veilid-core 0.5.3

use super::*;
use crate::storage_manager::{SignedValueData, SignedValueDescriptor};

impl_veilid_log_facility!("rpc");

#[derive(Clone, Debug)]
pub struct GetValueAnswer {
    pub accepted: bool,
    pub value: Option<SignedValueData>,
    pub peers: Vec<Arc<PeerInfo>>,
    pub descriptor: Option<SignedValueDescriptor>,
}

impl RPCProcessor {
    /// Sends a get value request and wait for response
    /// Can be sent via all methods including relays
    /// Safety routes may be used, but never private routes.
    /// Because this leaks information about the identity of the node itself,
    /// replying to this request received over a private route will leak
    /// the identity of the node and defeat the private route.
    #[cfg_attr(feature = "instrument", instrument(level = "trace", target = "rpc", skip(self),
            fields(%descriptor_mode,
                ret.value.data.len,
                ret.value.data.seq,
                ret.value.data.writer,
                ret.peers.len,
                ret.latency,
                ret.accepted
            ),err(level=Level::DEBUG)))]
    pub async fn rpc_call_get_value(
        &self,
        dest: Destination,
        opaque_record_key: OpaqueRecordKey,
        subkey: ValueSubkey,
        descriptor_mode: GetDescriptorMode,
    ) -> RPCNetworkResult<Answer<GetValueAnswer>> {
        let _guard = self
            .startup_context
            .startup_lock
            .enter()
            .map_err(RPCError::map_try_again("not started up"))?;

        // Ensure destination never has a private route
        // and get the target noderef so we can validate the response
        let Some(target_node_ids) = dest.get_target_node_ids() else {
            return Err(RPCError::internal(
                "Never send get value requests over private routes",
            ));
        };

        // Get the target node id
        Crypto::validate_crypto_kind(opaque_record_key.kind()).map_err(RPCError::internal)?;
        let Some(target_node_id) = target_node_ids.get(opaque_record_key.kind()) else {
            return Err(RPCError::internal("No node id for crypto kind"));
        };

        let debug_string = format!(
            "OUT ==> GetValueQ({} #{}{}) => {}",
            opaque_record_key, subkey, descriptor_mode, dest
        );

        // Send the getvalue question
        let get_value_q = RPCOperationGetValueQ::new(
            opaque_record_key.clone(),
            subkey,
            matches!(descriptor_mode, GetDescriptorMode::WantDescriptor),
        )?;
        let question = RPCQuestion::new(
            network_result_try!(self.get_destination_respond_to(&dest).await?),
            RPCQuestionDetail::GetValueQ(Box::new(get_value_q)),
        );

        let question_context = QuestionContext::GetValue(ValidateGetValueContext {
            opaque_record_key: opaque_record_key.clone(),
            descriptor_mode,
            subkey,
        });

        veilid_log!(self debug target: "dht", "{}", debug_string);

        let waitable_reply = network_result_try!(
            self.question(dest.clone(), question, None, Some(question_context))
                .await?
        );

        // Wait for reply
        let (msg, answer_context) = match self.wait_for_reply(waitable_reply, debug_string).await? {
            TimeoutOr::Timeout => return Ok(NetworkResult::Timeout),
            TimeoutOr::Value(v) => v,
        };

        // Get the right answer type
        let (_, _, kind) = msg.operation.destructure();
        let get_value_a = match kind {
            RPCOperationKind::Answer(a) => match a.destructure() {
                RPCAnswerDetail::GetValueA(a) => a,
                _ => return Ok(NetworkResult::invalid_message("not a getvalue answer")),
            },
            _ => return Ok(NetworkResult::invalid_message("not an answer")),
        };

        let (accepted, value, peers, descriptor) = get_value_a.destructure();
        if debug_target_enabled!("dht") {
            let debug_string_value = value.as_ref().map(|v| v.to_string()).unwrap_or_default();

            let debug_string_answer = format!(
                "OUT <== GetValueA({} #{}{}{}{} peers={}) <= {}",
                opaque_record_key,
                subkey,
                debug_string_value,
                if accepted { " +accept" } else { "" },
                if descriptor.is_some() { " +desc" } else { "" },
                peers.len(),
                dest
            );

            veilid_log!(self debug target: "dht", "{}", debug_string_answer);

            let peer_ids: Vec<String> = peers
                .iter()
                .filter_map(|p| {
                    p.node_ids()
                        .get(opaque_record_key.kind())
                        .map(|k| k.to_string())
                })
                .collect();
            veilid_log!(self debug target: "dht", "Peers: {:#?}", peer_ids);
        }

        // Validate peers returned are, in fact, closer to the key than the node we sent this to
        let valid = match self.routing_table().verify_peer_infos_closer(
            target_node_id.to_hash_coordinate(),
            opaque_record_key.to_hash_coordinate(),
            &peers,
        ) {
            Ok(v) => v,
            Err(e) => {
                return Ok(NetworkResult::invalid_message(format!(
                    "missing cryptosystem in peers node ids: {}",
                    e
                )));
            }
        };
        if !valid {
            return Ok(NetworkResult::invalid_message("non-closer peers returned"));
        }

        #[cfg(feature = "verbose-tracing")]
        tracing::Span::current().record("ret.latency", answer_context.latency.as_u64());
        #[cfg(feature = "verbose-tracing")]
        tracing::Span::current().record("ret.accepted", accepted);
        #[cfg(feature = "verbose-tracing")]
        if let Some(value) = &value {
            tracing::Span::current().record("ret.value.data.len", value.value_data().data().len());
            tracing::Span::current().record(
                "ret.value.data.seq",
                tracing::field::display(value.value_data().seq()),
            );
            tracing::Span::current().record(
                "ret.value.data.writer",
                tracing::field::display(value.value_data().writer()),
            );
        }
        #[cfg(feature = "verbose-tracing")]
        tracing::Span::current().record("ret.peers.len", peers.len());

        Ok(NetworkResult::value(Answer::new(
            answer_context,
            GetValueAnswer {
                accepted,
                value,
                peers,
                descriptor,
            },
        )))
    }

    ////////////////////////////////////////////////////////////////////////////////////////////////

    #[cfg_attr(feature = "instrument", instrument(level = "trace", target = "rpc", skip(self, msg), fields(msg.operation.op_id), ret, err))]
    pub(super) async fn process_get_value_q(&self, msg: Message) -> RPCNetworkResult<()> {
        // Ensure this never came over a private route, safety route is okay though
        if msg.header.is_private_routed() {
            return Ok(NetworkResult::invalid_message(
                "not processing get value request over private route",
            ));
        }
        let routing_table = self.routing_table();
        let routing_domain = msg.header.routing_domain();

        // Ignore if disabled
        let has_capability_dht = routing_table
            .get_published_peer_info(msg.header.routing_domain())
            .map(|ppi| ppi.node_info().has_capability(VEILID_CAPABILITY_DHT))
            .unwrap_or(false);
        if !has_capability_dht {
            return Ok(NetworkResult::service_unavailable("dht is not available"));
        }

        // Get the question
        let kind = msg.operation.kind().clone();
        let get_value_q = match kind {
            RPCOperationKind::Question(q) => match q.destructure() {
                (_, RPCQuestionDetail::GetValueQ(q)) => q,
                _ => panic!("not a getvalue question"),
            },
            _ => panic!("not a question"),
        };

        // Destructure
        let (opaque_record_key, subkey, want_descriptor) = get_value_q.destructure();

        // Get the nodes that we know about that are closer to the the key than our own node
        let closer_to_key_peers = network_result_try!(routing_table
            .get_reliable_nodes_closer_to_key_peer_info(
                routing_domain,
                opaque_record_key.to_hash_coordinate(),
                vec![VEILID_CAPABILITY_DHT]
            ));

        if debug_target_enabled!("dht") {
            let debug_string = format!(
                "IN <=== GetValueQ({} #{}{}) <== {}",
                opaque_record_key,
                subkey,
                if want_descriptor { " +wantdesc" } else { "" },
                msg.header.direct_sender_node_id()
            );

            veilid_log!(self debug target: "dht", "{}", debug_string);
        }

        // See if this is within the consensus width
        let consensus_width = self.config().network.dht.consensus_width as usize;
        let (accepted, get_result_value, get_result_descriptor) =
            if closer_to_key_peers.len() >= consensus_width {
                // Not close enough
                (false, None, None)
            } else {
                // Close enough, lets get it

                // See if we have this record ourselves
                let storage_manager = self.storage_manager();
                let inbound_get_value_result = network_result_try!(storage_manager
                    .inbound_get_value(&opaque_record_key, subkey, want_descriptor)
                    .await
                    .map_err(RPCError::internal)?);

                match inbound_get_value_result {
                    InboundGetValueResult::Success(get_result) => {
                        (true, get_result.opt_value, get_result.opt_descriptor)
                    }
                }
            };

        if debug_target_enabled!("dht") {
            let debug_string_value = get_result_value
                .as_ref()
                .map(|v| v.to_string())
                .unwrap_or_default();

            let debug_string_answer = format!(
                "IN ===> GetValueA({} #{}{}{}{} peers={}) ==> {}",
                opaque_record_key,
                subkey,
                debug_string_value,
                if accepted { " +accept" } else { "" },
                if get_result_descriptor.is_some() {
                    " +desc"
                } else {
                    ""
                },
                closer_to_key_peers.len(),
                msg.header.direct_sender_node_id()
            );

            veilid_log!(self debug target: "dht", "{}", debug_string_answer);
        }

        // Make GetValue answer
        let get_value_a = RPCOperationGetValueA::new(
            accepted,
            get_result_value.map(|x| (*x).clone()),
            closer_to_key_peers,
            get_result_descriptor.map(|x| (*x).clone()),
        )?;

        // Send GetValue answer
        self.answer(
            msg,
            RPCAnswer::new(RPCAnswerDetail::GetValueA(Box::new(get_value_a))),
            None,
        )
        .await
    }
}