#include "gtest/gtest.h"
#include "alert_manager.hpp"
#include <vector>
#include <string>

using namespace std;

// Mock time for consistent test results
uint32_t mock_time = 1640995200; // 2022-01-01 00:00:00 UTC

// Mock function to replace std::time
extern "C" uint32_t time(time_t* t) {
    if (t) *t = mock_time;
    return mock_time;
}

// Test fixture for AlertManager
class AlertManagerTest : public ::testing::Test {
protected:
    AlertManager alert_manager;

    void SetUp() override {
        mock_time = 1640995200;
        alert_manager.initialize();
    }

    void TearDown() override {
        alert_manager.resetAllAlerts();
    }
};

// Test case: AlertManager 构造函数初始化默认阈值
TEST_F(AlertManagerTest, testAlertManagerConstructor) {
    EXPECT_FLOAT_EQ(alert_manager.getAltitudeThresholds().first, 100.0f);
    EXPECT_FLOAT_EQ(alert_manager.getAltitudeThresholds().second, -50.0f);
    EXPECT_TRUE(alert_manager.alerts_.empty());
    EXPECT_TRUE(alert_manager.alert_history_.empty());
}

// Test case: AlertManager 析构函数无副作用
TEST_F(AlertManagerTest, testAlertManagerDestructor) {
    // No specific assertion needed as destructor has no logic
    // Just ensure it compiles and runs without crash
    EXPECT_NO_FATAL_FAILURE({});
}

// Test case: initialize 输出初始化信息
TEST_F(AlertManagerTest, testInitializeOutput) {
    testing::internal::CaptureStdout();
    alert_manager.initialize();
    string output = testing::internal::GetCapturedStdout();
    EXPECT_NE(output.find("预警管理器初始化完成。"), string::npos);
    EXPECT_NE(output.find("默认预警阈值：上限=100米，下限=-50米"), string::npos);
}

// Test case: checkAltitudeAlert 正常高度不触发预警
TEST_F(AlertManagerTest, testCheckAltitudeAlertNormalHeight) {
    alert_manager.checkAltitudeAlert(50.0f, mock_time);
    EXPECT_FALSE(alert_manager.hasActiveAlerts());
}

// Test case: checkAltitudeAlert 超过上限触发预警
TEST_F(AlertManagerTest, testCheckAltitudeAlertUpperThreshold) {
    alert_manager.checkAltitudeAlert(101.0f, mock_time);
    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 case: checkAltitudeAlert 低于下限触发预警
TEST_F(AlertManagerTest, testCheckAltitudeAlertLowerThreshold) {
    alert_manager.checkAltitudeAlert(-51.0f, mock_time);
    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 case: checkAltitudeAlert 高度恢复后解除预警
TEST_F(AlertManagerTest, testCheckAltitudeAlertResolution) {
    alert_manager.checkAltitudeAlert(101.0f, mock_time);
    alert_manager.checkAltitudeAlert(99.0f, mock_time + 1);
    EXPECT_FALSE(alert_manager.hasActiveAlerts());
}

// Test case: setAltitudeThresholds 设置合法阈值
TEST_F(AlertManagerTest, testSetAltitudeThresholdsValid) {
    alert_manager.setAltitudeThresholds(200.0f, -100.0f);
    EXPECT_FLOAT_EQ(alert_manager.getAltitudeThresholds().first, 200.0f);
    EXPECT_FLOAT_EQ(alert_manager.getAltitudeThresholds().second, -100.0f);
}

// Test case: setAltitudeThresholds 设置非法阈值（上界 <= 下界）
TEST_F(AlertManagerTest, testSetAltitudeThresholdsInvalid) {
    testing::internal::CaptureStderr();
    alert_manager.setAltitudeThresholds(50.0f, 100.0f);
    string error_output = testing::internal::GetCapturedStderr();
    EXPECT_NE(error_output.find("错误：上限阈值必须大于下限阈值。"), string::npos);
    EXPECT_FLOAT_EQ(alert_manager.getAltitudeThresholds().first, 100.0f);
    EXPECT_FLOAT_EQ(alert_manager.getAltitudeThresholds().second, -50.0f);
}

// Test case: triggerSensorFailure 触发传感器故障预警
TEST_F(AlertManagerTest, testTriggerSensorFailure) {
    alert_manager.triggerSensorFailure(mock_time);
    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, "传感器故障");
}

// Test case: triggerLowBattery 触发低电量预警
TEST_F(AlertManagerTest, testTriggerLowBattery) {
    alert_manager.triggerLowBattery(mock_time, 15.5f);
    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].description, "低电量警告：当前电量15.5%");
}

// Test case: triggerCommunicationError 触发通信错误预警
TEST_F(AlertManagerTest, testTriggerCommunicationError) {
    alert_manager.triggerCommunicationError(mock_time);
    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].description, "通信错误");
}

// Test case: acknowledgeAllAlerts 确认所有活动预警
TEST_F(AlertManagerTest, testAcknowledgeAllAlerts) {
    alert_manager.triggerSensorFailure(mock_time);
    alert_manager.triggerLowBattery(mock_time + 1, 10.0f);
    alert_manager.acknowledgeAllAlerts(mock_time + 2);
    EXPECT_FALSE(alert_manager.hasUnacknowledgedAlerts());
}

// Test case: acknowledgeAlert 确认指定类型预警
TEST_F(AlertManagerTest, testAcknowledgeAlert) {
    alert_manager.triggerSensorFailure(mock_time);
    alert_manager.acknowledgeAlert(AlertType::SENSOR_FAILURE, mock_time + 1);
    auto active_alerts = alert_manager.getActiveAlerts();
    EXPECT_EQ(active_alerts.size(), 0);
    EXPECT_TRUE(alert_manager.hasUnacknowledgedAlerts());
}

// Test case: resetAlert 重置指定类型预警
TEST_F(AlertManagerTest, testResetAlert) {
    alert_manager.triggerSensorFailure(mock_time);
    alert_manager.resetAlert(AlertType::SENSOR_FAILURE);
    EXPECT_FALSE(alert_manager.hasActiveAlerts());
}

// Test case: resetAllAlerts 重置所有预警
TEST_F(AlertManagerTest, testResetAllAlerts) {
    alert_manager.triggerSensorFailure(mock_time);
    alert_manager.triggerLowBattery(mock_time + 1, 10.0f);
    alert_manager.resetAllAlerts();
    EXPECT_FALSE(alert_manager.hasActiveAlerts());
    EXPECT_TRUE(alert_manager.alerts_.empty());
}

// Test case: hasActiveAlerts 检查是否存在活动预警
TEST_F(AlertManagerTest, testHasActiveAlerts) {
    EXPECT_FALSE(alert_manager.hasActiveAlerts());
    alert_manager.triggerSensorFailure(mock_time);
    EXPECT_TRUE(alert_manager.hasActiveAlerts());
}

// Test case: hasUnacknowledgedAlerts 检查是否存在未确认预警
TEST_F(AlertManagerTest, testHasUnacknowledgedAlerts) {
    EXPECT_FALSE(alert_manager.hasUnacknowledgedAlerts());
    alert_manager.triggerSensorFailure(mock_time);
    EXPECT_TRUE(alert_manager.hasUnacknowledgedAlerts());
}

// Test case: getActiveAlerts 获取活动预警列表
TEST_F(AlertManagerTest, testGetActiveAlerts) {
    alert_manager.triggerSensorFailure(mock_time);
    auto alerts = alert_manager.getActiveAlerts();
    EXPECT_EQ(alerts.size(), 1);
    EXPECT_EQ(alerts[0].type, AlertType::SENSOR_FAILURE);
}

// Test case: getAlertHistory 获取历史记录（最大数量限制）
TEST_F(AlertManagerTest, testGetAlertHistoryMaxCount) {
    for (int i = 0; i < 10; ++i) {
        alert_manager.triggerSensorFailure(mock_time + i);
    }
    auto history = alert_manager.getAlertHistory(5);
    EXPECT_EQ(history.size(), 5);
}

// Test case: getStatusDescription 生成系统状态描述
TEST_F(AlertManagerTest, testGetStatusDescription) {
    alert_manager.triggerSensorFailure(mock_time);
    string status_desc = alert_manager.getStatusDescription();
    EXPECT_NE(status_desc.find("有1个活动预警"), string::npos);
    EXPECT_NE(status_desc.find("传感器故障"), string::npos);
}

// Test case: clearHistory 清空历史记录
TEST_F(AlertManagerTest, testClearHistory) {
    alert_manager.triggerSensorFailure(mock_time);
    alert_manager.clearHistory();
    EXPECT_TRUE(alert_manager.alert_history_.empty());
}

// Test case: addToHistory 添加历史记录并保持数量限制
TEST_F(AlertManagerTest, testAddToHistoryLimit) {
    const size_t max_count = 5;
    for (int i = 0; i < max_count + 1; ++i) {
        AlertInfo alert;
        alert.type = AlertType::SENSOR_FAILURE;
        alert.status = AlertStatus::ACTIVE;
        alert.trigger_time = mock_time + i;
        alert.description = "Test alert";
        alert_manager.addToHistory(alert);
    }
    EXPECT_EQ(alert_manager.alert_history_.size(), max_count);
}

// Test case: triggerAlert 触发新预警
TEST_F(AlertManagerTest, testTriggerAlert) {
    alert_manager.triggerAlert(AlertType::ALTITUDE_UPPER, mock_time, "Test description");
    EXPECT_TRUE(alert_manager.hasActiveAlerts());
    auto alerts = alert_manager.getActiveAlerts();
    EXPECT_EQ(alerts[0].description, "Test description");
}

// Test case: updateAlertStatus 更新预警状态为已确认
TEST_F(AlertManagerTest, testUpdateAlertStatusAcknowledged) {
    alert_manager.triggerSensorFailure(mock_time);
    alert_manager.updateAlertStatus(AlertType::SENSOR_FAILURE, AlertStatus::ACKNOWLEDGED, mock_time + 1);
    auto alerts = alert_manager.getActiveAlerts();
    EXPECT_EQ(alerts.size(), 0);
    EXPECT_EQ(alerts.size(), 0);
}

// Test case: updateAlertStatus 更新预警状态为已解决
TEST_F(AlertManagerTest, testUpdateAlertStatusResolved) {
    alert_manager.triggerSensorFailure(mock_time);
    alert_manager.updateAlertStatus(AlertType::SENSOR_FAILURE, AlertStatus::RESOLVED, mock_time + 1);
    auto alerts = alert_manager.getActiveAlerts();
    EXPECT_EQ(alerts.size(), 0);
}

// Test case: getAlertTypeName 返回正确名称
TEST_F(AlertManagerTest, testGetAlertTypeName) {
    EXPECT_EQ(alert_manager.getAlertTypeName(AlertType::ALTITUDE_UPPER), "高度上限预警");
    EXPECT_EQ(alert_manager.getAlertTypeName(AlertType::NONE), "无");
}

// Test case: getAlertStatusName 返回正确状态名
TEST_F(AlertManagerTest, testGetAlertStatusName) {
    EXPECT_EQ(alert_manager.getAlertStatusName(AlertStatus::ACTIVE), "预警中");
    EXPECT_EQ(alert_manager.getAlertStatusName(AlertStatus::INACTIVE), "未激活");
}