//! Container lifecycle endpoints for the dashboard.
//!
//! Rebuild / restart / start / stop (hard + graceful) / update-all all
//! submit DAGs to the job queue (`job_queue::submit`), so each shows a
//! visible queued→running transient on the dashboard — a direct
//! sub-second start/stop only flashed the badge. Start/stop also
//! persist the agent's `wanted` power intent before submitting; the
//! DAG's `Reconcile` converges to it. Destroy delegates to
//! `actions::destroy` (optionally purging).

use axum::{
    extract::{Form, Path as AxumPath, Query, State},
    http::StatusCode,
    response::{IntoResponse, Response},
};
use serde::Deserialize;
use utoipa::{IntoParams, ToSchema};

/// Query params for `post_kill` / `post_restart`. `?graceful=1` routes to
/// the graceful-stop/-restart orchestration (quiesce the harness, flush
/// `/state`, then container stop/restart) instead of an immediate hard
/// action. Defaults false → today's hard kill/restart.
#[derive(Deserialize, IntoParams)]
pub(super) struct GracefulParams {
    #[serde(default)]
    graceful: bool,
}

use super::{AppState, Ident, error_response, guard_agent_name, strip_container_prefix};
use crate::job_queue::{Source, submit};
use crate::{actions, lifecycle};

/// `POST /api/rebuild/{name}` — queue a rebuild DAG for `name`.
#[utoipa::path(
    post,
    path = "/api/rebuild/{name}",
    params(("name" = String, Path, description = "agent name")),
    responses(
        (status = 200, description = "rebuild queued", body = String),
        (status = 400, description = "bad agent name"),
        (status = 404, description = "no such agent"),
    ),
    tag = "lifecycle_ops"
)]
pub(super) async fn post_rebuild(
    State(state): State<AppState>,
    AxumPath(name): AxumPath<String>,
) -> Response {
    let logical = strip_container_prefix(&name);
    if let Some(reject) = guard_agent_name(&state, &logical).await {
        return reject;
    }
    submit::rebuild(
        &state.coord,
        &logical,
        Source::Manual,
        "manual via dashboard ↻ R3BU1LD button".to_owned(),
    );
    (StatusCode::OK, "ok").into_response()
}

/// `POST /api/kill/{name}?graceful=1` — stop `name`, hard by default or
/// gracefully (quiesce → drain → stop) when `graceful=1`.
#[utoipa::path(
    post,
    path = "/api/kill/{name}",
    params(
        ("name" = String, Path, description = "agent name"),
        GracefulParams,
    ),
    responses(
        (status = 200, description = "stop queued/performed", body = String),
        (status = 400, description = "bad agent name"),
        (status = 404, description = "no such agent"),
    ),
    tag = "lifecycle_ops"
)]
pub(super) async fn post_kill(
    State(state): State<AppState>,
    AxumPath(name): AxumPath<String>,
    Query(params): Query<GracefulParams>,
) -> Response {
    let logical = strip_container_prefix(&name);
    if let Some(reject) = guard_agent_name(&state, &logical).await {
        return reject;
    }
    if params.graceful {
        // Graceful stop: submit the quiesce DAG (signal the harness →
        // one stop-checkpoint turn → drain → container stop, with a
        // timeout fallback to a hard stop). The agent's lifecycle
        // lease keeps it from racing an in-flight rebuild for the same
        // agent, and per-node progress surfaces on the queue snapshot.
        submit::graceful_stop(
            &state.coord,
            &logical,
            Source::Manual,
            "manual via dashboard graceful stop".to_owned(),
        )
        .await;
        return (StatusCode::OK, "ok").into_response();
    }
    // Manager is stoppable from the dashboard like any other
    // agent. The host's dashboard server keeps running (it's
    // hive-c0re, not the manager container), per-agent approvals
    // submitted by other sub-agents still process through the
    // host-side approval queue without the manager up, and
    // operator-driven meta-input updates work from the dashboard
    // either way. The MCP-surface self-kill guard in
    // `socket_server.rs::Request::Kill` stays in place: a
    // manager calling Kill on its own container is self-suicide
    // mid-call, not a legitimate operator action.
    submit::stop(
        &state.coord,
        &logical,
        Source::Manual,
        "manual via dashboard stop".to_owned(),
    )
    .await;
    (StatusCode::OK, "ok").into_response()
}

/// `POST /api/restart/{name}?graceful=1` — restart `name`, hard by default
/// or gracefully (quiesce → drain → restart) when `graceful=1`.
#[utoipa::path(
    post,
    path = "/api/restart/{name}",
    params(
        ("name" = String, Path, description = "agent name"),
        GracefulParams,
    ),
    responses(
        (status = 200, description = "restart queued/performed", body = String),
        (status = 400, description = "bad agent name"),
        (status = 404, description = "no such agent"),
    ),
    tag = "lifecycle_ops"
)]
pub(super) async fn post_restart(
    State(state): State<AppState>,
    AxumPath(name): AxumPath<String>,
    Query(params): Query<GracefulParams>,
) -> Response {
    let logical = strip_container_prefix(&name);
    if let Some(reject) = guard_agent_name(&state, &logical).await {
        return reject;
    }
    if params.graceful {
        submit::graceful_restart(
            &state.coord,
            &logical,
            Source::Manual,
            "manual via dashboard graceful restart".to_owned(),
        )
        .await;
        return (StatusCode::OK, "ok").into_response();
    }
    submit::restart(
        &state.coord,
        &logical,
        Source::Manual,
        "manual via dashboard ↺ R3START button".to_owned(),
    )
    .await;
    (StatusCode::OK, "ok").into_response()
}

/// Query params for `post_start`. `?paused=1` writes the pause marker
/// before (or instead of) starting — see `post_start`'s doc.
#[derive(Deserialize, IntoParams)]
pub(super) struct StartParams {
    #[serde(default)]
    paused: bool,
}

/// `POST /api/start/{name}?paused=1` — start `name`, optionally paused.
///
/// Plain `?paused=1` mirrors `hivectl agent <name> start --paused`: if
/// `name` is already running, this just writes the pause marker in place
/// and returns without submitting a start DAG (nothing to start). If it's
/// down, the marker is written *before* the start DAG is submitted, so
/// the container comes up paused rather than racing the harness's own
/// pause-gate poll against an already-in-flight start.
#[utoipa::path(
    post,
    path = "/api/start/{name}",
    params(
        ("name" = String, Path, description = "agent name"),
        StartParams,
    ),
    responses(
        (status = 200, description = "start queued (or paused in place)", body = String),
        (status = 400, description = "bad agent name"),
        (status = 404, description = "no such agent"),
        (status = 500, description = "pause marker write failed"),
    ),
    tag = "lifecycle_ops"
)]
pub(super) async fn post_start(
    State(state): State<AppState>,
    AxumPath(name): AxumPath<String>,
    Query(params): Query<StartParams>,
) -> Response {
    let logical = strip_container_prefix(&name);
    if let Some(reject) = guard_agent_name(&state, &logical).await {
        return reject;
    }
    if params.paused {
        let ident = match Ident::parse(&logical) {
            Ok(i) => i,
            Err(e) => {
                return (StatusCode::BAD_REQUEST, format!("bad agent name: {e}")).into_response();
            }
        };
        let already_running = lifecycle::is_running(&logical).await;
        if let Err(e) = crate::coordinator::Coordinator::set_paused(&ident, true).await {
            return error_response(&format!("pause {logical}: {e}"));
        }
        state.coord.rescan_containers_and_emit().await;
        if already_running {
            // Already up — pausing in place is the whole request, no DAG
            // to submit.
            return (StatusCode::OK, "ok").into_response();
        }
    }
    submit::start(
        &state.coord,
        &logical,
        Source::Manual,
        "manual via dashboard start".to_owned(),
    )
    .await;
    (StatusCode::OK, "ok").into_response()
}

/// `POST /api/pause/{name}` — write the pause marker for `name`.
///
/// Unlike the lifecycle ops above this is not a DAG: it writes a single
/// marker file, which the harness stats at the top of its serve loop.
/// Works on stopped containers too (the marker is sticky and takes effect
/// when the container next boots). Triggers an immediate rescan so the
/// `paused` badge flips on the dashboard without waiting for the next
/// periodic sweep.
#[utoipa::path(
    post,
    path = "/api/pause/{name}",
    params(("name" = String, Path, description = "agent name")),
    responses(
        (status = 200, description = "pause marker written", body = String),
        (status = 400, description = "bad agent name"),
        (status = 404, description = "no such agent"),
        (status = 500, description = "marker write failed"),
    ),
    tag = "lifecycle_ops"
)]
pub(super) async fn post_pause(
    State(state): State<AppState>,
    AxumPath(name): AxumPath<String>,
) -> Response {
    let logical = strip_container_prefix(&name);
    if let Some(reject) = guard_agent_name(&state, &logical).await {
        return reject;
    }
    let ident = match Ident::parse(&logical) {
        Ok(i) => i,
        Err(e) => return (StatusCode::BAD_REQUEST, format!("bad agent name: {e}")).into_response(),
    };
    if let Err(e) = crate::coordinator::Coordinator::set_paused(&ident, true).await {
        return error_response(&format!("pause {logical}: {e}"));
    }
    state.coord.rescan_containers_and_emit().await;
    (StatusCode::OK, "ok").into_response()
}

/// `POST /api/resume/{name}` — remove the pause marker for `name`.
///
/// The inverse of `post_pause`. Removing a non-existent marker is a no-op
/// (idempotent). Triggers an immediate rescan so the paused badge clears.
#[utoipa::path(
    post,
    path = "/api/resume/{name}",
    params(("name" = String, Path, description = "agent name")),
    responses(
        (status = 200, description = "pause marker removed", body = String),
        (status = 400, description = "bad agent name"),
        (status = 404, description = "no such agent"),
        (status = 500, description = "marker removal failed"),
    ),
    tag = "lifecycle_ops"
)]
pub(super) async fn post_resume(
    State(state): State<AppState>,
    AxumPath(name): AxumPath<String>,
) -> Response {
    let logical = strip_container_prefix(&name);
    if let Some(reject) = guard_agent_name(&state, &logical).await {
        return reject;
    }
    let ident = match Ident::parse(&logical) {
        Ok(i) => i,
        Err(e) => return (StatusCode::BAD_REQUEST, format!("bad agent name: {e}")).into_response(),
    };
    if let Err(e) = crate::coordinator::Coordinator::set_paused(&ident, false).await {
        return error_response(&format!("resume {logical}: {e}"));
    }
    state.coord.rescan_containers_and_emit().await;
    (StatusCode::OK, "ok").into_response()
}

/// Form fields for `post_resource_limits`. Both fields are optional strings;
/// an empty value clears the per-agent override for that field, falling back
/// to the hive-wide default.
#[derive(Deserialize, Default, ToSchema)]
pub(super) struct ResourceLimitsForm {
    #[serde(default)]
    cpu_quota: String,
    #[serde(default)]
    memory_max: String,
}

/// `POST /api/resource-limits/{name}` — write per-agent CPU/memory limit
/// overrides for `name`.
///
/// An empty `cpu_quota` or `memory_max` field clears that field's override,
/// falling back to the hive-wide default. Both empty together removes the
/// agent's entry entirely. The new drop-in is written immediately — the
/// limits take effect on the next container start or restart. Triggers an
/// immediate rescan so `ContainerView.cpu_quota`/`memory_max` update on
/// the dashboard via SSE without waiting for the next periodic sweep.
#[utoipa::path(
    post,
    path = "/api/resource-limits/{name}",
    params(("name" = String, Path, description = "agent name")),
    request_body(content = ResourceLimitsForm, content_type = "application/x-www-form-urlencoded"),
    responses(
        (status = 200, description = "limits written", body = String),
        (status = 400, description = "bad agent name"),
        (status = 404, description = "no such agent"),
        (status = 422, description = "invalid cpu_quota/memory_max value"),
        (status = 500, description = "commit or drop-in write failed"),
    ),
    tag = "lifecycle_ops"
)]
pub(super) async fn post_resource_limits(
    State(state): State<AppState>,
    AxumPath(name): AxumPath<String>,
    Form(form): Form<ResourceLimitsForm>,
) -> Response {
    let logical = strip_container_prefix(&name);
    if let Some(reject) = guard_agent_name(&state, &logical).await {
        return reject;
    }
    let ident = match Ident::parse(&logical) {
        Ok(i) => i,
        Err(e) => return (StatusCode::BAD_REQUEST, format!("bad agent name: {e}")).into_response(),
    };
    let cpu_quota = if form.cpu_quota.is_empty() {
        None
    } else {
        Some(form.cpu_quota.as_str())
    };
    let memory_max = if form.memory_max.is_empty() {
        None
    } else {
        Some(form.memory_max.as_str())
    };
    if let Some(v) = cpu_quota
        && let Err(e) = crate::resource_limits::validate_cpu_quota(v)
    {
        return (StatusCode::UNPROCESSABLE_ENTITY, e).into_response();
    }
    if let Some(v) = memory_max
        && let Err(e) = crate::resource_limits::validate_memory_max(v)
    {
        return (StatusCode::UNPROCESSABLE_ENTITY, e).into_response();
    }
    let limits = crate::resource_limits::AgentLimits {
        cpu_quota: cpu_quota.map(str::to_owned),
        memory_max: memory_max.map(str::to_owned),
    };
    if let Err(e) = crate::meta::commit_resource_limits(ident.as_str(), &limits).await {
        return error_response(&format!("set limits {logical}: {e:#}"));
    }
    let agent_dir = crate::paths::agent_runtime_dir(ident.as_str());
    let hive = state.coord.hive_env();
    let paths = crate::coordinator::Coordinator::agent_paths(ident.as_str(), agent_dir);
    if let Err(e) = crate::lifecycle::write_dropins(ident.as_str(), &hive, &paths).await {
        return error_response(&format!("write_dropins {logical}: {e:#}"));
    }
    state.coord.rescan_containers_and_emit().await;
    (StatusCode::OK, "ok").into_response()
}

/// `POST /api/update-all` — queue a rebuild DAG for every live agent
/// container.
#[utoipa::path(
    post,
    path = "/api/update-all",
    responses((status = 200, description = "rebuilds queued", body = String)),
    tag = "lifecycle_ops"
)]
pub(super) async fn post_update_all(State(state): State<AppState>) -> Response {
    let containers = lifecycle::list().await.unwrap_or_default();
    for container in containers {
        let Some(logical) = container
            .strip_prefix(lifecycle::AGENT_PREFIX)
            .map(str::to_owned)
        else {
            continue;
        };
        submit::rebuild(
            &state.coord,
            &logical,
            Source::Manual,
            "manual via dashboard 🌀 UPDATE ALL".to_owned(),
        );
    }
    (StatusCode::OK, "ok").into_response()
}

#[derive(Deserialize, Default, ToSchema)]
pub(super) struct DestroyForm {
    #[serde(default)]
    purge: Option<String>,
}

/// `POST /api/destroy/{name}` — destroy `name`'s container. Form field
/// `purge` (any non-empty value, e.g. `"on"`) also wipes the retained
/// state dir instead of leaving a tombstone.
#[utoipa::path(
    post,
    path = "/api/destroy/{name}",
    params(("name" = String, Path, description = "agent name")),
    request_body(content = DestroyForm, content_type = "application/x-www-form-urlencoded"),
    responses(
        (status = 200, description = "destroyed", body = String),
        (status = 400, description = "bad agent name"),
        (status = 404, description = "no such agent"),
        (status = 500, description = "destroy failed"),
    ),
    tag = "lifecycle_ops"
)]
pub(super) async fn post_destroy(
    State(state): State<AppState>,
    AxumPath(name): AxumPath<String>,
    Form(form): Form<DestroyForm>,
) -> Response {
    if let Some(reject) = guard_agent_name(&state, &name).await {
        return reject;
    }
    // Checkbox semantics: any non-empty value (axum sends "on") = purge.
    let purge = form.purge.as_deref().is_some_and(|v| !v.is_empty());
    // `actions::destroy` rescans the container list on success, so the
    // `ContainerRemoved` event lands before we return 200. The matching
    // form carries `data-no-refresh`.
    match actions::destroy(&state.coord, &name, purge).await {
        Ok(()) => (StatusCode::OK, "ok").into_response(),
        Err(e) => error_response(&format!("destroy {name} failed: {e:#}")),
    }
}