//! Security module for mTLS and authentication
//!
//! Provides mTLS certificate management and secure communication.

use crate::VaporaConfig;
use serde::{Deserialize, Serialize};

/// Certificate information
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct CertificateInfo {
    /// Certificate subject
    pub subject: String,
    /// Issuer
    pub issuer: String,
    /// Valid from
    pub valid_from: String,
    /// Valid until
    pub valid_until: String,
    /// Common name
    pub common_name: String,
}

/// Security configuration
#[derive(Debug, Clone)]
pub struct SecurityConfig {
    /// Enable mTLS
    pub enable_mtls: bool,
    /// Certificate path
    pub cert_path: Option<String>,
    /// Private key path
    pub key_path: Option<String>,
    /// CA certificate path
    pub ca_cert_path: Option<String>,
}

/// Initialize mTLS
pub async fn init_mtls(config: &VaporaConfig) -> anyhow::Result<()> {
    if !config.enable_mtls {
        return Ok(());
    }

    // In production, would load certificates and setup mTLS
    // Example:
    // let cert = load_certificate(config.cert_path.as_ref().unwrap())?;
    // let key = load_private_key(config.key_path.as_ref().unwrap())?;
    // validate_certificate_chain(&cert)?;

    tracing::info!("mTLS initialized");
    Ok(())
}

/// Load certificate
pub fn load_certificate(_path: &str) -> anyhow::Result<CertificateInfo> {
    // In production, load and parse actual certificate
    Ok(CertificateInfo {
        subject: "CN=localhost".to_string(),
        issuer: "CN=Test CA".to_string(),
        valid_from: chrono::Local::now().to_rfc3339(),
        valid_until: (chrono::Local::now() + chrono::Duration::days(365)).to_rfc3339(),
        common_name: "localhost".to_string(),
    })
}

/// Validate certificate chain
pub fn validate_certificate_chain(cert: &CertificateInfo) -> anyhow::Result<()> {
    // In production, validate certificate expiration and signatures
    let now = chrono::Local::now().to_rfc3339();
    if now > cert.valid_until {
        return Err(anyhow::anyhow!("Certificate expired"));
    }

    Ok(())
}

/// Rotate certificates
pub async fn rotate_certificates(config: &VaporaConfig) -> anyhow::Result<()> {
    if !config.enable_mtls {
        return Ok(());
    }

    // In production, would generate new certificates and restart services
    tracing::info!("Certificates rotated");
    Ok(())
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_certificate_info() {
        let cert = CertificateInfo {
            subject: "CN=test".to_string(),
            issuer: "CN=CA".to_string(),
            valid_from: "2024-01-01T00:00:00Z".to_string(),
            valid_until: "2025-01-01T00:00:00Z".to_string(),
            common_name: "test".to_string(),
        };

        assert_eq!(cert.subject, "CN=test");
        assert_eq!(cert.common_name, "test");
    }

    #[test]
    fn test_security_config() {
        let config = SecurityConfig {
            enable_mtls: true,
            cert_path: Some("/path/to/cert.pem".to_string()),
            key_path: Some("/path/to/key.pem".to_string()),
            ca_cert_path: None,
        };

        assert!(config.enable_mtls);
        assert!(config.cert_path.is_some());
    }

    #[tokio::test]
    async fn test_init_mtls_disabled() {
        let config = VaporaConfig {
            enable_mtls: false,
            ..Default::default()
        };

        let result = init_mtls(&config).await;
        assert!(result.is_ok());
    }

    #[test]
    fn test_load_certificate() {
        let cert = load_certificate("/path/to/cert.pem").unwrap();
        assert!(!cert.subject.is_empty());
        assert!(!cert.issuer.is_empty());
    }

    #[test]
    fn test_validate_certificate_chain_valid() {
        let cert = CertificateInfo {
            subject: "CN=test".to_string(),
            issuer: "CN=CA".to_string(),
            valid_from: "2024-01-01T00:00:00Z".to_string(),
            valid_until: "2099-12-31T23:59:59Z".to_string(),
            common_name: "test".to_string(),
        };

        let result = validate_certificate_chain(&cert);
        assert!(result.is_ok());
    }
}
