use anyhow::Result;
use uuid::Uuid;

use crate::models::license::License;

/// License validation and lifecycle management.
///
/// Handles license key validation, activation (binding a key to a server),
/// periodic check-ins from the Rust plugin, and license lookups.
/// All license state is stored in PostgreSQL.
pub struct LicenseService {
    // TODO: Add fields:
    // - db: sqlx::PgPool
}

impl LicenseService {
    /// Validate a license key and return its current status.
    ///
    /// Checks: key exists, not expired, not revoked, modules enabled.
    pub async fn validate_license(&self, _license_key: &str) -> Result<Option<License>> {
        // TODO: Query license by key from DB
        // TODO: Check status is 'active'
        // TODO: Check expires_at is in the future (if set)
        // TODO: Return Some(license) if valid, None if not found
        todo!()
    }

    /// Activate a license key: bind it to a server name and subdomain.
    ///
    /// Called during initial setup when a user first registers.
    pub async fn activate_license(
        &self,
        _license_key: &str,
        _server_name: &str,
        _subdomain: &str,
    ) -> Result<License> {
        // TODO: Validate license key exists and is in 'pending' status
        // TODO: Check subdomain availability
        // TODO: Update license record: status='active', server_name, subdomain
        // TODO: Create default roles for this license
        // TODO: Return updated license
        todo!()
    }

    /// Process a check-in from the Rust server plugin.
    ///
    /// Updates last-seen timestamp and returns current license state
    /// including enabled modules and NATS connection token.
    pub async fn check_in(
        &self,
        _license_key: &str,
        _plugin_version: &str,
    ) -> Result<crate::models::license::LicenseCheckInResponse> {
        // TODO: Validate license
        // TODO: Update plugin_last_seen timestamp on server_connections
        // TODO: Generate or refresh NATS auth token for this license
        // TODO: Return LicenseCheckInResponse with modules and token
        todo!()
    }

    /// Look up a license by its UUID.
    pub async fn get_license_by_key(&self, _license_id: Uuid) -> Result<Option<License>> {
        // TODO: Query license by ID from DB
        // TODO: Return if found
        todo!()
    }
}
