feat(printer): 实现打印机任务WebSocket实时推送功能

- 新增PrinterTaskPushService接口及实现，负责任务推送逻辑
- 在PrinterServiceImpl中集成WebSocket推送，在任务创建和审核通过时主动推送
- 新增WebSocket配置类和处理器，支持打印机通过WebSocket连接接收任务
- 实现连接管理器，维护打印机在线状态并支持心跳保活
- 添加相关模型类如WsMessage、WsMessageType等，规范通信协议
- 在PrinterMapper中增加查询待处理任务列表的方法
- 完善异常处理和日志记录，确保推送可靠性

src/main/java/com/ycwl/basic/service/printer/PrinterTaskPushService.java

@@ -0,0 +1,28 @@
+package com.ycwl.basic.service.printer;
+
+import com.ycwl.basic.model.printer.resp.PrintTaskResp;
+
+import java.util.List;
+
+/**
+ * 打印机任务推送服务
+ */
+public interface PrinterTaskPushService {
+
+    /**
+     * 推送任务到打印机
+     *
+     * @param printerId 打印机ID
+     * @param taskId    任务ID
+     * @return 是否推送成功
+     */
+    boolean pushTaskToPrinter(Integer printerId, Integer taskId);
+
+    /**
+     * 获取打印机的待处理任务列表
+     *
+     * @param printerId 打印机ID
+     * @return 待处理任务列表
+     */
+    List<PrintTaskResp> getPendingTasksByPrinterId(Integer printerId);
+}

src/main/java/com/ycwl/basic/service/printer/impl/PrinterServiceImpl.java

@@ -67,6 +67,7 @@ import com.ycwl.basic.repository.ScenicRepository;
 import com.ycwl.basic.service.mobile.WxPayService;
 import com.ycwl.basic.service.pc.FaceService;
 import com.ycwl.basic.service.printer.PrinterService;
+import com.ycwl.basic.service.printer.PrinterTaskPushService;
 import com.ycwl.basic.storage.StorageFactory;
 import com.ycwl.basic.storage.adapters.IStorageAdapter;
 import com.ycwl.basic.utils.ApiResponse;
@@ -140,6 +141,8 @@ public class PrinterServiceImpl implements PrinterService {
     private FaceService faceService;
     @Autowired
     private DeviceRepository deviceRepository;
+    @Autowired
+    private PrinterTaskPushService taskPushService;
 
     // 用于优先打印的线程池,核心线程数根据实际情况调整
     private final ExecutorService preferPrintExecutor = Executors.newFixedThreadPool(
@@ -961,6 +964,17 @@ public class PrinterServiceImpl implements PrinterService {
                 task.setCreateTime(new Date());
                 task.setUpdateTime(new Date());
                 printTaskMapper.insertTask(task);
+
+                // ========== WebSocket 推送任务 ==========
+                // 只推送立即可处理的任务（status=0），待审核任务（status=4）等审核通过后再推送
+                if (initialStatus == TASK_STATUS_PENDING) {
+                    try {
+                        taskPushService.pushTaskToPrinter(printer.getId(), task.getId());
+                    } catch (Exception e) {
+                        log.error("推送任务失败: printerId={}, taskId={}", printer.getId(), task.getId(), e);
+                        // 推送失败不影响任务创建，任务会通过 HTTP 轮询获取
+                    }
+                }
             }
         });
     }
@@ -1001,7 +1015,21 @@ public class PrinterServiceImpl implements PrinterService {
             return 0;
         }
         // 将状态从4（待审核）改为0（待处理）
-        return printTaskMapper.batchUpdateStatus(taskIds, TASK_STATUS_PENDING);
+        int count = printTaskMapper.batchUpdateStatus(taskIds, TASK_STATUS_PENDING);
+
+        // ========== WebSocket 推送审核通过的任务 ==========
+        for (Integer taskId : taskIds) {
+            try {
+                PrintTaskEntity task = printTaskMapper.selectById(taskId);
+                if (task != null && task.getPrinterId() != null) {
+                    taskPushService.pushTaskToPrinter(task.getPrinterId(), taskId);
+                }
+            } catch (Exception e) {
+                log.error("推送审核任务失败: taskId={}", taskId, e);
+            }
+        }
+
+        return count;
     }
 
     /**

src/main/java/com/ycwl/basic/service/printer/impl/PrinterTaskPushServiceImpl.java

@@ -0,0 +1,110 @@
+package com.ycwl.basic.service.printer.impl;
+
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.ycwl.basic.mapper.PrinterMapper;
+import com.ycwl.basic.model.pc.printer.entity.PrintTaskEntity;
+import com.ycwl.basic.model.printer.resp.PrintTaskResp;
+import com.ycwl.basic.service.printer.PrinterTaskPushService;
+import com.ycwl.basic.websocket.manager.PrinterConnectionManager;
+import com.ycwl.basic.websocket.model.WsMessage;
+import com.ycwl.basic.websocket.model.WsMessageType;
+import lombok.extern.slf4j.Slf4j;
+import org.springframework.beans.BeanUtils;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.stereotype.Service;
+import org.springframework.web.socket.TextMessage;
+import org.springframework.web.socket.WebSocketSession;
+
+import java.util.List;
+
+/**
+ * 打印机任务推送服务实现
+ */
+@Slf4j
+@Service
+public class PrinterTaskPushServiceImpl implements PrinterTaskPushService {
+
+    private static final int TASK_STATUS_PENDING = 0;
+    private static final int TASK_STATUS_PROCESSING = 3;
+
+    @Autowired
+    private PrinterMapper printerMapper;
+
+    @Autowired
+    private PrinterConnectionManager connectionManager;
+
+    @Autowired
+    private ObjectMapper objectMapper;
+
+    @Override
+    public boolean pushTaskToPrinter(Integer printerId, Integer taskId) {
+        try {
+            // 1. 检查打印机是否在线
+            if (!connectionManager.isOnline(printerId)) {
+                log.debug("打印机不在线,跳过推送: printerId={}, taskId={}", printerId, taskId);
+                return false;
+            }
+
+            // 2. 获取 WebSocket 连接
+            WebSocketSession session = connectionManager.getSession(printerId);
+            if (session == null || !session.isOpen()) {
+                log.warn("打印机连接不可用: printerId={}, taskId={}", printerId, taskId);
+                return false;
+            }
+
+            // 3. 执行 CAS 操作,确保任务只被推送一次
+            int updatedRows = printerMapper.compareAndSetTaskStatus(
+                    taskId, TASK_STATUS_PENDING, TASK_STATUS_PROCESSING
+            );
+
+            if (updatedRows != 1) {
+                log.debug("任务已被获取,跳过推送: printerId={}, taskId={}", printerId, taskId);
+                return false;
+            }
+
+            // 4. 查询任务详情
+            PrintTaskEntity taskEntity = printerMapper.getTaskById(taskId);
+            if (taskEntity == null) {
+                log.error("任务不存在: taskId={}", taskId);
+                return false;
+            }
+
+            // 5. 转换为 PrintTaskResp
+            PrintTaskResp task = new PrintTaskResp();
+            BeanUtils.copyProperties(taskEntity, task);
+            task.setStatus(TASK_STATUS_PROCESSING);
+
+            // 6. 通过 WebSocket 推送任务
+            WsMessage<PrintTaskResp> message = WsMessage.create(WsMessageType.TASK_PUSH, task);
+            String json = objectMapper.writeValueAsString(message);
+            session.sendMessage(new TextMessage(json));
+
+            log.info("任务推送成功: printerId={}, taskId={}", printerId, taskId);
+            return true;
+
+        } catch (Exception e) {
+            log.error("任务推送失败: printerId={}, taskId={}", printerId, taskId, e);
+            // 推送失败时,恢复任务状态为待处理
+            try {
+                printerMapper.compareAndSetTaskStatus(
+                        taskId, TASK_STATUS_PROCESSING, TASK_STATUS_PENDING
+                );
+            } catch (Exception ex) {
+                log.error("恢复任务状态失败: taskId={}", taskId, ex);
+            }
+            return false;
+        }
+    }
+
+    @Override
+    public List<PrintTaskResp> getPendingTasksByPrinterId(Integer printerId) {
+        // 直接查询该打印机所有待处理任务 (status=0)，最多返回 100 个
+        List<PrintTaskResp> tasks = printerMapper.listPendingTasksByPrinterId(printerId);
+
+        if (tasks.size() >= 100) {
+            log.warn("待处理任务过多,已达上限: printerId={}, count={}", printerId, tasks.size());
+        }
+
+        return tasks;
+    }
+}