//! Hyperhive dashboard. Lists managed containers (with deep-links to each
//! container's web UI), pending approvals (with unified diff vs the applied
//! repo, plus approve/deny buttons), and the manager.

use std::net::SocketAddr;
use std::sync::Arc;

use anyhow::{Context, Result};
use axum::{
    Router,
    http::StatusCode,
    response::{IntoResponse, Response},
    routing::{get, post},
};

use crate::coordinator::Coordinator;
use crate::lifecycle;

mod approvals;
mod build_logs;
mod extra_forges;
mod idents;
pub(crate) use idents::AgentName;
mod infra_containers;
mod journal;
mod lifecycle_ops;
mod matrix_accounts;
mod meta_inputs;
mod misc_api;
pub(crate) mod permissions;
mod questions;
mod reminders;
mod schedules;
mod state_files;
mod state_snapshot;
mod tombstones;
mod topology;
mod webhook;

// Run after lock bumps by the job queue (`job_queue/exec.rs`); the view
// type feeds `DashboardEvent::MetaInputsChanged` (`dashboard_events.rs`).
// Re-exported to preserve the `crate::dashboard::*` paths across the split.
pub use meta_inputs::MetaInputView;
pub(crate) use meta_inputs::emit_meta_inputs_snapshot;
// Run at broker-message ingest by the coordinator + the operator-msg path
// (`main.rs`); re-exported to preserve the `crate::dashboard::scan_validated_paths`
// path across the split.
pub use state_files::scan_validated_paths;
// Called after destroy/purge/spawn finalisation (`actions.rs`); the view
// type feeds `DashboardEvent::TombstonesChanged` (`dashboard_events.rs`).
// Re-exported to preserve the `crate::dashboard::*` paths across the split.
pub use tombstones::TombstoneView;
pub(crate) use tombstones::emit_tombstones_snapshot;

#[derive(Clone)]
struct AppState {
    coord: Arc<Coordinator>,
    /// HMAC-SHA256 secret shared with Forgejo webhook registrations.
    /// Verified on every incoming `/webhook/*` POST.
    /// `None` when the secret could not be loaded at startup — all
    /// `/webhook/*` requests are rejected with 503 in that case.
    webhook_secret: Option<String>,
}

#[allow(
    clippy::too_many_lines,
    reason = "the body is dominated by the flat axum route table — one line \
              per endpoint mapping a URL to its (now per-concern submodule) \
              handler; splitting that exhaustive list across helpers would \
              obscure the route map for no readability gain"
)]
pub async fn serve(
    port: u16,
    coord: Arc<Coordinator>,
    webhook_secret: Option<String>,
) -> Result<()> {
    // API-only: the gateway static-serves the dashboard dist and proxies
    // non-static requests here (see hive-gateway.nix). Unmatched paths 404.
    let app = Router::new()
        .route("/api/state", get(state_snapshot::api_state))
        .route("/api/journal/{name}", get(journal::get_journal))
        .route("/api/journal-host", get(journal::get_journal_host))
        .route("/api/state-file", get(state_files::get_state_file))
        .route(
            "/api/matrix-accounts",
            get(matrix_accounts::get_matrix_accounts),
        )
        .route("/api/extra-forges", get(extra_forges::get_extra_forges))
        .route(
            "/api/extra-forge-account",
            post(extra_forges::post_extra_forge_account),
        )
        .route("/api/reminders", get(reminders::api_reminders))
        .route("/api/operator-inbox", get(misc_api::api_operator_inbox))
        .route("/api/stats-hive", get(misc_api::api_stats_hive))
        .route(
            "/api/container-resources",
            get(misc_api::api_container_resources),
        )
        .route("/api/audit-log", get(misc_api::api_audit_log))
        .route("/api/build-logs", get(build_logs::get_build_logs_all))
        .route(
            "/api/build-logs/{agent}",
            get(build_logs::get_build_logs_agent),
        )
        .route(
            "/api/build-logs/id/{id}",
            get(build_logs::get_build_log_full),
        )
        .route(
            "/api/build-logs/id/{id}/stream",
            get(build_logs::get_build_log_stream),
        )
        .route(
            "/api/build-logs/id/{id}/raw",
            get(build_logs::get_build_log_raw),
        )
        .route(
            "/api/agent/{name}/mark-all-read",
            post(misc_api::post_mark_all_read),
        )
        .route("/api/topology/set-parent", post(topology::post_set_parent))
        .route(
            "/api/topology/set-parent-bulk",
            post(topology::post_set_parent_bulk),
        )
        .route("/api/tool-groups", get(permissions::get_tool_groups))
        .route(
            "/api/tool-groups/{agent}",
            post(permissions::post_tool_groups),
        )
        .route("/api/capabilities", get(permissions::get_capabilities))
        .route(
            "/api/capabilities/{agent}",
            post(permissions::post_capabilities),
        )
        .route("/api/permissions", post(permissions::post_permissions))
        .route(
            "/api/permissions/stale",
            get(permissions::get_stale_permissions),
        )
        .route(
            "/api/permissions/{agent}",
            axum::routing::delete(permissions::delete_agent_permissions),
        )
        .route(
            "/api/schedules",
            get(schedules::api_schedules).post(schedules::post_schedule_new),
        )
        .route(
            "/api/schedules/{id}",
            axum::routing::patch(schedules::patch_schedule),
        )
        .route(
            "/api/schedules/{id}/cancel",
            post(schedules::post_schedule_cancel),
        )
        .route(
            "/api/schedules/{id}/pause",
            post(schedules::post_schedule_pause),
        )
        .route(
            "/api/schedules/{id}/resume",
            post(schedules::post_schedule_resume),
        )
        .route(
            "/api/schedules/{id}/fire-now",
            post(schedules::post_schedule_fire_now),
        )
        .route(
            "/api/rebuild-queue/{id}/cancel",
            post(schedules::post_rebuild_queue_cancel),
        )
        .route("/webhook/knowledge", post(webhook::post_webhook_knowledge))
        .route("/webhook/config-pr", post(webhook::post_webhook_config_pr))
        // Backend routes — the frontend calls these `/api/` paths. The
        // transitional bare top-level aliases were removed once the
        // frontend migrated. `/webhook/*` keeps its own prefix
        // (forge-driven, not the SPA).
        .route("/api/approve/{id}", post(approvals::post_approve))
        .route("/api/deny/{id}", post(approvals::post_deny))
        .route("/api/destroy/{name}", post(lifecycle_ops::post_destroy))
        .route("/api/kill/{name}", post(lifecycle_ops::post_kill))
        .route("/api/restart/{name}", post(lifecycle_ops::post_restart))
        .route("/api/start/{name}", post(lifecycle_ops::post_start))
        .route("/api/rebuild/{name}", post(lifecycle_ops::post_rebuild))
        .route("/api/update-all", post(lifecycle_ops::post_update_all))
        .route(
            "/api/infra-container/{name}/{action}",
            post(infra_containers::post_infra_container),
        )
        .route(
            "/api/answer-question/{id}",
            post(questions::post_answer_question),
        )
        .route(
            "/api/cancel-question/{id}",
            post(questions::post_cancel_question),
        )
        .route(
            "/api/purge-tombstone/{name}",
            post(tombstones::post_purge_tombstone),
        )
        .route(
            "/api/matrix-account-login",
            post(matrix_accounts::post_matrix_account_login),
        )
        .route(
            "/api/github-account",
            post(matrix_accounts::post_github_account).get(matrix_accounts::get_github_account),
        )
        .route(
            "/api/cancel-reminder/{id}",
            post(reminders::post_cancel_reminder),
        )
        .route(
            "/api/retry-reminder/{id}",
            post(reminders::post_retry_reminder),
        )
        .route("/api/request-spawn", post(misc_api::post_request_spawn))
        .route("/api/op-send", post(misc_api::post_op_send))
        .route("/api/meta-update", post(meta_inputs::post_meta_update))
        .route(
            "/api/dashboard/stream",
            get(state_snapshot::dashboard_stream),
        )
        .route(
            "/api/dashboard/history",
            get(state_snapshot::dashboard_history),
        )
        // No static fallback — the gateway owns the dist; unmatched paths 404.
        .with_state(AppState {
            coord,
            webhook_secret,
        });
    // Binds loopback-only; external access via gateway.
    // Rationale: docs/gateway.md::Firewall posture.
    let addr = SocketAddr::from(([127, 0, 0, 1], port));
    let listener = bind_with_retry(addr).await?;
    tracing::info!(%addr, "dashboard listening");
    axum::serve(listener, app).await?;
    Ok(())
}

// SPA shape + SSE channels: docs/web-ui/shape.md.

/// `SO_REUSEADDR` bind with retry. Retry mechanics, attempt-cap
/// rationale, and log-level cadence: `docs/web-ui/shape.md::Listener bind`.
async fn bind_with_retry(addr: SocketAddr) -> Result<tokio::net::TcpListener> {
    let mut delay_ms = 250u64;
    let mut attempts = 0u32;
    loop {
        match try_bind(addr) {
            Ok(l) => {
                if attempts > 0 {
                    tracing::info!(
                        %addr, attempts,
                        "dashboard: bind succeeded after retry"
                    );
                }
                return Ok(l);
            }
            Err(e) if e.kind() == std::io::ErrorKind::AddrInUse => {
                let attempt = attempts + 1;
                if attempt <= 12 {
                    tracing::warn!(
                        %addr, attempt,
                        "dashboard: AddrInUse, retrying in {delay_ms}ms"
                    );
                } else {
                    tracing::info!(
                        %addr, attempt,
                        "dashboard: AddrInUse still holding, retrying in {delay_ms}ms"
                    );
                }
                tokio::time::sleep(std::time::Duration::from_millis(delay_ms)).await;
                attempts += 1;
                delay_ms = (delay_ms * 2).min(2000);
            }
            Err(e) => {
                return Err(e).with_context(|| format!("bind dashboard on {addr}"));
            }
        }
    }
}

fn try_bind(addr: SocketAddr) -> std::io::Result<tokio::net::TcpListener> {
    let sock = match addr {
        SocketAddr::V4(_) => tokio::net::TcpSocket::new_v4()?,
        SocketAddr::V6(_) => tokio::net::TcpSocket::new_v6()?,
    };
    sock.set_reuseaddr(true)?;
    sock.bind(addr)?;
    sock.listen(1024)
}

/// Two-axis path-param guard for write routes. Combines:
///
/// 1. **format validation** ([`idents::AgentName::parse`]) — rejects
///    path traversal / unicode homoglyphs / empty + too-long names with
///    HTTP 400.
/// 2. **existence check** — looks up `name` in the coordinator's
///    container snapshot; unknown name → HTTP 404 with a clear
///    "no such agent" message. catches the operator-typo case where
///    a destructive POST would otherwise hit silently (mark-all-read
///    returning 0) or hit downstream lifecycle code that fails with
///    a confusing nspawn error.
///
/// Returns `None` when both checks pass (caller proceeds), `Some(Response)`
/// when the request should be rejected. Use at the top of every write
/// handler taking a name path-param. Read-only GET handlers and
/// handlers that legitimately operate on tombstoned agents (e.g.
/// `mark-all-read` on broker rows for a destroyed agent) call
/// [`idents::AgentName::parse`] directly and skip the existence check.
async fn guard_agent_name(state: &AppState, name: &str) -> Option<Response> {
    if let Err(reason) = idents::AgentName::parse(name) {
        return Some(
            (StatusCode::BAD_REQUEST, format!("bad agent name: {reason}")).into_response(),
        );
    }
    let snapshot = state.coord.containers_snapshot().await;
    if !snapshot.iter().any(|c| c.name == name) {
        return Some((StatusCode::NOT_FOUND, format!("no such agent: {name}")).into_response());
    }
    None
}

/// Convert either a logical name or a container name back to the logical
/// name. Sub-agents are `h-foo` → `foo`; manager stays `root`.
fn strip_container_prefix(name: &str) -> String {
    name.strip_prefix(lifecycle::AGENT_PREFIX)
        .unwrap_or(name)
        .to_owned()
}

/// The common internal-error case as a `ProblemDetails`: a 500 RFC 9457
/// (`application/problem+json`) value via the `problem_details` crate.
/// `from_status_code` sets `status` + `title` (the canonical reason phrase)
/// and leaves `type` as the default `about:blank`; `with_detail` carries the
/// caller message; the crate's axum `IntoResponse` emits the
/// `application/problem+json` body the frontend parses (it reads `detail`).
/// Handlers that surface client failures return `Result<_, ProblemDetails>`
/// and hand this (or an inline `from_status_code(4xx)`) straight to `Err` —
/// no manual `.into_response()`.
fn error_problem(message: &str) -> problem_details::ProblemDetails {
    problem_details::ProblemDetails::from_status_code(StatusCode::INTERNAL_SERVER_ERROR)
        .with_detail(message)
}

/// `Response` wrapper around [`error_problem`] for the many handlers typed
/// `-> Response` whose only failure mode is a 500 — they funnel errors
/// through here rather than threading a `Result` return type.
fn error_response(message: &str) -> Response {
    error_problem(message).into_response()
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn problem_details_carry_rfc9457_status_and_detail() {
        // Contract the frontend depends on: the problem_details crate
        // serialises the RFC 9457 members we rely on — `status` (numeric)
        // and `detail` (the caller message; the FE reads `.detail`).
        let pd = problem_details::ProblemDetails::from_status_code(StatusCode::BAD_REQUEST)
            .with_detail("bad input");
        let v = serde_json::to_value(&pd).expect("problem details serialise");
        assert_eq!(v["status"], 400);
        assert_eq!(v["detail"], "bad input");
        // The 500 wrapper path carries the internal-error status.
        let five =
            problem_details::ProblemDetails::from_status_code(StatusCode::INTERNAL_SERVER_ERROR)
                .with_detail("boom");
        let fv = serde_json::to_value(&five).expect("problem details serialise");
        assert_eq!(fv["status"], 500);
    }
}