talahon-http 3.0.0

//! Configuration for the CoPilot HTTP channel.
//!
//! Non-secret settings are read with [`EnvFile::get`] (process env wins over
//! `.env`); the API key is a secret and is only ever read from the `.env`
//! file ([`EnvFile::file_value`]).
//!
//! | Variable | Default | Meaning |
//! |---|---|---|
//! | `HTTP_API_KEY` (`.env` only) | unset | Shared secret; unset => every request but `/health` is rejected |
//! | `COPILOT_HTTP_PORT` | `3100` | Listen port |
//! | `COPILOT_HTTP_BIND` | `127.0.0.1` | Listen address. Loopback by default; set a private interface explicitly to expose the API |
//! | `COPILOT_HTTP_TLS_TERMINATED` | `false` | Operator asserts a TLS-terminating proxy fronts the API (silences the wildcard-bind warning) |
//! | `COPILOT_HTTP_MAX_CONNECTIONS` | `512` | Open connections across all peers |
//! | `COPILOT_HTTP_MAX_CONNECTIONS_PER_IP` | `320` | Open connections per peer IP (CoPilot usually connects from one address, so keep it above `COPILOT_HTTP_MAX_STREAMS`) |
//! | `COPILOT_HTTP_HEADER_TIMEOUT_SECS` | `15` | Time a client has to send complete request headers |
//! | `COPILOT_JID` | `http:copilot` | Base lane JID |
//! | `COPILOT_GROUP_FOLDER` | `copilot` | Group folder the lanes run in |
//! | `COPILOT_HTTP_CORS_ORIGINS` | empty | Comma-separated allowed browser origins (`*` allowed explicitly) |
//! | `COPILOT_HTTP_MAX_BODY_BYTES` | `262144` | Request body limit |
//! | `SESSION_IDLE_HOURS` | `24` | Idle time before a per-user lane is swept |
//! | `COPILOT_INVESTIGATION_DEDUP_MINUTES` | `10` | Repeat-trigger window (`0` disables) |
//! | `COPILOT_HTTP_AUTH_MAX_FAILURES` | `10` | Failed auths per IP before throttling |
//! | `COPILOT_HTTP_AUTH_WINDOW_SECS` | `300` | Throttle window |
//! | `COPILOT_PALACE_TIMEOUT_MS` | `30000` | Palace call timeout |
//! | `TALAHON_PALACE_HOST_EXEC` | unset | `unsafe` runs `mempalace/palace-call.sh` **on the host** when no palace runner is supplied. DANGEROUS: agents can write `mempalace-data/`, so this allows host code execution (MYTH-01) |
//! | `COPILOT_HTTP_MAX_USER_LANES` | `256` | Cap on in-memory per-user lanes |
//! | `COPILOT_HTTP_MAX_STREAMS` | `256` | Cap on concurrently open SSE streams |
//! | `COPILOT_EVALS_LEGACY_GROUP_DIR` | `false` | Migration only: `GET /evals` also reads the old `groups/<folder>/evals/`, which every CoPilot lane can write (forgeable records, N-2) |
//!
//! Eval records are served from the investigation lane's private state
//! directory, `<data_dir>/sessions/copilot-investigate/evals/` (the
//! container's `/home/agent/.talon/evals/`), which no other lane can reach.
//!
//! `/palace/*` is disabled (503) unless the host supplies a palace runner
//! (see [`crate::HttpDeps::with_palace`]) or the operator opts into host
//! execution with `TALAHON_PALACE_HOST_EXEC=unsafe`.

use std::fmt;
use std::net::{IpAddr, Ipv4Addr};
use std::path::{Path, PathBuf};
use std::time::Duration;

use chrono_tz::Tz;
use talon_core::config::TalonConfig;
use talon_core::env::EnvFile;
use talon_core::paths::is_valid_group_folder;
use talon_core::{Error, Result};

use crate::files::EVALS_DIR;
use crate::lanes::INVESTIGATE_SESSION_KEY;
use crate::palace::{HOST_EXEC_ENV, HOST_EXEC_UNSAFE};

/// Default listen port (used when `COPILOT_HTTP_PORT` is unset).
pub const DEFAULT_PORT: u16 = 3100;
/// Default base lane JID.
pub const DEFAULT_BASE_JID: &str = "http:copilot";
/// Default group folder for every CoPilot lane.
pub const DEFAULT_GROUP_FOLDER: &str = "copilot";
/// Default request body limit (256 KiB).
pub const DEFAULT_MAX_BODY_BYTES: usize = 256 * 1024;
/// Upper bound accepted for `COPILOT_HTTP_MAX_BODY_BYTES`.
pub const MAX_BODY_BYTES_CEILING: usize = 16 * 1024 * 1024;
/// Keys shorter than this trigger a startup warning.
pub const MIN_RECOMMENDED_KEY_LEN: usize = 16;
/// Default listen address: loopback only (MYTH-05).
pub const DEFAULT_BIND: IpAddr = IpAddr::V4(Ipv4Addr::LOCALHOST);
/// Default cap on open connections.
pub const DEFAULT_MAX_CONNECTIONS: usize = 512;
/// Default cap on open connections from one peer IP.
pub const DEFAULT_MAX_CONNECTIONS_PER_IP: usize = 320;
/// Default time a client has to send complete request headers.
pub const DEFAULT_HEADER_READ_TIMEOUT: Duration = Duration::from_secs(15);
/// Env flag: also serve eval records from the legacy, shared
/// `groups/<folder>/evals/` directory (migration only; forgeable).
pub const EVALS_LEGACY_GROUP_DIR_ENV: &str = "COPILOT_EVALS_LEGACY_GROUP_DIR";

/// The shared API key. `Debug` never prints the value.
#[derive(Clone, Default, PartialEq, Eq)]
pub struct ApiKey(String);

impl ApiKey {
    /// Wrap a key value.
    pub fn new(value: impl Into<String>) -> Self {
        Self(value.into())
    }

    /// An unset key (every authenticated request is rejected).
    pub fn unset() -> Self {
        Self(String::new())
    }

    /// Whether a non-blank key is configured.
    pub fn is_configured(&self) -> bool {
        !self.0.trim().is_empty()
    }

    /// The raw key, for the constant-time comparison only. Never log it.
    pub fn expose(&self) -> &str {
        &self.0
    }

    /// Length of the configured key in bytes.
    pub fn len(&self) -> usize {
        self.0.len()
    }

    /// Whether the key is empty.
    pub fn is_empty(&self) -> bool {
        self.0.is_empty()
    }
}

impl fmt::Debug for ApiKey {
    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
        if self.is_configured() {
            f.write_str("ApiKey(<redacted>)")
        } else {
            f.write_str("ApiKey(<unset>)")
        }
    }
}

/// Resolved configuration for the HTTP channel.
#[derive(Debug, Clone)]
pub struct HttpConfig {
    /// Listen address (default `127.0.0.1`).
    pub bind: IpAddr,
    /// A TLS-terminating proxy fronts the API (operator assertion; only
    /// silences the wildcard-bind warning).
    pub tls_terminated: bool,
    /// Max simultaneously open connections.
    pub max_connections: usize,
    /// Max simultaneously open connections from one peer IP.
    pub max_connections_per_ip: usize,
    /// Time a client has to send complete request headers. Established
    /// requests (SSE streams) have no idle timeout.
    pub header_read_timeout: Duration,
    /// Listen port (`0` picks a free port; see `HttpChannel::local_addr`).
    pub port: u16,
    /// Shared secret callers present via `X-Api-Key` or `Authorization: Bearer`.
    pub api_key: ApiKey,
    /// Base lane JID (`http:copilot`).
    pub base_jid: String,
    /// Group folder every lane runs in.
    pub group_folder: String,
    /// Project root (`mempalace/`, `siem/`, ... live below it).
    pub project_root: PathBuf,
    /// `<project_root>/groups`.
    pub groups_dir: PathBuf,
    /// Host runtime data (`<project_root>/data`): lane state directories
    /// live in `<data_dir>/sessions/<session_key>`.
    pub data_dir: PathBuf,
    /// `COPILOT_EVALS_LEGACY_GROUP_DIR`: `GET /evals` additionally reads
    /// the pre-N-2 location `groups/<folder>/evals/` (writable by every
    /// CoPilot lane, so records found there are forgeable). Off by default.
    pub evals_legacy_group_dir: bool,
    /// Timezone used for `once` task timestamps and cron evaluation.
    pub timezone: Tz,
    /// Allowed CORS origins (exact match, or `*`). Empty => no CORS headers.
    pub cors_origins: Vec<String>,
    /// Request body limit in bytes.
    pub max_body_bytes: usize,
    /// Idle time after which a per-user lane is swept.
    pub lane_idle: Duration,
    /// How often the idle-lane sweep runs.
    pub lane_sweep_interval: Duration,
    /// Interval between SSE keepalive comments.
    pub sse_keepalive: Duration,
    /// Repeat triggers for the same alert inside this window return the
    /// existing job. Zero disables de-duplication.
    pub dedup_window: Duration,
    /// Failed authentications per IP (inside `auth_window`) before 429s.
    pub auth_max_failures: u32,
    /// Auth-failure throttle window.
    pub auth_window: Duration,
    /// Path of `mempalace/palace-call.sh` (only used with
    /// [`Self::palace_host_exec`]).
    pub palace_script: PathBuf,
    /// `TALAHON_PALACE_HOST_EXEC=unsafe`: without an explicitly supplied
    /// palace runner, run `palace_script` directly on the host. Dangerous
    /// (MYTH-01); off by default.
    pub palace_host_exec: bool,
    /// Timeout for one palace call.
    pub palace_timeout: Duration,
    /// Max bytes of stdout accepted from a palace call.
    pub palace_max_output_bytes: usize,
    /// Max concurrently running palace calls.
    pub palace_max_concurrency: usize,
    /// Cap on in-memory per-user lanes.
    pub max_user_lanes: usize,
    /// Cap on SSE requests queued on a single lane.
    pub max_pending_per_lane: usize,
    /// Cap on concurrently open SSE streams across all lanes.
    pub max_streams: usize,
    /// Seed the (paused) 15-minute alert digest task on connect.
    pub seed_digest_task: bool,
}

impl HttpConfig {
    /// Defaults rooted at `project_root` (API key unset). Intended for tests
    /// and programmatic construction; production uses [`Self::from_talon_config`].
    pub fn new(project_root: impl Into<PathBuf>) -> Self {
        let project_root = project_root.into();
        Self {
            bind: DEFAULT_BIND,
            tls_terminated: false,
            max_connections: DEFAULT_MAX_CONNECTIONS,
            max_connections_per_ip: DEFAULT_MAX_CONNECTIONS_PER_IP,
            header_read_timeout: DEFAULT_HEADER_READ_TIMEOUT,
            port: DEFAULT_PORT,
            api_key: ApiKey::unset(),
            base_jid: DEFAULT_BASE_JID.to_string(),
            group_folder: DEFAULT_GROUP_FOLDER.to_string(),
            groups_dir: project_root.join("groups"),
            data_dir: project_root.join("data"),
            evals_legacy_group_dir: false,
            palace_script: project_root.join("mempalace").join("palace-call.sh"),
            palace_host_exec: false,
            project_root,
            timezone: chrono_tz::UTC,
            cors_origins: Vec::new(),
            max_body_bytes: DEFAULT_MAX_BODY_BYTES,
            lane_idle: Duration::from_secs(24 * 3600),
            lane_sweep_interval: Duration::from_secs(15 * 60),
            sse_keepalive: Duration::from_secs(15),
            dedup_window: Duration::from_secs(10 * 60),
            auth_max_failures: 10,
            auth_window: Duration::from_secs(300),
            palace_timeout: Duration::from_secs(30),
            palace_max_output_bytes: 1024 * 1024,
            palace_max_concurrency: 4,
            max_user_lanes: 256,
            max_pending_per_lane: 8,
            max_streams: 256,
            seed_digest_task: true,
        }
    }

    /// Resolve from the host configuration.
    pub fn from_talon_config(cfg: &TalonConfig) -> Result<Self> {
        let mut http = Self::from_env(&cfg.project_root, &cfg.groups_dir, cfg.timezone, &cfg.env)?;
        http.data_dir = cfg.data_dir.clone();
        Ok(http)
    }

    /// Resolve from an [`EnvFile`] (see the module docs for the keys).
    pub fn from_env(
        project_root: &Path,
        groups_dir: &Path,
        timezone: Tz,
        env: &EnvFile,
    ) -> Result<Self> {
        let mut cfg = Self::new(project_root);
        cfg.groups_dir = groups_dir.to_path_buf();
        cfg.timezone = timezone;

        if let Some(port) = env.get("COPILOT_HTTP_PORT") {
            cfg.port = port.trim().parse::<u16>().map_err(|_| {
                Error::Config(format!("COPILOT_HTTP_PORT {port:?} is not a valid port"))
            })?;
        }
        if let Some(bind) = env.get("COPILOT_HTTP_BIND") {
            cfg.bind = bind.trim().parse::<IpAddr>().map_err(|_| {
                Error::Config(format!("COPILOT_HTTP_BIND {bind:?} is not an IP address"))
            })?;
        }
        if let Some(jid) = env.get("COPILOT_JID") {
            let jid = jid.trim().to_string();
            if !is_valid_base_jid(&jid) {
                return Err(Error::Config(format!(
                    "COPILOT_JID {jid:?} is not a valid JID"
                )));
            }
            cfg.base_jid = jid;
        }
        if let Some(folder) = env.get("COPILOT_GROUP_FOLDER") {
            let folder = folder.trim().to_string();
            if !is_valid_group_folder(&folder) {
                return Err(Error::Config(format!(
                    "COPILOT_GROUP_FOLDER {folder:?} is not a valid group folder"
                )));
            }
            cfg.group_folder = folder;
        }
        cfg.api_key = ApiKey::new(env.file_value("HTTP_API_KEY").unwrap_or_default().trim());
        if let Some(origins) = env.get("COPILOT_HTTP_CORS_ORIGINS") {
            cfg.cors_origins = parse_cors_origins(&origins)?;
        }
        cfg.max_body_bytes = (env.get_u64(
            "COPILOT_HTTP_MAX_BODY_BYTES",
            DEFAULT_MAX_BODY_BYTES as u64,
            1024,
        ) as usize)
            .min(MAX_BODY_BYTES_CEILING);
        cfg.lane_idle = Duration::from_secs(env.get_u64("SESSION_IDLE_HOURS", 24, 1) * 3600);
        cfg.dedup_window =
            Duration::from_secs(env.get_u64("COPILOT_INVESTIGATION_DEDUP_MINUTES", 10, 0) * 60);
        cfg.auth_max_failures =
            u32::try_from(env.get_u64("COPILOT_HTTP_AUTH_MAX_FAILURES", 10, 1)).unwrap_or(u32::MAX);
        cfg.auth_window = Duration::from_secs(env.get_u64("COPILOT_HTTP_AUTH_WINDOW_SECS", 300, 1));
        cfg.palace_timeout =
            Duration::from_millis(env.get_u64("COPILOT_PALACE_TIMEOUT_MS", 30_000, 1_000));
        cfg.max_user_lanes = env.get_u64("COPILOT_HTTP_MAX_USER_LANES", 256, 1) as usize;
        cfg.max_streams = env.get_u64("COPILOT_HTTP_MAX_STREAMS", 256, 1) as usize;
        cfg.tls_terminated = env.get_bool("COPILOT_HTTP_TLS_TERMINATED");
        cfg.max_connections = env.get_u64(
            "COPILOT_HTTP_MAX_CONNECTIONS",
            DEFAULT_MAX_CONNECTIONS as u64,
            1,
        ) as usize;
        cfg.max_connections_per_ip = env.get_u64(
            "COPILOT_HTTP_MAX_CONNECTIONS_PER_IP",
            DEFAULT_MAX_CONNECTIONS_PER_IP as u64,
            1,
        ) as usize;
        cfg.header_read_timeout = Duration::from_secs(env.get_u64(
            "COPILOT_HTTP_HEADER_TIMEOUT_SECS",
            DEFAULT_HEADER_READ_TIMEOUT.as_secs(),
            1,
        ));
        cfg.palace_host_exec = parse_host_exec(env.get(HOST_EXEC_ENV).as_deref())?;
        cfg.evals_legacy_group_dir = env.get_bool(EVALS_LEGACY_GROUP_DIR_ENV);
        Ok(cfg)
    }

    /// Startup warning for a listen address that exposes the API (and its
    /// cleartext API key) on every interface without TLS in front.
    pub fn exposure_warning(&self) -> Option<String> {
        (self.bind.is_unspecified() && !self.tls_terminated).then(|| {
            format!(
                "COPILOT_HTTP_BIND={} exposes the CoPilot HTTP API on every interface without TLS: \
                 the API key travels in cleartext. Bind a private interface (or 127.0.0.1) and/or \
                 put a TLS-terminating proxy in front (then set COPILOT_HTTP_TLS_TERMINATED=true)",
                self.bind
            )
        })
    }

    /// `<groups_dir>/<group_folder>`.
    pub fn group_dir(&self) -> PathBuf {
        self.groups_dir.join(&self.group_folder)
    }

    /// `<groups_dir>/<group_folder>/prompts`.
    pub fn prompts_dir(&self) -> PathBuf {
        self.group_dir().join("prompts")
    }

    /// `<data_dir>/sessions`: the (operator-controlled) root of every
    /// lane's private state directory.
    pub fn sessions_dir(&self) -> PathBuf {
        self.data_dir.join("sessions")
    }

    /// Session key of the investigation lane, whose state directory holds
    /// the eval records (the key [`crate::HttpState::register_base_lanes`]
    /// registers that lane with).
    pub fn investigation_session_key(&self) -> &'static str {
        INVESTIGATE_SESSION_KEY
    }

    /// `<data_dir>/sessions/<investigation session key>/evals` — where the
    /// investigation agent writes eval records (`/home/agent/.talon/evals`
    /// inside its container) and where `GET /evals` reads them. Reads never
    /// go through this path directly: the lane directory and `evals/` are
    /// opened without following symlinks.
    pub fn evals_dir(&self) -> PathBuf {
        self.sessions_dir()
            .join(self.investigation_session_key())
            .join(EVALS_DIR)
    }

    /// `<groups_dir>/<group_folder>/evals` — the pre-N-2 location, shared by
    /// every CoPilot lane; read only with [`Self::evals_legacy_group_dir`].
    pub fn legacy_evals_dir(&self) -> PathBuf {
        self.group_dir().join(EVALS_DIR)
    }
}

/// `TALAHON_PALACE_HOST_EXEC`: only the exact value `unsafe` enables host
/// execution; common "off" spellings disable it; anything else is a
/// configuration error rather than a silent guess.
fn parse_host_exec(raw: Option<&str>) -> Result<bool> {
    let Some(value) = raw.map(str::trim) else {
        return Ok(false);
    };
    if value == HOST_EXEC_UNSAFE {
        return Ok(true);
    }
    if value.is_empty()
        || ["0", "false", "no", "off"]
            .iter()
            .any(|off| off.eq_ignore_ascii_case(value))
    {
        return Ok(false);
    }
    Err(Error::Config(format!(
        "{HOST_EXEC_ENV}={value:?} is not recognised: set it to '{HOST_EXEC_UNSAFE}' to run \
         mempalace/palace-call.sh on the host (DANGEROUS: agent-writable palace data allows host \
         code execution) or leave it unset"
    )))
}

/// A base JID: 1-128 printable ASCII characters without whitespace, not
/// ending in `:` (sub-lanes are formed by appending `:<suffix>`).
fn is_valid_base_jid(jid: &str) -> bool {
    !jid.is_empty()
        && jid.len() <= 128
        && !jid.ends_with(':')
        && jid.bytes().all(|b| b.is_ascii_graphic())
}

/// Parse `COPILOT_HTTP_CORS_ORIGINS`: comma-separated `http(s)://host[:port]`
/// origins or `*`. Trailing slashes are dropped.
pub fn parse_cors_origins(raw: &str) -> Result<Vec<String>> {
    let mut out = Vec::new();
    for item in raw.split(',') {
        let item = item.trim().trim_end_matches('/');
        if item.is_empty() {
            continue;
        }
        let host = item
            .strip_prefix("https://")
            .or_else(|| item.strip_prefix("http://"));
        let valid = item == "*"
            || matches!(host, Some(h) if !h.is_empty()
                && h.len() <= 253
                && h.bytes().all(|b| b.is_ascii_graphic() && b != b'/'));
        if !valid {
            return Err(Error::Config(format!(
                "COPILOT_HTTP_CORS_ORIGINS entry {item:?} is not an origin (scheme://host[:port]) or '*'"
            )));
        }
        out.push(item.to_string());
    }
    Ok(out)
}

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

    fn env(content: &str) -> EnvFile {
        EnvFile::from_str_content(content)
    }

    #[test]
    fn defaults_match_the_ts_release() {
        let cfg = HttpConfig::new("/opt/talahon");
        assert_eq!(cfg.port, 3100);
        assert_eq!(cfg.base_jid, "http:copilot");
        assert_eq!(cfg.group_folder, "copilot");
        assert_eq!(
            cfg.prompts_dir(),
            PathBuf::from("/opt/talahon/groups/copilot/prompts")
        );
        assert_eq!(cfg.data_dir, PathBuf::from("/opt/talahon/data"));
        assert_eq!(
            cfg.evals_dir(),
            PathBuf::from("/opt/talahon/data/sessions/copilot-investigate/evals")
        );
        assert_eq!(
            cfg.legacy_evals_dir(),
            PathBuf::from("/opt/talahon/groups/copilot/evals")
        );
        assert!(!cfg.evals_legacy_group_dir);
        assert_eq!(
            cfg.palace_script,
            PathBuf::from("/opt/talahon/mempalace/palace-call.sh")
        );
        assert!(!cfg.api_key.is_configured());
        assert_eq!(cfg.dedup_window, Duration::from_secs(600));
        assert_eq!(cfg.sse_keepalive, Duration::from_secs(15));
        assert!(!cfg.palace_host_exec);
    }

    #[test]
    fn default_bind_is_loopback() {
        let cfg = HttpConfig::new("/opt/talahon");
        assert_eq!(cfg.bind, IpAddr::V4(Ipv4Addr::LOCALHOST));
        assert!(cfg.exposure_warning().is_none());
        if std::env::var("COPILOT_HTTP_BIND").is_err() {
            let cfg = HttpConfig::from_env(
                Path::new("/x"),
                Path::new("/x/g"),
                chrono_tz::UTC,
                &env("COPILOT_HTTP_PORT=3100\n"),
            )
            .unwrap();
            assert_eq!(cfg.bind.to_string(), "127.0.0.1");
        }
    }

    #[test]
    fn wildcard_bind_without_tls_warns() {
        let mut cfg = HttpConfig::new("/opt/talahon");
        for addr in ["0.0.0.0", "::"] {
            cfg.bind = addr.parse().unwrap();
            cfg.tls_terminated = false;
            let w = cfg.exposure_warning().unwrap();
            assert!(w.contains("every interface"), "{w}");
            cfg.tls_terminated = true;
            assert!(cfg.exposure_warning().is_none());
        }
        // An explicitly chosen private interface does not warn.
        cfg.tls_terminated = false;
        cfg.bind = "10.0.0.5".parse().unwrap();
        assert!(cfg.exposure_warning().is_none());
        if std::env::var("COPILOT_HTTP_BIND").is_err()
            && std::env::var("COPILOT_HTTP_TLS_TERMINATED").is_err()
        {
            let cfg = HttpConfig::from_env(
                Path::new("/x"),
                Path::new("/x/g"),
                chrono_tz::UTC,
                &env("COPILOT_HTTP_BIND=0.0.0.0\nCOPILOT_HTTP_TLS_TERMINATED=true\n"),
            )
            .unwrap();
            assert!(cfg.bind.is_unspecified());
            assert!(cfg.tls_terminated);
            assert!(cfg.exposure_warning().is_none());
        }
    }

    #[test]
    fn connection_limits_are_configurable() {
        let cfg = HttpConfig::new("/opt/talahon");
        assert_eq!(cfg.max_connections, DEFAULT_MAX_CONNECTIONS);
        assert!(cfg.max_connections_per_ip > cfg.max_streams);
        assert_eq!(cfg.header_read_timeout, Duration::from_secs(15));
        if [
            "COPILOT_HTTP_MAX_CONNECTIONS",
            "COPILOT_HTTP_MAX_CONNECTIONS_PER_IP",
            "COPILOT_HTTP_HEADER_TIMEOUT_SECS",
        ]
        .iter()
        .any(|k| std::env::var(k).is_ok())
        {
            return;
        }
        let cfg = HttpConfig::from_env(
            Path::new("/x"),
            Path::new("/x/g"),
            chrono_tz::UTC,
            &env("COPILOT_HTTP_MAX_CONNECTIONS=64\nCOPILOT_HTTP_MAX_CONNECTIONS_PER_IP=0\nCOPILOT_HTTP_HEADER_TIMEOUT_SECS=5\n"),
        )
        .unwrap();
        assert_eq!(cfg.max_connections, 64);
        assert_eq!(cfg.max_connections_per_ip, 1);
        assert_eq!(cfg.header_read_timeout, Duration::from_secs(5));
    }

    #[test]
    fn palace_host_exec_requires_the_exact_unsafe_value() {
        assert!(!parse_host_exec(None).unwrap());
        for off in ["", "0", "false", "NO", "off"] {
            assert!(!parse_host_exec(Some(off)).unwrap(), "{off}");
        }
        assert!(parse_host_exec(Some("unsafe")).unwrap());
        assert!(parse_host_exec(Some(" unsafe ")).unwrap());
        for bad in ["1", "true", "yes", "UNSAFE", "on"] {
            let err = parse_host_exec(Some(bad)).unwrap_err().to_string();
            assert!(err.contains("DANGEROUS"), "{bad}: {err}");
        }
        if !talon_core::env::process_var_is_set(HOST_EXEC_ENV) {
            let from = |content: &str| {
                HttpConfig::from_env(
                    Path::new("/x"),
                    Path::new("/x/g"),
                    chrono_tz::UTC,
                    &env(content),
                )
            };
            assert!(!from("").unwrap().palace_host_exec);
            assert!(
                from("TALAHON_PALACE_HOST_EXEC=unsafe\n")
                    .unwrap()
                    .palace_host_exec
            );
            assert!(from("TALAHON_PALACE_HOST_EXEC=true\n").is_err());
        }
    }

    #[test]
    fn legacy_evals_dir_is_opt_in() {
        if std::env::var(EVALS_LEGACY_GROUP_DIR_ENV).is_ok() {
            return;
        }
        let from = |content: &str| {
            HttpConfig::from_env(
                Path::new("/x"),
                Path::new("/x/g"),
                chrono_tz::UTC,
                &env(content),
            )
            .unwrap()
        };
        assert!(!from("").evals_legacy_group_dir);
        assert!(!from("COPILOT_EVALS_LEGACY_GROUP_DIR=false\n").evals_legacy_group_dir);
        assert!(from("COPILOT_EVALS_LEGACY_GROUP_DIR=true\n").evals_legacy_group_dir);
    }

    #[test]
    fn data_dir_comes_from_the_host_config() {
        let mut talon = TalonConfig::from_env(Path::new("/srv/talahon"), env(""));
        talon.data_dir = PathBuf::from("/var/lib/talon-data");
        let Ok(cfg) = HttpConfig::from_talon_config(&talon) else {
            // A conflicting process env (e.g. COPILOT_HTTP_PORT) is not
            // what this test is about.
            return;
        };
        assert_eq!(
            cfg.evals_dir(),
            PathBuf::from("/var/lib/talon-data/sessions/copilot-investigate/evals")
        );
        assert_eq!(cfg.investigation_session_key(), INVESTIGATE_SESSION_KEY);
    }

    #[test]
    fn api_key_comes_from_the_env_file_and_is_never_debug_printed() {
        let cfg = HttpConfig::from_env(
            Path::new("/x"),
            Path::new("/x/groups"),
            chrono_tz::UTC,
            &env("HTTP_API_KEY=super-secret-value-123\n"),
        )
        .unwrap();
        assert!(cfg.api_key.is_configured());
        assert_eq!(cfg.api_key.expose(), "super-secret-value-123");
        let dbg = format!("{cfg:?}");
        assert!(!dbg.contains("super-secret"), "{dbg}");
        assert!(dbg.contains("<redacted>"));
    }

    #[test]
    fn blank_key_is_unset() {
        let k = ApiKey::new("   ");
        assert!(!k.is_configured());
        assert_eq!(format!("{k:?}"), "ApiKey(<unset>)");
    }

    #[test]
    fn invalid_settings_are_rejected() {
        let bad = |content: &str| {
            HttpConfig::from_env(
                Path::new("/x"),
                Path::new("/x/g"),
                chrono_tz::UTC,
                &env(content),
            )
        };
        if std::env::var("COPILOT_GROUP_FOLDER").is_err() {
            assert!(bad("COPILOT_GROUP_FOLDER=../etc\n").is_err());
        }
        if std::env::var("COPILOT_HTTP_PORT").is_err() {
            assert!(bad("COPILOT_HTTP_PORT=99999\n").is_err());
        }
        if std::env::var("COPILOT_HTTP_BIND").is_err() {
            assert!(bad("COPILOT_HTTP_BIND=not-an-ip\n").is_err());
        }
        if std::env::var("COPILOT_HTTP_CORS_ORIGINS").is_err() {
            assert!(bad("COPILOT_HTTP_CORS_ORIGINS=javascript:alert(1)\n").is_err());
        }
    }

    #[test]
    fn numeric_settings_apply_with_bounds() {
        if std::env::var("COPILOT_INVESTIGATION_DEDUP_MINUTES").is_ok()
            || std::env::var("COPILOT_HTTP_MAX_BODY_BYTES").is_ok()
        {
            return;
        }
        let cfg = HttpConfig::from_env(
            Path::new("/x"),
            Path::new("/x/g"),
            chrono_tz::UTC,
            &env(
                "COPILOT_INVESTIGATION_DEDUP_MINUTES=0\nCOPILOT_HTTP_MAX_BODY_BYTES=999999999999\n",
            ),
        )
        .unwrap();
        assert_eq!(cfg.dedup_window, Duration::ZERO);
        assert_eq!(cfg.max_body_bytes, MAX_BODY_BYTES_CEILING);
    }

    #[test]
    fn cors_origins_parse() {
        assert_eq!(
            parse_cors_origins(" https://copilot.example.com/ , http://10.0.0.5:5173,*").unwrap(),
            vec![
                "https://copilot.example.com".to_string(),
                "http://10.0.0.5:5173".to_string(),
                "*".to_string()
            ]
        );
        assert!(parse_cors_origins("https://a.example/path").is_err());
        assert!(parse_cors_origins("ftp://a").is_err());
        assert!(parse_cors_origins("").unwrap().is_empty());
    }

    #[test]
    fn base_jid_validation() {
        assert!(is_valid_base_jid("http:copilot"));
        assert!(!is_valid_base_jid("http:copilot:"));
        assert!(!is_valid_base_jid("has space"));
        assert!(!is_valid_base_jid(""));
    }
}