kyyn-core 0.1.13

//! Registry-driven generic validation — everything a schema DECLARES, the
//! engine can CHECK without the schema crate hand-writing it:
//!
//! - routing + parse: storage patterns say where records live; typed decode
//!   (dates, decimals, enums, links) says whether one reads back (Error).
//! - placeholder consistency: a field named like a storage placeholder must
//!   match its path segment — `id` vs filename, `person` vs directory (Error).
//! - link policy: `Link { allowed }` fields reject other kinds (Error);
//!   KB-native links that do not resolve warn; declared external systems
//!   pass; unrecognized heads warn. Enum-payload links included.
//! - `refers_to`: a plain-string slug must name a known record (Warning).
//! - inline `[[…]]` links in every Markdown field resolve or warn.
//!
//! A schema crate calls [`against_registry`] and appends only its own
//! cross-record invariants — the registry IS the declarative source; this
//! module is its interpreter. Severity doctrine: malformed shape and policy
//! breaches block an accept (Error); unresolvable references warn.

use std::collections::{HashMap, HashSet};

use crate::link::Link;
use crate::registry::{Field, FieldType, Kind, Registry};
use crate::storage::{match_storage, route};
use crate::value::{Value, decode};
use crate::violation::{Severity, Violation};

/// Validate every entry a registry can judge. `entries` are (repo-relative
/// path, RON text) pairs; paths outside `facts/` are ignored.
pub fn against_registry(
    registry: &Registry,
    entries: &[(String, String)],
    systems: &[&str],
) -> Vec<Violation> {
    let mut out = Vec::new();
    let id_kinds: Vec<&str> = registry
        .kinds
        .iter()
        .filter(|k| k.storage.contains('{'))
        .map(|k| k.name.as_str())
        .collect();
    let singleton_kinds: Vec<&str> = registry
        .kinds
        .iter()
        .filter(|k| !k.storage.contains('{'))
        .map(|k| k.name.as_str())
        .collect();

    // Pass 1: route and decode. A facts/ path no pattern claims is an Error;
    // so is a record that fails its kind's typed decode (malformed dates and
    // decimals fail HERE — shape is parse, not a later step).
    struct Parsed<'r> {
        path: String,
        kind: &'r Kind,
        id: Option<String>,
        value: std::collections::BTreeMap<String, Value>,
    }
    let mut parsed: Vec<Parsed> = Vec::new();
    for (path, text) in entries {
        if !path.starts_with("facts/") {
            continue;
        }
        match route(registry, path) {
            None => out.push(Violation {
                path: path.clone(),
                severity: Severity::Error,
                message: format!(
                    "not a recognised KB path for this schema (expected one of: {})",
                    registry
                        .kinds
                        .iter()
                        .map(|k| k.storage.as_str())
                        .collect::<Vec<_>>()
                        .join(", ")
                ),
            }),
            Some((kind, id)) => match decode(kind, text) {
                Err(e) => out.push(Violation {
                    path: path.clone(),
                    severity: Severity::Error,
                    message: format!("does not parse as a {}: {e}", kind.name),
                }),
                Ok(value) => parsed.push(Parsed {
                    path: path.clone(),
                    kind,
                    id,
                    value,
                }),
            },
        }
    }

    // The id universes links resolve against — route-derived, so they are
    // exactly the ids other records can address.
    let mut universe = Universe {
        ids: id_kinds
            .iter()
            .map(|k| (k.to_string(), HashSet::new()))
            .collect(),
        singletons_present: HashSet::new(),
    };
    for p in &parsed {
        match &p.id {
            Some(id) => {
                universe
                    .ids
                    .get_mut(p.kind.name.as_str())
                    .expect("seeded")
                    .insert(id.clone());
            }
            None => {
                universe.singletons_present.insert(p.kind.name.clone());
            }
        }
    }

    // Pass 2: per-record invariants, walked from the declared field types.
    for p in &parsed {
        let mut check = Checker {
            path: &p.path,
            universe: &universe,
            systems,
            id_kinds: &id_kinds,
            singleton_kinds: &singleton_kinds,
            out: &mut out,
        };
        // Placeholder consistency: each `{name}` binds a path segment; a
        // record field of the same name must agree with it.
        if let Some(id) = &p.id
            && let Some(bindings) = match_storage(&p.kind.storage, &p.path)
        {
            let names = placeholder_names(&p.kind.storage);
            let n = names.len();
            for (i, (name, segment)) in names
                .iter()
                .zip(&bindings)
                .collect::<Vec<_>>()
                .into_iter()
                .enumerate()
            {
                let Some(v) = p.value.get(name.as_str()) else {
                    continue;
                };
                let rendered = match v {
                    Value::Str(s) => s.clone(),
                    Value::Date(d) => d.to_string(),
                    _ => continue,
                };
                if &rendered != segment {
                    let position = if i + 1 == n { "filename" } else { "directory" };
                    check.error(format!(
                        "{name} '{rendered}' does not match {position} '{segment}'"
                    ));
                }
            }
            let _ = id;
        }
        for field in &p.kind.fields {
            if let Some(v) = p.value.get(&field.name) {
                check.walk(&field.name, &field.ty, v, field.refers_to.as_deref());
            }
        }
    }
    out
}

/// The names of a storage pattern's placeholders, in path order.
fn placeholder_names(pattern: &str) -> Vec<String> {
    pattern
        .split('/')
        .filter_map(|seg| {
            let open = seg.find('{')?;
            let close = seg.find('}')?;
            (open < close).then(|| seg[open + 1..close].to_string())
        })
        .collect()
}

/// The id universes KB links resolve against.
struct Universe {
    ids: HashMap<String, HashSet<String>>,
    singletons_present: HashSet<String>,
}

impl Universe {
    /// If `link` is KB-native and does not resolve, say why (a Warning).
    /// External links (a declared system) are not locally resolvable.
    fn unresolved(&self, link: &Link, systems: &[&str]) -> Option<String> {
        let p = link.parts(systems);
        if p.is_external() {
            return None;
        }
        if let Some(set) = self.ids.get(p.kind) {
            return match p.id {
                Some(id) if set.contains(id) => None,
                Some(_) => Some(format!(
                    "link '{link}' does not resolve to a known {}",
                    p.kind
                )),
                None => Some(format!(
                    "link '{link}' names kind '{}' without an id",
                    p.kind
                )),
            };
        }
        Some(format!("unrecognized link '{link}'"))
    }

    fn unresolved_singleton(&self, link: &Link, kind: &str, id: Option<&str>) -> Option<String> {
        match id {
            None if self.singletons_present.contains(kind) => None,
            None => Some(format!(
                "link '{link}' does not resolve: no {kind} record present"
            )),
            Some(_) => Some(format!("singleton kind '{kind}' takes no id")),
        }
    }
}

/// Per-file check helper carrying the path, universe and declared systems.
struct Checker<'a> {
    path: &'a str,
    universe: &'a Universe,
    systems: &'a [&'a str],
    id_kinds: &'a [&'a str],
    singleton_kinds: &'a [&'a str],
    out: &'a mut Vec<Violation>,
}

impl Checker<'_> {
    fn push(&mut self, severity: Severity, message: String) {
        self.out.push(Violation {
            path: self.path.to_string(),
            severity,
            message,
        });
    }

    fn error(&mut self, message: String) {
        self.push(Severity::Error, message);
    }

    fn warn(&mut self, message: String) {
        self.push(Severity::Warning, message);
    }

    /// Resolution with singleton awareness — the one seam Universe splits on.
    fn resolve(&mut self, prefix: &str, link: &Link) {
        let p = link.parts(self.systems);
        let msg = if self.singleton_kinds.contains(&p.kind) && !p.is_external() {
            self.universe.unresolved_singleton(link, p.kind, p.id)
        } else {
            self.universe.unresolved(link, self.systems)
        };
        if let Some(msg) = msg {
            self.warn(format!("{prefix}{msg}"));
        }
    }

    /// The uniform link policy: a disallowed kind is an Error; an
    /// unresolvable / unrecognized link is a Warning.
    fn link(&mut self, field: &str, link: &Link, allowed: Option<&[String]>) {
        let p = link.parts(self.systems);
        if let Some(kinds) = allowed {
            // Policy matches the namespace (system for external links, kind
            // for native ones). An *unrecognized* head isn't a kind violation
            // — it's an unknown, warned below.
            if p.recognized(self.id_kinds, self.singleton_kinds)
                && !kinds.iter().any(|k| k == p.namespace())
            {
                self.error(format!(
                    "{field} '{link}' has kind '{}' (allowed: {})",
                    p.namespace(),
                    kinds.join(", ")
                ));
                return;
            }
        }
        self.resolve(&format!("{field}: "), link);
    }

    /// Inline `[[…]]` links in prose: an unresolvable KB-kind link is a
    /// Warning. Bracketed text whose head is no known kind is left alone —
    /// prose is prose.
    fn inline(&mut self, text: &str) {
        for l in Link::find_inline(text) {
            let p = l.parts(self.systems);
            if !p.recognized(self.id_kinds, self.singleton_kinds) {
                continue;
            }
            self.resolve("inline ", &l);
        }
    }

    /// Walk a decoded value with its declared type, checking every link,
    /// prose store and refers_to slug — enum payloads and nested structs
    /// included, so a Link is checked wherever the schema can put one.
    fn walk(&mut self, field: &str, ty: &FieldType, v: &Value, refers_to: Option<&str>) {
        match (ty, v) {
            (FieldType::Link { allowed }, Value::Link(l)) => {
                self.link(field, l, allowed.as_deref());
            }
            (FieldType::Markdown, Value::Str(s)) => self.inline(s),
            (FieldType::Str, Value::Str(s)) => {
                if let Some(target) = refers_to
                    && let Some(set) = self.universe.ids.get(target)
                    && !set.contains(s)
                {
                    self.warn(format!("{field} '{s}' is not a known {target}"));
                }
            }
            (FieldType::Option(inner), v) if !matches!(v, Value::Null) => {
                self.walk(field, inner, v, refers_to);
            }
            (FieldType::List(inner), Value::List(vs)) => {
                for v in vs {
                    self.walk(field, inner, v, refers_to);
                }
            }
            (FieldType::Struct(fields), Value::Struct(map)) => {
                self.walk_fields(fields, map);
            }
            (FieldType::Enum(variants), Value::Enum { variant, fields }) => {
                if let Some(decl) = variants.iter().find(|d| &d.name == variant) {
                    self.walk_fields(&decl.fields, fields);
                }
            }
            _ => {}
        }
    }

    fn walk_fields(&mut self, decls: &[Field], values: &std::collections::BTreeMap<String, Value>) {
        for f in decls {
            if let Some(v) = values.get(&f.name) {
                self.walk(&f.name, &f.ty, v, f.refers_to.as_deref());
            }
        }
    }
}

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

    fn field(name: &str, ty: FieldType) -> Field {
        Field {
            name: name.into(),
            doc: String::new(),
            ty,
            role: None,
            refers_to: None,
        }
    }

    fn unit(name: &str) -> Variant {
        Variant {
            name: name.into(),
            doc: String::new(),
            fields: Vec::new(),
            tone: None,
        }
    }

    /// A todo/charter/self-shaped registry, built by hand: validation is
    /// registry-driven, so the fixture is a registry, not a schema crate.
    fn reg() -> Registry {
        Registry {
            schema_hash: String::new(),
            kinds: vec![
                Kind {
                    name: "todo".into(),
                    doc: String::new(),
                    storage: "facts/todos/{id}.ron".into(),
                    fields: vec![
                        field("id", FieldType::Str),
                        field("title", FieldType::Str),
                        field("status", FieldType::Enum(vec![unit("Open"), unit("Done")])),
                        field("due", FieldType::Option(Box::new(FieldType::Date))),
                        field(
                            "blocked_by",
                            FieldType::Option(Box::new(FieldType::Link {
                                allowed: Some(vec!["todo".into()]),
                            })),
                        ),
                        field(
                            "sources",
                            FieldType::List(Box::new(FieldType::Link { allowed: None })),
                        ),
                        field("notes", FieldType::Markdown),
                    ],
                },
                Kind {
                    name: "charter".into(),
                    doc: String::new(),
                    storage: "facts/charter.ron".into(),
                    fields: vec![
                        field("purpose", FieldType::Str),
                        field("objectives", FieldType::List(Box::new(FieldType::Markdown))),
                        field("notes", FieldType::Markdown),
                    ],
                },
                Kind {
                    name: "self".into(),
                    doc: String::new(),
                    storage: "facts/self.ron".into(),
                    fields: vec![
                        field("name", FieldType::Str),
                        field("role", FieldType::Str),
                        field("notes", FieldType::Markdown),
                    ],
                },
            ],
            queries: vec![],
            roles: vec![],
        }
    }

    const SYSTEMS: &[&str] = &["graph", "sharepoint"];

    fn v(entries: &[(&str, &str)]) -> Vec<Violation> {
        let entries: Vec<(String, String)> = entries
            .iter()
            .map(|(p, t)| (p.to_string(), t.to_string()))
            .collect();
        against_registry(&reg(), &entries, SYSTEMS)
    }

    fn errors(v: &[Violation]) -> Vec<&Violation> {
        v.iter().filter(|x| x.severity == Severity::Error).collect()
    }

    fn warnings(v: &[Violation]) -> Vec<&Violation> {
        v.iter()
            .filter(|x| x.severity == Severity::Warning)
            .collect()
    }

    #[test]
    fn happy_path_is_clean() {
        let out = v(&[
            (
                "facts/todos/declare-source.ron",
                r#"(id: "declare-source", title: "Declare", status: Open)"#,
            ),
            (
                "facts/todos/ship-it.ron",
                r#"(id: "ship-it", title: "Ship", status: Open, due: Some("2026-07-31"),
                    blocked_by: Some("todo:declare-source"),
                    sources: ["graph:email:AAMk=="],
                    notes: "see [[charter]] and [[todo:declare-source]]")"#,
            ),
            ("facts/charter.ron", r#"(purpose: "P", objectives: ["o"])"#),
            ("facts/self.ron", r#"(name: "Tom", role: "CTO")"#),
        ]);
        assert!(out.is_empty(), "{out:?}");
    }

    #[test]
    fn routing_parse_and_placeholder_mismatches_are_errors() {
        let out = v(&[
            ("facts/notes/x.ron", "(id: \"x\")"),
            ("facts/todos/readme.txt", "hi"),
            ("facts/todos/broken.ron", "(id: "),
            ("facts/todos/ship-it.ron", r#"(id: "ship", title: "T")"#),
            (
                "facts/todos/bad-date.ron",
                r#"(id: "bad-date", title: "T", due: Some("someday"))"#,
            ),
            ("tools/elsewhere.txt", "ignored"),
        ]);
        let e = errors(&out);
        assert_eq!(e.len(), 5, "{out:?}");
        assert!(
            e.iter()
                .any(|x| x.message.contains("not a recognised KB path")
                    && x.message.contains("facts/todos/{id}.ron"))
        );
        assert!(
            e.iter().any(
                |x| x.path.contains("broken") && x.message.contains("does not parse as a todo")
            )
        );
        assert!(e.iter().any(|x| {
            x.message
                .contains("id 'ship' does not match filename 'ship-it'")
        }));
        assert!(
            e.iter()
                .any(|x| x.path.contains("bad-date") && x.message.contains("does not parse"))
        );
    }

    #[test]
    fn multi_segment_placeholders_check_each_position() {
        let mut registry = reg();
        registry.kinds.push(Kind {
            name: "checkin".into(),
            doc: String::new(),
            storage: "facts/checkins/{person}/{date}.ron".into(),
            fields: vec![
                field("person", FieldType::Str),
                field("date", FieldType::Date),
            ],
        });
        let entries = vec![(
            "facts/checkins/jane-doe/2026-07-03.ron".to_string(),
            r#"(person: "bob-ray", date: "2026-07-04")"#.to_string(),
        )];
        let out = against_registry(&registry, &entries, SYSTEMS);
        let e = errors(&out);
        assert!(e.iter().any(|x| {
            x.message
                .contains("person 'bob-ray' does not match directory 'jane-doe'")
        }));
        assert!(e.iter().any(|x| {
            x.message
                .contains("date '2026-07-04' does not match filename '2026-07-03'")
        }));
    }

    #[test]
    fn link_policy_rejects_disallowed_kinds() {
        let out = v(&[
            (
                "facts/todos/b.ron",
                r#"(id: "b", title: "B", blocked_by: Some("charter"))"#,
            ),
            ("facts/charter.ron", r#"(purpose: "P")"#),
        ]);
        let e = errors(&out);
        assert_eq!(e.len(), 1, "{out:?}");
        assert!(e[0].message.contains("blocked_by") && e[0].message.contains("kind 'charter'"));
    }

    #[test]
    fn dangling_and_unrecognized_links_warn_externals_pass() {
        let out = v(&[(
            "facts/todos/b.ron",
            r#"(id: "b", title: "B", blocked_by: Some("todo:ghost"),
                sources: ["jira:EV-12", "graph:email:fine=="])"#,
        )]);
        assert!(errors(&out).is_empty(), "{out:?}");
        let w = warnings(&out);
        assert_eq!(w.len(), 2, "{w:?}");
        assert!(
            w.iter()
                .any(|x| x.message.contains("does not resolve to a known todo"))
        );
        assert!(
            w.iter()
                .any(|x| x.message.contains("unrecognized link 'jira:EV-12'"))
        );
    }

    #[test]
    fn singletons_resolve_iff_present_and_take_no_id() {
        let todo = (
            "facts/todos/b.ron",
            r#"(id: "b", title: "B", notes: "per [[charter]] and [[charter:2026]]")"#,
        );
        let out = v(&[todo, ("facts/charter.ron", r#"(purpose: "P")"#)]);
        assert!(errors(&out).is_empty());
        let w = warnings(&out);
        assert_eq!(w.len(), 1, "{w:?}");
        assert!(
            w[0].message
                .contains("singleton kind 'charter' takes no id")
        );

        let out = v(&[todo]);
        assert!(
            warnings(&out)
                .iter()
                .any(|x| x.message.contains("no charter record present"))
        );
    }

    #[test]
    fn inline_links_are_scanned_in_every_markdown_store() {
        let out = v(&[
            (
                "facts/todos/b.ron",
                r#"(id: "b", title: "B", notes: "see [[todo:ghost1]]; [[not a link]] is prose")"#,
            ),
            (
                "facts/charter.ron",
                r#"(purpose: "P", objectives: ["see [[todo:ghost2]]"], notes: "see [[todo:ghost3]]")"#,
            ),
            (
                "facts/self.ron",
                r#"(name: "T", role: "R", notes: "see [[todo:ghost4]]")"#,
            ),
        ]);
        assert!(errors(&out).is_empty());
        let inline: Vec<_> = warnings(&out)
            .into_iter()
            .filter(|x| x.message.starts_with("inline"))
            .collect();
        assert_eq!(inline.len(), 4, "{out:?}");
    }

    #[test]
    fn refers_to_slugs_warn_when_unknown() {
        let mut registry = reg();
        let mut person_field = field("person", FieldType::Str);
        person_field.refers_to = Some("todo".into());
        registry.kinds.push(Kind {
            name: "checkin".into(),
            doc: String::new(),
            storage: "facts/checkins/{person}/{date}.ron".into(),
            fields: vec![person_field, field("date", FieldType::Date)],
        });
        let entries = vec![(
            "facts/checkins/ghost/2026-07-01.ron".to_string(),
            r#"(person: "ghost", date: "2026-07-01")"#.to_string(),
        )];
        let out = against_registry(&registry, &entries, SYSTEMS);
        assert!(errors(&out).is_empty(), "{out:?}");
        assert!(
            warnings(&out)
                .iter()
                .any(|x| x.message.contains("person 'ghost' is not a known todo"))
        );
    }

    /// SOL finding 18's generic descendant: a Link inside an enum VARIANT
    /// payload gets the same policy and resolution as a top-level field.
    #[test]
    fn enum_payload_links_are_checked() {
        let mut registry = reg();
        registry.kinds.push(Kind {
            name: "probe".into(),
            doc: String::new(),
            storage: "facts/probes/{id}.ron".into(),
            fields: vec![
                field("id", FieldType::Str),
                Field {
                    name: "client".into(),
                    doc: String::new(),
                    ty: FieldType::Enum(vec![
                        unit("Unknown"),
                        Variant {
                            name: "Known".into(),
                            doc: String::new(),
                            fields: vec![field(
                                "todo",
                                FieldType::Link {
                                    allowed: Some(vec!["todo".into()]),
                                },
                            )],
                            tone: None,
                        },
                    ]),
                    role: None,
                    refers_to: None,
                },
            ],
        });
        let entries = vec![(
            "facts/probes/p1.ron".to_string(),
            r#"(id: "p1", client: Known(todo: "charter"))"#.to_string(),
        )];
        let out = against_registry(&registry, &entries, SYSTEMS);
        assert!(
            errors(&out)
                .iter()
                .any(|x| x.message.contains("todo") && x.message.contains("kind 'charter'")),
            "{out:?}"
        );
    }
}