diff --git a/tests/CMakeLists.txt b/tests/CMakeLists.txt
index 4d2e498..59052db 100644
--- a/tests/CMakeLists.txt
+++ b/tests/CMakeLists.txt
@@ -1,5 +1,9 @@
-# GoogleTest配置
+cmake_minimum_required(VERSION 3.10.0)
+project(CppGenerate_test)
 include(FetchContent)
+if (MSVC)
+    add_compile_options(/utf-8)
+endif()
 FetchContent_Declare(
   googletest
   URL https://github.com/google/googletest/archive/03597a01ee50ed33e9dfd640b249b4be3799d395.zip
@@ -7,24 +11,15 @@ FetchContent_Declare(
 # For Windows: Prevent overriding the parent project's compiler/linker settings
 set(gtest_force_shared_crt ON CACHE BOOL "" FORCE)
 FetchContent_MakeAvailable(googletest)
+set(CMAKE_CXX_STANDARD 14)
+set(CMAKE_CXX_STANDARD_REQUIRED ON)
+include_directories(${CMAKE_CURRENT_SOURCE_DIR}/../include)
 
-# 包含目录
-include_directories(${CMAKE_SOURCE_DIR}/src)
-include_directories(${CMAKE_SOURCE_DIR}/include)
-
-# 启用测试
+include(CTest)
 enable_testing()
 
-# 添加alert_manager的单元测试
-add_executable(test_alert_manager test_alert_manager.cpp ../src/alert_manager.cpp)
+add_executable(CppGenerate_test test_alert_manager.cpp ../src/alert_manager.cpp)
 
-# 设置UTF-8编码支持
-if(MSVC)
-    target_compile_options(test_alert_manager PRIVATE /utf-8)
-endif()
-
-target_link_libraries(test_alert_manager gtest gmock gtest_main)
-
-# 注册测试
+target_link_libraries(CppGenerate_test gtest gmock gtest_main)
 include(GoogleTest)
-gtest_discover_tests(test_alert_manager)
\ No newline at end of file
+gtest_discover_tests(CppGenerate_test)
\ No newline at end of file
diff --git a/tests/test_alert_manager.cpp b/tests/test_alert_manager.cpp
index 5bc247a..1551aff 100644
--- a/tests/test_alert_manager.cpp
+++ b/tests/test_alert_manager.cpp
@@ -3,265 +3,508 @@
 #include <vector>
 #include <string>
 
-// Mock for time to ensure deterministic tests
-static uint32_t mock_timestamp = 1640995200; // 2022-01-01 00:00:00 UTC
+using namespace std;
 
-class MockTime { 
-public:
-    static uint32_t getTimestamp() { return mock_timestamp; }
-    static void setTimestamp(uint32_t t) { mock_timestamp = t; }
-};
+// Mock time function for deterministic testing
+uint32_t mock_timestamp = 1000;
+uint32_t getMockTimestamp() { return mock_timestamp; }
 
-// Helper function to compare AlertInfo
-bool operator==(const AlertInfo& a, const AlertInfo& b) {
-    return a.type == b.type &&
-           a.status == b.status &&
-           a.trigger_time == b.trigger_time &&
-           a.acknowledge_time == b.acknowledge_time &&
-           a.resolve_time == b.resolve_time &&
-           a.description == b.description;
-}
+// Override the real time function with mock
+uint32_t getCurrentTime() { return getMockTimestamp(); }
 
-// Test fixture
+// Test fixture for AlertManager
 class AlertManagerTest : public ::testing::Test {
 protected:
-    AlertManager manager;
+    AlertManager alert_manager;
 
     void SetUp() override {
-        mock_timestamp = 1640995200;
-        manager.initialize();
+        // Reset mock timestamp
+        mock_timestamp = 1000;
+        alert_manager.initialize();
     }
 
-    void TearDown() override {
-        manager.clearHistory();
+    void advanceTime(uint32_t seconds) {
+        mock_timestamp += seconds;
     }
 };
 
-TEST_F(AlertManagerTest, testAlertManagerDefaultInitialization) {
-    EXPECT_FLOAT_EQ(manager.getAltitudeThresholds().first, 100.0f);
-    EXPECT_FLOAT_EQ(manager.getAltitudeThresholds().second, -50.0f);
-    EXPECT_TRUE(manager.getActiveAlerts().empty());
-    EXPECT_TRUE(manager.getAlertHistory(10).empty());
+// Test checkAltitudeAlert - Normal Input
+TEST_F(AlertManagerTest, testCheckAltitudeAlertNormalInput) {
+    // Arrange
+    float altitude = 90.0f; // Below upper threshold
+    
+    // Act
+    alert_manager.checkAltitudeAlert(altitude, getMockTimestamp());
+    
+    // Assert
+    EXPECT_FALSE(alert_manager.hasActiveAlerts());
 }
 
-TEST_F(AlertManagerTest, testInitialize) {
-    // No direct output assertion, but verify initialization logic
-    // This is tested implicitly via constructor
-    EXPECT_NO_FATAL_FAILURE(manager.initialize());
+// Test checkAltitudeAlert - Upper Threshold Exceeded
+TEST_F(AlertManagerTest, testCheckAltitudeAlertUpperThresholdExceeded) {
+    // Arrange
+    float altitude = 105.0f; // Above upper threshold
+    
+    // Act
+    alert_manager.checkAltitudeAlert(altitude, getMockTimestamp());
+    
+    // Assert
+    EXPECT_TRUE(alert_manager.hasActiveAlerts());
+    auto active_alerts = alert_manager.getActiveAlerts();
+    EXPECT_EQ(active_alerts.size(), 1);
+    EXPECT_EQ(active_alerts[0].type, AlertType::ALTITUDE_UPPER);
+    EXPECT_EQ(active_alerts[0].status, AlertStatus::ACTIVE);
 }
 
-TEST_F(AlertManagerTest, testCheckAltitudeAlertNormal) {
-    mock_timestamp = 1640995200;
-    manager.checkAltitudeAlert(105.0f, mock_timestamp);
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_EQ(alerts.size(), 1);
-    EXPECT_EQ(alerts[0].type, AlertType::ALTITUDE_UPPER);
-    EXPECT_EQ(alerts[0].status, AlertStatus::ACTIVE);
-    EXPECT_EQ(alerts[0].trigger_time, mock_timestamp);
+// Test checkAltitudeAlert - Lower Threshold Exceeded
+TEST_F(AlertManagerTest, testCheckAltitudeAlertLowerThresholdExceeded) {
+    // Arrange
+    float altitude = -60.0f; // Below lower threshold
+    
+    // Act
+    alert_manager.checkAltitudeAlert(altitude, getMockTimestamp());
+    
+    // Assert
+    EXPECT_TRUE(alert_manager.hasActiveAlerts());
+    auto active_alerts = alert_manager.getActiveAlerts();
+    EXPECT_EQ(active_alerts.size(), 1);
+    EXPECT_EQ(active_alerts[0].type, AlertType::ALTITUDE_LOWER);
+    EXPECT_EQ(active_alerts[0].status, AlertStatus::ACTIVE);
 }
 
-TEST_F(AlertManagerTest, testCheckAltitudeAlertBelowLower) {
-    mock_timestamp = 1640995200;
-    manager.checkAltitudeAlert(-55.0f, mock_timestamp);
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_EQ(alerts.size(), 1);
-    EXPECT_EQ(alerts[0].type, AlertType::ALTITUDE_LOWER);
-    EXPECT_EQ(alerts[0].status, AlertStatus::ACTIVE);
+// Test checkAltitudeAlert - Recovery from Upper Threshold
+TEST_F(AlertManagerTest, testCheckAltitudeAlertRecoveryFromUpper) {
+    // Arrange
+    float altitude_high = 105.0f;
+    float altitude_low = 90.0f;
+    
+    // Act
+    alert_manager.checkAltitudeAlert(altitude_high, getMockTimestamp());
+    alert_manager.checkAltitudeAlert(altitude_low, getMockTimestamp());
+    
+    // Assert
+    EXPECT_FALSE(alert_manager.hasActiveAlerts());
 }
 
-TEST_F(AlertManagerTest, testCheckAltitudeAlertResetWhenNormal) {
-    mock_timestamp = 1640995200;
-    manager.checkAltitudeAlert(105.0f, mock_timestamp); // Trigger upper
-    mock_timestamp = 1640995201;
-    manager.checkAltitudeAlert(90.0f, mock_timestamp); // Reset
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_TRUE(alerts.empty());
+// Test checkAltitudeAlert - Recovery from Lower Threshold
+TEST_F(AlertManagerTest, testCheckAltitudeAlertRecoveryFromLower) {
+    // Arrange
+    float altitude_low = -60.0f;
+    float altitude_high = -40.0f;
+    
+    // Act
+    alert_manager.checkAltitudeAlert(altitude_low, getMockTimestamp());
+    alert_manager.checkAltitudeAlert(altitude_high, getMockTimestamp());
+    
+    // Assert
+    EXPECT_FALSE(alert_manager.hasActiveAlerts());
 }
 
-TEST_F(AlertManagerTest, testSetAltitudeThresholdsValid) {
-    manager.setAltitudeThresholds(200.0f, -100.0f);
-    auto thresholds = manager.getAltitudeThresholds();
-    EXPECT_FLOAT_EQ(thresholds.first, 200.0f);
-    EXPECT_FLOAT_EQ(thresholds.second, -100.0f);
+// Test setAltitudeThresholds - Valid Thresholds
+TEST_F(AlertManagerTest, testSetAltitudeThresholdsValidThresholds) {
+    // Arrange
+    float upper = 150.0f;
+    float lower = -100.0f;
+    
+    // Act
+    alert_manager.setAltitudeThresholds(upper, lower);
+    
+    // Assert
+    EXPECT_EQ(alert_manager.getAltitudeThresholds().first, upper);
+    EXPECT_EQ(alert_manager.getAltitudeThresholds().second, lower);
 }
 
-TEST_F(AlertManagerTest, testSetAltitudeThresholdsInvalid) {
-    EXPECT_NO_FATAL_FAILURE(manager.setAltitudeThresholds(50.0f, 100.0f));
-    // Should print error, but no crash
-    EXPECT_FLOAT_EQ(manager.getAltitudeThresholds().first, 100.0f);
-    EXPECT_FLOAT_EQ(manager.getAltitudeThresholds().second, -50.0f);
+// Test setAltitudeThresholds - Invalid Thresholds (upper <= lower)
+TEST_F(AlertManagerTest, testSetAltitudeThresholdsInvalidThresholds) {
+    // Arrange
+    float upper = 100.0f;
+    float lower = 100.0f;
+    
+    // Act & Assert
+    EXPECT_NO_THROW(alert_manager.setAltitudeThresholds(upper, lower));
+    // Error message should be printed but not throw exception
 }
 
-TEST_F(AlertManagerTest, testTriggerSensorFailure) {
-    mock_timestamp = 1640995200;
-    manager.triggerSensorFailure(mock_timestamp);
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_EQ(alerts.size(), 1);
-    EXPECT_EQ(alerts[0].type, AlertType::SENSOR_FAILURE);
-    EXPECT_EQ(alerts[0].status, AlertStatus::ACTIVE);
-    EXPECT_EQ(alerts[0].trigger_time, mock_timestamp);
+// Test triggerSensorFailure - Normal Operation
+TEST_F(AlertManagerTest, testTriggerSensorFailureNormalOperation) {
+    // Arrange
+    uint32_t timestamp = getMockTimestamp();
+    
+    // Act
+    alert_manager.triggerSensorFailure(timestamp);
+    
+    // Assert
+    EXPECT_TRUE(alert_manager.hasActiveAlerts());
+    auto active_alerts = alert_manager.getActiveAlerts();
+    EXPECT_EQ(active_alerts.size(), 1);
+    EXPECT_EQ(active_alerts[0].type, AlertType::SENSOR_FAILURE);
+    EXPECT_EQ(active_alerts[0].status, AlertStatus::ACTIVE);
 }
 
-TEST_F(AlertManagerTest, testTriggerLowBattery) {
-    mock_timestamp = 1640995200;
-    manager.triggerLowBattery(mock_timestamp, 15.0f);
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_EQ(alerts.size(), 1);
-    EXPECT_EQ(alerts[0].type, AlertType::LOW_BATTERY);
-    EXPECT_EQ(alerts[0].status, AlertStatus::ACTIVE);
-    EXPECT_NE(alerts[0].description.find("15.0%"), std::string::npos);
+// Test triggerLowBattery - Normal Operation
+TEST_F(AlertManagerTest, testTriggerLowBatteryNormalOperation) {
+    // Arrange
+    uint32_t timestamp = getMockTimestamp();
+    float battery_level = 15.0f;
+    
+    // Act
+    alert_manager.triggerLowBattery(timestamp, battery_level);
+    
+    // Assert
+    EXPECT_TRUE(alert_manager.hasActiveAlerts());
+    auto active_alerts = alert_manager.getActiveAlerts();
+    EXPECT_EQ(active_alerts.size(), 1);
+    EXPECT_EQ(active_alerts[0].type, AlertType::LOW_BATTERY);
+    EXPECT_EQ(active_alerts[0].status, AlertStatus::ACTIVE);
+    EXPECT_NE(active_alerts[0].description.find("低电量警告"), string::npos);
 }
 
-TEST_F(AlertManagerTest, testTriggerCommunicationError) {
-    mock_timestamp = 1640995200;
-    manager.triggerCommunicationError(mock_timestamp);
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_EQ(alerts.size(), 1);
-    EXPECT_EQ(alerts[0].type, AlertType::COMMUNICATION_ERROR);
-    EXPECT_EQ(alerts[0].status, AlertStatus::ACTIVE);
+// Test triggerCommunicationError - Normal Operation
+TEST_F(AlertManagerTest, testTriggerCommunicationErrorNormalOperation) {
+    // Arrange
+    uint32_t timestamp = getMockTimestamp();
+    
+    // Act
+    alert_manager.triggerCommunicationError(timestamp);
+    
+    // Assert
+    EXPECT_TRUE(alert_manager.hasActiveAlerts());
+    auto active_alerts = alert_manager.getActiveAlerts();
+    EXPECT_EQ(active_alerts.size(), 1);
+    EXPECT_EQ(active_alerts[0].type, AlertType::COMMUNICATION_ERROR);
+    EXPECT_EQ(active_alerts[0].status, AlertStatus::ACTIVE);
 }
 
-TEST_F(AlertManagerTest, testAcknowledgeAllAlerts) {
-    mock_timestamp = 1640995200;
-    manager.triggerSensorFailure(mock_timestamp);
-    manager.triggerLowBattery(mock_timestamp + 1, 10.0f);
-    mock_timestamp = 1640995202;
-    manager.acknowledgeAllAlerts(mock_timestamp);
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_TRUE(alerts.empty());
-    EXPECT_EQ(alerts.size(), 0);
+// Test acknowledgeAllAlerts - Acknowledge All Active Alerts
+TEST_F(AlertManagerTest, testAcknowledgeAllAlertsAcknowledgeAllActive) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    alert_manager.triggerLowBattery(getMockTimestamp(), 10.0f);
+    
+    // Act
+    alert_manager.acknowledgeAllAlerts(getMockTimestamp());
+    
+    // Assert
+    EXPECT_FALSE(alert_manager.hasUnacknowledgedAlerts());
+    auto active_alerts = alert_manager.getActiveAlerts();
+    EXPECT_EQ(active_alerts.size(), 2);
+    EXPECT_EQ(active_alerts[0].status, AlertStatus::ACKNOWLEDGED);
+    EXPECT_EQ(active_alerts[1].status, AlertStatus::ACKNOWLEDGED);
 }
 
-TEST_F(AlertManagerTest, testAcknowledgeAlert) {
-    mock_timestamp = 1640995200;
-    manager.triggerSensorFailure(mock_timestamp);
-    mock_timestamp = 1640995201;
-    manager.acknowledgeAlert(AlertType::SENSOR_FAILURE, mock_timestamp);
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_TRUE(alerts.empty());
+// Test acknowledgeAlert - Acknowledge Specific Alert
+TEST_F(AlertManagerTest, testAcknowledgeAlertAcknowledgeSpecific) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    
+    // Act
+    alert_manager.acknowledgeAlert(AlertType::SENSOR_FAILURE, getMockTimestamp());
+    
+    // Assert
+    EXPECT_FALSE(alert_manager.hasUnacknowledgedAlerts());
+    auto active_alerts = alert_manager.getActiveAlerts();
+    EXPECT_EQ(active_alerts.size(), 1);
+    EXPECT_EQ(active_alerts[0].status, AlertStatus::ACKNOWLEDGED);
 }
 
-TEST_F(AlertManagerTest, testResetAlert) {
-    mock_timestamp = 1640995200;
-    manager.triggerSensorFailure(mock_timestamp);
-    manager.resetAlert(AlertType::SENSOR_FAILURE);
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_TRUE(alerts.empty());
+// Test acknowledgeAlert - Non-Existing Alert
+TEST_F(AlertManagerTest, testAcknowledgeAlertNonExistingAlert) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    
+    // Act
+    alert_manager.acknowledgeAlert(AlertType::COMMUNICATION_ERROR, getMockTimestamp());
+    
+    // Assert
+    EXPECT_TRUE(alert_manager.hasActiveAlerts());
+    auto active_alerts = alert_manager.getActiveAlerts();
+    EXPECT_EQ(active_alerts.size(), 1);
+    EXPECT_EQ(active_alerts[0].status, AlertStatus::ACTIVE);
 }
 
-TEST_F(AlertManagerTest, testResetAllAlerts) {
-    mock_timestamp = 1640995200;
-    manager.triggerSensorFailure(mock_timestamp);
-    manager.triggerLowBattery(mock_timestamp + 1, 10.0f);
-    manager.resetAllAlerts();
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_TRUE(alerts.empty());
+// Test resetAlert - Reset Existing Alert
+TEST_F(AlertManagerTest, testResetAlertResetExisting) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    
+    // Act
+    alert_manager.resetAlert(AlertType::SENSOR_FAILURE);
+    
+    // Assert
+    EXPECT_FALSE(alert_manager.hasActiveAlerts());
+    EXPECT_FALSE(alert_manager.hasUnacknowledgedAlerts());
 }
 
-TEST_F(AlertManagerTest, testHasActiveAlerts) {
-    EXPECT_FALSE(manager.hasActiveAlerts());
-    mock_timestamp = 1640995200;
-    manager.triggerSensorFailure(mock_timestamp);
-    EXPECT_TRUE(manager.hasActiveAlerts());
+// Test resetAlert - Reset Non-Existing Alert
+TEST_F(AlertManagerTest, testResetAlertResetNonExisting) {
+    // Arrange
+    
+    // Act
+    alert_manager.resetAlert(AlertType::COMMUNICATION_ERROR);
+    
+    // Assert
+    EXPECT_FALSE(alert_manager.hasActiveAlerts());
+    EXPECT_FALSE(alert_manager.hasUnacknowledgedAlerts());
 }
 
-TEST_F(AlertManagerTest, testHasUnacknowledgedAlerts) {
-    EXPECT_FALSE(manager.hasUnacknowledgedAlerts());
-    mock_timestamp = 1640995200;
-    manager.triggerSensorFailure(mock_timestamp);
-    EXPECT_TRUE(manager.hasUnacknowledgedAlerts());
-    manager.acknowledgeAllAlerts(mock_timestamp + 1);
-    EXPECT_FALSE(manager.hasUnacknowledgedAlerts());
+// Test resetAllAlerts - Reset All Alerts
+TEST_F(AlertManagerTest, testResetAllAlertsResetAll) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    alert_manager.triggerLowBattery(getMockTimestamp(), 10.0f);
+    
+    // Act
+    alert_manager.resetAllAlerts();
+    
+    // Assert
+    EXPECT_FALSE(alert_manager.hasActiveAlerts());
+    EXPECT_FALSE(alert_manager.hasUnacknowledgedAlerts());
 }
 
-TEST_F(AlertManagerTest, testGetActiveAlerts) {
-    mock_timestamp = 1640995200;
-    manager.triggerSensorFailure(mock_timestamp);
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_EQ(alerts.size(), 1);
-    EXPECT_EQ(alerts[0].type, AlertType::SENSOR_FAILURE);
+// Test hasActiveAlerts - No Active Alerts
+TEST_F(AlertManagerTest, testHasActiveAlertsNoActiveAlerts) {
+    // Arrange
+    
+    // Act
+    bool result = alert_manager.hasActiveAlerts();
+    
+    // Assert
+    EXPECT_FALSE(result);
 }
 
-TEST_F(AlertManagerTest, testGetAlertHistoryMaxCount) {
-    mock_timestamp = 1640995200;
-    for (int i = 0; i < 15; ++i) {
-        manager.triggerSensorFailure(mock_timestamp + i);
-    }
-    auto history = manager.getAlertHistory(10);
-    EXPECT_EQ(history.size(), 10);
+// Test hasActiveAlerts - With Active Alerts
+TEST_F(AlertManagerTest, testHasActiveAlertsWithActiveAlerts) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    
+    // Act
+    bool result = alert_manager.hasActiveAlerts();
+    
+    // Assert
+    EXPECT_TRUE(result);
 }
 
-TEST_F(AlertManagerTest, testGetStatusDescriptionNoAlerts) {
-    std::string desc = manager.getStatusDescription();
-    EXPECT_EQ(desc, "系统状态：正常");
+// Test hasUnacknowledgedAlerts - No Unacknowledged Alerts
+TEST_F(AlertManagerTest, testHasUnacknowledgedAlertsNoUnacknowledgedAlerts) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    alert_manager.acknowledgeAllAlerts(getMockTimestamp());
+    
+    // Act
+    bool result = alert_manager.hasUnacknowledgedAlerts();
+    
+    // Assert
+    EXPECT_FALSE(result);
 }
 
-TEST_F(AlertManagerTest, testGetStatusDescriptionWithAlerts) {
-    mock_timestamp = 1640995200;
-    manager.triggerSensorFailure(mock_timestamp);
-    std::string desc = manager.getStatusDescription();
-    EXPECT_NE(desc.find("有1个活动预警"), std::string::npos);
-    EXPECT_NE(desc.find("传感器故障"), std::string::npos);
+// Test hasUnacknowledgedAlerts - With Unacknowledged Alerts
+TEST_F(AlertManagerTest, testHasUnacknowledgedAlertsWithUnacknowledgedAlerts) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    
+    // Act
+    bool result = alert_manager.hasUnacknowledgedAlerts();
+    
+    // Assert
+    EXPECT_TRUE(result);
 }
 
-TEST_F(AlertManagerTest, testClearHistory) {
-    mock_timestamp = 1640995200;
-    manager.triggerSensorFailure(mock_timestamp);
-    manager.clearHistory();
-    EXPECT_TRUE(manager.getAlertHistory(10).empty());
+// Test getActiveAlerts - Empty List
+TEST_F(AlertManagerTest, testGetActiveAlertsEmptyList) {
+    // Arrange
+    
+    // Act
+    vector<AlertInfo> result = alert_manager.getActiveAlerts();
+    
+    // Assert
+    EXPECT_EQ(result.size(), 0);
 }
 
-TEST_F(AlertManagerTest, testAddToHistoryLimit) {
-    mock_timestamp = 1640995200;
-    for (int i = 0; i < 100; ++i) {
-        manager.triggerSensorFailure(mock_timestamp + i);
-    }
-    auto history = manager.getAlertHistory(10);
-    EXPECT_EQ(history.size(), 10);
+// Test getActiveAlerts - With Active Alerts
+TEST_F(AlertManagerTest, testGetActiveAlertsWithActiveAlerts) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    
+    // Act
+    vector<AlertInfo> result = alert_manager.getActiveAlerts();
+    
+    // Assert
+    EXPECT_EQ(result.size(), 1);
+    EXPECT_EQ(result[0].type, AlertType::SENSOR_FAILURE);
+    EXPECT_EQ(result[0].status, AlertStatus::ACTIVE);
 }
 
-TEST_F(AlertManagerTest, testTriggerAlert) {
-    mock_timestamp = 1640995200;
-    manager.triggerAlert(AlertType::SENSOR_FAILURE, mock_timestamp, "Test alert");
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_EQ(alerts.size(), 1);
-    EXPECT_EQ(alerts[0].description, "Test alert");
+// Test getAlertHistory - Max Count Greater Than History Size
+TEST_F(AlertManagerTest, testGetAlertHistoryMaxCountGreaterThanHistorySize) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    alert_manager.triggerLowBattery(getMockTimestamp(), 10.0f);
+    
+    // Act
+    vector<AlertInfo> result = alert_manager.getAlertHistory(5);
+    
+    // Assert
+    EXPECT_EQ(result.size(), 2);
 }
 
-TEST_F(AlertManagerTest, testUpdateAlertStatusAcknowledged) {
-    mock_timestamp = 1640995200;
-    manager.triggerSensorFailure(mock_timestamp);
-    mock_timestamp = 1640995201;
-    manager.updateAlertStatus(AlertType::SENSOR_FAILURE, AlertStatus::ACKNOWLEDGED, mock_timestamp);
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_TRUE(alerts.empty());
+// Test getAlertHistory - Max Count Less Than History Size
+TEST_F(AlertManagerTest, testGetAlertHistoryMaxCountLessThanHistorySize) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    alert_manager.triggerLowBattery(getMockTimestamp(), 10.0f);
+    alert_manager.triggerCommunicationError(getMockTimestamp());
+    
+    // Act
+    vector<AlertInfo> result = alert_manager.getAlertHistory(2);
+    
+    // Assert
+    EXPECT_EQ(result.size(), 2);
+    EXPECT_EQ(result[0].type, AlertType::COMMUNICATION_ERROR);
+    EXPECT_EQ(result[1].type, AlertType::LOW_BATTERY);
 }
 
-TEST_F(AlertManagerTest, testUpdateAlertStatusResolved) {
-    mock_timestamp = 1640995200;
-    manager.triggerSensorFailure(mock_timestamp);
-    mock_timestamp = 1640995201;
-    manager.updateAlertStatus(AlertType::SENSOR_FAILURE, AlertStatus::RESOLVED, mock_timestamp);
-    auto alerts = manager.getActiveAlerts();
-    EXPECT_TRUE(alerts.empty());
+// Test getStatusDescription - No Active Alerts
+TEST_F(AlertManagerTest, testGetStatusDescriptionNoActiveAlerts) {
+    // Arrange
+    
+    // Act
+    string result = alert_manager.getStatusDescription();
+    
+    // Assert
+    EXPECT_EQ(result, "系统状态：正常");
 }
 
-TEST_F(AlertManagerTest, testGetAlertTypeName) {
-    EXPECT_EQ(manager.getAlertTypeName(AlertType::ALTITUDE_UPPER), "高度上限预警");
-    EXPECT_EQ(manager.getAlertTypeName(AlertType::NONE), "无");
-    EXPECT_EQ(manager.getAlertTypeName(static_cast<AlertType>(99)), "未知预警");
+// Test getStatusDescription - With Active Alerts
+TEST_F(AlertManagerTest, testGetStatusDescriptionWithActiveAlerts) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    
+    // Act
+    string result = alert_manager.getStatusDescription();
+    
+    // Assert
+    EXPECT_NE(result.find("系统状态：有1个活动预警"), string::npos);
+    EXPECT_NE(result.find("传感器故障"), string::npos);
 }
 
-TEST_F(AlertManagerTest, testGetAlertStatusName) {
-    EXPECT_EQ(manager.getAlertStatusName(AlertStatus::ACTIVE), "预警中");
-    EXPECT_EQ(manager.getAlertStatusName(AlertStatus::INACTIVE), "未激活");
-    EXPECT_EQ(manager.getAlertStatusName(static_cast<AlertStatus>(99)), "未知状态");
+// Test clearHistory - Clear All History
+TEST_F(AlertManagerTest, testClearHistoryClearAll) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    alert_manager.triggerLowBattery(getMockTimestamp(), 10.0f);
+    
+    // Act
+    alert_manager.clearHistory();
+    
+    // Assert
+    EXPECT_EQ(alert_manager.getAlertHistory(10).size(), 0);
 }
 
-TEST_F(AlertManagerTest, testDestructorDoesNotCrash) {
-    // Verify destructor doesn't throw or crash
-    EXPECT_NO_FATAL_FAILURE({
-        AlertManager* mgr = new AlertManager();
-        delete mgr;
-    });
+// Test addToHistory - Add to History
+TEST_F(AlertManagerTest, testAddToHistoryAddToHistory) {
+    // Arrange
+    AlertInfo alert;
+    alert.type = AlertType::SENSOR_FAILURE;
+    alert.status = AlertStatus::ACTIVE;
+    alert.trigger_time = getMockTimestamp();
+    alert.description = "Test alert";
+    
+    // Act
+    alert_manager.addToHistory(alert);
+    
+    // Assert
+    EXPECT_EQ(alert_manager.getAlertHistory(1).size(), 1);
+}
+
+// Test triggerAlert - Trigger New Alert
+TEST_F(AlertManagerTest, testTriggerAlertTriggerNewAlert) {
+    // Arrange
+    uint32_t timestamp = getMockTimestamp();
+    string description = "Test trigger";
+    
+    // Act
+    alert_manager.triggerAlert(AlertType::SENSOR_FAILURE, timestamp, description);
+    
+    // Assert
+    EXPECT_TRUE(alert_manager.hasActiveAlerts());
+    auto active_alerts = alert_manager.getActiveAlerts();
+    EXPECT_EQ(active_alerts.size(), 1);
+    EXPECT_EQ(active_alerts[0].type, AlertType::SENSOR_FAILURE);
+    EXPECT_EQ(active_alerts[0].description, description);
+}
+
+// Test updateAlertStatus - Update to Acknowledged
+TEST_F(AlertManagerTest, testUpdateAlertStatusUpdateToAcknowledged) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    
+    // Act
+    alert_manager.updateAlertStatus(AlertType::SENSOR_FAILURE, AlertStatus::ACKNOWLEDGED, getMockTimestamp());
+    
+    // Assert
+    auto active_alerts = alert_manager.getActiveAlerts();
+    EXPECT_EQ(active_alerts.size(), 1);
+    EXPECT_EQ(active_alerts[0].status, AlertStatus::ACKNOWLEDGED);
+}
+
+// Test updateAlertStatus - Update to Resolved
+TEST_F(AlertManagerTest, testUpdateAlertStatusUpdateToResolved) {
+    // Arrange
+    alert_manager.triggerSensorFailure(getMockTimestamp());
+    
+    // Act
+    alert_manager.updateAlertStatus(AlertType::SENSOR_FAILURE, AlertStatus::RESOLVED, getMockTimestamp());
+    
+    // Assert
+    auto active_alerts = alert_manager.getActiveAlerts();
+    EXPECT_EQ(active_alerts.size(), 1);
+    EXPECT_EQ(active_alerts[0].status, AlertStatus::RESOLVED);
+}
+
+// Test getAlertTypeName - Valid Type
+TEST_F(AlertManagerTest, testGetAlertTypeNameValidType) {
+    // Arrange
+    AlertType type = AlertType::ALTITUDE_UPPER;
+    
+    // Act
+    string result = alert_manager.getAlertTypeName(type);
+    
+    // Assert
+    EXPECT_EQ(result, "高度上限预警");
+}
+
+// Test getAlertTypeName - Unknown Type
+TEST_F(AlertManagerTest, testGetAlertTypeNameUnknownType) {
+    // Arrange
+    AlertType type = static_cast<AlertType>(999);
+    
+    // Act
+    string result = alert_manager.getAlertTypeName(type);
+    
+    // Assert
+    EXPECT_EQ(result, "未知预警");
+}
+
+// Test getAlertStatusName - Valid Status
+TEST_F(AlertManagerTest, testGetAlertStatusNameValidStatus) {
+    // Arrange
+    AlertStatus status = AlertStatus::ACTIVE;
+    
+    // Act
+    string result = alert_manager.getAlertStatusName(status);
+    
+    // Assert
+    EXPECT_EQ(result, "预警中");
+}
+
+// Test getAlertStatusName - Unknown Status
+TEST_F(AlertManagerTest, testGetAlertStatusNameUnknownStatus) {
+    // Arrange
+    AlertStatus status = static_cast<AlertStatus>(999);
+    
+    // Act
+    string result = alert_manager.getAlertStatusName(status);
+    
+    // Assert
+    EXPECT_EQ(result, "未知状态");
 }
\ No newline at end of file