use crate::{
    entities::doc::{RevId, Revision, RevisionRange},
    errors::{internal_error, DocError},
    services::{doc::revision::store_actor::RevisionCmd, util::RevIdCounter, ws::DocumentWebSocket},
};
use flowy_infra::future::ResultFuture;
use flowy_ot::core::Delta;

use tokio::sync::{mpsc, oneshot};

pub struct DocRevision {
    pub rev_id: RevId,
    pub delta: Delta,
}

pub trait RevisionServer: Send + Sync {
    fn fetch_document_from_remote(&self, doc_id: &str) -> ResultFuture<DocRevision, DocError>;
}

pub struct RevisionManager {
    doc_id: String,
    rev_id_counter: RevIdCounter,
    rev_store: mpsc::Sender<RevisionCmd>,
}

impl RevisionManager {
    pub fn new(doc_id: &str, rev_id: RevId, rev_store: mpsc::Sender<RevisionCmd>) -> Self {
        let rev_id_counter = RevIdCounter::new(rev_id.into());
        Self {
            doc_id: doc_id.to_string(),
            rev_id_counter,
            rev_store,
        }
    }

    #[tracing::instrument(level = "debug", skip(self))]
    pub async fn add_revision(&self, revision: &Revision) -> Result<(), DocError> {
        let (ret, rx) = oneshot::channel();
        let cmd = RevisionCmd::Revision {
            revision: revision.clone(),
            ret,
        };
        let _ = self.rev_store.send(cmd).await;
        let result = rx.await.map_err(internal_error)?;
        result
    }

    pub fn ack_rev(&self, rev_id: RevId) -> Result<(), DocError> {
        let sender = self.rev_store.clone();
        tokio::spawn(async move {
            let _ = sender.send(RevisionCmd::AckRevision { rev_id }).await;
        });
        Ok(())
    }

    pub fn rev_id(&self) -> i64 { self.rev_id_counter.value() }

    pub fn next_rev_id(&self) -> (i64, i64) {
        let cur = self.rev_id_counter.value();
        let next = self.rev_id_counter.next();
        (cur, next)
    }

    pub fn update_rev_id(&self, rev_id: i64) { self.rev_id_counter.set(rev_id); }

    pub async fn send_revisions(&self, range: RevisionRange) -> Result<(), DocError> {
        debug_assert!(&range.doc_id == &self.doc_id);
        let (ret, rx) = oneshot::channel();
        let sender = self.rev_store.clone();
        let _ = sender.send(RevisionCmd::SendRevisions { range, ret }).await;
        let _revisions = rx.await.map_err(internal_error)??;

        unimplemented!()
        // Ok(())
    }
}