{{!

  Copyright (c) Meta Platforms, Inc. and affiliates.

  Licensed under the Apache License, Version 2.0 (the "License");
  you may not use this file except in compliance with the License.
  You may obtain a copy of the License at

      http://www.apache.org/licenses/LICENSE-2.0

  Unless required by applicable law or agreed to in writing, software
  distributed under the License is distributed on an "AS IS" BASIS,
  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  See the License for the specific language governing permissions and
  limitations under the License.

}}

{{#service:interactions?}}{{!
}}pub mod {{service:snake}} {{>lib/block}}
    use super::*;

    {{#service:interactions}}
    {{>lib/server}}
    {{/service:interactions}}

}
{{/service:interactions?}}

{{^service:interaction?}}
{{>lib/server_trait}}
{{/service:interaction?}}

/// Processor for {{service:rust_name}}'s methods.
#[derive(Clone, Debug)]
pub struct {{service:rust_name}}Processor<P, H, R, RS{{!
    }}{{#service:extends?}}, SS{{/service:extends?}}{{!
    }}{{!
}}> {
    service: H,{{!
    }}{{#service:extends?}}
    supa: SS,{{!
    }}{{/service:extends?}}{{!
    }}{{^service:extends?}}
    supa: ::fbthrift::NullServiceProcessor<P, R, RS>,{{!
    }}{{/service:extends?}}
    _phantom: ::std::marker::PhantomData<(P, H, R, RS)>,
}

{{^service:interaction?}}
{{>lib/server_arg}}
{{/service:interaction?}}
impl<P, H, R, RS{{!
    }}{{#service:extends?}}, SS{{/service:extends?}}{{!
}}> {{service:rust_name}}Processor<P, H, R, RS{{!
    }}{{#service:extends?}}, SS{{/service:extends?}}{{!
}}>
where
    P: ::fbthrift::Protocol + ::std::marker::Send + ::std::marker::Sync + 'static,
    P::Frame: ::std::marker::Send + 'static,
    P::Deserializer: ::std::marker::Send,
    H: {{service:rust_name}}{{!
    }}{{#service:requestContext?}}<RequestContext = R>{{/service:requestContext?}},
    R: ::fbthrift::RequestContext<Name = ::std::ffi::CStr> + ::std::marker::Send + ::std::marker::Sync + 'static,
    RS: ::fbthrift::ReplyState<P::Frame, RequestContext = R> + ::std::marker::Send + ::std::marker::Sync + 'static,
    <R as ::fbthrift::RequestContext>::ContextStack: ::fbthrift::ContextStack<Name = R::Name, Frame = <P as ::fbthrift::Protocol>::Frame>
        + ::std::marker::Send + ::std::marker::Sync,
    ::fbthrift::ProtocolDecoded<P>: ::std::clone::Clone,
    ::fbthrift::ProtocolEncodedFinal<P>: ::std::clone::Clone + ::fbthrift::BufExt,{{!
    }}{{#service:extends?}}
    SS: ::fbthrift::ThriftService<P::Frame>,
    SS::Handler: {{>lib/super}}{{!
    }}{{/service:extends?}}
{
    pub fn new({{!
        }}service: H{{!
        }}{{#service:extends?}}, supa: SS{{/service:extends?}}{{!
    }}) -> Self {
        Self {
            service,
            supa{{^service:extends?}}{{!
                }}: ::fbthrift::NullServiceProcessor::new(){{!
            }}{{/service:extends?}},
            _phantom: ::std::marker::PhantomData,
        }
    }

    pub fn into_inner(self) -> H {
        self.service
    }{{!
    }}{{#service:rustFunctions}}{{^function:starts_interaction?}}{{^function:sink?}}

    #[::tracing::instrument(skip_all, name = "handler", fields(method = "{{service:name}}.{{function:name}}"))]
    async fn handle_{{function:name}}<'a>(
        &'a self,
        p: &'a mut P::Deserializer,
        req: ::fbthrift::ProtocolDecoded<P>,
        req_ctxt: &R,
        reply_state: ::std::sync::Arc<RS>,
        _seqid: ::std::primitive::u32,
    ) -> ::anyhow::Result<()> {
        use ::futures::FutureExt as _;

        const SERVICE_NAME: &::std::ffi::CStr = c"{{service:parent_service_name}}";
        const METHOD_NAME: &::std::ffi::CStr = c"{{#service:interaction?}}{{service:name}}.{{/service:interaction?}}{{function:name}}";
        const SERVICE_METHOD_NAME: &::std::ffi::CStr = c"{{service:parent_service_name}}.{{#service:interaction?}}{{service:name}}.{{/service:interaction?}}{{function:name}}";
        let mut ctx_stack = req_ctxt.get_context_stack(SERVICE_NAME, SERVICE_METHOD_NAME)?;
        ::fbthrift::ContextStack::pre_read(&mut ctx_stack)?;
        let _args: self::Args_{{service:rust_name}}_{{function:name}} = ::fbthrift::Deserialize::read(p)?;
        let bytes_read = ::fbthrift::help::buf_len(&req)?;
        ::fbthrift::ContextStack::on_read_data(&mut ctx_stack, ::fbthrift::SerializedMessage {
            protocol: P::PROTOCOL_ID,
            method_name: METHOD_NAME,
            buffer: req,
        })?;
        ::fbthrift::ContextStack::post_read(&mut ctx_stack, bytes_read)?;

        let res = ::std::panic::AssertUnwindSafe(
            self.service.{{function:rust_name}}({{!
                }}{{#service:requestContext?}}
                req_ctxt,{{!
                }}{{/service:requestContext?}}{{!
                }}{{#function:args}}
                _args.{{field:rust_name}},{{!
                }}{{/function:args}}
            )
        )
        .catch_unwind()
        .await;

        // nested results - panic catch on the outside, method on the inside
        let res = match res {
            ::std::result::Result::Ok(::std::result::Result::Ok(res)) => {
                ::tracing::trace!(method = "{{service:name}}.{{function:name}}", "success");
                {{#function:creates_interaction?}}
                {{#function:return_type}}{{#type:void?}}
                let (interaction_handler, res) = (res, ());
                {{/type:void?}}{{^type:void?}}
                let (interaction_handler, res) = res;
                {{/type:void?}}{{/function:return_type}}
                let interaction_processor = ::std::sync::Arc::new({{program:crate}}::server::{{service:snake}}::{{function:interaction_name}}Processor::<P, ::std::boxed::Box<dyn {{function:interaction_name}}>, R, RS>::new(interaction_handler));
                reply_state.set_interaction_processor(interaction_processor)?;
                {{/function:creates_interaction?}}
                ::std::result::Result::Ok(res)
            }
            ::std::result::Result::Ok(::std::result::Result::Err(exn)) => {
                {{!TODO: Remove this once debug for stream is implemented.}}
                {{^function:stream?}}
                ::tracing::error!(method = "{{service:name}}.{{function:name}}", exception = ?exn);
                {{/function:stream?}}
                ::std::result::Result::Err(exn)
            }
            ::std::result::Result::Err(exn) => {
                let aexn = ::fbthrift::ApplicationException::handler_panic("{{service:name}}.{{function:name}}", exn);
                ::tracing::error!(method = "{{service:name}}.{{function:name}}", panic = ?aexn);
                ::std::result::Result::Err({{program:crate}}::services::{{service:snake}}::{{function:upcamel}}Exn::ApplicationException(aexn))
            }
        };
        {{^function:stream?}}

        let env = ::fbthrift::help::serialize_result_envelope::<P, R, {{program:crate}}::services::{{service:snake}}::{{function:upcamel}}Exn>(
            "{{function:name}}",
            METHOD_NAME,
            _seqid,
            req_ctxt,
            &mut ctx_stack,
            res,
        )?;
        reply_state.send_reply(env);
        ::std::result::Result::Ok(())
        {{/function:stream?}}
        {{#function:stream?}}

        use ::futures::StreamExt as _;

        let (response, stream) = match res {
            ::std::result::Result::Ok(res) => {
                {{#function:stream_has_first_response?}}
                let (response, stream) = res;
                let response = ::std::result::Result::Ok(response);
                {{/function:stream_has_first_response?}}{{!
                }}{{^function:stream_has_first_response?}}
                let response = ::std::result::Result::Ok(());
                let stream = res;
                {{/function:stream_has_first_response?}}

                let stream = ::std::panic::AssertUnwindSafe(stream)
                    .catch_unwind()
                    .map(|item| {
                        match item {
                            ::std::result::Result::Ok(::std::result::Result::Ok(success)) => {
                                let payload = ::fbthrift::help::serialize_stream_item::<P, {{program:crate}}::services::{{service:snake}}::{{function:upcamel}}StreamExn>(
                                    ::std::result::Result::Ok(success),
                                    "{{function:name}}",
                                );
                                ::fbthrift::SerializedStreamElement::Success(payload)
                            }
                            ::std::result::Result::Ok(::std::result::Result::Err({{program:crate}}::services::{{service:snake}}::{{function:upcamel}}StreamExn::ApplicationException(aexn))) => {
                                tracing::info!(?aexn, method="{{service:name}}.{{function:name}}", "Streaming ApplicationException");
                                ::fbthrift::SerializedStreamElement::ApplicationException(aexn)
                            }
                            {{#function:stream_exceptions?}}
                            ::std::result::Result::Ok(::std::result::Result::Err(exn)) => {
                                tracing::debug!(?exn, method="{{service:name}}.{{function:name}}", "Streaming declared exception");
                                let payload = ::fbthrift::help::serialize_stream_item::<P, {{program:crate}}::services::{{service:snake}}::{{function:upcamel}}StreamExn>(
                                    ::std::result::Result::Err(exn),
                                    "{{function:name}}",
                                );
                                ::fbthrift::SerializedStreamElement::DeclaredException(payload)
                            }
                            {{/function:stream_exceptions?}}
                            ::std::result::Result::Err(exn) => {
                                tracing::error!(?exn, method="{{service:name}}.{{function:name}}", "Streaming unwind");
                                let aexn = ::fbthrift::ApplicationException::handler_panic("{{service:name}}.{{function:name}}", exn);
                                ::fbthrift::SerializedStreamElement::ApplicationException(aexn)
                            }
                        }
                    })
                    {{!TODO(T125947234): should we instrument with tracing?}}
                    .boxed();
                (response, ::std::option::Option::Some(stream))
            },
            ::std::result::Result::Err(exn) => (::std::result::Result::Err(exn), ::std::option::Option::None),
        };

        let response = ::fbthrift::help::serialize_result_envelope::<P, R, {{program:crate}}::services::{{service:snake}}::{{function:upcamel}}Exn>(
            "{{function:name}}",
            METHOD_NAME,
            _seqid,
            req_ctxt,
            &mut ctx_stack,
            response,
        )?;

        let _ = reply_state.send_stream_reply(response, stream, P::PROTOCOL_ID);
        ::std::result::Result::Ok(())
        {{/function:stream?}}
    }{{!
    }}{{/function:sink?}}{{/function:starts_interaction?}}{{#function:starts_interaction?}}

    fn handle_{{function:name}}(
        &self,
    ) -> ::anyhow::Result<::std::boxed::Box<dyn {{function:interaction_name}}>> {
        self.service.{{function:rust_name}}()
    }{{!
    }}{{/function:starts_interaction?}}{{!
    }}{{/service:rustFunctions}}
}

#[::async_trait::async_trait]
impl<P, H, R, RS{{!
    }}{{#service:extends?}}, SS{{/service:extends?}}{{!
}}> ::fbthrift::ServiceProcessor<P> for {{service:rust_name}}Processor<P, H, R, RS{{!
    }}{{#service:extends?}}, SS{{/service:extends?}}{{!
}}>
where
    P: ::fbthrift::Protocol + ::std::marker::Send + ::std::marker::Sync + 'static,
    P::Deserializer: ::std::marker::Send,
    H: {{service:rust_name}}{{!
    }}{{#service:requestContext?}}<RequestContext = R>{{/service:requestContext?}},{{!
    }}{{#service:extends?}}
    SS: ::fbthrift::ThriftService<P::Frame>,
    SS::Handler: {{>lib/super}},{{!
    }}{{/service:extends?}}
    P::Frame: ::std::marker::Send + 'static,
    R: ::fbthrift::RequestContext<Name = ::std::ffi::CStr> + ::std::marker::Send + ::std::marker::Sync + 'static,
    <R as ::fbthrift::RequestContext>::ContextStack: ::fbthrift::ContextStack<Name = R::Name, Frame = <P as ::fbthrift::Protocol>::Frame>
        + ::std::marker::Send + ::std::marker::Sync + 'static,
    RS: ::fbthrift::ReplyState<P::Frame, RequestContext = R> + ::std::marker::Send + ::std::marker::Sync + 'static,
    ::fbthrift::ProtocolDecoded<P>: ::std::clone::Clone,
    ::fbthrift::ProtocolEncodedFinal<P>: ::std::clone::Clone + ::fbthrift::BufExt,
{
    type RequestContext = R;
    type ReplyState = RS;

    #[inline]
    fn method_idx(&self, name: &[::std::primitive::u8]) -> ::std::result::Result<::std::primitive::usize, ::fbthrift::ApplicationException> {
        match name {{>lib/block}}{{!
            }}{{#service:rustFunctions}}{{^function:starts_interaction?}}{{^function:sink?}}
            b"{{#service:interaction?}}{{service:name}}.{{/service:interaction?}}{{function:name}}" => ::std::result::Result::Ok({{function:index}}usize),{{!
            }}{{/function:sink?}}{{/function:starts_interaction?}}{{/service:rustFunctions}}
            _ => ::std::result::Result::Err(::fbthrift::ApplicationException::unknown_method()),
        }
    }

    #[allow(clippy::match_single_binding)]
    async fn handle_method(
        &self,
        idx: ::std::primitive::usize,
        _p: &mut P::Deserializer,
        _req: ::fbthrift::ProtocolDecoded<P>,
        _req_ctxt: &R,
        _reply_state: ::std::sync::Arc<RS>,
        _seqid: ::std::primitive::u32,
    ) -> ::anyhow::Result<()> {
        match idx {{>lib/block}}{{!
            }}{{#service:rustFunctions}}{{^function:starts_interaction?}}{{^function:sink?}}
            {{function:index}}usize => {
                self.handle_{{function:name}}(_p, _req, _req_ctxt, _reply_state, _seqid).await
            }{{!
            }}{{/function:sink?}}{{/function:starts_interaction?}}{{/service:rustFunctions}}
            bad => panic!(
                "{}: unexpected method idx {}",
                "{{service:rust_name}}Processor",
                bad
            ),
        }
    }

    #[allow(clippy::match_single_binding)]
    #[inline]
    fn create_interaction_idx(&self, name: &::std::primitive::str) -> ::anyhow::Result<::std::primitive::usize> {
        match name {{>lib/block}}{{!
            }}{{#service:rustFunctions}}{{#function:starts_interaction?}}
            "{{function:interaction_name}}" => ::std::result::Result::Ok({{function:index}}usize),{{!
            }}{{/function:starts_interaction?}}{{/service:rustFunctions}}
            _ => ::anyhow::bail!("Unknown interaction"),
        }
    }

    #[allow(clippy::match_single_binding)]
    fn handle_create_interaction(
        &self,
        idx: ::std::primitive::usize,
    ) -> ::anyhow::Result<
        ::std::sync::Arc<dyn ::fbthrift::ThriftService<P::Frame, Handler = (), RequestContext = Self::RequestContext, ReplyState = Self::ReplyState> + ::std::marker::Send + 'static>
    > {
        match idx {{>lib/block}}{{!
            }}{{#service:rustFunctions}}{{#function:starts_interaction?}}
            {{function:index}}usize => {
                let handler = self.handle_{{function:name}}()?;
                let server = ::std::sync::Arc::new({{program:crate}}::server::{{service:snake}}::{{function:interaction_name}}Processor::<P, ::std::boxed::Box<dyn {{function:interaction_name}}>, R, RS>::new(handler));
                ::std::result::Result::Ok(server)
            }{{!
            }}{{/function:starts_interaction?}}{{/service:rustFunctions}}
            bad => panic!(
                "{}: unexpected method idx {}",
                "{{service:rust_name}}Processor",
                bad
            ),
        }
    }

    async fn handle_on_termination(&self) {
        {{#service:interaction?}}
        self.service.on_termination().await
        {{/service:interaction?}}
    }
}

#[::async_trait::async_trait]
impl<P, H, R, RS{{!
    }}{{#service:extends?}}, SS{{/service:extends?}}{{!
}}> ::fbthrift::ThriftService<P::Frame> for {{service:rust_name}}Processor<P, H, R, RS{{!
    }}{{#service:extends?}}, SS{{/service:extends?}}{{!
}}>
where
    P: ::fbthrift::Protocol + ::std::marker::Send + ::std::marker::Sync + 'static,
    P::Deserializer: ::std::marker::Send,
    P::Frame: ::std::marker::Send + 'static,
    H: {{service:rust_name}}{{!
    }}{{#service:requestContext?}}<RequestContext = R>{{/service:requestContext?}},{{!
    }}{{#service:extends?}}
    SS: ::fbthrift::ThriftService<P::Frame, RequestContext = R, ReplyState = RS>,
    SS::Handler: {{>lib/super}},
    P::Frame: ::std::marker::Send + 'static,{{!
    }}{{/service:extends?}}
    R: ::fbthrift::RequestContext<Name = ::std::ffi::CStr> + ::std::marker::Send + ::std::marker::Sync + 'static,
    <R as ::fbthrift::RequestContext>::ContextStack: ::fbthrift::ContextStack<Name = R::Name, Frame = <P as ::fbthrift::Protocol>::Frame>
        + ::std::marker::Send + ::std::marker::Sync + 'static,
    RS: ::fbthrift::ReplyState<P::Frame, RequestContext = R> + ::std::marker::Send + ::std::marker::Sync + 'static,
    ::fbthrift::ProtocolDecoded<P>: ::std::clone::Clone,
    ::fbthrift::ProtocolEncodedFinal<P>: ::std::clone::Clone + ::fbthrift::BufExt,
{
    {{#service:interaction?}}
    // Interactions have () as their handler associated type
    // to make `create_interaction` have a common return type.
    type Handler = ();
    {{/service:interaction?}}{{^service:interaction?}}
    type Handler = H;
    {{/service:interaction?}}
    type RequestContext = R;
    type ReplyState = RS;

    #[tracing::instrument(level="trace", skip_all, fields(service = "{{service:name}}"))]
    async fn call(
        &self,
        req: ::fbthrift::ProtocolDecoded<P>,
        req_ctxt: &R,
        reply_state: ::std::sync::Arc<RS>,
    ) -> ::anyhow::Result<()> {
        use ::fbthrift::{ProtocolReader as _, ServiceProcessor as _};
        let mut p = P::deserializer(req.clone());
        let (idx, mty, seqid) = p.read_message_begin(|name| self.method_idx(name))?;
        if mty != ::fbthrift::MessageType::Call {
            return ::std::result::Result::Err(::std::convert::From::from(::fbthrift::ApplicationException::new(
                ::fbthrift::ApplicationExceptionErrorCode::InvalidMessageType,
                format!("message type {:?} not handled", mty)
            )));
        }
        let idx = match idx {
            ::std::result::Result::Ok(idx) => idx,
            ::std::result::Result::Err(_) => {
                return self.supa.call(req, req_ctxt, reply_state).await;
            }
        };
        self.handle_method(idx, &mut p, req, req_ctxt, reply_state, seqid).await?;
        p.read_message_end()?;

        ::std::result::Result::Ok(())
    }

    fn create_interaction(
        &self,
        name: &::std::primitive::str,
    ) -> ::anyhow::Result<
        ::std::sync::Arc<dyn ::fbthrift::ThriftService<P::Frame, Handler = (), RequestContext = R, ReplyState = RS> + ::std::marker::Send + 'static>
    > {
        use ::fbthrift::{ServiceProcessor as _};
        let idx = self.create_interaction_idx(name);
        let idx = match idx {
            ::anyhow::Result::Ok(idx) => idx,
            ::anyhow::Result::Err(_) => {
                return self.supa.create_interaction(name);
            }
        };
        self.handle_create_interaction(idx)
    }

    fn get_method_names(&self) -> &'static [&'static ::std::primitive::str] {
        &[
{{>lib/method_names}}
        ]
    }

    async fn on_termination(&self) {
        use ::fbthrift::{ServiceProcessor as _};
        self.handle_on_termination().await
    }
}

{{^service:interaction?}}
/// Construct a new instance of a {{service:rust_name}} service.
///
/// This is called when a new instance of a Thrift service Processor
/// is needed for a particular Thrift protocol.
#[::tracing::instrument(level="debug", skip_all, fields(proto = ?proto))]
pub fn make_{{service:rust_name}}_server<F, H, R, RS{{!
    }}{{#service:extends?}}, SMAKE, SS{{/service:extends?}}{{!
}}>(
    proto: ::fbthrift::ProtocolID,
    handler: H,{{!
    }}{{#service:extends?}}
    supa: SMAKE,{{!
    }}{{/service:extends?}}
) -> ::std::result::Result<::std::boxed::Box<dyn ::fbthrift::ThriftService<F, Handler = H, RequestContext = R, ReplyState = RS> + ::std::marker::Send + 'static>, ::fbthrift::ApplicationException>
where
    F: ::fbthrift::Framing + ::std::marker::Send + ::std::marker::Sync + 'static,
    H: {{service:rust_name}}{{!
    }}{{#service:requestContext?}}<RequestContext = R>{{/service:requestContext?}},{{!
    }}{{#service:extends?}}
    SMAKE: ::std::ops::FnOnce(::fbthrift::ProtocolID) -> ::std::result::Result<SS, ::fbthrift::ApplicationException>,
    SS: ::fbthrift::ThriftService<F, RequestContext = R, ReplyState = RS>,
    SS::Handler: {{>lib/super}},{{!
    }}{{/service:extends?}}
    R: ::fbthrift::RequestContext<Name = ::std::ffi::CStr> + ::std::marker::Send + ::std::marker::Sync + 'static,
    <R as ::fbthrift::RequestContext>::ContextStack: ::fbthrift::ContextStack<Name = R::Name, Frame = F> + ::std::marker::Send + ::std::marker::Sync + 'static,
    RS: ::fbthrift::ReplyState<F, RequestContext = R> + ::std::marker::Send + ::std::marker::Sync + 'static,
    ::fbthrift::FramingDecoded<F>: ::std::clone::Clone,
    ::fbthrift::FramingEncodedFinal<F>: ::std::clone::Clone + ::fbthrift::BufExt,
{
    match proto {
        ::fbthrift::ProtocolID::BinaryProtocol => {
            ::std::result::Result::Ok(::std::boxed::Box::new({{service:rust_name}}Processor::<::fbthrift::BinaryProtocol<F>, H, R, RS{{!
                }}{{#service:extends?}}, SS{{/service:extends?}}{{!
            }}>::new(handler{{!
                }}{{#service:extends?}}, supa(proto)?{{/service:extends?}}{{!
            }})))
        }
        ::fbthrift::ProtocolID::CompactProtocol => {
            ::std::result::Result::Ok(::std::boxed::Box::new({{service:rust_name}}Processor::<::fbthrift::CompactProtocol<F>, H, R, RS{{!
                }}{{#service:extends?}}, SS{{/service:extends?}}{{!
            }}>::new(handler{{!
                }}{{#service:extends?}}, supa(proto)?{{/service:extends?}}{{!
            }})))
        }
        bad => {
            ::tracing::error!(method = "{{service:name}}.{{function:name}}", invalid_protocol = ?bad);
            ::std::result::Result::Err(::fbthrift::ApplicationException::invalid_protocol(bad))
        }
    }
}
{{/service:interaction?}}
{{!newline}}