            return;
        }
        
        // 删除所有重复的关联
        const deletePromises = relationIds.map(id => 
            fetch(`/api/textbook/relation/delete/${id}`, {
                method: 'POST',
                headers: {'Content-Type': 'application/json'}
            })
        );
        
        await Promise.all(deletePromises);
        
        // 重新加载知识点列表
        loadKnowledgePointsForSection(sectionId);
        
        // 如果模态框打开，也刷新模态框中的列表
        if (currentKpRelationSectionId === sectionId) {
            await loadKpRelations(sectionId);
        }
        
        if (window.customAlert) {
            window.customAlert('已取消关联');
        } else {
            alert('已取消关联');
        }
    } catch (error) {
        console.error('Error:', error);
        if (window.customAlert) {
            window.customAlert('操作失败: ' + error.message);
        } else {
            alert('操作失败: ' + error.message);
        }
    }
}

// ==================== 教材系列 CRUD ====================
function showAddSeriesModal() {
    document.getElementById('seriesModalTitle').textContent = '添加教材系列';
    document.getElementById('seriesForm').reset();
    document.getElementById('seriesId').value = '';
    document.getElementById('seriesIsActive').checked = true; // 默认激活
    document.getElementById('seriesModal').classList.remove('hidden');
}

async function showEditSeriesModal(seriesId) {
    try {
        const response = await fetch(`/api/textbook/series/get/${seriesId}`);
        const result = await response.json();
        
        if (result.success) {
            const series = result.data;
            document.getElementById('seriesModalTitle').textContent = '编辑教材系列';
            document.getElementById('seriesId').value = series.id;
            document.getElementById('seriesName').value = series.name || '';
            document.getElementById('seriesSlug').value = series.slug || '';
            document.getElementById('seriesIsActive').checked = series.is_active === 1;
            document.getElementById('seriesModal').classList.remove('hidden');
        }
    } catch (error) {
        console.error('Error:', error);
        if (window.customAlert) {
            window.customAlert('获取系列信息失败: ' + error.message);
        } else {
            alert('获取系列信息失败');
        }
    }
}

function closeSeriesModal() {
    document.getElementById('seriesModal').classList.add('hidden');
}

document.getElementById('seriesForm').addEventListener('submit', async function(e) {
    e.preventDefault();
    
    const seriesId = document.getElementById('seriesId').value;
    const formData = {
        name: document.getElementById('seriesName').value.trim(),
        slug: document.getElementById('seriesSlug').value.trim() || null,
        is_active: document.getElementById('seriesIsActive').checked
    };
    
    try {
        let response;
        if (seriesId) {
            response = await fetch(`/api/textbook/series/update/${seriesId}`, {
                method: 'POST',
                headers: {'Content-Type': 'application/json'},
                body: JSON.stringify(formData)
            });
        } else {
            response = await fetch('/api/textbook/series/create', {
                method: 'POST',
                headers: {'Content-Type': 'application/json'},
                body: JSON.stringify(formData)
            });
        }
        
        const result = await response.json();
        
        if (result.success) {
            alert(result.message || '操作成功');
            window.location.reload();
        } else {
            alert('操作失败: ' + result.error);
        }
    } catch (error) {
        console.error('Error:', error);
        alert('操作失败: ' + error.message);
    }
});

// ==================== 教材 CRUD ====================
function showAddTextbookModal() {
    document.getElementById('textbookModalTitle').textContent = '添加教材';
    document.getElementById('textbookForm').reset();
    document.getElementById('textbookId').value = '';
    document.getElementById('textbookModal').classList.remove('hidden');
}

async function showEditTextbookModal(textbookId) {
    try {
        const response = await fetch(`/api/textbook/get/${textbookId}`);
        const result = await response.json();
        
        if (result.success) {
            const textbook = result.data;
            document.getElementById('textbookModalTitle').textContent = '编辑教材';
            document.getElementById('textbookId').value = textbook.id;
            document.getElementById('textbookTitle').value = textbook.official_title || '';
            document.getElementById('textbookStage').value = textbook.stage || '';
            document.getElementById('textbookGrade').value = textbook.grade || '';
            document.getElementById('textbookSemester').value = textbook.semester || '';
            document.getElementById('textbookModal').classList.remove('hidden');
        }
    } catch (error) {
        console.error('Error:', error);
        alert('获取教材信息失败');
    }
}

function closeTextbookModal() {
    document.getElementById('textbookModal').classList.add('hidden');
}

document.getElementById('textbookForm').addEventListener('submit', async function(e) {
    e.preventDefault();
    
    const textbookId = document.getElementById('textbookId').value;
    const formData = {
        series_id: currentSeriesId,
        official_title: document.getElementById('textbookTitle').value.trim(),
        stage: document.getElementById('textbookStage').value || null,
        grade: document.getElementById('textbookGrade').value.trim() || null,
        semester: document.getElementById('textbookSemester').value ? parseInt(document.getElementById('textbookSemester').value) : null
    };
    
    try {
        let response;
        if (textbookId) {
            response = await fetch(`/api/textbook/update/${textbookId}`, {
                method: 'POST',
                headers: {'Content-Type': 'application/json'},
                body: JSON.stringify(formData)
            });
        } else {
            response = await fetch('/api/textbook/create', {
                method: 'POST',
                headers: {'Content-Type': 'application/json'},
                body: JSON.stringify(formData)
            });
        }
        
        const result = await response.json();
        
        if (result.success) {
            if (window.customAlert) {
                window.customAlert(result.message || '操作成功', () => {
                    switchSeries(currentSeriesId);
                    closeTextbookModal();
                });
            } else {
                alert(result.message || '操作成功');
                switchSeries(currentSeriesId);
                closeTextbookModal();
            }
        } else {
            if (window.customAlert) {
                window.customAlert('操作失败: ' + result.error);
            } else {
                alert('操作失败: ' + result.error);
            }
        }
    } catch (error) {
        console.error('Error:', error);
        alert('操作失败: ' + error.message);
    }
});

async function showDeleteTextbookConfirm(textbookId, textbookTitle) {
    if (confirm(`确定要删除教材 "${textbookTitle}" 吗？`)) {
        try {
            const response = await fetch(`/api/textbook/delete/${textbookId}`, {
                method: 'POST',
                headers: {'Content-Type': 'application/json'}
            });
            
            const result = await response.json();
            
            if (result.success) {
                if (window.customAlert) {
                    window.customAlert(result.message || '删除成功', () => {
                        switchSeries(currentSeriesId);
                    });
                } else {
                    alert(result.message || '删除成功');
                    switchSeries(currentSeriesId);
                }
            } else {
                if (window.customAlert) {
                    window.customAlert('删除失败: ' + result.error);
                } else {
                    alert('删除失败: ' + result.error);
                }
            }
        } catch (error) {
            console.error('Error:', error);
            alert('删除失败: ' + error.message);
        }
    }
}

// ==================== 目录节点 CRUD ====================
function showAddCatalogModal(parentId = null, parentNodeType = null) {
    document.getElementById('catalogModalTitle').textContent = parentId ? '添加子节点' : '添加目录节点';
    document.getElementById('catalogForm').reset();
    document.getElementById('catalogId').value = '';
    document.getElementById('catalogTextbookId').value = currentTextbookId;
    document.getElementById('catalogParentId').value = parentId || '';
    
    // 根据父节点类型限制子节点类型
    const nodeTypeSelect = document.getElementById('catalogNodeType');
    const allOptions = nodeTypeSelect.querySelectorAll('option');
    
    // 先显示所有选项
    allOptions.forEach(opt => opt.style.display = '');
    
    if (parentId && parentNodeType) {
        // 有父节点，根据父节点类型限制
        if (parentNodeType === 'chapter') {
            // 章节下只能创建 section
            allOptions.forEach(opt => {
                if (opt.value !== 'section') {
                    opt.style.display = 'none';
                }
            });
            nodeTypeSelect.value = 'section';
        } else if (parentNodeType === 'section') {
            // section 下只能创建 subsection
            allOptions.forEach(opt => {
                if (opt.value !== 'subsection') {
                    opt.style.display = 'none';
                }
            });
            nodeTypeSelect.value = 'subsection';
        } else {
            // subsection 下不能再创建子节点（但这里不应该被调用）
            allOptions.forEach(opt => {
                if (opt.value !== 'subsection') {
                    opt.style.display = 'none';
                }
            });
        }
    } else {
        // 没有父节点，只能创建顶级节点（chapter）
        allOptions.forEach(opt => {
            if (opt.value !== 'chapter') {
                opt.style.display = 'none';
            }
        });
        nodeTypeSelect.value = 'chapter';
    }
    
    document.getElementById('catalogModal').classList.remove('hidden');
}

async function showAddChildCatalogModal(parentId, parentTitle, parentNodeType = null) {
    // 如果未传递父节点类型，则通过API获取
    if (!parentNodeType) {
        try {
            const response = await fetch(`/api/textbook/catalog/get/${parentId}`);
            const result = await response.json();
            
            if (result.success) {
                parentNodeType = result.data.node_type;
            }
        } catch (error) {
            console.error('获取父节点信息失败:', error);
        }
    }
    
    showAddCatalogModal(parentId, parentNodeType);
}

async function showEditCatalogModal(nodeId) {
    try {
        const response = await fetch(`/api/textbook/catalog/get/${nodeId}`);
        const result = await response.json();
        
        if (result.success) {
            const node = result.data;
            document.getElementById('catalogModalTitle').textContent = '编辑目录节点';
            document.getElementById('catalogId').value = node.id;
            document.getElementById('catalogTextbookId').value = node.textbook_id;
            document.getElementById('catalogParentId').value = node.parent_id || '';
            document.getElementById('catalogTitle').value = node.title || '';
            document.getElementById('catalogDisplayNo').value = node.display_no || '';
            
            // 根据父节点类型限制节点类型选择
            const nodeTypeSelect = document.getElementById('catalogNodeType');
            const allOptions = nodeTypeSelect.querySelectorAll('option');
            
            // 先显示所有选项
            allOptions.forEach(opt => opt.style.display = '');
            
            if (node.parent_id) {
                // 有父节点，需要获取父节点类型
                try {
                    const parentResponse = await fetch(`/api/textbook/catalog/get/${node.parent_id}`);
                    const parentResult = await parentResponse.json();
                    
                    if (parentResult.success) {
                        const parentNodeType = parentResult.data.node_type;
                        if (parentNodeType === 'chapter') {
                            // 章节下只能创建 section
                            allOptions.forEach(opt => {
                                if (opt.value !== 'section') {
                                    opt.style.display = 'none';
                                }
                            });
                        } else if (parentNodeType === 'section') {
                            // section 下只能创建 subsection
                            allOptions.forEach(opt => {
                                if (opt.value !== 'subsection') {
                                    opt.style.display = 'none';
                                }
                            });
                        }
                    }
                } catch (error) {
                    console.error('获取父节点信息失败:', error);
                }
            } else {
                // 没有父节点，只能创建顶级节点（chapter）
                allOptions.forEach(opt => {
                    if (opt.value !== 'chapter') {
                        opt.style.display = 'none';
                    }
                });
            }
            
            document.getElementById('catalogNodeType').value = node.node_type || 'chapter';
            document.getElementById('catalogModal').classList.remove('hidden');
        }
    } catch (error) {
        console.error('Error:', error);
        alert('获取节点信息失败');
    }
}

function closeCatalogModal() {
    document.getElementById('catalogModal').classList.add('hidden');
}

document.getElementById('catalogForm').addEventListener('submit', async function(e) {
    e.preventDefault();
    
    const catalogId = document.getElementById('catalogId').value;
    const formData = {
        textbook_id: parseInt(document.getElementById('catalogTextbookId').value),
        parent_id: document.getElementById('catalogParentId').value ? parseInt(document.getElementById('catalogParentId').value) : null,
        node_type: document.getElementById('catalogNodeType').value,
        title: document.getElementById('catalogTitle').value.trim(),
        display_no: document.getElementById('catalogDisplayNo').value.trim() || null
    };
    
    try {
        let response;
        if (catalogId) {
            response = await fetch(`/api/textbook/catalog/update/${catalogId}`, {
                method: 'POST',
                headers: {'Content-Type': 'application/json'},
                body: JSON.stringify(formData)
            });
        } else {
            response = await fetch('/api/textbook/catalog/create', {
                method: 'POST',
                headers: {'Content-Type': 'application/json'},
                body: JSON.stringify(formData)
            });
        }
        
        const result = await response.json();
        
        if (result.success) {
            if (window.customAlert) {
                window.customAlert(result.message || '操作成功', () => {
                    loadTextbookCatalog(currentTextbookId, document.getElementById('currentTextbookTitle').textContent);
                    closeCatalogModal();
                });
            } else {
                alert(result.message || '操作成功');
                loadTextbookCatalog(currentTextbookId, document.getElementById('currentTextbookTitle').textContent);
                closeCatalogModal();
            }
        } else {
            if (window.customAlert) {
                window.customAlert('操作失败: ' + result.error);
            } else {
                alert('操作失败: ' + result.error);
            }
        }
    } catch (error) {
        console.error('Error:', error);
        alert('操作失败: ' + error.message);
    }
});

async function showDeleteCatalogConfirm(nodeId, nodeTitle) {
    if (confirm(`确定要删除节点 "${nodeTitle}" 吗？`)) {
        try {
            const response = await fetch(`/api/textbook/catalog/delete/${nodeId}`, {
                method: 'POST',
                headers: {'Content-Type': 'application/json'}
            });
            
            const result = await response.json();
            
            if (result.success) {
                if (window.customAlert) {
                    window.customAlert(result.message || '删除成功', () => {
                        loadTextbookCatalog(currentTextbookId, document.getElementById('currentTextbookTitle').textContent);
                    });
                } else {
                    alert(result.message || '删除成功');
                    loadTextbookCatalog(currentTextbookId, document.getElementById('currentTextbookTitle').textContent);
                }
            } else {
                if (window.customAlert) {
                    window.customAlert('删除失败: ' + result.error);
                } else {
                    alert('删除失败: ' + result.error);
                }
            }
        } catch (error) {
            console.error('Error:', error);
            alert('删除失败: ' + error.message);
        }
    }
}

// ==================== 知识点关联 CRUD ====================
let currentKpRelationSectionId = null;

async function showAddKpRelationModal(chapterId, chapterTitle) {
    currentKpRelationSectionId = chapterId;
    currentCatalogChapterId = chapterId;
    document.getElementById('kpRelationModalTitle').textContent = `关联知识点 - ${chapterTitle}`;
    document.getElementById('kpRelationModal').classList.remove('hidden');
    
    // 加载已有的关联
    await loadKpRelations(chapterId);
}

function closeKpRelationModal() {
    document.getElementById('kpRelationModal').classList.add('hidden');
    currentCatalogChapterId = null;
}

async function loadKpRelations(chapterId) {
    try {
        const response = await fetch(`/api/textbook/relation/list/${chapterId}`);
        const result = await response.json();
        
        if (result.success) {
            const container = document.getElementById('kpRelationList');
            container.innerHTML = '';
            
            if (result.data.length === 0) {
                container.innerHTML = '<p class="text-gray-500 text-center py-4">暂无关联的知识点</p>';
            } else {
                // 去重：按kp_code去重，保留第一个
                const uniqueRelations = [];
                const seenKpCodes = new Set();
                
                result.data.forEach(relation => {
                    if (!seenKpCodes.has(relation.kp_code)) {
                        seenKpCodes.add(relation.kp_code);
                        uniqueRelations.push(relation);
                    }
                });
                
                uniqueRelations.forEach(relation => {
                    const div = document.createElement('div');
                    div.className = 'flex items-center justify-between p-3 bg-gray-50 rounded-lg';
                    div.innerHTML = `
                        <div>
                            <span class="font-semibold">${relation.kp_code}</span>
                            ${relation.kp_name ? `<span class="text-gray-500 ml-2">${relation.kp_name}</span>` : ''}
                        </div>
                        <button onclick="deleteKpRelation(${relation.id})" class="text-red-600 hover:text-red-800">
                            <i class="ri-delete-bin-line"></i>
                        </button>
                    `;
                    container.appendChild(div);
                });
            }
        }
    } catch (error) {
        console.error('Error:', error);
    }
}

async function addKpRelation() {
    const kpCode = document.getElementById('kpCodeSelect').value;
    if (!kpCode) {
        if (window.customAlert) {
            window.customAlert('请选择知识点');
        } else {
            alert('请选择知识点');
        }
        return;
    }
    
    // 检查是否已存在该关联
    try {
        const checkResponse = await fetch(`/api/textbook/relation/list/${currentCatalogChapterId}`);
        const checkResult = await checkResponse.json();
        
        if (checkResult.success && checkResult.data) {
            const exists = checkResult.data.some(rel => rel.kp_code === kpCode);
            if (exists) {
                if (window.customAlert) {
                    window.customAlert('该知识点已关联，不能重复添加');
                } else {
                    alert('该知识点已关联，不能重复添加');
                }
                return;
            }
        }
    } catch (error) {
        console.error('Error checking existing relations:', error);
    }
    
    try {
        const response = await fetch('/api/textbook/relation/create', {
            method: 'POST',
            headers: {'Content-Type': 'application/json'},
            body: JSON.stringify({
                catalog_chapter_id: currentCatalogChapterId,
                kp_code: kpCode
            })
        });
        
        const result = await response.json();
        
        if (result.success) {
            document.getElementById('kpCodeSelect').value = '';
            await loadKpRelations(currentCatalogChapterId);
            // 刷新section下显示的知识点列表
            if (currentKpRelationSectionId) {
                loadKnowledgePointsForSection(currentKpRelationSectionId);
            }
        } else {
            if (window.customAlert) {
                window.customAlert('添加失败: ' + result.error);
            } else {
                alert('添加失败: ' + result.error);
            }
        }
    } catch (error) {
        console.error('Error:', error);
        if (window.customAlert) {
            window.customAlert('添加失败: ' + error.message);
        } else {
            alert('添加失败: ' + error.message);
        }
    }
}

async function deleteKpRelation(relationId) {
    if (!confirm('确定要删除这个关联吗？')) {
        return;
    }
    
    try {
        const response = await fetch(`/api/textbook/relation/delete/${relationId}`, {
            method: 'POST',
            headers: {'Content-Type': 'application/json'}
        });
        
        const result = await response.json();
        
        if (result.success) {
            await loadKpRelations(currentCatalogChapterId);
            // 刷新section下显示的知识点列表
            if (currentKpRelationSectionId) {
                loadKnowledgePointsForSection(currentKpRelationSectionId);
            }
        } else {
            alert('删除失败: ' + result.error);
        }
    } catch (error) {
        console.error('Error:', error);
        alert('删除失败: ' + error.message);
    }
}

// 点击模态框外部关闭
document.getElementById('seriesModal').addEventListener('click', function(e) {
    if (e.target === this) closeSeriesModal();
});
document.getElementById('textbookModal').addEventListener('click', function(e) {
    if (e.target === this) closeTextbookModal();
});
document.getElementById('catalogModal').addEventListener('click', function(e) {
    if (e.target === this) closeCatalogModal();
});
document.getElementById('kpRelationModal').addEventListener('click', function(e) {
    if (e.target === this) closeKpRelationModal();
});
</script>
{% endblock %}