// SPDX-FileCopyrightText: Copyright (c) 2025 NVIDIA CORPORATION & AFFILIATES. All rights reserved.
// SPDX-License-Identifier: Apache-2.0
//
// 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 triton_distributed_runtime::{
    pipeline::network::Ingress, protocols::Endpoint, DistributedRuntime, Runtime,
};
use triton_distributed_llm::http::service::discovery::ModelEntry;

use crate::{EngineConfig, ENDPOINT_SCHEME};

pub async fn run(
    runtime: Runtime,
    path: String,
    engine_config: EngineConfig,
) -> anyhow::Result<()> {
    // This will attempt to connect to NATS and etcd
    let distributed = DistributedRuntime::from_settings(runtime.clone()).await?;

    match engine_config {
        EngineConfig::StaticFull {
            service_name,
            engine,
        } => {
            let cancel_token = runtime.primary_token().clone();
            let elements: Vec<&str> = path.split('/').collect();
            if elements.len() != 3 {
                anyhow::bail!("An endpoint URL must have format {ENDPOINT_SCHEME}namespace/component/endpoint");
            }

            // Register with etcd
            let endpoint = Endpoint {
                namespace: elements[0].to_string(),
                component: elements[1].to_string(),
                name: elements[2].to_string(),
            };
            let model_registration = ModelEntry {
                name: service_name.to_string(),
                endpoint,
            };
            let etcd_client = distributed.etcd_client();
            etcd_client
                .kv_create(
                    path.clone(),
                    serde_json::to_vec_pretty(&model_registration)?,
                    None,
                )
                .await?;

            // Start the model
            let ingress = Ingress::for_engine(engine)?;
            let rt_fut = distributed
                .namespace(elements[0])?
                .component(elements[1])?
                .service_builder()
                .create()
                .await?
                .endpoint(elements[2])
                .endpoint_builder()
                .handler(ingress)
                .start();
            tokio::select! {
                _ = rt_fut => {
                    tracing::debug!("Endpoint ingress ended");
                }
                _ = cancel_token.cancelled() => {
                }
            }
            Ok(())
        }
        EngineConfig::Dynamic(_) => {
            anyhow::bail!("Cannot use endpoint for both in and out");
        }
    }
}