// Copyright 2024 RustFS Team
//
// 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.

use crate::rpc::{TONIC_RPC_PREFIX, gen_signature_headers};
use http::Method;
use rustfs_common::GLOBAL_CONN_MAP;
use rustfs_protos::{create_new_channel, proto_gen::node_service::node_service_client::NodeServiceClient};
use std::error::Error;
use tonic::{service::interceptor::InterceptedService, transport::Channel};
use tracing::debug;

/// 3. Subsequent calls will attempt fresh connections
/// 4. If node is still down, connection will fail fast (3s timeout)
pub async fn node_service_time_out_client(
    addr: &String,
    interceptor: TonicInterceptor,
) -> Result<NodeServiceClient<InterceptedService<Channel, TonicInterceptor>>, Box<dyn Error>> {
    // Try to get cached channel
    let cached_channel = { GLOBAL_CONN_MAP.read().await.get(addr).cloned() };

    let channel = match cached_channel {
        Some(channel) => {
            debug!("Using cached gRPC channel for: {}", addr);
            channel
        }
        None => {
            // No cached connection, create new one
            create_new_channel(addr).await?
        }
    };

    Ok(NodeServiceClient::with_interceptor(channel, interceptor))
}

pub async fn node_service_time_out_client_no_auth(
    addr: &String,
) -> Result<NodeServiceClient<InterceptedService<Channel, TonicInterceptor>>, Box<dyn Error>> {
    node_service_time_out_client(addr, TonicInterceptor::NoOp(NoOpInterceptor)).await
}

pub struct TonicSignatureInterceptor;

impl tonic::service::Interceptor for TonicSignatureInterceptor {
    fn call(&mut self, mut req: tonic::Request<()>) -> Result<tonic::Request<()>, tonic::Status> {
        let headers = gen_signature_headers(TONIC_RPC_PREFIX, &Method::GET);
        req.metadata_mut().as_mut().extend(headers);
        Ok(req)
    }
}

pub fn gen_tonic_signature_interceptor() -> TonicSignatureInterceptor {
    TonicSignatureInterceptor
}

pub struct NoOpInterceptor;

impl tonic::service::Interceptor for NoOpInterceptor {
    fn call(&mut self, req: tonic::Request<()>) -> Result<tonic::Request<()>, tonic::Status> {
        Ok(req)
    }
}

pub enum TonicInterceptor {
    Signature(TonicSignatureInterceptor),
    NoOp(NoOpInterceptor),
}

impl tonic::service::Interceptor for TonicInterceptor {
    fn call(&mut self, req: tonic::Request<()>) -> Result<tonic::Request<()>, tonic::Status> {
        match self {
            TonicInterceptor::Signature(interceptor) => interceptor.call(req),
            TonicInterceptor::NoOp(interceptor) => interceptor.call(req),
        }
    }
}