// 当DOM加载完成后执行
document.addEventListener('DOMContentLoaded', function() {
    let currentPage = 0;
    let isLoading = false;
    let hasMore = true;
    
    // 初始化加载第一页数据
    loadAnalyses();
    
    // 无限滚动加载
    let scrollTimeout;
    window.addEventListener('scroll', function() {
        // 防抖处理，避免频繁触发
        clearTimeout(scrollTimeout);
        scrollTimeout = setTimeout(function() {
            if (isLoading || !hasMore) return;
            
            const scrollPosition = window.pageYOffset;
            const windowSize = window.innerHeight;
            const bodyHeight = document.body.offsetHeight;
            
            // 当滚动到距离底部200px时加载更多
            if (bodyHeight - (scrollPosition + windowSize) < 200) {
                loadAnalyses();
            }
        }, 100);
    });
    
    // 返回顶部按钮功能
    const backToTopBtn = document.getElementById('backToTop');
    
    window.addEventListener('scroll', function() {
        if (window.pageYOffset > 300) {
            backToTopBtn.style.display = 'block';
        } else {
            backToTopBtn.style.display = 'none';
        }
    });
    
    backToTopBtn.addEventListener('click', function() {
        window.scrollTo({
            top: 0,
            behavior: 'smooth'
        });
    });
    
    // 加载分析数据
    function loadAnalyses() {
        if (isLoading || !hasMore) return;
        
        isLoading = true;
        showLoading();
        
        const xhr = new XMLHttpRequest();
        const url = CONTEXT_PATH + '/AnalysisTimelineServlet?action=loadMore&page=' + currentPage + '&pageSize=20';
        console.log('请求URL:', url);
        
        xhr.open('GET', url, true);
        xhr.timeout = 10000; // 10秒超时
        
        xhr.onload = function() {
            isLoading = false;
            hideLoading();
            
            if (xhr.status === 200) {
                try {
                    const response = JSON.parse(xhr.responseText);
                    
                    if (!response.success) {
                        console.error('服务器返回错误:', response.error);
                        showError('服务器错误: ' + response.error);
                        return;
                    }
                    
                    if (response.data && response.data.length > 0) {
                        renderAnalyses(response.data);
                        currentPage++;
                        
                        // 根据hasMore字段判断是否还有更多数据
                        if (!response.hasMore) {
                            hasMore = false;
                            showNoMore();
                        }
                    } else {
                        hasMore = false;
                        showNoMore();
                    }
                } catch (e) {
                    console.error('解析响应数据时出错:', e);
                    showError('解析数据时出错: ' + e.message);
                }
            } else {
                console.error('请求失败，状态码:', xhr.status);
                showError('请求失败，状态码: ' + xhr.status);
            }
        };
        
        xhr.onerror = function() {
            isLoading = false;
            hideLoading();
            console.error('网络请求失败');
            showError('网络请求失败，请检查网络连接');
        };
        
        xhr.ontimeout = function() {
            isLoading = false;
            hideLoading();
            console.error('请求超时');
            showError('请求超时，请检查网络连接');
        };
        
        xhr.send();
    }
    
    // 渲染分析数据到时间轴
    function renderAnalyses(analyses) {
        const timeline = document.getElementById('timeline');
        
        analyses.forEach((analysis, index) => {
            const timelineItem = createTimelineItem(analysis, currentPage * 20 + index);
            timeline.appendChild(timelineItem);
        });
    }
    
    // 创建单个时间轴项目
    function createTimelineItem(analysis, index) {
        const item = document.createElement('div');
        item.className = 'timeline-item';
        
        // 格式化日期
        const publishDate = formatDate(new Date(analysis.publishTime));
        const analysisDate = analysis.analysisTime ? 
            formatDate(new Date(analysis.analysisTime)) : '未知时间';
        
        // 处理分析内容，将**加粗**文本转换为HTML
        let analysisHtml = analysis.analysis || '暂无分析内容';
        analysisHtml = analysisHtml.replace(/\*\*(.*?)\*\*/g, '<strong>$1</strong>');
        analysisHtml = analysisHtml.replace(/\n/g, '<br>');
        
        // 处理内容文本，添加展开/收起功能
        const contentText = analysis.content || '无详细内容';
        const isContentLong = contentText.length > 150;
        const displayContent = isContentLong ? contentText.substring(0, 150) + '...' : contentText;
        
        item.innerHTML = `
            <div class="timeline-content">
                <div class="timeline-date">${publishDate}</div>
                <h3 class="timeline-title">${analysis.title}</h3>
                <div class="timeline-meta">
                    <span>消息ID: ${analysis.telegraphId}</span>
                    <span>分析时间: ${analysisDate}</span>
                </div>
                <div class="timeline-content-text" id="content-${analysis.id}">
                    ${displayContent}
                </div>
                ${isContentLong ? `<div class="read-more" onclick="toggleContent('${analysis.id}', '${escapeHtml(contentText)}')">展开全文</div>` : ''}
                <div class="timeline-analysis">
                    <div class="analysis-header">
                        <i class="fas fa-brain"></i>
                        DeepSeek智能分析
                    </div>
                    <div class="analysis-content">
                        ${analysisHtml}
                    </div>
                </div>
            </div>
        `;
        
        // 添加延迟动画效果
        item.style.animationDelay = `${index * 0.1}s`;
        
        return item;
    }
    
    // 格式化日期为YYYY-MM-DD HH:MM格式
    function formatDate(date) {
        const year = date.getFullYear();
        const month = String(date.getMonth() + 1).padStart(2, '0');
        const day = String(date.getDate()).padStart(2, '0');
        const hours = String(date.getHours()).padStart(2, '0');
        const minutes = String(date.getMinutes()).padStart(2, '0');
        
        return `${year}-${month}-${day} ${hours}:${minutes}`;
    }
    
    // 显示加载指示器
    function showLoading() {
        const loading = document.getElementById('loading');
        const noMore = document.getElementById('noMore');
        
        loading.style.display = 'block';
        noMore.style.display = 'none';
    }
    
    // 隐藏加载指示器
    function hideLoading() {
        document.getElementById('loading').style.display = 'none';
    }
    
    // 显示无更多内容
    function showNoMore() {
        const loading = document.getElementById('loading');
        const noMore = document.getElementById('noMore');
        
        loading.style.display = 'none';
        noMore.style.display = 'block';
    }
    
    // 显示错误信息
    function showError(message) {
        // 简单的错误提示
        const errorDiv = document.createElement('div');
        errorDiv.style.cssText = `
            position: fixed;
            top: 20px;
            right: 20px;
            background: #e74c3c;
            color: white;
            padding: 15px 20px;
            border-radius: 5px;
            box-shadow: 0 4px 12px rgba(0,0,0,0.15);
            z-index: 1000;
            max-width: 300px;
            font-family: inherit;
        `;
        errorDiv.innerHTML = `
            <strong>错误</strong>: ${message}
            <button onclick="this.parentElement.remove()" style="
                background: none;
                border: none;
                color: white;
                margin-left: 10px;
                cursor: pointer;
                font-size: 16px;
            ">×</button>
        `;
        
        document.body.appendChild(errorDiv);
        
        // 5秒后自动移除错误提示
        setTimeout(() => {
            if (errorDiv.parentElement) {
                errorDiv.remove();
            }
        }, 5000);
    }
    
    // 转义HTML特殊字符
    function escapeHtml(text) {
        const div = document.createElement('div');
        div.textContent = text;
        return div.innerHTML;
    }
    
    // 全局函数，用于切换内容展开/收起
    window.toggleContent = function(id, fullContent) {
        const contentElement = document.getElementById('content-' + id);
        const readMoreElement = contentElement.nextElementSibling;
        
        if (contentElement.classList.contains('expanded')) {
            // 收起
            const shortContent = fullContent.substring(0, 150) + '...';
            contentElement.innerHTML = shortContent;
            contentElement.classList.remove('expanded');
            if (readMoreElement && readMoreElement.classList.contains('read-more')) {
                readMoreElement.textContent = '展开全文';
            }
        } else {
            // 展开
            contentElement.innerHTML = fullContent;
            contentElement.classList.add('expanded');
            if (readMoreElement && readMoreElement.classList.contains('read-more')) {
                readMoreElement.textContent = '收起';
            }
        }
    };
});