// API基础地址
const API_BASE = '';

// 状态
let articles = [];
let currentPage = 1;
let pageSize = 20;
let totalCount = 0;
let selectedIds = new Set();
let currentArticleId = null;

// 页面加载
document.addEventListener('DOMContentLoaded', () => {
    loadArticles();
    loadCategories();
    
    // 搜索防抖
    let searchTimeout;
    document.getElementById('search-input').addEventListener('input', (e) => {
        clearTimeout(searchTimeout);
        searchTimeout = setTimeout(() => {
            currentPage = 1;
            loadArticles();
        }, 300);
    });
    
    // 分类筛选
    document.getElementById('category-filter').addEventListener('change', () => {
        currentPage = 1;
        loadArticles();
    });
});

// 加载文章列表
async function loadArticles() {
    const keyword = document.getElementById('search-input').value.trim();
    const category = document.getElementById('category-filter').value;
    
    const params = new URLSearchParams({
        limit: pageSize,
        offset: (currentPage - 1) * pageSize
    });
    
    if (keyword) {
        const response = await fetch(`${API_BASE}/api/articles/search?q=${encodeURIComponent(keyword)}${category ? '&category=' + encodeURIComponent(category) : ''}`);
        const data = await response.json();
        
        if (data.success) {
            articles = data.articles;
            totalCount = data.count;
        }
    } else {
        const response = await fetch(`${API_BASE}/api/articles?${params.toString()}`);
        const data = await response.json();
        
        if (data.success) {
            articles = data.articles;
            totalCount = data.count;
        }
    }
    
    displayArticles();
    updatePagination();
    updateStats();
}

// 加载分类列表
async function loadCategories() {
    try {
        const response = await fetch(`${API_BASE}/api/articles?limit=1000`);
        const data = await response.json();
        
        if (data.success) {
            const categories = new Set();
            data.articles.forEach(a => {
                if (a.category) categories.add(a.category);
            });
            
            const select = document.getElementById('category-filter');
            select.innerHTML = '<option value="">全部分类</option>' + 
                Array.from(categories).map(c => `<option value="${escapeHtml(c)}">${escapeHtml(c)}</option>`).join('');
        }
    } catch (error) {
        console.error('加载分类失败:', error);
    }
}

// 显示文章列表
function displayArticles() {
    const container = document.getElementById('articles-list');
    
    if (articles.length === 0) {
        container.innerHTML = '<div class="empty-text">暂无文章</div>';
        return;
    }
    
    container.innerHTML = articles.map(article => {
        const productNames = safeParseJSON(article.product_names, []);
        const keywords = safeParseJSON(article.keywords, []);
        
        return `
            <div class="article-card ${selectedIds.has(article.id) ? 'selected' : ''}" id="article-${article.id}">
                <div class="article-card-header">
                    <label class="checkbox-wrapper">
                        <input type="checkbox" class="article-select" 
                            ${selectedIds.has(article.id) ? 'checked' : ''} 
                            onchange="toggleSelect(${article.id})">
                    </label>
                    <div class="article-title" onclick="showDetail(${article.id})">
                        ${escapeHtml(productNames.join(', ') || '未命名')}
                    </div>
                    <div class="article-actions">
                        <button onclick="editArticle(${article.id})" class="btn btn-sm btn-secondary">
                            <i class="ri-edit-line"></i>
                        </button>
                        <button onclick="deleteArticle(${article.id})" class="btn btn-sm btn-danger">
                            <i class="ri-delete-bin-line"></i>
                        </button>
                    </div>
                </div>
                <div class="article-meta">
                    ${article.category ? `<span class="article-category">${escapeHtml(article.category)}</span>` : ''}
                    <span><i class="ri-link"></i> ${escapeHtml(article.source || '未知来源')}</span>
                    <span><i class="ri-calendar-line"></i> ${formatDate(article.fetch_date)}</span>
                </div>
                <div class="article-summary">${escapeHtml(article.summary || '')}</div>
                ${keywords.length > 0 ? `
                    <div class="article-tags">
                        ${keywords.slice(0, 5).map(k => `<span class="article-tag">${escapeHtml(k)}</span>`).join('')}
                    </div>
                ` : ''}
            </div>
        `;
    }).join('');
}

// 更新分页
function updatePagination() {
    const totalPages = Math.ceil(totalCount / pageSize);
    document.getElementById('page-info').textContent = `第 ${currentPage} / ${totalPages || 1} 页`;
    
    document.getElementById('prev-btn').disabled = currentPage <= 1;
    document.getElementById('next-btn').disabled = currentPage >= totalPages;
}

// 更新统计
function updateStats() {
    document.getElementById('total-count').textContent = `${totalCount} 篇文章`;
}

// 上一页
function prevPage() {
    if (currentPage > 1) {
        currentPage--;
        loadArticles();
    }
}

// 下一页
function nextPage() {
    const totalPages = Math.ceil(totalCount / pageSize);
    if (currentPage < totalPages) {
        currentPage++;
        loadArticles();
    }
}

// 刷新列表
function refreshList() {
    loadArticles();
}

// 全选/取消全选
function toggleSelectAll() {
    const checked = document.getElementById('select-all').checked;
    
    if (checked) {
        articles.forEach(a => selectedIds.add(a.id));
    } else {
        selectedIds.clear();
    }
    
    displayArticles();
    updateBatchActions();
}

// 切换单个选择
function toggleSelect(id) {
    if (selectedIds.has(id)) {
        selectedIds.delete(id);
    } else {
        selectedIds.add(id);
    }
    
    updateBatchActions();
}

// 更新批量操作按钮
function updateBatchActions() {
    const batchActions = document.getElementById('batch-actions');
    
    if (selectedIds.size > 0) {
        batchActions.style.display = 'flex';
        document.getElementById('selected-count').textContent = `已选 ${selectedIds.size} 篇`;
    } else {
        batchActions.style.display = 'none';
    }
}

// 显示详情
async function showDetail(id) {
    currentArticleId = id;
    const article = articles.find(a => a.id === id);
    
    if (!article) {
        const response = await fetch(`${API_BASE}/api/articles/${id}`);
        const data = await response.json();
        if (data.success) {
            Object.assign(article, data.article);
        }
    }
    
    const productNames = safeParseJSON(article.product_names, []);
    const keywords = safeParseJSON(article.keywords, []);
    
    const body = document.getElementById('detail-body');
    body.innerHTML = `
        <div class="detail-section">
            <h4><i class="ri-price-tag-3-line"></i> 产品名称</h4>
            <p>${escapeHtml(productNames.join(', '))}</p>
        </div>
        <div class="detail-meta" style="display: flex; gap: 20px; background: #f8f9fa; padding: 15px; border-radius: 8px; margin-bottom: 20px;">
            <div><strong>分类:</strong> ${escapeHtml(article.category || '未分类')}</div>
            <div><strong>来源:</strong> ${escapeHtml(article.source)}</div>
            <div><strong>时间:</strong> ${formatDate(article.fetch_date)}</div>
        </div>
        ${article.url ? `<div class="detail-section"><h4><i class="ri-link"></i> 原文链接</h4><a href="${escapeHtml(article.url)}" target="_blank">${escapeHtml(article.url)}</a></div>` : ''}
        ${keywords.length > 0 ? `<div class="detail-section"><h4><i class="ri-keyword-line"></i> 关键词</h4><p>${escapeHtml(keywords.join(', '))}</p></div>` : ''}
        <div class="detail-section">
            <h4><i class="ri-file-text-line"></i> 摘要</h4>
            <p>${escapeHtml(article.summary || '无')}</p>
        </div>
        <div class="detail-section">
            <h4><i class="ri-align-left"></i> 内容</h4>
            <div class="detail-content">${escapeHtml(article.content || '无内容')}</div>
        </div>
    `;
    
    document.getElementById('detail-modal').classList.add('active');
}

// 显示添加模态框
function showAddModal() {
    currentArticleId = null;
    document.getElementById('modal-title').innerHTML = '<i class="ri-file-add-line"></i> 添加文章';
    document.getElementById('article-form').reset();
    document.getElementById('article-modal').classList.add('active');
}

// 编辑文章
function editArticle(id) {
    const article = articles.find(a => a.id === id);
    if (!article) return;
    
    currentArticleId = id;
    document.getElementById('modal-title').innerHTML = '<i class="ri-edit-line"></i> 编辑文章';
    
    const productNames = safeParseJSON(article.product_names, []);
    const keywords = safeParseJSON(article.keywords, []);
    
    document.getElementById('article-id').value = id;
    document.getElementById('article-products').value = productNames.join(', ');
    document.getElementById('article-category').value = article.category || '';
    document.getElementById('article-keywords').value = keywords.join(', ');
    document.getElementById('article-summary').value = article.summary || '';
    document.getElementById('article-content').value = article.content || '';
    document.getElementById('article-source').value = article.source || '';
    document.getElementById('article-url').value = article.url || '';
    
    document.getElementById('article-modal').classList.add('active');
}

// 编辑当前文章
function editCurrentArticle() {
    if (currentArticleId) {
        closeModal('detail-modal');
        editArticle(currentArticleId);
    }
}

// 保存文章
async function saveArticle() {
    const id = document.getElementById('article-id').value;
    const products = document.getElementById('article-products').value.trim();
    const summary = document.getElementById('article-summary').value.trim();
    const content = document.getElementById('article-content').value.trim();
    const source = document.getElementById('article-source').value.trim();
    
    if (!products || !summary || !content || !source) {
        showToast('请填写必填字段', 'error');
        return;
    }
    
    const articleData = {
        product_names: products.split(',').map(p => p.trim()),
        category: document.getElementById('article-category').value.trim(),
        keywords: document.getElementById('article-keywords').value.split(',').map(k => k.trim()).filter(k => k),
        summary: summary,
        content: content,
        source: source,
        url: document.getElementById('article-url').value.trim()
    };
    
    try {
        if (id) {
            // 更新 - 先删除再添加
            await fetch(`${API_BASE}/api/articles/${id}`, { method: 'DELETE' });
        }
        
        const response = await fetch(`${API_BASE}/api/articles`, {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' },
            body: JSON.stringify(articleData)
        });
        
        const data = await response.json();
        
        if (data.success) {
            showToast(id ? '文章已更新' : '文章已添加', 'success');
            closeModal('article-modal');
            loadArticles();
        } else {
            showToast('保存失败: ' + data.error, 'error');
        }
    } catch (error) {
        showToast('保存出错', 'error');
    }
}

// 删除文章
async function deleteArticle(id) {
    if (!confirm('确定要删除这篇文章吗？')) return;
    
    try {
        const response = await fetch(`${API_BASE}/api/articles/${id}`, {
            method: 'DELETE'
        });
        
        const data = await response.json();
        
        if (data.success) {
            showToast('文章已删除', 'success');
            loadArticles();
        } else {
            showToast('删除失败', 'error');
        }
    } catch (error) {
        showToast('删除出错', 'error');
    }
}

// 删除当前文章
function deleteCurrentArticle() {
    if (currentArticleId) {
        deleteArticle(currentArticleId);
        closeModal('detail-modal');
    }
}

// 批量删除
async function batchDelete() {
    if (selectedIds.size === 0) return;
    
    if (!confirm(`确定要删除选中的 ${selectedIds.size} 篇文章吗？`)) return;
    
    let deleted = 0;
    for (const id of selectedIds) {
        try {
            await fetch(`${API_BASE}/api/articles/${id}`, { method: 'DELETE' });
            deleted++;
        } catch (error) {
            console.error(`删除 ${id} 失败:`, error);
        }
    }
    
    selectedIds.clear();
    showToast(`已删除 ${deleted} 篇文章`, 'success');
    loadArticles();
}

// 导出文章
async function exportArticles() {
    const keyword = document.getElementById('search-input').value.trim();
    const category = document.getElementById('category-filter').value;
    
    let exportArticles = articles;
    
    // 如果有搜索条件，获取全部匹配的
    if (keyword || category) {
        const params = new URLSearchParams();
        if (keyword) params.append('q', keyword);
        if (category) params.append('category', category);
        
        const response = await fetch(`${API_BASE}/api/articles/search?${params.toString()}`);
        const data = await response.json();
        if (data.success) {
            exportArticles = data.articles;
        }
    }
    
    if (exportArticles.length === 0) {
        showToast('没有可导出的文章', 'error');
        return;
    }
    
    // 导出为 JSON
    const exportData = exportArticles.map(a => ({
        product_names: safeParseJSON(a.product_names, []),
        category: a.category,
        keywords: safeParseJSON(a.keywords, []),
        summary: a.summary,
        content: a.content,
        source: a.source,
        url: a.url
    }));
    
    const blob = new Blob([JSON.stringify(exportData, null, 2)], { type: 'application/json' });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = `articles_${new Date().toISOString().split('T')[0]}.json`;
    a.click();
    URL.revokeObjectURL(url);
    
    showToast(`已导出 ${exportArticles.length} 篇文章`, 'success');
}

// 关闭模态框
function closeModal(modalId) {
    document.getElementById(modalId).classList.remove('active');
}

// 显示提示
function showToast(message, type = '') {
    const toast = document.getElementById('toast');
    toast.textContent = message;
    toast.className = `toast active ${type}`;
    
    setTimeout(() => {
        toast.classList.remove('active');
    }, 3000);
}

// HTML转义
function escapeHtml(text) {
    if (!text) return '';
    const div = document.createElement('div');
    div.textContent = text;
    return div.innerHTML;
}

// 安全解析JSON
function safeParseJSON(str, defaultVal) {
    try {
        return JSON.parse(str || JSON.stringify(defaultVal));
    } catch {
        return defaultVal;
    }
}

// 日期格式化
function formatDate(dateString) {
    if (!dateString) return '-';
    const date = new Date(dateString);
    return date.toLocaleString('zh-CN', {
        year: 'numeric',
        month: '2-digit',
        day: '2-digit',
        hour: '2-digit',
        minute: '2-digit'
    });
}