use crate::app::ports::driven::{
    ForFormattingMessage, ForMonitoringSystem, ForSendingNotification,
};

pub struct AlertService {
    notifier: Box<dyn ForSendingNotification>,
    monitor: Box<dyn ForMonitoringSystem>,
    formatter: Box<dyn ForFormattingMessage>,
}

pub fn new(
    notifier: Box<dyn ForSendingNotification>,
    monitor: Box<dyn ForMonitoringSystem>,
    formatter: Box<dyn ForFormattingMessage>,
) -> AlertService {
    AlertService {
        notifier,
        monitor,
        formatter,
    }
}

impl AlertService {
    /// Check for threshold violations and send alerts
    pub fn alert_on_threshold_violation(&self) -> Result<(), Box<dyn std::error::Error>> {
        let violations = self.monitor.check_thresholds();
        for violation in violations {
            let message = self.formatter.format_violation(violation);
            self.notifier.send_notification(&message)?;
        }
        
        Ok(())
    }
}


#[cfg(test)]
mod tests {
    use std::collections::HashMap;

    use crate::app::ports::driven::{MockForFormattingMessage, MockForMonitoringSystem, MockForSendingNotification};

    use super::*;

    #[test]
    fn test_alert_on_threshold_violation() {
        let mut notifier = MockForSendingNotification::new();
        let mut monitor = MockForMonitoringSystem::new();
        let mut formatter = MockForFormattingMessage::new();

        notifier.expect_send_notification().returning(|_| Ok(()));
        monitor.expect_check_thresholds().returning(|| vec![]);
        monitor.expect_get_metrics().returning(|| HashMap::new());
        formatter.expect_format_violation().returning(|_| "".to_string());
        formatter.expect_format_summary().returning(|_| "".to_string());

        let service = new(
            Box::new(notifier),
            Box::new(monitor),
            Box::new(formatter),
        );

        assert!(service.alert_on_threshold_violation().is_ok());
    }

    #[test]
    fn test_alert_on_threshold_violation_handles_send_error() {
        let mut notifier = MockForSendingNotification::new();
        let mut monitor = MockForMonitoringSystem::new();
        let mut formatter = MockForFormattingMessage::new();

        monitor.expect_check_thresholds().returning(|| {
            vec![Box::new(crate::app::ports::driven::MockForGettingViolationData::new())]
        });
        formatter.expect_format_violation().returning(|_| "Test violation".to_string());
        
        notifier.expect_send_notification()
            .returning(|_| Err("Network error".into()));

        let service = new(
            Box::new(notifier),
            Box::new(monitor),
            Box::new(formatter),
        );

        assert!(service.alert_on_threshold_violation().is_err());
    }
}