use crate::remote::connection::HandshakeWithRefs;
use crate::remote::{Connection, Direction};
use git_features::progress::Progress;
use git_protocol::transport::client::Transport;

mod error {
    #[derive(Debug, thiserror::Error)]
    pub enum Error {
        #[error(transparent)]
        Handshake(#[from] git_protocol::fetch::handshake::Error),
        #[error(transparent)]
        ListRefs(#[from] git_protocol::fetch::refs::Error),
        #[error(transparent)]
        Transport(#[from] git_protocol::transport::client::Error),
    }
}
pub use error::Error;

impl<'a, 'repo, T, P> Connection<'a, 'repo, T, P>
where
    T: Transport,
    P: Progress,
{
    /// List all references on the remote.
    ///
    /// Note that this doesn't fetch the objects mentioned in the tips nor does it make any change to underlying repository.
    #[git_protocol::maybe_async::maybe_async]
    pub async fn list_refs(mut self) -> Result<Vec<git_protocol::fetch::Ref>, Error> {
        let res = self.fetch_refs().await?;
        git_protocol::fetch::indicate_end_of_interaction(&mut self.transport).await?;
        Ok(res.refs)
    }

    #[git_protocol::maybe_async::maybe_async]
    async fn fetch_refs(&mut self) -> Result<HandshakeWithRefs, Error> {
        let mut outcome = git_protocol::fetch::handshake(
            &mut self.transport,
            git_protocol::credentials::helper,
            Vec::new(),
            &mut self.progress,
        )
        .await?;
        let refs = match outcome.refs.take() {
            Some(refs) => refs,
            None => {
                git_protocol::fetch::refs(
                    &mut self.transport,
                    outcome.server_protocol_version,
                    &outcome.capabilities,
                    |_a, _b, _c| Ok(git_protocol::fetch::delegate::LsRefsAction::Continue),
                    &mut self.progress,
                )
                .await?
            }
        };
        Ok(HandshakeWithRefs { outcome, refs })
    }

    /// List all references on the remote that have been filtered through our remote's [`refspecs`][crate::Remote::refspecs()]
    /// for _fetching_ or _pushing_ depending on `direction`.
    ///
    /// This comes in the form of information of all matching tips on the remote and the object they point to, along with
    /// with the local tracking branch of these tips (if available).
    ///
    /// Note that this doesn't fetch the objects mentioned in the tips nor does it make any change to underlying repository.
    pub fn list_refs_by_refspec(&mut self, _direction: Direction) -> ! {
        todo!()
    }
}