use crate::BucketTransferProtocol;

/// A placeholder implementation of the bucket transfer protocol.
///
/// This struct serves as a temporary or stub implementation of
/// [`BucketTransferProtocol`], intended for use in contexts where
/// actual data transfer is not required (e.g., testing, scaffolding,
/// or as a default before a real implementation is provided).
///
/// Calling any of the transfer methods on this implementation will
/// result in a panic with `unreachable!()`, signaling that the
/// placeholder should be replaced before use.
pub struct NoProtocol;

impl BucketTransferProtocol for NoProtocol {
    type ExtraInfo = ();

    fn upload_to_bucket(
        &self,
        _req: &super::UploadToBucketRequest<Self::ExtraInfo>,
    ) -> Result<(), super::BucketTransferProtocolError> {
        unreachable!()
    }

    fn download_from_bucket(
        &self,
        _req: &super::DownloadFromBucketRequest<Self::ExtraInfo>,
    ) -> Result<(), super::BucketTransferProtocolError> {
        unreachable!()
    }

    fn transfer_to_client(
        &self,
        _req: &super::TransferToClientRequest<Self::ExtraInfo>,
    ) -> Result<(), super::BucketTransferProtocolError> {
        unreachable!()
    }

    fn receive_from_client(
        &self,
        _req: &super::ReceiveFromClientRequest<Self::ExtraInfo>,
    ) -> Result<(), super::BucketTransferProtocolError> {
        unreachable!()
    }
}