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

// Mock time function for deterministic testing
uint32_t mock_timestamp = 1640995200; // 2022-01-01 00:00:00 UTC

// Mock the time function to return a fixed value
uint32_t getMockTimestamp() {
    return mock_timestamp;
}

// Override the triggerAlert and updateAlertStatus methods for testing
void AlertManager::triggerAlert(AlertType type, uint32_t timestamp, const std::string& description) {
    AlertInfo alert;
    alert.type = type;
    alert.status = AlertStatus::ACTIVE;
    alert.trigger_time = timestamp;
    alert.description = description;
    alerts_[type] = alert;
    addToHistory(alert);
}

void AlertManager::updateAlertStatus(AlertType type, AlertStatus new_status, uint32_t timestamp) {
    auto it = alerts_.find(type);
    if (it == alerts_.end()) {
        return;
    }
    AlertInfo& alert = it->second;
    alert.status = new_status;
    switch (new_status) {
        case AlertStatus::ACKNOWLEDGED:
            alert.acknowledge_time = timestamp;
            break;
        case AlertStatus::RESOLVED:
            alert.resolve_time = timestamp;
            break;
        default:
            break;
    }
    // Update history
    for (auto& hist_alert : alert_history_) {
        if (hist_alert.type == type && hist_alert.trigger_time == alert.trigger_time) {
            hist_alert = alert;
            break;
        }
    }
}

// Test fixture for AlertManager
class AlertManagerTest : public ::testing::Test {
protected:
    std::unique_ptr<AlertManager> alert_manager_;

    void SetUp() override {
        alert_manager_ = std::make_unique<AlertManager>();
        mock_timestamp = 1640995200;
    }

    void TearDown() override {
        alert_manager_->clearHistory();
    }
};

// Test checkAltitudeAlert with normal input
TEST_F(AlertManagerTest, testCheckAltitudeAlertNormalInput) {
    // Arrange
    const float altitude = 120.0f;
    const uint32_t timestamp = getMockTimestamp();
    alert_manager_->setAltitudeThresholds(100.0f, -50.0f);

    // Act
    alert_manager_->checkAltitudeAlert(altitude, 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::ALTITUDE_UPPER);
    EXPECT_EQ(active_alerts[0].status, AlertStatus::ACTIVE);
    EXPECT_EQ(active_alerts[0].trigger_time, timestamp);
    EXPECT_EQ(active_alerts[0].description, "高度超过上限阈值：当前120米 > 阈值100米");
}

// Test checkAltitudeAlert when altitude is within bounds
TEST_F(AlertManagerTest, testCheckAltitudeAlertWithinBounds) {
    // Arrange
    const float altitude = 80.0f;
    const uint32_t timestamp = getMockTimestamp();
    alert_manager_->setAltitudeThresholds(100.0f, -50.0f);

    // Act
    alert_manager_->checkAltitudeAlert(altitude, timestamp);

    // Assert
    EXPECT_FALSE(alert_manager_->hasActiveAlerts());
    EXPECT_EQ(alert_manager_->getActiveAlerts().size(), 0);
}

// Test checkAltitudeAlert when altitude crosses lower threshold
TEST_F(AlertManagerTest, testCheckAltitudeAlertLowerThresholdCrossed) {
    // Arrange
    const float altitude = -60.0f;
    const uint32_t timestamp = getMockTimestamp();
    alert_manager_->setAltitudeThresholds(100.0f, -50.0f);

    // Act
    alert_manager_->checkAltitudeAlert(altitude, 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::ALTITUDE_LOWER);
    EXPECT_EQ(active_alerts[0].status, AlertStatus::ACTIVE);
    EXPECT_EQ(active_alerts[0].trigger_time, timestamp);
    EXPECT_EQ(active_alerts[0].description, "高度低于下限阈值：当前-60米 < 阈值-50米");
}

// Test setAltitudeThresholds with valid inputs
TEST_F(AlertManagerTest, testSetAltitudeThresholdsValidInputs) {
    // Arrange
    const float upper = 150.0f;
    const float lower = -70.0f;

    // Act
    alert_manager_->setAltitudeThresholds(upper, lower);

    // Assert
    EXPECT_FLOAT_EQ(alert_manager_->getUpperThreshold(), upper);
    EXPECT_FLOAT_EQ(alert_manager_->getLowerThreshold(), lower);
    EXPECT_FALSE(alert_manager_->hasActiveAlerts());
}

// Test setAltitudeThresholds with invalid inputs (upper <= lower)
TEST_F(AlertManagerTest, testSetAltitudeThresholdsInvalidInputs) {
    // Arrange
    const float upper = 50.0f;
    const float lower = 100.0f;

    // Act & Assert
    EXPECT_NO_THROW(alert_manager_->setAltitudeThresholds(upper, lower));
    EXPECT_TRUE(alert_manager_->hasActiveAlerts());
    EXPECT_EQ(alert_manager_->getActiveAlerts().size(), 0);
}

// Test checkAltitudeAlert after threshold change
TEST_F(AlertManagerTest, testCheckAltitudeAlertAfterThresholdChange) {
    // Arrange
    const float altitude = 120.0f;
    const uint32_t timestamp = getMockTimestamp();
    alert_manager_->setAltitudeThresholds(100.0f, -50.0f);

    // Act
    alert_manager_->checkAltitudeAlert(altitude, 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::ALTITUDE_UPPER);

    // Change threshold to allow altitude to be valid
    alert_manager_->setAltitudeThresholds(130.0f, -50.0f);

    // Re-check
    alert_manager_->checkAltitudeAlert(altitude, timestamp + 1);

    // Assert that alert is resolved
    EXPECT_FALSE(alert_manager_->hasActiveAlerts());
}

// Test checkAltitudeAlert with zero altitude
TEST_F(AlertManagerTest, testCheckAltitudeAlertZeroAltitude) {
    // Arrange
    const float altitude = 0.0f;
    const uint32_t timestamp = getMockTimestamp();
    alert_manager_->setAltitudeThresholds(100.0f, -50.0f);

    // Act
    alert_manager_->checkAltitudeAlert(altitude, timestamp);

    // Assert
    EXPECT_FALSE(alert_manager_->hasActiveAlerts());
    EXPECT_EQ(alert_manager_->getActiveAlerts().size(), 0);
}

// Test checkAltitudeAlert with extreme values
TEST_F(AlertManagerTest, testCheckAltitudeAlertExtremeValues) {
    // Arrange
    const float altitude = 1e6f; // Very high
    const uint32_t timestamp = getMockTimestamp();
    alert_manager_->setAltitudeThresholds(100.0f, -50.0f);

    // Act
    alert_manager_->checkAltitudeAlert(altitude, 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::ALTITUDE_UPPER);
    EXPECT_EQ(active_alerts[0].status, AlertStatus::ACTIVE);
    EXPECT_EQ(active_alerts[0].trigger_time, timestamp);
    EXPECT_NE(active_alerts[0].description.find("1e+06"), std::string::npos);
}

// Test setAltitudeThresholds with equal values
TEST_F(AlertManagerTest, testSetAltitudeThresholdsEqualValues) {
    // Arrange
    const float upper = 100.0f;
    const float lower = 100.0f;

    // Act & Assert
    EXPECT_NO_THROW(alert_manager_->setAltitudeThresholds(upper, lower));
    EXPECT_TRUE(alert_manager_->hasActiveAlerts());
    EXPECT_EQ(alert_manager_->getActiveAlerts().size(), 0);
}

// Test checkAltitudeAlert with negative altitude below lower threshold
TEST_F(AlertManagerTest, testCheckAltitudeAlertNegativeBelowLower) {
    // Arrange
    const float altitude = -100.0f;
    const uint32_t timestamp = getMockTimestamp();
    alert_manager_->setAltitudeThresholds(100.0f, -50.0f);

    // Act
    alert_manager_->checkAltitudeAlert(altitude, 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::ALTITUDE_LOWER);
    EXPECT_EQ(active_alerts[0].status, AlertStatus::ACTIVE);
    EXPECT_EQ(active_alerts[0].trigger_time, timestamp);
    EXPECT_EQ(active_alerts[0].description, "高度低于下限阈值：当前-100米 < 阈值-50米");
}

// Test checkAltitudeAlert with altitude exactly at upper threshold
TEST_F(AlertManagerTest, testCheckAltitudeAlertAtUpperThreshold) {
    // Arrange
    const float altitude = 100.0f;
    const uint32_t timestamp = getMockTimestamp();
    alert_manager_->setAltitudeThresholds(100.0f, -50.0f);

    // Act
    alert_manager_->checkAltitudeAlert(altitude, timestamp);

    // Assert
    EXPECT_FALSE(alert_manager_->hasActiveAlerts());
    EXPECT_EQ(alert_manager_->getActiveAlerts().size(), 0);
}

// Test checkAltitudeAlert with altitude exactly at lower threshold
TEST_F(AlertManagerTest, testCheckAltitudeAlertAtLowerThreshold) {
    // Arrange
    const float altitude = -50.0f;
    const uint32_t timestamp = getMockTimestamp();
    alert_manager_->setAltitudeThresholds(100.0f, -50.0f);

    // Act
    alert_manager_->checkAltitudeAlert(altitude, timestamp);

    // Assert
    EXPECT_FALSE(alert_manager_->hasActiveAlerts());
    EXPECT_EQ(alert_manager_->getActiveAlerts().size(), 0);
}