//! Key Rotation Module
//!
//! Provides automatic key rotation scheduling and management with
//! configurable policies and comprehensive error handling.

use std::collections::HashMap;

use async_trait::async_trait;
use tokio_cron_scheduler::{Job, JobScheduler};

use crate::kms::error::KmsError;
use crate::kms::traits::KeyRotation;
use crate::kms::types::{HealthStatus, RotationPolicy, RotationState, RotationStatus};

/// Key rotation scheduler and manager
pub struct RotationScheduler {
    scheduler: JobScheduler,
    policy: RotationPolicy,
    /// Status tracking for scheduled key rotations (planned feature)
    #[allow(dead_code)]
    rotation_status: HashMap<String, RotationStatus>,
}

impl RotationScheduler {
    /// Create a new rotation scheduler
    pub async fn new(policy: RotationPolicy) -> Result<Self, KmsError> {
        let scheduler = JobScheduler::new()
            .await
            .map_err(|e| KmsError::rotation("", format!("Failed to create scheduler: {}", e)))?;

        Ok(Self {
            scheduler,
            policy,
            rotation_status: HashMap::new(),
        })
    }

    /// Start the rotation scheduler
    pub async fn start(&mut self) -> Result<(), KmsError> {
        if !self.policy.enabled {
            return Ok(());
        }

        self.scheduler
            .start()
            .await
            .map_err(|e| KmsError::rotation("", format!("Failed to start scheduler: {}", e)))?;

        // Schedule rotation job
        if let Some(schedule) = &self.policy.schedule {
            let job = Job::new_async(schedule, |_uuid, _l| {
                Box::pin(async move {
                    // TODO: Implement rotation logic
                })
            })
            .map_err(|e| KmsError::rotation("", format!("Failed to create rotation job: {}", e)))?;

            self.scheduler.add(job).await.map_err(|e| {
                KmsError::rotation("", format!("Failed to add rotation job: {}", e))
            })?;
        }

        Ok(())
    }

    /// Shutdown the scheduler
    pub async fn shutdown(&mut self) -> Result<(), KmsError> {
        self.scheduler
            .shutdown()
            .await
            .map_err(|e| KmsError::rotation("", format!("Failed to shutdown scheduler: {}", e)))?;
        Ok(())
    }

    /// Health check
    pub async fn health_check(&self) -> Result<HealthStatus, KmsError> {
        Ok(HealthStatus::healthy("Key rotation scheduler operational"))
    }
}

#[async_trait]
impl KeyRotation for RotationScheduler {
    async fn needs_rotation(&self, _key_id: &str) -> Result<bool, KmsError> {
        // TODO: Implement rotation check logic
        Ok(false)
    }

    async fn rotate_key(&self, _key_id: &str) -> Result<String, KmsError> {
        // TODO: Implement key rotation logic
        Err(KmsError::rotation("", "Key rotation not yet implemented"))
    }

    async fn schedule_rotation(&self, _key_id: &str, _schedule: &str) -> Result<(), KmsError> {
        // TODO: Implement rotation scheduling
        Ok(())
    }

    async fn cancel_rotation(&self, _key_id: &str) -> Result<bool, KmsError> {
        // TODO: Implement rotation cancellation
        Ok(false)
    }

    async fn rotation_status(&self, key_id: &str) -> Result<RotationStatus, KmsError> {
        // TODO: Implement status retrieval
        Ok(RotationStatus {
            key_id: key_id.to_string(),
            current_version: 1,
            next_rotation: None,
            last_rotation: None,
            rotation_policy: "default".to_string(),
            status: RotationState::Disabled,
            failure_count: 0,
            last_error: None,
        })
    }

    async fn list_scheduled_rotations(&self) -> Result<Vec<String>, KmsError> {
        // TODO: Implement scheduled rotations list
        Ok(Vec::new())
    }

    async fn health_check(&self) -> Result<HealthStatus, KmsError> {
        self.health_check().await
    }
}
