重构下载队列显示逻辑和控制机制

新功能:
- 队列显示所有任务状态（排队中、下载中、已完成、失败）
- 详细任务信息显示：小说名称 - ID - 添加时间 - 状态
- 完整的任务生命周期管理和时间记录
- 任务管理中心替代简单下载队列

控制机制改进:
- 移除前端队列判断逻辑，完全由后台队列系统管理
- 自动任务调度和优先级控制
- 智能队列处理和状态同步

状态管理优化:
- 实时状态更新（排队中/下载中/已完成/失败）
- 不同状态的视觉标识（颜色、图标、动画）
- 当前下载任务高亮显示

时间记录功能:
- 记录任务添加时间、开始时间、完成时间
- 本地时间格式显示
- 完整的任务历史追踪

用户体验提升:
- 任务管理中心成为核心功能
- 清晰的任务生命周期可视化
- 更好的错误处理和重试机制
- 已完成任务直接下载链接

server.py

@@ -13,15 +13,23 @@ TASK_QUEUE = queue.Queue()
 STATUS = {}
 FILE_PATHS = {}
 NAMES = {}
+TASK_DETAILS = {}  # 存储任务详细信息，包括时间戳等
 
 # 后台下载任务处理线程
 def process_queue():
+    from datetime import datetime
+
     while True:
         try:
             book_id = TASK_QUEUE.get(timeout=1)  # 添加超时避免无限等待
             if book_id in STATUS and STATUS[book_id] != "queued":
                 continue  # 跳过已经处理过的任务
 
+            # 记录开始时间
+            start_time = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
+            if book_id in TASK_DETAILS:
+                TASK_DETAILS[book_id]["start_time"] = start_time
+
             STATUS[book_id] = "in-progress"
             save_path = os.path.join(DOWNLOAD_ROOT, book_id)
             os.makedirs(save_path, exist_ok=True)
@@ -36,17 +44,28 @@ def process_queue():
                 filename = f"{name}.txt"
                 path = os.path.join(save_path, filename)
 
+                # 记录完成时间
+                complete_time = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
+
                 if os.path.exists(path):
                     FILE_PATHS[book_id] = f"/files/{book_id}/{filename}"
                     NAMES[book_id] = name
                     STATUS[book_id] = "done"
+                    if book_id in TASK_DETAILS:
+                        TASK_DETAILS[book_id]["complete_time"] = complete_time
+                        TASK_DETAILS[book_id]["name"] = name
                     print(f"下载完成: {name}")
                 else:
                     STATUS[book_id] = "error"
+                    if book_id in TASK_DETAILS:
+                        TASK_DETAILS[book_id]["complete_time"] = complete_time
                     print(f"下载失败: 文件不存在 - {book_id}")
 
             except Exception as e:
                 STATUS[book_id] = "error"
+                complete_time = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
+                if book_id in TASK_DETAILS:
+                    TASK_DETAILS[book_id]["complete_time"] = complete_time
                 print(f"下载异常: {book_id} - {str(e)}")
 
         except:
@@ -293,9 +312,10 @@ def root():
             padding: 1rem;
             border-bottom: 1px solid #e2e8f0;
             display: flex;
-            align-items: center;
+            align-items: flex-start;
             justify-content: space-between;
             transition: background 0.2s ease;
+            min-height: 80px;
         }
 
         .list-item:hover {
@@ -453,11 +473,11 @@ def root():
                 <div id="downloadResult" class="download-result"></div>
             </div>
 
-            <!-- 下载队列 -->
+            <!-- 任务管理中心 -->
             <div class="card">
                 <div class="card-title">
-                    <i class="fas fa-clock"></i>
-                    下载队列
+                    <i class="fas fa-tasks"></i>
+                    任务管理中心
                     <button id="refreshTasks" class="btn btn-secondary btn-small" style="margin-left: auto;">
                         <i class="fas fa-sync-alt"></i>
                     </button>
@@ -612,7 +632,7 @@ def root():
             // 解析输入的ID
             const ids = book_ids.split(/[\s,;]+/).filter(id => id);
 
-            // 先将所有ID加入队列
+            // 将所有ID加入队列，队列系统会自动管理执行
             for (const bid of ids) {
                 await fetch(`/enqueue?book_id=${encodeURIComponent(bid)}`);
             }
@@ -622,21 +642,7 @@ def root():
 
             // 立即刷新队列显示
             fetchTasks();
-            showNotification(`已添加 ${ids.length} 个任务到队列`, 'success');
-
-            // 检查是否有正在进行的任务
-            const tasks = await fetch('/tasks').then(res => res.json());
-            const activeTasks = tasks.filter(t => t.status === 'in-progress');
-
-            // 如果没有正在进行的任务，开始处理第一个排队的任务
-            if (activeTasks.length === 0) {
-                const queuedTasks = tasks.filter(t => t.status === 'queued');
-                if (queuedTasks.length > 0) {
-                    // 开始下载第一个排队的任务
-                    const firstTask = queuedTasks[0];
-                    startDirectDownload(firstTask.book_id);
-                }
-            }
+            showNotification(`已添加 ${ids.length} 个任务到队列，队列系统将自动处理`, 'success');
 
             setButtonLoading(btn, false);
         } catch (error) {
@@ -645,154 +651,8 @@ def root():
         }
     });
 
-    // 全局变量跟踪下载状态
-    let isDownloading = false;
+    // 全局变量跟踪当前下载状态（仅用于UI显示）
     let currentDownloadId = null;
-
-    // 直接下载函数
-    async function startDirectDownload(bookId) {
-        if (isDownloading) {
-            console.log('已有下载任务在进行中，跳过');
-            return;
-        }
-
-        isDownloading = true;
-        currentDownloadId = bookId;
-
-        try {
-            // 重置并显示进度条
-            const progressContainer = document.getElementById('progress');
-            const progBar = document.getElementById('progBar');
-            const progText = document.getElementById('progText');
-
-            progBar.style.width = '0%';
-            progText.innerText = '0%';
-            progressContainer.style.display = 'block';
-            progressContainer.classList.add('fade-in');
-
-            // 清空之前的下载结果
-            const resultDiv = document.getElementById('downloadResult');
-            resultDiv.innerHTML = '';
-
-            showNotification(`开始下载小说 ${NAMES[bookId] || bookId}...`, 'info');
-
-            const response = await fetch(`/download?book_ids=${encodeURIComponent(bookId)}`);
-
-            if (!response.ok) {
-                throw new Error(`HTTP ${response.status}: ${response.statusText}`);
-            }
-
-            const total = response.headers.get('Content-Length');
-            const reader = response.body.getReader();
-            let received = 0;
-            const chunks = [];
-
-            function read() {
-                return reader.read().then(({done, value})=>{
-                    if (done) {
-                        try {
-                            const blob = new Blob(chunks, {type: response.headers.get('Content-Type')});
-                            const url = URL.createObjectURL(blob);
-                            const cd = response.headers.get('Content-Disposition');
-                            let filename = 'download.txt';
-                            if (cd) {
-                                const match = cd.match(/filename[*]?=['"]?([^'";\r\n]+)['"]?/);
-                                if (match) filename = decodeURIComponent(match[1]);
-                            }
-
-                            // 生成下载链接
-                            const link = document.createElement('a');
-                            link.href = url;
-                            link.download = filename;
-                            link.className = 'download-link fade-in';
-                            link.innerHTML = `<i class="fas fa-download"></i> ${filename}`;
-
-                            resultDiv.innerHTML = '';
-                            resultDiv.appendChild(link);
-
-                            // 隐藏进度条
-                            progressContainer.style.display = 'none';
-
-                            showNotification(`下载完成：${filename}`, 'success');
-
-                            // 标记下载完成
-                            isDownloading = false;
-                            currentDownloadId = null;
-
-                            // 刷新任务列表和已下载列表
-                            fetchTasks();
-                            fetchCompleted();
-
-                            // 检查是否还有排队的任务
-                            setTimeout(async () => {
-                                try {
-                                    const tasks = await fetch('/tasks').then(res => res.json());
-                                    const queuedTasks = tasks.filter(t => t.status === 'queued');
-                                    if (queuedTasks.length > 0 && !isDownloading) {
-                                        startDirectDownload(queuedTasks[0].book_id);
-                                    }
-                                } catch (error) {
-                                    console.error('检查队列任务失败:', error);
-                                }
-                            }, 1000);
-
-                        } catch (error) {
-                            console.error('处理下载结果失败:', error);
-                            showNotification('处理下载结果失败', 'error');
-                        }
-                        return;
-                    }
-
-                    chunks.push(value);
-                    received += value.length;
-
-                    // 更新进度条
-                    if (total && parseInt(total) > 0) {
-                        const percent = Math.min(100, Math.round((received / parseInt(total)) * 100));
-                        progBar.style.width = percent + '%';
-                        progText.innerText = percent + '%';
-                    } else {
-                        // 如果没有总长度信息，显示已接收的数据量
-                        const mb = (received / (1024 * 1024)).toFixed(1);
-                        progText.innerText = `已下载 ${mb} MB`;
-                        // 使用动画效果显示进度
-                        const animatedPercent = Math.min(90, (received / 1000000) * 10); // 假设进度
-                        progBar.style.width = animatedPercent + '%';
-                    }
-
-                    return read();
-                });
-            }
-
-            await read();
-
-        } catch (error) {
-            console.error('下载失败:', error);
-
-            // 隐藏进度条
-            const progressContainer = document.getElementById('progress');
-            progressContainer.style.display = 'none';
-
-            showNotification(`下载失败：${error.message}`, 'error');
-
-            // 标记下载完成（即使失败）
-            isDownloading = false;
-            currentDownloadId = null;
-
-            // 即使失败也要继续处理下一个任务
-            setTimeout(async () => {
-                try {
-                    const tasks = await fetch('/tasks').then(res => res.json());
-                    const queuedTasks = tasks.filter(t => t.status === 'queued');
-                    if (queuedTasks.length > 0 && !isDownloading) {
-                        startDirectDownload(queuedTasks[0].book_id);
-                    }
-                } catch (error) {
-                    console.error('检查队列任务失败:', error);
-                }
-            }, 2000);
-        }
-    }
     // 全局变量存储任务名称
     let NAMES = {};
 
@@ -800,7 +660,6 @@ def root():
     function fetchTasks() {
         fetch('/tasks').then(res => res.json()).then(data => {
             const container = document.getElementById('taskList');
-            const activeTasks = data.filter(task => task.status !== 'done');
 
             // 更新全局名称缓存
             data.forEach(task => {
@@ -809,13 +668,13 @@ def root():
                 }
             });
 
-            if (activeTasks.length === 0) {
-                container.innerHTML = '<div class="list-item"><span style="color: #a0aec0;"><i class="fas fa-check"></i> 暂无下载任务</span></div>';
+            if (data.length === 0) {
+                container.innerHTML = '<div class="list-item"><span style="color: #a0aec0;"><i class="fas fa-inbox"></i> 暂无任务</span></div>';
                 return;
             }
 
             container.innerHTML = '';
-            activeTasks.forEach((task, index) => {
+            data.forEach((task, index) => {
                 const div = document.createElement('div');
                 div.className = 'list-item fade-in';
                 div.setAttribute('data-book-id', task.book_id);
@@ -823,18 +682,21 @@ def root():
                 const statusClass = {
                     'queued': 'status-queued',
                     'in-progress': 'status-progress',
+                    'done': 'status-done',
                     'error': 'status-error'
                 }[task.status] || 'status-queued';
 
                 const statusIcon = {
                     'queued': 'fas fa-clock',
                     'in-progress': 'fas fa-spinner fa-spin',
+                    'done': 'fas fa-check-circle',
                     'error': 'fas fa-exclamation-triangle'
                 }[task.status] || 'fas fa-clock';
 
                 const statusText = {
-                    'queued': index === 0 ? '即将开始' : '排队中',
+                    'queued': '排队中',
                     'in-progress': '下载中',
+                    'done': '已完成',
                     'error': '失败'
                 }[task.status] || '未知';
 
@@ -842,12 +704,41 @@ def root():
                 const isCurrentDownload = task.book_id === currentDownloadId;
                 const extraClass = isCurrentDownload ? ' current-download' : '';
 
+                // 构建任务信息显示
+                const taskInfo = `${task.name || task.book_id} - ID: [${task.book_id}]`;
+                const timeInfo = `添加时间: ${task.add_time}`;
+                const statusInfo = `状态: ${statusText}`;
+
                 div.innerHTML = `
-                    <span><i class="fas fa-book"></i> ${task.name || task.book_id}</span>
+                    <div style="flex: 1;">
+                        <div style="font-weight: 500; margin-bottom: 4px;">
+                            <i class="fas fa-book"></i> ${taskInfo}
+                        </div>
+                        <div style="font-size: 0.8rem; color: #6b7280; margin-bottom: 2px;">
+                            <i class="fas fa-clock"></i> ${timeInfo}
+                        </div>
+                        <div style="font-size: 0.8rem; color: #6b7280;">
+                            ${task.start_time ? `<i class="fas fa-play"></i> 开始: ${task.start_time}` : ''}
+                            ${task.complete_time ? `<i class="fas fa-flag-checkered"></i> 完成: ${task.complete_time}` : ''}
+                        </div>
+                    </div>
                     <span class="status-badge ${statusClass}${extraClass}">
-                        <i class="${statusIcon}"></i> ${statusText}
+                        <i class="${statusIcon}"></i> ${statusInfo}
                     </span>
                 `;
+
+                // 如果是已完成的任务，添加下载链接
+                if (task.status === 'done') {
+                    const downloadBtn = document.createElement('a');
+                    downloadBtn.href = `/files/${task.book_id}/${task.name}.txt`;
+                    downloadBtn.download = `${task.name}.txt`;
+                    downloadBtn.className = 'btn btn-secondary btn-small';
+                    downloadBtn.style.marginLeft = '8px';
+                    downloadBtn.innerHTML = '<i class="fas fa-download"></i>';
+                    downloadBtn.title = '下载文件';
+                    div.querySelector('.status-badge').parentNode.appendChild(downloadBtn);
+                }
+
                 container.appendChild(div);
             });
         }).catch(error => {
@@ -976,18 +867,11 @@ def root():
         // 自动刷新队列 - 更频繁的刷新以保持同步
         setInterval(() => {
             fetchTasks();
-            // 如果有下载任务在进行，检查是否需要启动下一个
-            if (!isDownloading) {
-                fetch('/tasks').then(res => res.json()).then(tasks => {
-                    const queuedTasks = tasks.filter(t => t.status === 'queued');
-                    const inProgressTasks = tasks.filter(t => t.status === 'in-progress');
-
-                    // 如果没有进行中的任务但有排队的任务，启动下载
-                    if (inProgressTasks.length === 0 && queuedTasks.length > 0) {
-                        startDirectDownload(queuedTasks[0].book_id);
-                    }
-                }).catch(console.error);
-            }
+            // 更新当前下载任务ID用于UI显示
+            fetch('/tasks').then(res => res.json()).then(tasks => {
+                const inProgressTasks = tasks.filter(t => t.status === 'in-progress');
+                currentDownloadId = inProgressTasks.length > 0 ? inProgressTasks[0].book_id : null;
+            }).catch(console.error);
         }, 2000);
 
         // 添加一些交互效果
@@ -1016,16 +900,12 @@ def root():
 @app.get("/enqueue")
 def enqueue(book_id: str):
     """添加到下载队列"""
+    from datetime import datetime
+
     # 如果已有任务在队列或处理中
     if STATUS.get(book_id) in ("queued", "in-progress"):
         return {"message": "已在队列", "status": STATUS[book_id]}
 
-    # 如果任务已完成，重新设置为排队状态
-    if STATUS.get(book_id) == "done":
-        STATUS[book_id] = "queued"
-        TASK_QUEUE.put(book_id)
-        return {"message": "重新添加到下载队列", "status": "queued"}
-
     # 获取书籍信息并设置名称
     try:
         name, _, _ = get_book_info(book_id, get_headers())
@@ -1034,6 +914,15 @@ def enqueue(book_id: str):
     except:
         NAMES[book_id] = f"小说_{book_id}"
 
+    # 记录任务详细信息
+    current_time = datetime.now().strftime("%Y-%m-%d %H:%M:%S")
+    TASK_DETAILS[book_id] = {
+        "add_time": current_time,
+        "start_time": None,
+        "complete_time": None,
+        "name": NAMES[book_id]
+    }
+
     TASK_QUEUE.put(book_id)
     STATUS[book_id] = "queued"
     return {"message": "已添加到下载队列", "status": "queued"}
@@ -1053,7 +942,22 @@ def task_status(book_id: str):
 @app.get("/tasks")
 def tasks():
     """获取所有任务"""
-    return [{"book_id": bid, "status": status, "name": NAMES.get(bid, "")} for bid, status in STATUS.items()]
+    task_list = []
+    for book_id, status in STATUS.items():
+        task_detail = TASK_DETAILS.get(book_id, {})
+        task = {
+            "book_id": book_id,
+            "name": NAMES.get(book_id, book_id),
+            "status": status,
+            "add_time": task_detail.get("add_time", "未知"),
+            "start_time": task_detail.get("start_time"),
+            "complete_time": task_detail.get("complete_time")
+        }
+        task_list.append(task)
+
+    # 按添加时间排序，最新的在前面
+    task_list.sort(key=lambda x: x["add_time"], reverse=True)
+    return task_list
 
 @app.get("/search")
 def search(name: str = ""):