// SPDX-License-Identifier: GPL-3.0-only

//! `/pipeline/{stage}/backend/list` — the backends that can fill a stage.

//!

//! The slot itself is [`super::stage`], one level up: it reports the backend

//! filling the position and selects one. This is the menu that selection

//! accepts.

//!

//! Asked rather than derived. The app holds the whole `/backend/list` catalog

//! and could filter it on each model\'s role — it did — but that is a second

//! implementation of the rule `POST /pipeline/{stage}` enforces, and a picker

//! built from a filter that drifts offers a backend the daemon then refuses.

use crate::daemon::client::internal::response::require_success;

use crate::daemon::client::internal::session::with_settings_token;

use super_stt_shared::daemon::http_client::HttpResult;

use super_stt_shared::daemon::http_client::transport;

use crate::daemon::backends::BackendInfo;

/// The backends that can fill `stage`, each carrying only the models it can run

/// there (HTTP `GET /pipeline/{stage}/backend/list`).

///

/// Narrowed on both axes by the daemon, so a picker renders straight from it:

/// which backends, and which of their models.

pub async fn list_stage_backends(stage: u32) -> HttpResult<Vec<BackendInfo>> {

    with_settings_token(move |socket, token| async move {

        let path = format!("/pipeline/{stage}/backend/list");

        let resp = require_success(

            transport::settings_get(socket, &token, &path).await?,

            "list_stage_backends",

        )?;

        Ok(resp

            .backends

            .and_then(|v| serde_json::from_value(v).ok())

            .unwrap_or_default())

    })

    .await

}