//! Boot-time `claude plugin install` driver. Reads the list declared
//! via the `services.hyperhive.agent.claudePlugins` NixOS option (rendered to
//! `/etc/hyperhive/claude-plugins.json` by the harness module) and
//! shells out `claude plugin install <spec>` for each entry. Runs once
//! per harness boot before the turn loop; `claude plugin install`
//! is expected to be idempotent so reinstalling on each container
//! recreate is fine. Failures log a warning but do not abort boot —
//! we'd rather start without a plugin than refuse to serve.
//!
//! Before installing, all configured marketplaces are updated so that
//! plugin specs resolve against current index data. Marketplace update
//! failures are non-fatal — stale index is better than no install attempt.

use std::io;
use std::process::Output;
use std::time::{Duration, Instant};

use tokio::process::Command;

const PLUGINS_PATH: &str = "/etc/hyperhive/claude-plugins.json";
const MARKETPLACES_PATH: &str = "/etc/hyperhive/claude-marketplaces.json";
const AUTO_UPDATE_PATH: &str = "/etc/hyperhive/claude-plugins-auto-update.json";

/// Per-call deadline for `claude plugin …`; a git clone over a slow link fits, a hung fetch does not.
const PLUGIN_CALL_TIMEOUT: Duration = Duration::from_mins(2);

/// Total budget for the whole serial sequence in [`install_configured`]. The
/// harness awaits it before serving the web UI, so this is the longest a
/// blackholed fetch path can delay boot, however many marketplaces and plugins
/// are configured.
const PLUGIN_BOOT_BUDGET: Duration = Duration::from_mins(4);

/// The deadline for the next call: [`PLUGIN_CALL_TIMEOUT`], cut to what is
/// left of the boot budget ending at `boot_end` (zero once it is spent).
fn call_budget(now: Instant, boot_end: Instant) -> Duration {
    PLUGIN_CALL_TIMEOUT.min(boot_end.saturating_duration_since(now))
}

/// Run `claude plugin <args>` under [`call_budget`]. On timeout the child is
/// killed (`kill_on_drop`) and a `TimedOut` error is returned. Only the
/// `claude` process is killed; a `git` it forked is not.
async fn run_claude_plugin(args: &[&str], boot_end: Instant) -> io::Result<Output> {
    let mut cmd = Command::new("claude");
    cmd.arg("plugin").args(args);
    run_bounded(cmd, call_budget(Instant::now(), boot_end)).await
}

/// Run `cmd` to completion within `deadline`; the child is killed when the
/// deadline passes.
async fn run_bounded(mut cmd: Command, deadline: Duration) -> io::Result<Output> {
    let call = cmd.kill_on_drop(true).output();
    tokio::time::timeout(deadline, call)
        .await
        .unwrap_or_else(|_| {
            Err(io::Error::new(
                io::ErrorKind::TimedOut,
                format!("no exit within {}s", deadline.as_secs_f32()),
            ))
        })
}

/// Add every marketplace from `/etc/hyperhive/claude-marketplaces.json`
/// via `claude plugin marketplace add <source>`. Idempotent: re-add of
/// an existing marketplace is treated as success (claude prints an
/// "already exists" message and exits non-zero on some versions).
/// Required before any `<plugin>@<marketplace>` install can resolve.
async fn add_marketplaces(boot_end: Instant) {
    let Ok(raw) = tokio::fs::read_to_string(MARKETPLACES_PATH).await else {
        return;
    };
    let sources: Vec<String> = match serde_json::from_str(&raw) {
        Ok(v) => v,
        Err(e) => {
            tracing::warn!(path = MARKETPLACES_PATH, error = ?e, "claude-marketplaces spec parse failed; skipping");
            return;
        }
    };
    for source in sources {
        match run_claude_plugin(&["marketplace", "add", &source], boot_end).await {
            Ok(out) if out.status.success() => {
                tracing::info!(source = %source, "claude plugin marketplace add ok");
            }
            Ok(out) => {
                let stderr = String::from_utf8_lossy(&out.stderr);
                if stderr.contains("already") {
                    tracing::debug!(source = %source, "marketplace already added");
                } else {
                    tracing::warn!(
                        source = %source,
                        status = ?out.status,
                        stderr = %stderr,
                        "claude plugin marketplace add failed (non-fatal)",
                    );
                }
            }
            Err(e) => {
                tracing::warn!(source = %source, error = ?e, "claude plugin marketplace add spawn failed or timed out");
            }
        }
    }
}

/// Read the `services.hyperhive.agent.claudePluginsAutoUpdate` flag written by the NixOS
/// module. Defaults to `false` when the file is absent or unparseable.
async fn auto_update_enabled() -> bool {
    match tokio::fs::read_to_string(AUTO_UPDATE_PATH).await {
        Ok(s) => serde_json::from_str::<bool>(s.trim()).unwrap_or(false),
        Err(_) => false,
    }
}

/// Update all configured plugin marketplaces. Non-fatal — logs a warning
/// on failure but does not abort the install sequence.
async fn update_marketplaces(boot_end: Instant) {
    match run_claude_plugin(&["marketplace", "update"], boot_end).await {
        Ok(out) if out.status.success() => {
            tracing::info!("claude plugin marketplace update ok");
        }
        Ok(out) => {
            tracing::warn!(
                status = ?out.status,
                stderr = %String::from_utf8_lossy(&out.stderr),
                "claude plugin marketplace update failed (non-fatal)",
            );
        }
        Err(e) => {
            tracing::warn!(error = ?e, "claude plugin marketplace update spawn failed or timed out (non-fatal)");
        }
    }
}

/// Install every plugin in `/etc/hyperhive/claude-plugins.json`.
/// A failed install is logged and skipped; the harness starts without it.
pub async fn install_configured() {
    let Ok(raw) = tokio::fs::read_to_string(PLUGINS_PATH).await else {
        return;
    };
    let specs: Vec<String> = match serde_json::from_str(&raw) {
        Ok(v) => v,
        Err(e) => {
            tracing::warn!(path = PLUGINS_PATH, error = ?e, "claude-plugins spec parse failed; skipping");
            return;
        }
    };
    if specs.is_empty() {
        return;
    }
    let boot_end = Instant::now() + PLUGIN_BOOT_BUDGET;
    add_marketplaces(boot_end).await;
    if auto_update_enabled().await {
        update_marketplaces(boot_end).await;
    } else {
        tracing::debug!("claudePluginsAutoUpdate=false, skipping marketplace update");
    }
    for spec in specs {
        match run_claude_plugin(&["install", &spec], boot_end).await {
            Ok(out) if out.status.success() => {
                tracing::info!(spec = %spec, "claude plugin install ok");
            }
            Ok(out) => {
                let stderr = String::from_utf8_lossy(&out.stderr).into_owned();
                tracing::warn!(
                    spec = %spec,
                    status = ?out.status,
                    stderr = %stderr,
                    "claude plugin install failed",
                );
            }
            Err(e) => {
                tracing::warn!(spec = %spec, error = ?e, "claude plugin install spawn failed or timed out");
            }
        }
    }
}

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

    #[tokio::test]
    async fn run_bounded_times_out_a_hung_child() {
        let mut cmd = Command::new("sleep");
        cmd.arg("30");
        let err = run_bounded(cmd, Duration::from_millis(100))
            .await
            .unwrap_err();
        assert_eq!(err.kind(), io::ErrorKind::TimedOut);
    }

    #[tokio::test]
    async fn run_bounded_returns_output_of_a_prompt_child() {
        let cmd = Command::new("true");
        let out = run_bounded(cmd, Duration::from_secs(5)).await;
        assert!(out.unwrap().status.success());
    }

    #[test]
    fn serial_calls_never_exceed_the_boot_budget() {
        let start = Instant::now();
        let boot_end = start + PLUGIN_BOOT_BUDGET;
        let mut now = start;
        // Worst case: every call hangs until its own deadline.
        for _ in 0..50 {
            now += call_budget(now, boot_end);
        }
        assert_eq!(now - start, PLUGIN_BOOT_BUDGET);
        assert_eq!(call_budget(now, boot_end), Duration::ZERO);
    }

    #[test]
    fn a_call_gets_the_full_timeout_while_budget_remains() {
        let start = Instant::now();
        let boot_end = start + PLUGIN_BOOT_BUDGET;
        assert_eq!(call_budget(start, boot_end), PLUGIN_CALL_TIMEOUT);
    }
}