//! Experimental RPC support.

use anyhow::Result;

use arti_rpcserver::RpcMgr;

use derive_deftly::Deftly;

use fs_mistrust::Mistrust;

use futures::{AsyncReadExt, stream::StreamExt};

use session::ArtiRpcSession;

use std::collections::BTreeMap;

use std::{io::Result as IoResult, sync::Arc};

use tor_config::derive::prelude::*;

use tor_config_path::CfgPathResolver;

use tracing::{debug, info};

use arti_client::TorClient;

use tor_rtcompat::{NetStreamListener as _, Runtime, SpawnExt, general};

pub(crate) mod conntarget;

pub(crate) mod listener;

mod proxyinfo;

mod session;

use listener::RpcListenerSetConfig;

pub(crate) use session::{RpcStateSender, RpcVisibleArtiState};

/// Configuration for Arti's RPC subsystem.

///

/// You cannot change this section on a running Arti client.

#[derive(Debug, Clone, Deftly, Eq, PartialEq)]

#[derive_deftly(TorConfig)]

#[cfg_attr(feature = "experimental-api", visibility::make(pub))]

#[cfg_attr(feature = "experimental-api", deftly(tor_config(vis = "pub")))]

pub(crate) struct RpcConfig {

    /// If true, then the RPC subsystem is enabled and will listen for connections.

    #[deftly(tor_config(default = "false"))] // TODO RPC make this true once we are stable.

    enable: bool,

    /// A set of named locations in which to find connect files.

    #[deftly(tor_config(map, default = "listener::listener_map_defaults()"))]

    listen: BTreeMap<String, RpcListenerSetConfig>,

    /// A list of default connect points to bind

    /// if no enabled connect points are found under `listen`.

    #[deftly(tor_config(list(element(clone)), default = "listen_defaults_defaults()"))]

    listen_default: Vec<String>,

}

/// Return default values for `RpcConfig.listen_default`

/// Information about an incoming connection.

///

/// Yielded in a stream from our RPC listeners.

type IncomingConn = (

    general::Stream,

    general::SocketAddr,

    Arc<listener::RpcConnInfo>,

);

/// Bind to all configured RPC listeners in `cfg`.

///

/// On success, return a stream of `IncomingConn`.

#[allow(clippy::cognitive_complexity)] // TODO: Refactor?

        {

            // (Note that `bind` only returns enabled listeners, so we don't need to check here.

            );

        }

    }

            );

        }

/// Create an RPC manager, bind to connect points, and open a listener task to accept incoming

/// RPC connections.

    // Register methods. Needed since TorClient is generic.

    //

    // TODO: If we accumulate a large number of generics like this, we should do this elsewhere.

    // TODO: Using spawn in this way makes it hard to report whether we

    // succeeded or not. This is something we should fix when we refactor

    // our service-launching code.

/// Backend function to implement an RPC listener: runs in a loop.

    }

/// Information passed to a proxy or similar stream provider when running with RPC support.

pub(crate) struct RpcProxySupport {

    /// An RPC manager to use for looking up objects as possible stream targets.

    pub(crate) rpc_mgr: Arc<arti_rpcserver::RpcMgr>,

    /// An RPCStateSender to use for registering the list of known proxy ports.

    pub(crate) rpc_state_sender: RpcStateSender,

}

#[cfg(test)]

mod test {

    // @@ begin test lint list maintained by maint/add_warning @@

    #![allow(clippy::bool_assert_comparison)]

    #![allow(clippy::clone_on_copy)]

    #![allow(clippy::dbg_macro)]

    #![allow(clippy::mixed_attributes_style)]

    #![allow(clippy::print_stderr)]

    #![allow(clippy::print_stdout)]

    #![allow(clippy::single_char_pattern)]

    #![allow(clippy::unwrap_used)]

    #![allow(clippy::unchecked_time_subtraction)]

    #![allow(clippy::useless_vec)]

    #![allow(clippy::needless_pass_by_value)]

    //! <!-- @@ end test lint list maintained by maint/add_warning @@ -->

    use listener::{ConnectPointOptionsBuilder, RpcListenerSetConfigBuilder};

    use tor_config_path::CfgPath;

    use tor_rpc_connect::ParsedConnectPoint;

    use super::*;

    #[test]

    fn rpc_method_names() {

        // We run this from a nice high level module, to ensure that as many method names as

        // possible will be in-scope.

        let problems = tor_rpcbase::check_method_names([]);

        for (m, err) in &problems {

            eprintln!("Bad method name {m:?}: {err}");

        }

        assert!(problems.is_empty());

    }

    #[test]

    fn parse_listener_defaults() {

        for string in listen_defaults_defaults() {

            let _parsed: ParsedConnectPoint = string.parse().unwrap();

        }

    }

    #[test]

    fn parsing_and_building() {

        fn build(s: &str) -> Result<RpcConfig, anyhow::Error> {

            let b: RpcConfigBuilder = toml::from_str(s)?;

            Ok(b.build()?)

        }

        let mut user_defaults_builder = RpcListenerSetConfigBuilder::default();

        user_defaults_builder.listener_options().enable(true);

        user_defaults_builder.dir(CfgPath::new("${ARTI_LOCAL_DATA}/rpc/connect.d".to_string()));

        let mut system_defaults_builder = RpcListenerSetConfigBuilder::default();

        system_defaults_builder.listener_options().enable(false);

        system_defaults_builder.dir(CfgPath::new("/etc/arti-rpc/connect.d".to_string()));

        // Make sure that an empty configuration gets us the defaults.

        let defaults = build("").unwrap();

        assert_eq!(

            defaults,

            RpcConfig {

                enable: false,

                listen: vec![

                    (

                        "user-default".to_string(),

                        user_defaults_builder.build().unwrap()

                    ),

                    (

                        "system-default".to_string(),

                        system_defaults_builder.build().unwrap()

                    ),

                ]

                .into_iter()

                .collect(),

                listen_default: listen_defaults_defaults()

            }

        );

        // Make sure that overriding specific options works as expected.

        let altered = build(

            r#"

[listen."user-default"]

enable = false

[listen."system-default"]

dir = "/usr/local/etc/arti-rpc/connect.d"

file_options = { "tmp.toml" = { "enable" = false } }

[listen."my-connpt"]

file = "/home/dante/.paradiso/connpt.toml"

"#,

        )

        .unwrap();

        let mut altered_user_defaults = user_defaults_builder.clone();

        altered_user_defaults.listener_options().enable(false);

        let mut altered_system_defaults = system_defaults_builder.clone();

        altered_system_defaults.dir(CfgPath::new(

            "/usr/local/etc/arti-rpc/connect.d".to_string(),

        ));

        let mut opt = ConnectPointOptionsBuilder::default();

        opt.enable(false);

        altered_system_defaults

            .file_options()

            .insert("tmp.toml".to_string(), opt);

        let mut my_connpt = RpcListenerSetConfigBuilder::default();

        my_connpt.file(CfgPath::new(

            "/home/dante/.paradiso/connpt.toml".to_string(),

        ));

        assert_eq!(

            altered,

            RpcConfig {

                enable: false,

                listen: vec![

                    (

                        "user-default".to_string(),

                        altered_user_defaults.build().unwrap()

                    ),

                    (

                        "system-default".to_string(),

                        altered_system_defaults.build().unwrap()

                    ),

                    ("my-connpt".to_string(), my_connpt.build().unwrap()),

                ]

                .into_iter()

                .collect(),

                listen_default: listen_defaults_defaults()

            }

        );

    }

}