BREP_app 0.2.0

//! UPDATE COMPONENTS — the assemblies build-spec §8.6 flow: compare each
//! parts-library entry's `sourceSignature` against the ModelStore's CURRENT
//! content for its `sourceKey` (with [`document_signature`], the ONE signature
//! fn), badge the outdated count on the Assembly Constraints header and the
//! per-node rows of the structure tree, and refresh every outdated entry
//! through the ESTABLISHED document-transport lane
//! ([`refresh_library_entry`]): rewrite the embedded `document` + a fresh
//! signature + a BLANKED snapshot per entry, then ONE reload — the kernel
//! self-heals every instance from the refreshed documents, re-solves, and the
//! main-side sync captures the healed snapshots back into the document.
//!
//! # Staleness (recompute on a cheap trigger, never per frame)
//!
//! The comparison reads the store once per entry — too hot to recompute on
//! every panel draw. [`UpdateComponents::ensure_current`] caches the result
//! keyed on `(EngineState::applied_generation, FileDialog::save_generation)`:
//!
//! * an applied history run bumps the first half (covers opening an assembly,
//!   inserting components, edit-in-place Finish, constraint solves);
//! * a successful store save bumps the second (covers Open Part → edit →
//!   save → return to the assembly: the badge lights without a restart).
//!
//! Entries with an EMPTY `sourceKey` (embedded-only parts) are skipped;
//! entries whose key has no store document are NOTED (surfaced in the header
//! hover + a run-time notice) but never counted — they cannot be refreshed.
//!
//! The comparison only means "outdated" because every writer keeps the entry's
//! `sourceSignature` equal to what the FILE holds: the insert lane hashes the
//! file it read, [`UpdateComponents::run`] hashes the file it just pulled in,
//! and edit-in-place Finish SAVES the edited part back to its `sourceKey`
//! before stamping the signature (`panels::assembly_edit`'s write-through
//! lane). Without that last one an in-context edit read as outdated against a
//! file it was newer than — the badge meaning the opposite of what happened.

use crate::panels::assembly_edit::{document_signature, refresh_library_entry};
use crate::store::ModelStore;
use brep_render::engine_state::EngineState;
use serde_json::Value;

/// The shell-owned outdated-parts checker + batch refresher. One instance on
/// the app; the constraints panel reads the count (and runs the refresh), the
/// structure tree reads per-part flags.
#[derive(Default)]
pub struct UpdateComponents {
    /// Parts-library entry names whose store content no longer matches their
    /// `sourceSignature` — the badge count.
    outdated: Vec<String>,
    /// Entry names with a `sourceKey` but NO store document under it (noted,
    /// never counted — nothing to refresh from).
    missing: Vec<String>,
    /// The `(applied_generation, save_generation)` key the cache was computed
    /// against; `None` forces a recompute on the next ensure.
    checked: Option<(u64, u64)>,
}

impl UpdateComponents {
    pub fn new() -> Self {
        Self::default()
    }

    /// Recompute the outdated/missing sets when the staleness key moved (or
    /// after [`Self::invalidate`]); otherwise a cheap compare. The shell calls
    /// this once per frame BEFORE the assembly panels draw.
    pub fn ensure_current(
        &mut self,
        state: &mut EngineState,
        model_store: &dyn ModelStore,
        save_generation: u64,
    ) {
        let key = (state.applied_generation(), save_generation);
        if self.checked == Some(key) {
            return;
        }
        let (outdated, missing) = compute(state, model_store);
        self.outdated = outdated;
        self.missing = missing;
        self.checked = Some(key);
    }

    /// Drop the cache so the next [`Self::ensure_current`] recomputes even on
    /// an unmoved key (after a run, or an external store change).
    pub fn invalidate(&mut self) {
        self.checked = None;
    }

    /// The outdated-entry count — the constraints-header badge number.
    pub fn outdated_count(&self) -> usize {
        self.outdated.len()
    }

    /// Whether `part_name`'s library entry is outdated — the structure tree's
    /// per-node badge (every instance of the part lights).
    pub fn is_outdated(&self, part_name: &str) -> bool {
        self.outdated.iter().any(|part| part == part_name)
    }

    /// Entry names noted as source-less (header hover text).
    pub fn missing(&self) -> &[String] {
        &self.missing
    }

    /// RUN the update (the header button): recompute against the LIVE document
    /// (never a stale cache), rewrite every outdated entry from its store
    /// content through [`refresh_library_entry`], then reload ONCE — the
    /// kernel self-heals every instance + re-solves, and the main-side sync
    /// captures healed snapshots back. Per-entry failures (missing store key,
    /// unreadable content) toast and SKIP — the batch never aborts. Returns
    /// the number of entries refreshed.
    pub fn run(
        &mut self,
        state: &mut EngineState,
        model_store: &dyn ModelStore,
    ) -> Result<usize, String> {
        let (outdated, missing) = compute(state, model_store);
        if !missing.is_empty() {
            state.push_notice(format!(
                "Update components: no source document for {} — skipped",
                missing.join(", ")
            ));
        }
        if outdated.is_empty() {
            self.invalidate();
            return Ok(0);
        }
        let mut document: Value = serde_json::from_str(&state.history_request_json())
            .map_err(|error| format!("assembly document unreadable: {error}"))?;
        let mut refreshed = 0usize;
        for part_name in &outdated {
            let source_key = document["partsLibrary"][part_name]["sourceKey"]
                .as_str()
                .unwrap_or_default()
                .to_string();
            let Some(contents) = model_store.read(&source_key) else {
                state.push_notice(format!(
                    "Update components: '{part_name}' source '{source_key}' missing — skipped"
                ));
                continue;
            };
            match refresh_library_entry(&mut document, part_name, &contents) {
                Ok(()) => refreshed += 1,
                Err(error) => state.push_notice(format!(
                    "Update components: '{part_name}': {error} — skipped"
                )),
            }
        }
        if refreshed > 0 {
            // The ONE reload for the whole batch (no zoom — the camera stays).
            state
                .set_history_json(&document.to_string())
                .map_err(|error| format!("assembly reload failed: {error}"))?;
            state.push_notice(format!(
                "Updated {refreshed} part(s) from source — every instance rebuilt"
            ));
        }
        self.invalidate();
        Ok(refreshed)
    }
}

/// The signature comparison over the LIVE document's `partsLibrary` block →
/// `(outdated, missing)` entry-name sets. Componentless documents short-circuit
/// to empty (zero cost for modeling files).
fn compute(state: &mut EngineState, model_store: &dyn ModelStore) -> (Vec<String>, Vec<String>) {
    let mut outdated = Vec::new();
    let mut missing = Vec::new();
    if !state.history_has_assembly() {
        return (outdated, missing);
    }
    // The document's partsLibrary block mirrors the kernel store post-sync
    // (heals + GC included) — make sure that fold ran for this generation.
    state.ensure_assembly_synced();
    let Ok(document) = serde_json::from_str::<Value>(&state.history_request_json()) else {
        return (outdated, missing);
    };
    let Some(library) = document.get("partsLibrary").and_then(Value::as_object) else {
        return (outdated, missing);
    };
    for (part_name, entry) in library {
        let Some(source_key) = entry
            .get("sourceKey")
            .and_then(Value::as_str)
            .filter(|key| !key.is_empty())
        else {
            continue; // embedded-only part: no source to compare against
        };
        match model_store.read(source_key) {
            None => missing.push(part_name.clone()),
            Some(contents) => {
                let signature = entry
                    .get("sourceSignature")
                    .and_then(Value::as_str)
                    .unwrap_or_default();
                if document_signature(&contents) != signature {
                    outdated.push(part_name.clone());
                }
            }
        }
    }
    (outdated, missing)
}

#[cfg(all(test, not(target_arch = "wasm32")))]
pub(crate) mod tests {
    use super::*;
    use crate::store::MemModelStore;
    use brep_render::engine_state::ComponentInsert;

    /// A one-cube part document with a parameterized width (the edit under
    /// test), matching the shared assembly fixtures.
    pub(crate) fn part_document(size_x: f64) -> String {
        serde_json::json!({
            "expressions": "",
            "configurator": {},
            "features": [{
                "type": "P.CU",
                "inputParams": {
                    "id": "Part",
                    "sizeX": size_x, "sizeY": 3.0, "sizeZ": 4.0,
                    "transform": {
                        "position": [0.0, 0.0, 0.0],
                        "rotationEuler": [0.0, 0.0, 0.0],
                        "scale": [1.0, 1.0, 1.0]
                    },
                    "boolean": { "targets": [], "operation": "NONE" }
                },
                "persistentData": {}
            }]
        })
        .to_string()
    }

    /// A two-instance assembly inserted THROUGH the real flow, with its part
    /// content resident in an in-memory store under the entry's `sourceKey`
    /// and the signature written by the ONE signature fn (as the insert lane
    /// does) — the fresh-insert-compares-up-to-date invariant's ground truth.
    pub(crate) fn assembly_with_store() -> (EngineState, MemModelStore) {
        brep_render::brep_kernel::clear_history_cache();
        let store = MemModelStore::new();
        let content = part_document(10.0);
        store.put("widget", &content);
        let mut state = EngineState::new();
        state
            .insert_component(ComponentInsert::New {
                name: "widget",
                source_key: "widget",
                source_signature: &document_signature(&content),
                document_json: &content,
            })
            .expect("insert 1");
        state
            .insert_component(ComponentInsert::Existing { part_name: "widget" })
            .expect("insert 2");
        (state, store)
    }

    fn size_x_of(state: &EngineState, solid: &str) -> f64 {
        let bbox = &state.scene.solid(solid).expect(solid).bbox;
        bbox.max[0] - bbox.min[0]
    }

    /// DETECTION: fresh insert → 0; changed store content → counted; a
    /// missing store key → not counted but noted. The save-generation half of
    /// the staleness key drives each recheck (the after-save trigger).
    #[test]
    fn outdated_detection_counts_changed_and_notes_missing() {
        let (mut state, store) = assembly_with_store();
        let mut updates = UpdateComponents::new();

        updates.ensure_current(&mut state, &store, 0);
        assert_eq!(updates.outdated_count(), 0, "fresh insert compares up-to-date");
        assert!(updates.missing().is_empty());

        // The part's source changes (edited + saved elsewhere) → counted, and
        // BOTH instances of the one entry light through is_outdated.
        store.put("widget", &part_document(14.0));
        updates.ensure_current(&mut state, &store, 1);
        assert_eq!(updates.outdated_count(), 1);
        assert!(updates.is_outdated("widget"));
        assert!(!updates.is_outdated("other"));

        // A key-order-only variant of the ORIGINAL content is NOT outdated
        // (the signature walks parsed JSON with sorted keys, not raw text).
        let reordered = {
            let value: Value = serde_json::from_str(&part_document(10.0)).unwrap();
            serde_json::to_string_pretty(&value).unwrap()
        };
        store.put("widget", &reordered);
        updates.ensure_current(&mut state, &store, 2);
        assert_eq!(updates.outdated_count(), 0, "formatting-only resave is not outdated");

        // The store document vanishes: noted, never counted.
        store.remove("widget").unwrap();
        updates.ensure_current(&mut state, &store, 3);
        assert_eq!(updates.outdated_count(), 0);
        assert_eq!(updates.missing(), ["widget".to_string()]);
    }

    /// STALENESS: a stable `(applied, save)` key never re-reads the store; a
    /// moved save-generation (or an applied run) recomputes.
    #[test]
    fn ensure_current_caches_per_generation_key() {
        let (mut state, store) = assembly_with_store();
        let mut updates = UpdateComponents::new();

        updates.ensure_current(&mut state, &store, 0);
        let reads = store.reads();
        assert!(reads > 0, "first ensure reads the store");
        updates.ensure_current(&mut state, &store, 0);
        assert_eq!(store.reads(), reads, "stable key: no re-read per frame");
        updates.ensure_current(&mut state, &store, 1);
        assert!(store.reads() > reads, "a save bump recomputes");
    }

    /// THE REFRESH ROUND-TRIP: run() rewrites the outdated entry from the
    /// store (document + signature), the reload rebuilds EVERY instance with
    /// the edit, the main-side sync captures a restorable snapshot back into
    /// the document (non-blank), and the badge recomputes to 0.
    #[test]
    fn run_refreshes_entries_instances_and_snapshot() {
        let (mut state, store) = assembly_with_store();
        let new_content = part_document(14.0);
        store.put("widget", &new_content);
        let mut updates = UpdateComponents::new();
        updates.ensure_current(&mut state, &store, 1);
        assert_eq!(updates.outdated_count(), 1);

        let refreshed = updates.run(&mut state, &store).expect("run ok");
        assert_eq!(refreshed, 1);

        // Entry document + signature updated; snapshot captured back healed.
        let document: Value = serde_json::from_str(&state.history_request_json()).unwrap();
        let entry = &document["partsLibrary"]["widget"];
        assert_eq!(entry["document"]["features"][0]["inputParams"]["sizeX"], 14.0);
        assert_eq!(entry["sourceSignature"], document_signature(&new_content));
        let snapshot = entry["snapshot"].as_str().unwrap_or_default();
        assert!(!snapshot.is_empty(), "the sync captured the healed snapshot");
        assert!(brep_render::brep_kernel::restore_solids(snapshot).is_ok());

        // Both instances rebuilt with the edit.
        assert!((size_x_of(&state, "ACOMP1:Part") - 14.0).abs() < 1e-6);
        assert!((size_x_of(&state, "ACOMP2:Part") - 14.0).abs() < 1e-6);

        // The run invalidated the cache; a recheck lands on 0.
        updates.ensure_current(&mut state, &store, 1);
        assert_eq!(updates.outdated_count(), 0, "everything up-to-date after the run");

        let notices = state.take_notices();
        assert!(
            notices.iter().any(|n| n.contains("Updated 1 part")),
            "{notices:?}"
        );
    }

    /// FAILURE TOLERANCE: an unreadable source toasts + skips while the good
    /// entry refreshes; a vanished source key is noted + skipped — the batch
    /// never aborts and never damages the skipped entry.
    #[test]
    fn per_entry_failures_toast_and_skip() {
        brep_render::brep_kernel::clear_history_cache();
        let store = MemModelStore::new();
        let widget = part_document(10.0);
        let gadget = part_document(9.0);
        store.put("widget", &widget);
        store.put("gadget", &gadget);
        let mut state = EngineState::new();
        state
            .insert_component(ComponentInsert::New {
                name: "widget",
                source_key: "widget",
                source_signature: &document_signature(&widget),
                document_json: &widget,
            })
            .unwrap();
        state
            .insert_component(ComponentInsert::New {
                name: "gadget",
                source_key: "gadget",
                source_signature: &document_signature(&gadget),
                document_json: &gadget,
            })
            .unwrap();
        let mut updates = UpdateComponents::new();

        // widget's source changes VALIDLY; gadget's becomes unreadable.
        store.put("widget", &part_document(14.0));
        store.put("gadget", "definitely not json");
        let refreshed = updates.run(&mut state, &store).expect("batch survives");
        assert_eq!(refreshed, 1, "the good entry refreshed, the bad one skipped");
        let notices = state.take_notices();
        assert!(
            notices
                .iter()
                .any(|n| n.contains("gadget") && n.contains("unreadable")),
            "{notices:?}"
        );
        let document: Value = serde_json::from_str(&state.history_request_json()).unwrap();
        assert_eq!(
            document["partsLibrary"]["widget"]["document"]["features"][0]["inputParams"]["sizeX"],
            14.0
        );
        assert_eq!(
            document["partsLibrary"]["gadget"]["document"]["features"][0]["inputParams"]["sizeX"],
            9.0,
            "the skipped entry keeps its old content"
        );

        // Second wave: gadget's source key vanishes entirely (missing lane).
        store.put("widget", &part_document(16.0));
        store.remove("gadget").unwrap();
        let refreshed = updates.run(&mut state, &store).expect("batch survives");
        assert_eq!(refreshed, 1);
        let notices = state.take_notices();
        assert!(
            notices
                .iter()
                .any(|n| n.contains("no source document") && n.contains("gadget")),
            "{notices:?}"
        );
    }
}