ljos 0.17.0

//! The prompt hook's judgments through Jev, TypeSafe's decision model, on
//! TypeSafe's own API or OpenRouter's Decisions API: which candidate claims
//! bear on a prompt, whether the prompt corrects the agent, and whether it
//! puts a choice.
//!
//! One request answers all three: the prompt and the candidates are the
//! state, and each judgment is a `noul` question, a probability that the
//! statement is true. Opt-in per machine through `~/.config/ljos/jev.toml`,
//! because the call sends the prompt and the candidate claims off the
//! machine; with no file, no key, a failure or a spent budget, the hook
//! keeps its local path.

use std::collections::BTreeMap;
use std::path::PathBuf;
use std::time::Duration;

use serde_json::Value;

/// `~/.config/ljos/jev.toml`.
#[derive(Debug, Clone, PartialEq, serde::Deserialize)]
pub struct Config {
    /// Off unless set: the call sends the prompt and claims off the machine.
    #[serde(default)]
    pub enabled: bool,
    /// A file holding the key, one line, mode 0600.
    #[serde(default)]
    pub key_file: Option<String>,
    /// A command that prints the key on its first line, such as
    /// `["pass", "show", "api/typesafe/jev"]`; asked once per login and held
    /// in the runtime directory, mode 0600.
    #[serde(default)]
    pub key_cmd: Option<Vec<String>>,
    /// The model: `jev-1.13.0` on TypeSafe's API, `typesafe/jev-1.13` on
    /// OpenRouter's.
    #[serde(default = "default_model")]
    pub model: String,
    /// How long the hook waits for the answer.
    #[serde(default = "default_budget")]
    pub budget_ms: u64,
    /// TypeSafe's endpoint, or `https://openrouter.ai/api/alpha/decisions`.
    #[serde(default = "default_endpoint")]
    pub endpoint: String,
    /// The month's spend, in US dollars, past which the hook stops asking.
    #[serde(default = "default_monthly")]
    pub monthly_usd: f64,
    /// A prompt with fewer words is an acknowledgement ("yes", "keep
    /// going"), with too little in it for a judgment to add anything.
    #[serde(default = "default_min_words")]
    pub min_words: usize,
    /// Fewer candidates than this is nothing to choose between; the local
    /// filters answer.
    #[serde(default = "default_min_candidates")]
    pub min_candidates: usize,
    /// US dollars per million input tokens, for an API whose answer does
    /// not carry its cost. Output is not charged.
    #[serde(default = "default_price_in")]
    pub usd_per_mtok_in: f64,
    /// The probability at which a candidate counts as bearing on the
    /// prompt; higher lets fewer off-topic claims through.
    #[serde(default = "default_cut")]
    pub bears_at: f64,
    /// The probability at which the prompt counts as a correction or a
    /// choice.
    #[serde(default = "default_cut")]
    pub cue_at: f64,
    /// A persona ballot whose confidence is under this goes to a subagent
    /// instead of being cast.
    #[serde(default = "default_escalate")]
    pub escalate_below: f64,
    /// Days an answer is kept and given again for an identical request, at
    /// no cost; 0 turns the cache off. Jev keeps no cache of its own.
    #[serde(default = "default_cache_days")]
    pub cache_days: u64,
}

fn default_model() -> String {
    "jev-1.13.0".into()
}
fn default_budget() -> u64 {
    2000
}
fn default_endpoint() -> String {
    "https://api.typesafe.ai/v1/systemone".into()
}
fn default_monthly() -> f64 {
    4.0
}
fn default_min_words() -> usize {
    4
}
fn default_min_candidates() -> usize {
    2
}
fn default_cache_days() -> u64 {
    7
}
fn default_escalate() -> f64 {
    0.8
}
fn default_cut() -> f64 {
    0.5
}
fn default_price_in() -> f64 {
    0.042
}

/// What a call cost: the API's own figure when it sends one (OpenRouter
/// does), else the input tokens at the configured price.
fn cost_of(body: &Value, usd_per_mtok_in: f64) -> f64 {
    body["usage"]["cost"].as_f64().unwrap_or_else(|| {
        body["usage"]["input_tokens"].as_f64().unwrap_or(0.0) * usd_per_mtok_in / 1e6
    })
}

/// The longest prompt the state carries; a pasted log past it adds cost
/// and no judgment.
const PROMPT_CHARS: usize = 2000;

fn config_path() -> PathBuf {
    std::env::var_os("XDG_CONFIG_HOME")
        .filter(|v| !v.is_empty())
        .map(PathBuf::from)
        .or_else(|| std::env::var_os("HOME").map(|h| PathBuf::from(h).join(".config")))
        .unwrap_or_else(|| PathBuf::from(".config"))
        .join("ljos")
        .join("jev.toml")
}

fn expand(path: &str) -> PathBuf {
    match path.strip_prefix("~/") {
        Some(rest) => std::env::var_os("HOME")
            .map_or_else(|| PathBuf::from(path), |h| PathBuf::from(h).join(rest)),
        None => PathBuf::from(path),
    }
}

fn read_config() -> Option<Config> {
    let text = std::fs::read_to_string(config_path()).ok()?;
    toml::from_str(&text).ok()
}

/// Whether this machine turned Jev on, key or not. The hook's local path
/// then skips the cross-encoder, which is what Jev stands in for.
#[must_use]
pub fn enabled() -> bool {
    read_config().is_some_and(|c| c.enabled)
}

/// The key from the first line of what a key file or command holds. A
/// `name: value` or `name=value` line gives its value.
fn key_from(text: &str) -> Option<String> {
    let line = text.lines().next()?.trim();
    let value = line
        .rsplit(|c: char| c == ':' || c == '=' || c.is_whitespace())
        .next()
        .unwrap_or(line)
        .trim();
    (!value.is_empty()).then(|| value.to_string())
}

fn key_cache() -> Option<PathBuf> {
    let dir = std::env::var_os("XDG_RUNTIME_DIR").filter(|v| !v.is_empty())?;
    Some(PathBuf::from(dir).join("ljos").join("jev-key"))
}

/// Run the key command once, with no terminal to prompt on and three
/// seconds to answer, and hold what it printed for the rest of the login.
fn key_by_command(argv: &[String]) -> Option<String> {
    use std::io::Write;
    use std::os::unix::fs::OpenOptionsExt;
    let cache = key_cache();
    if let Some(key) = cache
        .as_ref()
        .and_then(|p| std::fs::read_to_string(p).ok())
        .and_then(|t| key_from(&t))
    {
        return Some(key);
    }
    let (prog, args) = argv.split_first()?;
    let out = std::process::Command::new("timeout")
        .arg("3")
        .arg(prog)
        .args(args)
        .stdin(std::process::Stdio::null())
        .stderr(std::process::Stdio::null())
        .output()
        .ok()?;
    if !out.status.success() {
        return None;
    }
    let key = key_from(&String::from_utf8_lossy(&out.stdout))?;
    if let Some(path) = cache {
        let _ = std::fs::create_dir_all(path.parent()?);
        if let Ok(mut f) = std::fs::OpenOptions::new()
            .write(true)
            .create(true)
            .truncate(true)
            .mode(0o600)
            .open(&path)
        {
            let _ = writeln!(f, "{key}");
        }
    }
    Some(key)
}

/// The machine's Jev setting, when it turned Jev on, its key is there and
/// the month's spend is under its cap.
#[must_use]
pub fn config() -> Option<(Config, String)> {
    let cfg = read_config()?;
    if !cfg.enabled || month_cost().unwrap_or(0.0) >= cfg.monthly_usd {
        return None;
    }
    let key = match (&cfg.key_cmd, &cfg.key_file) {
        (Some(argv), _) => key_by_command(argv)?,
        (None, Some(file)) => key_from(&std::fs::read_to_string(expand(file)).ok()?)?,
        (None, None) => return None,
    };
    Some((cfg, key))
}

/// What Jev said about one prompt.
#[derive(Debug, Clone, Default, PartialEq)]
pub struct Judgment {
    /// Probability that each candidate, by its index, bears on the prompt.
    pub bears: Vec<f64>,
    /// Probability the prompt corrects something the agent did or forgot.
    pub correction: f64,
    /// Probability the prompt puts a choice between options to the agent.
    pub choice: f64,
    /// What the call cost, in US dollars.
    pub cost: f64,
    /// The machine's cut for `bears`.
    pub bears_at: f64,
    /// The machine's cut for `correction` and `choice`.
    pub cue_at: f64,
}

impl Judgment {
    /// Whether candidate `i` bears on the prompt at the machine's cut.
    #[must_use]
    pub fn bears(&self, i: usize) -> bool {
        self.bears.get(i).is_some_and(|p| *p >= self.bears_at)
    }
}

/// The request body: the prompt and numbered candidates as state, one
/// `noul` per candidate and one each for a correction and a choice.
#[must_use]
pub fn request(model: &str, prompt: &str, candidates: &[&str]) -> Value {
    let prompt: String = prompt.chars().take(PROMPT_CHARS).collect();
    let mut state = format!("Prompt from the person to the agent:\n{prompt}\n\nStored claims:\n");
    for (i, text) in candidates.iter().enumerate() {
        state.push_str(&format!("[{i}] {text}\n"));
    }
    let mut questions = serde_json::Map::new();
    for i in 0..candidates.len() {
        questions.insert(
            format!("bears_{i}"),
            serde_json::json!({
                "type": "noul",
                "instructions": format!("Does stored claim [{i}] bear on what the prompt asks the agent to do now?"),
                "criteria": {
                    "true": "The claim changes or informs how the agent should act on this prompt",
                    "false": "The claim is about something else, or only shares words with the prompt"
                }
            }),
        );
    }
    questions.insert(
        "correction".into(),
        serde_json::json!({
            "type": "noul",
            "instructions": "Does the person correct the agent for something it did, forgot or was already told?",
            "criteria": {
                "true": "The prompt tells the agent it was wrong or should already know",
                "false": "The prompt asks for work or information without correcting the agent"
            }
        }),
    );
    questions.insert(
        "choice".into(),
        serde_json::json!({
            "type": "noul",
            "instructions": "Does the prompt put to the agent a choice between two or more defensible options?",
            "criteria": {
                "true": "The person asks which of several ways to take, or weighs options",
                "false": "The person names one thing to do, or asks a factual question"
            }
        }),
    );
    serde_json::json!({ "model": model, "state": state, "questions": questions })
}

/// Read the answers into a judgment; `None` when a question went
/// unanswered, so the caller falls back rather than trusting half an answer.
#[must_use]
pub fn parse(body: &Value, candidates: usize) -> Option<Judgment> {
    let answers = body.get("answers")?.as_object()?;
    let noul = |key: &str| answers.get(key)?.get("noul")?.as_f64();
    let bears: Vec<f64> = (0..candidates)
        .map(|i| noul(&format!("bears_{i}")))
        .collect::<Option<_>>()?;
    Some(Judgment {
        bears,
        correction: noul("correction")?,
        choice: noul("choice")?,
        cost: 0.0,
        bears_at: 0.5,
        cue_at: 0.5,
    })
}

/// Send one request inside the configured budget, record its cost and
/// log its answers; the answers object, or `None` on any failure.
fn post(cfg: &Config, key: &str, body: Value, kind: &str, about: Value) -> Option<Value> {
    let request = format!("{}\n{body}", cfg.endpoint);
    if let Some(reply) = cached(&request, cfg.cache_days) {
        count("cached");
        return Some(reply);
    }
    let reply: Value = ureq::post(&cfg.endpoint)
        .timeout(Duration::from_millis(cfg.budget_ms))
        .set("Authorization", &format!("Bearer {key}"))
        .set("Content-Type", "application/json")
        .send_json(body)
        .ok()?
        .into_json()
        .ok()?;
    let answers = reply.get("answers")?.clone();
    let cost = cost_of(&reply, cfg.usd_per_mtok_in);
    record_cost(cost);
    if cfg.cache_days > 0 {
        keep(&request, &reply);
    }
    log(&serde_json::json!({
        "ts": crate::now_utc(),
        "kind": kind,
        "model": cfg.model,
        "about": about,
        "answers": answers,
        "cost": cost,
    }));
    Some(reply)
}

/// Ask Jev about one prompt, inside the configured budget.
#[must_use]
pub fn judge(prompt: &str, candidates: &[&str]) -> Option<Judgment> {
    let (cfg, key) = config()?;
    let body = request(&cfg.model, prompt, candidates);
    let reply = post(&cfg, &key, body, "hook", Value::Null)?;
    let mut judged = parse(&reply, candidates.len())?;
    judged.cost = cost_of(&reply, cfg.usd_per_mtok_in);
    judged.bears_at = cfg.bears_at;
    judged.cue_at = cfg.cue_at;
    Some(judged)
}

/// A persona's ballot as Jev answered it: the choice with its confidence
/// and the probability of every option, and its forecast of the share each
/// option gets from the rest of the panel.
#[derive(Debug, Clone, PartialEq)]
pub struct Ballot {
    pub choice: String,
    pub confidence: f64,
    pub probabilities: BTreeMap<String, f64>,
    pub forecast: BTreeMap<String, f64>,
    /// The machine's cut under which the ballot goes to a subagent.
    pub escalate_below: f64,
}

impl Ballot {
    /// Whether Jev is too unsure for its answer to stand as the ballot.
    #[must_use]
    pub fn escalates(&self) -> bool {
        self.confidence < self.escalate_below
    }
}

/// The ballot request: the persona's brief as state, one `choice` for its
/// own vote and one for what the rest of the panel will pick.
#[must_use]
pub fn ballot_request(model: &str, brief: &str, options: &[String]) -> Value {
    let criteria = |verb: &str| -> Value {
        options
            .iter()
            .map(|o| (o.clone(), Value::String(format!("{verb} {o}"))))
            .collect::<serde_json::Map<_, _>>()
            .into()
    };
    serde_json::json!({
        "model": model,
        "state": brief,
        "questions": {
            "ballot": {
                "type": "choice",
                "instructions": "You are the persona the state describes. Which option do you vote for, from your own view and what you know?",
                "criteria": criteria("vote for"),
            },
            "forecast": {
                "type": "choice",
                "instructions": "Which option will most of the other reviewers on this panel vote for?",
                "criteria": criteria("most others pick"),
            },
        }
    })
}

/// Read a ballot answer; `None` when either question went unanswered or
/// the choice is not one of the options.
#[must_use]
pub fn parse_ballot(body: &Value, options: &[String]) -> Option<Ballot> {
    let answers = body.get("answers")?;
    let probs = |key: &str| -> Option<BTreeMap<String, f64>> {
        let map = answers.get(key)?.get("probabilities")?.as_object()?;
        Some(
            map.iter()
                .filter_map(|(k, v)| Some((k.clone(), v.as_f64()?)))
                .collect(),
        )
    };
    let ballot = answers.get("ballot")?;
    let choice = ballot.get("choice")?.as_str()?.to_string();
    if !options.contains(&choice) {
        return None;
    }
    Some(Ballot {
        confidence: ballot.get("confidence")?.as_f64()?,
        probabilities: probs("ballot")?,
        forecast: probs("forecast")?,
        choice,
        escalate_below: 0.8,
    })
}

/// Ask Jev for a persona's ballot on an issue.
#[must_use]
pub fn ballot(persona: &str, issue: &str, brief: &str, options: &[String]) -> Option<Ballot> {
    let (cfg, key) = config()?;
    let body = ballot_request(&cfg.model, brief, options);
    let about = serde_json::json!({"issue": issue, "persona": persona, "options": options});
    let reply = post(&cfg, &key, body, "ballot", about)?;
    let mut b = parse_ballot(&reply, options)?;
    b.escalate_below = cfg.escalate_below;
    Some(b)
}

/// `$XDG_CACHE_HOME/ljos/jev`, one file per request.
fn cache_dir() -> Option<PathBuf> {
    Some(
        std::env::var_os("XDG_CACHE_HOME")
            .filter(|v| !v.is_empty())
            .map(PathBuf::from)
            .or_else(|| std::env::var_os("HOME").map(|h| PathBuf::from(h).join(".cache")))?
            .join("ljos")
            .join("jev"),
    )
}

/// The file an identical request lands in. The hash only names the file;
/// the file holds the whole request, and a hit must match it exactly.
fn cache_file(request: &str) -> Option<PathBuf> {
    use std::hash::{Hash, Hasher};
    let mut h = std::collections::hash_map::DefaultHasher::new();
    request.hash(&mut h);
    Some(cache_dir()?.join(format!("{:016x}.json", h.finish())))
}

/// The answer to an identical request made within `days`.
fn cached(request: &str, days: u64) -> Option<Value> {
    if days == 0 {
        return None;
    }
    let path = cache_file(request)?;
    let age = std::fs::metadata(&path)
        .ok()?
        .modified()
        .ok()?
        .elapsed()
        .ok()?;
    if age > Duration::from_secs(days * 86_400) {
        let _ = std::fs::remove_file(&path);
        return None;
    }
    let entry: Value = serde_json::from_str(&std::fs::read_to_string(&path).ok()?).ok()?;
    (entry["request"].as_str() == Some(request)).then(|| entry["reply"].clone())
}

fn keep(request: &str, reply: &Value) {
    let Some(path) = cache_file(request) else {
        return;
    };
    if let Some(dir) = path.parent() {
        let _ = std::fs::create_dir_all(dir);
    }
    let entry = serde_json::json!({"request": request, "reply": reply});
    let _ = std::fs::write(path, entry.to_string());
}

/// Add one to this month's tally named `what` (`calls`, `cached`).
fn count(what: &str) {
    let Some(dir) = state_dir() else { return };
    let _ = std::fs::create_dir_all(&dir);
    let path = dir.join("jev-cost.toml");
    let mut totals: BTreeMap<String, f64> = std::fs::read_to_string(&path)
        .ok()
        .and_then(|t| toml::from_str(&t).ok())
        .unwrap_or_default();
    *totals
        .entry(format!("{}-{what}", this_month()))
        .or_default() += 1.0;
    if let Ok(text) = toml::to_string(&totals) {
        let _ = std::fs::write(path, text);
    }
}

/// The stop audit's cuts. A stop is held back only on a near-certain
/// answer: the model is asked about the agent's own words, and a false
/// block costs the person a turn.
pub const AUDIT_CLAIM_AT: f64 = 0.9;
/// The test run shown counts as red at or under this.
pub const AUDIT_RED_BELOW: f64 = 0.1;
/// The final message counts as deferring asked work at or over this.
pub const AUDIT_DEFER_AT: f64 = 0.9;

/// What Jev said about an agent about to stop.
#[derive(Debug, Clone, Copy, PartialEq)]
pub struct Audit {
    /// The final message claims the work is done, passing or ready.
    pub claims_complete: f64,
    /// The last test output shown passes with no failure.
    pub tests_green: f64,
    /// The final message puts part of the asked work off, or out of scope.
    pub deferral: f64,
}

/// The audit request: the turn as state, three nouls.
#[must_use]
pub fn audit_request(model: &str, state: &str) -> Value {
    serde_json::json!({
        "model": model,
        "state": state,
        "questions": {
            "claims_complete": {
                "type": "noul",
                "instructions": "Does the agent's final message claim the asked work is done, complete, passing, green or ready?",
                "criteria": {
                    "true": "It says the work is finished or the tests pass",
                    "false": "It reports progress, a failure, a question or what is still open"
                }
            },
            "tests_green": {
                "type": "noul",
                "instructions": "Does the most recent test output in the state pass, with no failed, errored or crashed test?",
                "criteria": {
                    "true": "The latest run reports every test passing",
                    "false": "The latest run reports a failure, an error, a crash or a build that did not finish"
                }
            },
            "deferral": {
                "type": "noul",
                "instructions": "Does the final message put part of what the person asked off to later, or call it out of scope, without naming something outside the agent's control that blocks it?",
                "criteria": {
                    "true": "It leaves asked work for a later change, session or person, with no external block",
                    "false": "It finishes the asked work, or names a real block such as a missing credential or a failing external service"
                }
            }
        }
    })
}

/// Read the audit; `None` on a partial answer.
#[must_use]
pub fn parse_audit(body: &Value) -> Option<Audit> {
    let a = body.get("answers")?;
    let noul = |k: &str| a.get(k)?.get("noul")?.as_f64();
    Some(Audit {
        claims_complete: noul("claims_complete")?,
        tests_green: noul("tests_green")?,
        deferral: noul("deferral")?,
    })
}

/// Ask Jev about a turn that is about to end.
#[must_use]
pub fn audit(state: &str) -> Option<Audit> {
    let (cfg, key) = config()?;
    let body = audit_request(&cfg.model, state);
    let reply = post(&cfg, &key, body, "stop-audit", Value::Null)?;
    parse_audit(&reply)
}

/// Why a stop is held back, from the audit and whether a test ran in the
/// turn; `None` lets the agent stop.
#[must_use]
pub fn audit_reason(a: &Audit, test_ran: bool) -> Option<String> {
    if test_ran && a.claims_complete >= AUDIT_CLAIM_AT && a.tests_green <= AUDIT_RED_BELOW {
        return Some(
            "The final message says the work is done, and the last test run shown is red. \
             Say what still fails, or fix it, before stopping."
                .to_string(),
        );
    }
    if a.deferral >= AUDIT_DEFER_AT {
        return Some(
            "The final message leaves part of the asked work for later without naming what blocks it. \
             Do that part, or say in one sentence what outside the work blocks it."
                .to_string(),
        );
    }
    None
}

fn state_dir() -> Option<PathBuf> {
    Some(
        std::env::var_os("XDG_STATE_HOME")
            .filter(|v| !v.is_empty())
            .map(PathBuf::from)
            .or_else(|| std::env::var_os("HOME").map(|h| PathBuf::from(h).join(".local/state")))?
            .join("ljos"),
    )
}

/// Every answer Jev gave, one JSON line each in the state directory, so
/// its probabilities can be scored once the outcomes are known.
fn log(entry: &Value) {
    use std::io::Write;
    let Some(dir) = state_dir() else { return };
    let _ = std::fs::create_dir_all(&dir);
    if let Ok(mut f) = std::fs::OpenOptions::new()
        .create(true)
        .append(true)
        .open(dir.join("jev-log.jsonl"))
    {
        let _ = writeln!(f, "{entry}");
    }
}

/// Add a call's cost to this month's running total in the state directory,
/// so `ljos doctor` can say what Jev has cost.
fn record_cost(cost: f64) {
    let Some(dir) = state_dir() else { return };
    let _ = std::fs::create_dir_all(&dir);
    let month = crate::now_utc().chars().take(7).collect::<String>();
    let path = dir.join("jev-cost.toml");
    let mut totals: BTreeMap<String, f64> = std::fs::read_to_string(&path)
        .ok()
        .and_then(|t| toml::from_str(&t).ok())
        .unwrap_or_default();
    *totals.entry(format!("{month}-calls")).or_default() += 1.0;
    *totals.entry(month).or_default() += cost;
    if let Ok(text) = toml::to_string(&totals) {
        let _ = std::fs::write(path, text);
    }
}

fn month_totals() -> Option<BTreeMap<String, f64>> {
    let dir = state_dir()?;
    let text = std::fs::read_to_string(dir.join("jev-cost.toml")).ok()?;
    toml::from_str(&text).ok()
}

fn this_month() -> String {
    crate::now_utc().chars().take(7).collect()
}

/// This month's recorded Jev spend, in US dollars.
#[must_use]
pub fn month_cost() -> Option<f64> {
    month_totals()?.get(&this_month()).copied()
}

/// This month's tally named `what`: `calls` made, `cached` answered from
/// the cache.
#[must_use]
pub fn month_count(what: &str) -> u64 {
    month_totals()
        .and_then(|t| t.get(&format!("{}-{what}", this_month())).copied())
        .unwrap_or(0.0) as u64
}

/// How many calls this month made.
#[must_use]
pub fn month_calls() -> u64 {
    month_count("calls")
}

/// The `jev` row in `ljos doctor`, only on a machine with a Jev file: off,
/// on without its key, or on with this month's spend. A setting that does
/// not parse is not ok, since the hook then keeps its local path silently.
#[must_use]
pub fn doctor_row() -> Option<crate::Habitat> {
    let text = std::fs::read_to_string(config_path()).ok()?;
    let (state, ok) = match toml::from_str::<Config>(&text) {
        Err(e) => (format!("{}: {e}", config_path().display()), false),
        Ok(cfg) if !cfg.enabled => ("off".to_string(), true),
        Ok(cfg) => {
            let spent = month_cost().unwrap_or(0.0);
            let head = format!(
                "{}  {} calls, {} cached  ${spent:.4} of ${:.2} this month",
                cfg.model,
                month_calls(),
                month_count("cached"),
                cfg.monthly_usd
            );
            if spent >= cfg.monthly_usd {
                (format!("capped  {head}"), true)
            } else if config().is_none() {
                (
                    "on, but the key file or command gave no key".to_string(),
                    false,
                )
            } else {
                (format!("on  {head}"), true)
            }
        }
    };
    Some(crate::Habitat {
        name: "jev",
        state,
        ok,
    })
}

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

    #[test]
    fn one_request_asks_about_every_candidate_and_both_cues() {
        let body = request("jev-1.13.0", "fix the ci", &["alpha claim", "beta claim"]);
        let q = body["questions"].as_object().unwrap();
        assert_eq!(q.len(), 4);
        assert_eq!(q["bears_1"]["type"], "noul");
        assert!(body["state"].as_str().unwrap().contains("[1] beta claim"));
    }

    #[test]
    fn a_full_answer_is_read_and_a_partial_one_is_refused() {
        let full = serde_json::json!({
            "answers": {
                "bears_0": {"type": "noul", "noul": 0.9},
                "bears_1": {"type": "noul", "noul": 0.1},
                "correction": {"type": "noul", "noul": 0.2},
                "choice": {"type": "noul", "noul": 0.7}
            },
            "usage": {"input_tokens": 900, "output_tokens": 40, "cost": 0.0000378}
        });
        let j = parse(&full, 2).unwrap();
        assert_eq!(j.bears, vec![0.9, 0.1]);
        assert!(j.bears(0) && !j.bears(1));
        let strict = Judgment {
            bears_at: 0.95,
            ..j.clone()
        };
        assert!(!strict.bears(0), "a higher cut drops the 0.9");
        assert!((j.choice - 0.7).abs() < 1e-9);
        assert!(
            (cost_of(&full, 0.042) - 0.0000378).abs() < 1e-12,
            "the API's figure"
        );
        let direct = serde_json::json!({"usage": {"input_tokens": 1000, "output_tokens": 60}});
        assert!(
            (cost_of(&direct, 0.042) - 0.000042).abs() < 1e-12,
            "tokens at the price"
        );
        let partial = serde_json::json!({"answers": {"bears_0": {"noul": 0.9}}});
        assert!(parse(&partial, 2).is_none());
    }

    #[test]
    fn jev_is_off_without_a_file_and_off_when_the_file_says_so() {
        let dir = tempfile::tempdir().unwrap();
        // Safety: the test sets and clears this for itself.
        unsafe { std::env::set_var("XDG_CONFIG_HOME", dir.path()) };
        assert!(config().is_none(), "no file, no call");
        std::fs::create_dir_all(dir.path().join("ljos")).unwrap();
        let key = dir.path().join("key");
        std::fs::write(&key, "sk-or-test\n").unwrap();
        std::fs::write(
            dir.path().join("ljos/jev.toml"),
            format!("enabled = false\nkey_file = \"{}\"\n", key.display()),
        )
        .unwrap();
        assert!(config().is_none(), "a file that says off is off");
        std::fs::write(
            dir.path().join("ljos/jev.toml"),
            format!("enabled = true\nkey_file = \"{}\"\n", key.display()),
        )
        .unwrap();
        let (cfg, k) = config().unwrap();
        assert_eq!(k, "sk-or-test");
        assert_eq!(cfg.budget_ms, 2000);
        assert_eq!(cfg.min_candidates, 2);
        unsafe { std::env::remove_var("XDG_CONFIG_HOME") };
    }

    #[test]
    fn a_key_line_gives_its_value() {
        assert_eq!(key_from("sk-or-v1-abc\n").as_deref(), Some("sk-or-v1-abc"));
        assert_eq!(
            key_from("apikey: sk-or-v1-abc\nurl: x\n").as_deref(),
            Some("sk-or-v1-abc")
        );
        assert_eq!(
            key_from("apikey=sk-or-v1-abc").as_deref(),
            Some("sk-or-v1-abc")
        );
        assert_eq!(key_from("\n"), None);
    }

    #[test]
    fn a_ballot_carries_its_confidence_and_forecast_and_escalates_under_the_cut() {
        let options = vec!["age".to_string(), "gpg".to_string()];
        let body = ballot_request("jev-1.13.0", "You are brio.", &options);
        assert_eq!(body["questions"]["ballot"]["type"], "choice");
        assert_eq!(
            body["questions"]["forecast"]["criteria"]["gpg"],
            "most others pick gpg"
        );
        let reply = serde_json::json!({"answers": {
            "ballot": {"type": "choice", "choice": "age", "confidence": 0.97,
                       "probabilities": {"age": 0.98, "gpg": 0.02}},
            "forecast": {"type": "choice", "choice": "age", "confidence": 0.95,
                         "probabilities": {"age": 0.97, "gpg": 0.03}}}});
        let b = parse_ballot(&reply, &options).unwrap();
        assert_eq!(b.choice, "age");
        assert!(!b.escalates(), "0.97 stands at the 0.8 cut");
        assert!((b.forecast["gpg"] - 0.03).abs() < 1e-9);
        let unsure = Ballot {
            confidence: 0.6,
            ..b.clone()
        };
        assert!(unsure.escalates(), "0.6 goes to a subagent");
        let off = serde_json::json!({"answers": {
            "ballot": {"choice": "rsa", "confidence": 0.9, "probabilities": {}},
            "forecast": {"choice": "age", "confidence": 0.9, "probabilities": {}}}});
        assert!(
            parse_ballot(&off, &options).is_none(),
            "a choice off the list is refused"
        );
    }

    #[test]
    fn an_identical_request_is_answered_from_the_cache_and_only_that_one() {
        let dir = tempfile::tempdir().unwrap();
        // Safety: the test sets and clears this for itself.
        unsafe { std::env::set_var("XDG_CACHE_HOME", dir.path()) };
        let reply = serde_json::json!({"answers": {"x": {"noul": 0.9}}});
        assert!(cached("req-a", 7).is_none(), "nothing kept yet");
        keep("req-a", &reply);
        assert_eq!(cached("req-a", 7), Some(reply));
        assert!(cached("req-b", 7).is_none(), "another request misses");
        assert!(cached("req-a", 0).is_none(), "0 days is off");
        unsafe { std::env::remove_var("XDG_CACHE_HOME") };
    }

    #[test]
    fn a_stop_is_held_only_on_done_beside_red_or_an_open_deferral() {
        let a = |c: f64, g: f64, d: f64| Audit {
            claims_complete: c,
            tests_green: g,
            deferral: d,
        };
        assert!(
            audit_reason(&a(0.95, 0.05, 0.1), true).is_some(),
            "done beside red"
        );
        assert!(
            audit_reason(&a(0.95, 0.05, 0.1), false).is_none(),
            "no test ran, nothing to be red"
        );
        assert!(
            audit_reason(&a(0.95, 0.9, 0.1), true).is_none(),
            "done beside green"
        );
        assert!(
            audit_reason(&a(0.5, 0.05, 0.1), true).is_none(),
            "a red run reported as red"
        );
        assert!(
            audit_reason(&a(0.2, 0.9, 0.95), false).is_some(),
            "work put off"
        );
        let reply = serde_json::json!({"answers": {
            "claims_complete": {"noul": 0.9}, "tests_green": {"noul": 0.1}, "deferral": {"noul": 0.0}}});
        assert_eq!(parse_audit(&reply), Some(a(0.9, 0.1, 0.0)));
        assert_eq!(
            audit_request("m", "s")["questions"]
                .as_object()
                .unwrap()
                .len(),
            3
        );
    }
}