vivac 0.6.4

//! `check` — the `MODEL.md` §9 invariants that apply to Tier 0.
//!
//! It separates two things that look alike and are not. A cycle or an orphan
//! is **store corruption**: the tool is lying. A false close is a **finding
//! about the project**: the store is fine and what is wrong is the work,
//! which was called finished without being finished. Both exit non-zero
//! --this belongs in CI-- but they are not counted together.
//!
//! `--gates` adds a third category, and it follows the same split: the store
//! is fine and **nothing is delivering it**. `d350`/`d351` settled what that
//! means for `MODEL.md` Tier 0 -- the one gate that matters is whether the
//! brief reaches the agent at all, the MCP is not a gate, and it is measured
//! off each project's own log rather than the host's configuration: the hook
//! writes `session.started` when it fires.
//!
//! A project reports here when every node it holds was written before the
//! first session was ever opened -- including a log that never opened one at
//! all. "Zero openings, ever" is not the criterion, and a real tree is why:
//! it held one opening, eight days *after* its last node. That single late
//! opening cleared a "never opened" filter while every node in the tree had
//! in fact been written with no brief in front of anybody.

use crate::args::Args;
use crate::event::{Body, State};
use crate::model::Tree;
use crate::output::outln;

pub fn check(a: &Tree, args: &Args) -> Result<i32, crate::failure::Failure> {
    let mut store: Vec<String> = Vec::new();
    let mut project: Vec<String> = Vec::new();

    if a.broken_lines > 0 {
        store.push(format!(
            "{} unreadable line(s) in .vivac/events (skipped while reading)",
            a.broken_lines
        ));
    }

    // One ULID, one `num`. With `num` as `Tree`'s own storage key, only the
    // first of two claimants ever makes it into `nodes_iter` below -- the
    // fold records the second at the moment it loses, since a scan
    // afterwards has nothing left to see.
    for d in &a.repeated_nums {
        store.push(format!(
            "number {} repeated: {} and {}",
            d.num, d.first, d.second
        ));
    }

    for n in a.nodes_iter() {
        // Invariant 11: provenance is a tree. The schema already rules out two
        // parents --`spawns` travels inside the node-- so the only thing that
        // can break here is the parent not existing.
        if let Some(p) = n.parent {
            if a.node_by_num(p).is_none() {
                store.push(format!(
                    "{} points at a parent that does not exist",
                    n.alias()
                ));
            }
        }
        // Invariant 1: acyclic. If the path to the root does not end at a node
        // with no parent, it is going in circles.
        let lineage = a.ancestors(n.num);
        if lineage.first().is_some_and(|r| r.parent.is_some()) {
            store.push(format!("{} sits in a provenance cycle", n.alias()));
        }
        // Invariant 10: false close.
        //
        // A **forced** close does not count as a violation: `MODEL.md` §9
        // exempts it on purpose, because there are legitimate forced closes
        // --a lane being abandoned-- and what was asked was that they be a
        // decision and not an oversight. The trace is in the event and the
        // render still marks it; what it does not do is break CI every day.
        if n.state == State::Done && !n.forced_close && !a.open_blockers(n.num).is_empty() {
            let pending_count = a.open_blockers(n.num);
            let aliases: Vec<String> = pending_count.iter().map(|c| c.alias()).collect();
            project.push(format!(
                "{} is closed with {} open condition(s): {}",
                n.alias(),
                pending_count.len(),
                aliases.join(", ")
            ));
        }
    }
    store.sort();
    project.sort();

    // Read only when asked: without `--gates` this never touches the
    // registry or any other project's log, and the JSON and the exit code
    // stay exactly what they were before this flag existed.
    let mut gates: Vec<String> = Vec::new();
    if args.has("gates") {
        if let Some(store_dir) = crate::store::store_dir() {
            for root in crate::registry::roots(&store_dir) {
                let Ok(project_store) = crate::store::Store::open(root.clone()) else {
                    continue;
                };
                let Ok((events, _)) = project_store.read_all() else {
                    continue;
                };
                let mut nodes = 0u64;
                let mut before_first_opening = 0u64;
                let mut opened = false;
                for e in &events {
                    match &e.payload {
                        Body::NodeCreated { .. } => {
                            nodes += 1;
                            if !opened {
                                before_first_opening += 1;
                            }
                        }
                        Body::SessionStarted { .. } => opened = true,
                        _ => {}
                    }
                }
                if nodes > 0 && before_first_opening == nodes {
                    gates.push(format!(
                        "{}: {} nodes written, and not one after a session ever opened",
                        crate::render::project_name(&root),
                        nodes
                    ));
                }
            }
        }
        gates.sort();
    }
    let ok = store.is_empty() && project.is_empty() && gates.is_empty();

    if args.has("json") {
        let mut payload = serde_json::json!({
            "store": store,
            "project": project,
            "ok": ok,
        });
        if args.has("gates") {
            if let serde_json::Value::Object(fields) = &mut payload {
                fields.insert("gates".to_string(), serde_json::json!(gates));
            }
        }
        outln!(
            "{}",
            serde_json::to_string_pretty(&payload).map_err(std::io::Error::other)?
        );
    } else {
        outln!();
        if ok {
            outln!("  No findings. {} nodes checked.", a.total());
            outln!();
        }
        if !store.is_empty() {
            outln!(
                "  STORE ({})  <- the tool is lying; it needs fixing",
                store.len()
            );
            outln!();
            for m in &store {
                outln!("      {m}");
            }
            outln!();
        }
        if !project.is_empty() {
            outln!(
                "  PROJECT ({})  <- the store is fine; the work is not",
                project.len()
            );
            outln!();
            for m in &project {
                outln!("      {m}");
            }
            outln!();
            outln!("  A false close is not repaired by editing the tree: reopen what");
            outln!("  stayed open, or close it deliberately with --force.");
            outln!();
        }
        if !gates.is_empty() {
            outln!(
                "  GATES ({})  <- the store is fine; nothing delivers it",
                gates.len()
            );
            outln!();
            for m in &gates {
                outln!("      {m}");
            }
            outln!();
            outln!("  A tree nobody opens is a tree nobody reads. Run  vivac hooks  inside");
            outln!("  that project and paste what it prints.");
            outln!();
        }
    }
    Ok(i32::from(!ok))
}