use futures::future::OptionFuture;
use ruma::{CanonicalJsonObject, CanonicalJsonValue, RoomId, RoomVersionId};
use serde_json::value::{RawValue as RawJsonValue, to_raw_value};
use tuwunel_core::{
	implement,
	matrix::pdu,
	utils::{future::TryExtExt, result::FlatOk},
};

/// This does not return a full `Pdu` it is only to satisfy ruma's types.
#[implement(super::Service)]
pub async fn format_pdu_into(
	&self,
	mut pdu_json: CanonicalJsonObject,
	room_version: Option<&RoomVersionId>,
) -> Box<RawJsonValue> {
	let room_id = pdu_json
		.get("room_id")
		.and_then(CanonicalJsonValue::as_str)
		.map(RoomId::parse)
		.flat_ok();

	let query_room_version: OptionFuture<_> = room_id
		.and_then(|room_id| {
			room_version
				.is_none()
				.then(|| self.services.state.get_room_version(room_id))
				.map(TryExtExt::ok)
		})
		.into();

	if let Some(room_version) = query_room_version
		.await
		.flatten()
		.as_ref()
		.or(room_version)
	{
		pdu_json = pdu::format::into_outgoing_federation(pdu_json, room_version);
	} else {
		pdu_json.remove("event_id");
	}

	to_raw_value(&pdu_json).expect("CanonicalJson is valid serde_json::Value")
}