use ruma::{CanonicalJsonObject, CanonicalJsonValue, OwnedEventId, OwnedRoomId};
use serde_json::value::RawValue as RawJsonValue;
use tuwunel_core::{
	Result, err, implement, matrix::event::gen_event_id_canonical_json, result::FlatOk,
};

type Parsed = (OwnedRoomId, OwnedEventId, CanonicalJsonObject);

#[implement(super::Service)]
pub async fn parse_incoming_pdu(&self, pdu: &RawJsonValue) -> Result<Parsed> {
	let value = serde_json::from_str::<CanonicalJsonObject>(pdu.get()).map_err(|e| {
		err!(BadServerResponse(debug_warn!("Error parsing incoming event {e:?}")))
	})?;

	let room_id: OwnedRoomId = value
		.get("room_id")
		.and_then(CanonicalJsonValue::as_str)
		.map(OwnedRoomId::parse)
		.flat_ok_or(err!(Request(InvalidParam("Invalid room_id in pdu"))))?;

	let room_version_id = self
		.services
		.state
		.get_room_version(&room_id)
		.await
		.map_err(|_| err!("Server is not in room {room_id}"))?;

	let (event_id, value) = gen_event_id_canonical_json(pdu, &room_version_id).map_err(|e| {
		err!(Request(InvalidParam("Could not convert event to canonical json: {e}")))
	})?;

	Ok((room_id, event_id, value))
}