//! Per-agent notification pollers — shared library half.
//!
//! Two binaries ship from this crate, one per notification host:
//!
//! - **`hive-forge-notify`** — the hive's internal Forgejo. Always
//!   deployed; the behaviour predates this split and is unchanged.
//! - **`hive-github-notify`** — github.com, for agents that have a PAT.
//!
//! They are separate *binaries* rather than one process with two loops so
//! the deployment can choose: an agent module installs the GitHub unit or
//! it doesn't, and the decision lives in the module rather than in a cargo
//! feature. A feature flag would unify across the workspace — enabling it
//! for one consumer changes feature resolution for the whole graph and
//! stops the two builds sharing any cached crate — which is a permanent
//! cost for something a second binary expresses for free.
//!
//! Everything except the host-specific calls (list unread, mark read,
//! resolve own login) is shared and lives here: classification, wake
//! formatting, the tolerant parse, delivery dedupe, and the todo upsert.
//! The host differences live behind [`source::Source`].

pub mod notify;
pub mod source;

/// Re-exported so a binary can spell it once at the crate root alongside
/// the other things it needs to build a client; it is a property of the
/// poller, not of the notification format.
pub use notify::HTTP_TIMEOUT_SECS;

/// Retry policy for the harness's in-agent socket. Deliberately fail-fast:
/// both callers are inside the poll loop and both treat a failed request as
/// "leave the thread unread and try again next tick", so the poll interval
/// *is* the retry — a second, in-request backoff would only stack sleeps on
/// top of it and delay the rest of the batch. That is the opposite
/// trade-off from the serve loop's client, which rides out a hive-c0re
/// restart because its callers have no natural retry of their own.
pub const TODO_SOCKET_RETRY: hive_sock_client::Retry = hive_sock_client::Retry::None;

/// Resolve the harness's in-agent todo socket from the environment, falling
/// back to the well-known path. Shared by both binaries so they can't drift
/// on where they deliver.
#[must_use]
pub fn agent_socket() -> std::path::PathBuf {
    std::env::var_os("HIVE_AGENT_SOCKET").map_or_else(
        || std::path::PathBuf::from(hive_agent_sock::DEFAULT_AGENT_SOCKET),
        std::path::PathBuf::from,
    )
}

/// Install the tracing subscriber both binaries use: `RUST_LOG` when set,
/// `info` otherwise.
pub fn init_tracing() {
    tracing_subscriber::fmt()
        .with_env_filter(
            tracing_subscriber::EnvFilter::try_from_env("RUST_LOG")
                .unwrap_or_else(|_| tracing_subscriber::EnvFilter::new("info")),
        )
        // This is a systemd-managed daemon — stdout always goes to journald,
        // never a human terminal, and journald doesn't strip ANSI escapes:
        // they land in victorialogs as raw byte-array spam otherwise.
        .with_ansi(false)
        .init();
}

/// Read `HYPERHIVE_STATE_DIR`, the directory holding the agent's
/// credentials (`forge-token`, `github-token`). Empty when unset, which
/// makes the token paths relative and the read fail — the callers treat
/// that as "not configured" and settle.
#[must_use]
pub fn state_dir() -> String {
    std::env::var("HYPERHIVE_STATE_DIR").unwrap_or_default()
}

/// Where this agent's forge token is read from, first match wins:
/// `HIVE_FORGE_TOKEN_FILE` (the copy the agent fetched from the swarm secret
/// store, set by `nix/agent-modules/forge-token.nix`), then
/// `<state_dir>/forge-token` (the file the hive used to write, still the only
/// copy on an agent without a store identity).
#[must_use]
pub fn forge_token_paths(state_dir: &str) -> Vec<std::path::PathBuf> {
    let mut paths = Vec::with_capacity(2);
    if let Ok(fetched) = std::env::var("HIVE_FORGE_TOKEN_FILE")
        && !fetched.is_empty()
    {
        paths.push(std::path::PathBuf::from(fetched));
    }
    paths.push(std::path::Path::new(state_dir).join("forge-token"));
    paths
}

/// The first non-empty token among `paths`, trimmed. `None` when none of
/// them holds one.
#[must_use]
pub fn read_first_token(paths: &[std::path::PathBuf]) -> Option<String> {
    paths.iter().find_map(|p| {
        let t = std::fs::read_to_string(p).ok()?;
        let t = t.trim();
        (!t.is_empty()).then(|| t.to_owned())
    })
}

#[cfg(test)]
mod token_tests {
    use super::read_first_token;

    fn scratch(tag: &str) -> std::path::PathBuf {
        let ts = std::time::SystemTime::now()
            .duration_since(std::time::UNIX_EPOCH)
            .map_or(0, |d| d.as_nanos());
        let dir = std::env::temp_dir().join(format!("hive-forge-notify-token-{tag}-{ts}"));
        std::fs::create_dir_all(&dir).expect("create scratch dir");
        dir
    }

    #[test]
    fn the_fetched_token_wins_over_the_state_file() {
        let dir = scratch("wins");
        let (fetched, state) = (dir.join("fetched"), dir.join("forge-token"));
        std::fs::write(&fetched, "new\n").expect("write");
        std::fs::write(&state, "old\n").expect("write");
        assert_eq!(read_first_token(&[fetched, state]).as_deref(), Some("new"));
        let _ = std::fs::remove_dir_all(&dir);
    }

    #[test]
    fn a_missing_or_empty_fetched_token_falls_back_to_the_state_file() {
        let dir = scratch("fallback");
        let (fetched, state) = (dir.join("fetched"), dir.join("forge-token"));
        std::fs::write(&state, "old\n").expect("write");
        assert_eq!(
            read_first_token(&[fetched.clone(), state.clone()]).as_deref(),
            Some("old")
        );
        std::fs::write(&fetched, "\n").expect("write");
        assert_eq!(read_first_token(&[fetched, state]).as_deref(), Some("old"));
        let _ = std::fs::remove_dir_all(&dir);
    }

    #[test]
    fn no_token_anywhere_is_none() {
        let dir = scratch("none");
        assert_eq!(read_first_token(&[dir.join("a"), dir.join("b")]), None);
        let _ = std::fs::remove_dir_all(&dir);
    }
}