use chrono::{DateTime, Utc};
use serde::{Deserialize, Serialize};
use uuid::Uuid;

/// Opaque reference to a pre-mutation snapshot owned by the workspace
/// executor.  Reef stores this reference as workflow metadata; it must never
/// contain a host path or the snapshot bytes.
#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
pub struct RollbackReference {
    pub reference_id: Uuid,
    pub execution_id: Uuid,
    pub workspace_lease_id: Uuid,
    pub workspace_id: Uuid,
    pub project_id: Uuid,
    pub expires_at: DateTime<Utc>,
}

impl RollbackReference {
    pub fn is_expired(&self, now: DateTime<Utc>) -> bool {
        self.expires_at <= now
    }

    pub fn validates_execution(&self, execution_id: Uuid) -> bool {
        self.execution_id == execution_id && self.reference_id != Uuid::nil()
    }
}

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

    fn reference() -> RollbackReference {
        RollbackReference {
            reference_id: Uuid::new_v4(),
            execution_id: Uuid::new_v4(),
            workspace_lease_id: Uuid::new_v4(),
            workspace_id: Uuid::new_v4(),
            project_id: Uuid::new_v4(),
            expires_at: Utc::now() + chrono::Duration::minutes(1),
        }
    }

    #[test]
    fn reference_is_opaque_and_execution_bound() {
        let reference = reference();
        assert!(reference.validates_execution(reference.execution_id));
        assert!(!reference.validates_execution(Uuid::new_v4()));
        assert!(!reference.is_expired(Utc::now()));
    }
}