lean-ctx-server 3.12.2

// SPDX-License-Identifier: Apache-2.0
use chrono::Utc;

#[cfg(feature = "embeddings")]
use lean_ctx::core::embeddings::EmbeddingEngine;

use lean_ctx::core::consolidation_engine::ConsolidateOptions;
use lean_ctx::core::knowledge::ProjectKnowledge;
use lean_ctx::core::memory_policy::MemoryPolicy;
use lean_ctx::core::session::SessionState;
mod changes;
pub(crate) use changes::session_change_count;
pub(crate) mod embeddings;
pub(crate) use embeddings::*;
mod linked;
mod remember;
pub use remember::*;
mod restore;
pub use restore::{DEFAULT_RESTORE_LIMIT, RestoreOptions, format_restore_report, run_restore};
mod search;
pub(crate) use search::*;

mod consolidate;
pub use consolidate::*;
#[cfg(test)]
mod engine_tests;
#[cfg(test)]
mod hive_guard_tests;
#[cfg(test)]
mod tests;

/// Dispatches knowledge base actions (remember, recall, pattern, timeline, etc.).
#[allow(clippy::too_many_arguments)]
pub fn handle(
    project_root: &str,
    action: &str,
    category: Option<&str>,
    key: Option<&str>,
    value: Option<&str>,
    query: Option<&str>,
    session_id: &str,
    pattern_type: Option<&str>,
    examples: Option<Vec<String>>,
    confidence: Option<f32>,
    mode: Option<&str>,
    as_of: Option<&str>,
) -> String {
    match handle_outcome(
        project_root,
        action,
        category,
        key,
        value,
        query,
        session_id,
        pattern_type,
        examples,
        confidence,
        mode,
        as_of,
    ) {
        Ok(text) | Err(text) => text,
    }
}

/// [`handle`] with a typed outcome: `Ok` is the reply, `Err` is the text of a
/// failed call — the same text [`handle`] answers, after the same gates.
///
/// Typed as failures are the refusals every action shares (knowledge
/// protection unavailable, output withheld by policy, recovered text not
/// admitted) and every failure of `recall`, `timeline` and `search` — the
/// actions that declare every source
/// (`CtxKnowledgeTool::publishes_every_source`), whose error text must never
/// be recorded as a delivery of the sources captured before the failure. The
/// other actions still answer their own failures as reply text.
#[allow(clippy::too_many_arguments)]
pub fn handle_outcome(
    project_root: &str,
    action: &str,
    category: Option<&str>,
    key: Option<&str>,
    value: Option<&str>,
    query: Option<&str>,
    session_id: &str,
    pattern_type: Option<&str>,
    examples: Option<Vec<String>>,
    confidence: Option<f32>,
    mode: Option<&str>,
    as_of: Option<&str>,
) -> Result<String, String> {
    if let Err(error) = lean_ctx::core::knowledge::protection::current(project_root) {
        return Err(format!("Error: {error}"));
    }
    lean_ctx::core::policy::runtime::REQUEST_PROJECT.sync_scope(
        std::cell::RefCell::new(Some(std::path::PathBuf::from(project_root))),
        || {
    let declared = match action {
        "recall" => Some(handle_recall(project_root, category, query, session_id, mode, as_of)),
        "timeline" => Some(handle_timeline(project_root, category)),
        "search" => Some(handle_search(query, session_id)),
        _ => None,
    };
    let failed = matches!(declared, Some(Err(_)));
    let result = match declared {
        Some(Ok(text) | Err(text)) => text,
        None => match action {
        "policy" => handle_policy(value),
        "remember" => handle_remember(project_root, category, key, value, session_id, confidence),
        "pattern" => handle_pattern(project_root, pattern_type, value, examples, session_id),
        "feedback" => handle_feedback(project_root, category, key, value, session_id),
        "relate" => crate::tools::ctx_knowledge_relations::handle_relate(
            project_root,
            category,
            key,
            value,
            query,
            session_id,
        ),
        "unrelate" => crate::tools::ctx_knowledge_relations::handle_unrelate(
            project_root,
            category,
            key,
            value,
            query,
        ),
        "relations" => crate::tools::ctx_knowledge_relations::handle_relations(
            project_root,
            category,
            key,
            value,
            query,
        ),
        "relations_diagram" => crate::tools::ctx_knowledge_relations::handle_relations_diagram(
            project_root,
            category,
            key,
            value,
            query,
        ),
        "status" => handle_status(project_root),
        "changes" => changes::handle_changes(project_root, query, session_id),
        "repin" => changes::handle_repin(project_root, category, key),
        "coverage" => changes::handle_coverage(project_root),
        "health" => handle_health(project_root),
        "lifecycle_report" => handle_lifecycle_report(project_root),
        "remove" => handle_remove(project_root, category, key),
        "export" => handle_export(project_root),
        "consolidate" => handle_consolidate(project_root),
        "consolidate_preview" => handle_consolidate_preview(project_root),
        "restore" => handle_restore(project_root, category, query, None),
        "rooms" => handle_rooms(project_root),
        "wakeup" => handle_wakeup(project_root),
        "embeddings_status" => handle_embeddings_status(project_root),
        "embeddings_reset" => handle_embeddings_reset(project_root),
        "embeddings_reindex" => handle_embeddings_reindex(project_root),
        "judge" => handle_judge(project_root, category, key, value, query),
        // Deprecated no-op (rust/data/DEPRECATIONS.toml): accepted until removal.
        "cognition_loop" => "ctx_knowledge action=cognition_loop is retired and has no effect: scheduled consolidation already runs the memory lifecycle (decay, merge, archival). Use action=consolidate to run it now.".to_string(),
        "bridge_publish" => handle_bridge_publish(project_root, session_id),
        "bridge_pull" => handle_bridge_pull(project_root, session_id),
        "bridge_status" => handle_bridge_status(project_root),
        _ => format!(
            "Unknown action: {action}. Use: policy, remember, recall, pattern, feedback, judge, relate, unrelate, relations, relations_diagram, status, health, lifecycle_report, remove, export, consolidate, consolidate_preview, restore, timeline, rooms, search, wakeup, embeddings_status, embeddings_reset, embeddings_reindex, bridge_publish, bridge_pull, bridge_status"
        ),
        },
    };
    let Ok(result) = lean_ctx::core::policy::content::protect_active(&result) else {
        return Err("Error: knowledge output withheld by current policy".to_string());
    };
    // Stored knowledge is recovered text: every view of it passes the context
    // gateway under the current policy, including facts written before the
    // store admitted its input (G5). A failure text passes the same gates.
    match lean_ctx::core::context_admission::recovery::admit_recovered(&result, "knowledge") {
        Ok(text) if failed => Err(text),
        Ok(text) if action == "wakeup" => Ok(wakeup_delta(value, text)),
        Ok(text) => Ok(text),
        Err(error) => Err(format!("Error: {error}")),
    }
        },
    )
}

fn handle_policy(value: Option<&str>) -> String {
    let sub = value.unwrap_or("show").trim().to_lowercase();
    let profile = lean_ctx::core::profiles::active_profile_name();

    match sub.as_str() {
        "show" => {
            let policy = match load_policy_or_error() {
                Ok(p) => p,
                Err(e) => return e,
            };

            let cfg_path = lean_ctx::core::config::Config::path().map_or_else(
                || "~/.lean-ctx/config.toml".to_string(),
                |p| p.display().to_string(),
            );

            format!(
                "Knowledge policy (effective, profile={profile}):\n\
                 - memory.knowledge facts: no limit (max_facts is ignored)\n\
                 - memory.knowledge.contradiction_threshold={}\n\
                 - memory.knowledge.recall_facts_limit={}\n\
                 - memory.knowledge.rooms_limit={}\n\
                 - memory.knowledge.timeline_limit={}\n\
                 - memory.knowledge.relations_limit={}\n\
                 - memory.lifecycle.decay_rate={}\n\
                 - memory.lifecycle.stale_days={}\n\
                 \nConfig: {cfg_path}",
                policy.knowledge.contradiction_threshold,
                policy.knowledge.recall_facts_limit,
                policy.knowledge.rooms_limit,
                policy.knowledge.timeline_limit,
                policy.knowledge.relations_limit,
                policy.lifecycle.decay_rate,
                policy.lifecycle.stale_days
            )
        }
        "validate" => match load_policy_or_error() {
            Ok(_) => format!("OK: memory policy valid (profile={profile})"),
            Err(e) => e,
        },
        _ => "Error: policy value must be show|validate".to_string(),
    }
}

fn handle_feedback(
    project_root: &str,
    category: Option<&str>,
    key: Option<&str>,
    value: Option<&str>,
    session_id: &str,
) -> String {
    let Some(cat) = category else {
        return "Error: category is required for feedback".to_string();
    };
    let Some(k) = key else {
        return "Error: key is required for feedback".to_string();
    };
    let dir = value.unwrap_or("up").trim().to_lowercase();
    let is_up = matches!(dir.as_str(), "up" | "+1" | "+" | "true" | "1");
    let is_down = matches!(dir.as_str(), "down" | "-1" | "-" | "false" | "0");
    if !is_up && !is_down {
        return "Error: feedback value must be up|down (+1|-1)".to_string();
    }

    // Read-modify-write under the cross-process lock (#326/#594) so concurrent
    // CLI/daemon/MCP feedback never clobbers each other.
    let outcome = ProjectKnowledge::mutate_locked(project_root, |knowledge| {
        let Some(f) = knowledge
            .facts
            .iter_mut()
            .find(|f| f.is_current() && f.category == cat && f.key == k)
        else {
            return Err(format!("No current fact found: [{cat}] {k}"));
        };

        if is_up {
            f.feedback_up = f.feedback_up.saturating_add(1);
        } else {
            f.feedback_down = f.feedback_down.saturating_add(1);
        }
        f.last_feedback = Some(Utc::now());
        Ok((
            f.quality_score(),
            f.feedback_up,
            f.feedback_down,
            f.confidence,
        ))
    });

    let (quality, up, down, conf) = match outcome {
        Ok((_, Ok(vals))) => vals,
        Ok((_, Err(msg))) => return msg,
        Err(e) => return format!("Error: feedback was not saved: {e}"),
    };

    lean_ctx::core::events::emit(lean_ctx::core::events::EventKind::KnowledgeUpdate {
        category: cat.to_string(),
        key: k.to_string(),
        action: if is_up {
            "feedback_up"
        } else {
            "feedback_down"
        }
        .to_string(),
    });

    format!(
        "Feedback recorded ({dir}) for [{cat}] {k} (up={up}, down={down}, quality={quality:.2}, confidence={conf:.2}, session={session_id})"
    )
}

pub(crate) fn handle_judge(
    project_root: &str,
    category: Option<&str>,
    key: Option<&str>,
    value: Option<&str>,
    query: Option<&str>,
) -> String {
    let source = match (category, key) {
        (Some(cat), Some(k)) => format!("{cat}/{k}"),
        _ => {
            if let Some(k) = key.or(category) {
                if k.contains('/') {
                    k.to_string()
                } else {
                    return "Error: judge requires key as 'category/key' (source fact)".to_string();
                }
            } else {
                return "Error: judge requires category+key (source fact) and value (target 'category/key')"
                    .to_string();
            }
        }
    };

    let Some(target) = value else {
        return "Error: judge requires value as target 'category/key'".to_string();
    };
    let target = target.trim().to_string();
    if !target.contains('/') {
        return "Error: target must be 'category/key' format".to_string();
    }

    let verdict = query.unwrap_or("compatible").trim().to_lowercase();
    if !matches!(
        verdict.as_str(),
        "supersedes" | "compatible" | "unrelated" | "contradicts"
    ) {
        return format!(
            "Error: verdict must be supersedes|compatible|unrelated|contradicts, got '{verdict}'"
        );
    }

    // Read-modify-write under the cross-process lock (#326/#594).
    let result = ProjectKnowledge::mutate_locked(project_root, |knowledge| {
        let src = current_fact_index(knowledge, &source)?;
        let tgt = current_fact_index(knowledge, &target)?;
        if src == tgt {
            return Err("Error: a fact is not judged against itself".to_string());
        }
        let now = Utc::now();

        if verdict == "supersedes" {
            let tf = &mut knowledge.facts[tgt];
            tf.valid_until = Some(now);
            tf.valid_from = tf.valid_from.or(Some(tf.created_at));
            // The survivor of a judged contradiction is no longer contradicted.
            let sf = &mut knowledge.facts[src];
            if sf.review.as_ref().is_some_and(|r| {
                r.reason == lean_ctx::core::knowledge::FactReviewReason::Contradiction
            }) {
                sf.clear_review();
            }
        }
        // J2: both stay current and both are marked until one supersedes the
        // other. A Hive fact's state reaches Hive with the next sync
        // (C0 1.9 section 3), which opens a task when nobody resolves it.
        if verdict == "contradicts" {
            use lean_ctx::core::knowledge::{FactReviewReason, FactReviewState};
            for i in [src, tgt] {
                knowledge.facts[i].mark_review(
                    FactReviewState::Contradicted,
                    FactReviewReason::Contradiction,
                    now,
                );
            }
        }

        knowledge
            .judged_pairs
            .push(lean_ctx::core::knowledge::JudgedPair {
                key_a: source.clone(),
                key_b: target.clone(),
                verdict: verdict.clone(),
                judged_at: now,
            });
        Ok(())
    });

    match result {
        Ok((_, Ok(()))) => {}
        Ok((_, Err(msg))) => return msg,
        Err(e) => return format!("Error: judge save failed: {e}"),
    }

    let action_desc = match verdict.as_str() {
        "supersedes" => format!("{source} supersedes {target} (target archived)"),
        "compatible" => format!("{source} ↔ {target} (compatible, suppressed from future similar)"),
        "unrelated" => format!("{source} ≠ {target} (unrelated, suppressed from future similar)"),
        "contradicts" => format!(
            "{source} ⟂ {target} (contradicts: both marked contradicted until one supersedes the other)"
        ),
        _ => unreachable!(),
    };

    format!("Judged: {action_desc}")
}

/// The current fact named `spec` (`category/key`; categories and keys may
/// contain `/`, so the whole name is matched).
fn current_fact_index(
    knowledge: &lean_ctx::core::knowledge::ProjectKnowledge,
    spec: &str,
) -> Result<usize, String> {
    let mut found = knowledge.facts.iter().enumerate().filter(|(_, f)| {
        f.is_current()
            && spec.len() == f.category.len() + 1 + f.key.len()
            && spec.starts_with(f.category.as_str())
            && spec[f.category.len()..].starts_with('/')
            && spec.ends_with(f.key.as_str())
    });
    match (found.next(), found.next()) {
        (Some((i, _)), None) => Ok(i),
        (Some(_), Some(_)) => Err(format!("Error: '{spec}' names more than one current fact")),
        (None, _) => Err(format!("Error: no current fact found for '{spec}'")),
    }
}

fn handle_pattern(
    project_root: &str,
    pattern_type: Option<&str>,
    value: Option<&str>,
    examples: Option<Vec<String>>,
    session_id: &str,
) -> String {
    let Some(pt) = pattern_type else {
        return "Error: pattern_type is required".to_string();
    };
    let Some(desc) = value else {
        return "Error: value (description) is required for pattern".to_string();
    };
    let exs = examples.unwrap_or_default();
    let policy = match lean_ctx::core::config::Config::load().memory_policy_effective() {
        Ok(p) => p,
        Err(e) => {
            let path = lean_ctx::core::config::Config::path().map_or_else(
                || "~/.lean-ctx/config.toml".to_string(),
                |p| p.display().to_string(),
            );
            return format!("Error: invalid memory policy: {e}\nFix: edit {path}");
        }
    };
    // Read-modify-write under the cross-process lock (#326/#594).
    match ProjectKnowledge::mutate_locked(project_root, |knowledge| {
        knowledge.add_pattern(pt, desc, exs, session_id, &policy);
    }) {
        Ok(_) => format!("Pattern [{pt}] added: {desc}"),
        Err(e) => format!("Pattern add failed: {e}"),
    }
}

fn handle_status(project_root: &str) -> String {
    let Some(knowledge) = ProjectKnowledge::load(project_root) else {
        return "No knowledge stored for this project yet. Use ctx_knowledge(action=\"remember\") to start.".to_string();
    };

    let current_facts = knowledge.facts.iter().filter(|f| f.is_current()).count();
    let archived_facts = knowledge.facts.len() - current_facts;

    let mut out = format!(
        "Project Knowledge: {} active facts ({} archived), {} patterns, {} history entries\n",
        current_facts,
        archived_facts,
        knowledge.patterns.len(),
        knowledge.history.len()
    );
    out.push_str(&format!(
        "Last updated: {}\n",
        knowledge.updated_at.format("%Y-%m-%d %H:%M UTC")
    ));

    let rooms = knowledge.list_rooms();
    if !rooms.is_empty() {
        out.push_str("Rooms: ");
        let room_strs: Vec<String> = rooms.iter().map(|(c, n)| format!("{c}({n})")).collect();
        out.push_str(&room_strs.join(", "));
        out.push('\n');
    }

    out.push_str(&knowledge.format_summary());
    out
}

/// Per-layer lifecycle report (GL#445): item counts, effective policies, and
/// the next enforcement action for every memory layer. Read-only.
fn handle_lifecycle_report(project_root: &str) -> String {
    let policy = match load_policy_or_error() {
        Ok(p) => p,
        Err(e) => return e,
    };

    let mut out = String::from("=== Memory Lifecycle Report ===\n");

    // Knowledge layer (long-term facts, archive-only eviction).
    match ProjectKnowledge::load(project_root) {
        Some(k) => {
            let active = k.facts.iter().filter(|f| f.is_current()).count();
            let archived = k.facts.len() - active;
            out.push_str(&format!(
                "knowledge   {active} active / {archived} archived (no fact limit)\n\
                 \x20           decay {}/day, stale >{}d, consolidate-sim {:.2}\n\
                 \x20           GC: by quality only (decay, near-duplicate merge, low-confidence/stale); eviction archives, never deletes\n",
                policy.lifecycle.decay_rate,
                policy.lifecycle.stale_days,
                policy.lifecycle.similarity_threshold,
            ));
        }
        None => out.push_str("knowledge   (no store yet)\n"),
    }

    // Archive files (restorable via recall rehydration).
    let archives = lean_ctx::core::memory_lifecycle::list_archives(project_root);
    out.push_str(&format!(
        "archives    {} file(s); auto-rehydrated when recall misses\n",
        archives.len()
    ));

    // Embeddings layer (semantic index over knowledge facts).
    #[cfg(feature = "embeddings")]
    {
        let hash = lean_ctx::core::project_hash::hash_project_root(project_root);
        let n = lean_ctx::core::knowledge_embedding::KnowledgeEmbeddingIndex::load(&hash)
            .map_or(0, |idx| idx.entries.len());
        out.push_str(&format!(
            "embeddings  {n} vector(s); compacted against knowledge on remember\n"
        ));
    }
    #[cfg(not(feature = "embeddings"))]
    out.push_str("embeddings  (feature disabled in this build)\n");

    out.push_str(
        "\nLayer boundaries: session = working memory (now) | knowledge = long-term (ETL via consolidate) | providers = external (read-through)\n",
    );
    out
}

fn handle_health(project_root: &str) -> String {
    let Some(knowledge) = ProjectKnowledge::load(project_root) else {
        return "No knowledge stored. Nothing to report.".to_string();
    };

    let total = knowledge.facts.len();
    let current: Vec<_> = knowledge.facts.iter().filter(|f| f.is_current()).collect();
    let archived = total - current.len();

    let mut low_quality = 0u32;
    let mut high_quality = 0u32;
    let mut stale_candidates = 0u32;
    let mut total_quality: f32 = 0.0;
    let mut never_retrieved = 0u32;
    let mut room_counts: std::collections::HashMap<String, (u32, f32)> =
        std::collections::HashMap::new();

    let now = chrono::Utc::now();
    for f in &current {
        let q = f.quality_score();
        total_quality += q;
        if q < 0.4 {
            low_quality += 1;
        } else if q >= 0.8 {
            high_quality += 1;
        }
        if f.retrieval_count == 0 {
            never_retrieved += 1;
        }
        let age_days = (now - f.created_at).num_days();
        if age_days > 30 && f.retrieval_count == 0 {
            stale_candidates += 1;
        }

        let entry = room_counts.entry(f.category.clone()).or_insert((0, 0.0));
        entry.0 += 1;
        entry.1 += q;
    }

    let avg_quality = if current.is_empty() {
        0.0
    } else {
        total_quality / current.len() as f32
    };

    let mut out = String::from("=== Knowledge Health Report ===\n");
    out.push_str(&format!(
        "Total: {} facts ({} active, {} archived)\n",
        total,
        current.len(),
        archived
    ));
    out.push_str(&format!("Avg Quality: {avg_quality:.2}\n"));
    out.push_str(&format!(
        "Distribution: {high_quality} high (>=0.8) | {low_quality} low (<0.4)\n"
    ));
    out.push_str(&format!(
        "Stale (>30d, never retrieved): {stale_candidates}\n"
    ));
    out.push_str(&format!("Never retrieved: {never_retrieved}\n"));

    if !room_counts.is_empty() {
        out.push_str("\nRoom Balance:\n");
        let mut rooms: Vec<_> = room_counts.into_iter().collect();
        rooms.sort_by_key(|x| std::cmp::Reverse(x.1.0));
        for (cat, (count, total_q)) in &rooms {
            let avg = if *count > 0 {
                total_q / *count as f32
            } else {
                0.0
            };
            out.push_str(&format!("  {cat}: {count} facts, avg quality {avg:.2}\n"));
        }
    }

    let policy = lean_ctx::core::config::Config::load()
        .memory_policy_effective()
        .unwrap_or_default();
    out.push_str(&format!(
        "\nPolicy: no fact limit, max {} patterns\n",
        policy.knowledge.max_patterns
    ));

    out
}

fn handle_remove(project_root: &str, category: Option<&str>, key: Option<&str>) -> String {
    let Some(cat) = category else {
        return "Error: category is required for remove".to_string();
    };
    let Some(k) = key else {
        return "Error: key is required for remove".to_string();
    };
    let policy = match lean_ctx::core::config::Config::load().memory_policy_effective() {
        Ok(p) => p,
        Err(e) => {
            let path = lean_ctx::core::config::Config::path().map_or_else(
                || "~/.lean-ctx/config.toml".to_string(),
                |p| p.display().to_string(),
            );
            return format!("Error: invalid memory policy: {e}\nFix: edit {path}");
        }
    };
    // Read-modify-write under the cross-process lock (#326/#594). The embedding
    // index is a separate store, so it is synced afterwards from the committed
    // knowledge — mirroring handle_remember.
    let (knowledge, removed) = match ProjectKnowledge::mutate_locked(project_root, |knowledge| {
        knowledge.remove_fact(cat, k)
    }) {
        Ok(pair) => pair,
        Err(e) => return format!("Error: removal was not saved: {e}"),
    };

    if !removed {
        return format!("No fact found: [{cat}] {k}");
    }

    #[cfg(feature = "embeddings")]
    {
        // Serialize the embedding side-car under the same per-project lock as
        // the fact removal and compact against fresh on-disk knowledge, so a
        // concurrent `remember` cannot clobber it (issue #412).
        ProjectKnowledge::with_project_lock(project_root, || {
            if let Some(mut idx) =
                lean_ctx::core::knowledge_embedding::KnowledgeEmbeddingIndex::load(
                    &knowledge.project_hash,
                )
            {
                idx.remove(cat, k);
                let fresh = ProjectKnowledge::load(project_root);
                let kref = fresh.as_ref().unwrap_or(&knowledge);
                lean_ctx::core::knowledge_embedding::compact_against_knowledge(
                    &mut idx, kref, &policy,
                );
                let _ = idx.save();
            }
        });
    }
    #[cfg(not(feature = "embeddings"))]
    let _ = (&knowledge, &policy);

    format!("Removed [{cat}] {k}")
}

fn handle_export(project_root: &str) -> String {
    let result = lean_ctx::core::policy::runtime::with_explicit_project_source_view(
        std::path::Path::new(project_root),
        |authority| -> Result<String, String> {
            let admission =
                lean_ctx::core::knowledge::protection::KnowledgeAdmission::capture(project_root)?;
            let Some(knowledge) = ProjectKnowledge::load_for_admission(project_root, &admission)?
            else {
                admission.authorize_publication(authority)?;
                return Ok("No knowledge to export.".to_string());
            };
            if knowledge.facts.is_empty()
                && knowledge.patterns.is_empty()
                && knowledge.history.is_empty()
            {
                admission.authorize_publication(authority)?;
                return Ok("No knowledge to export.".to_string());
            }
            let data_dir = lean_ctx::core::data_dir::lean_ctx_data_dir()?;
            let export_dir = data_dir.join("exports").join("knowledge");
            let ts = Utc::now().format("%Y%m%d-%H%M%S");
            let filename = format!(
                "knowledge-{}-{ts}.json",
                short_hash(&knowledge.project_hash)
            );
            let path = export_dir.join(filename);
            let mut json = serde_json::to_string_pretty(&knowledge)
                .map_err(|_| "Export serialization failed")?;
            json.push('\n');
            admission.authorize_publication(authority)?;
            lean_ctx::config_io::write_atomic_with_backup(&path, &json)?;
            Ok(format!(
                "Export saved: {} (active facts: {}, patterns: {}, history: {})",
                path.display(),
                knowledge.facts.iter().filter(|f| f.is_current()).count(),
                knowledge.patterns.len(),
                knowledge.history.len()
            ))
        },
    );
    match result {
        Ok(Ok(message)) => message,
        Ok(Err(error)) | Err(error) => format!("Export failed: {error}"),
    }
}

fn admitted_snapshot(
    project_root: &str,
    admission: &lean_ctx::core::knowledge::protection::KnowledgeAdmission,
) -> Result<Option<lean_ctx::core::knowledge::KnowledgeSnapshot>, String> {
    let Some(knowledge) = ProjectKnowledge::load_for_admission(project_root, admission)? else {
        return Ok(None);
    };
    let visible_nodes: std::collections::HashSet<(String, String)> = knowledge
        .facts
        .iter()
        .map(|fact| (fact.category.clone(), fact.key.clone()))
        .collect();
    let relations =
        lean_ctx::core::knowledge_relations::KnowledgeRelationGraph::load(&knowledge.project_hash)
            .map(|graph| {
                graph
                    .edges
                    .into_iter()
                    .filter(|edge| {
                        visible_nodes.contains(&(edge.from.category.clone(), edge.from.key.clone()))
                            && visible_nodes
                                .contains(&(edge.to.category.clone(), edge.to.key.clone()))
                            && serde_json::to_value(edge)
                                .is_ok_and(|value| admission.admits_archive_value(&value))
                    })
                    .collect()
            })
            .unwrap_or_default();
    admission.authorize_gateway()?;
    Ok(Some(
        lean_ctx::core::knowledge::KnowledgeSnapshot::from_project(&knowledge, relations),
    ))
}

/// Exports the project's current knowledge as an Open Knowledge Format (OKF)
/// bundle — a directory of Markdown files, portable and vendor-neutral. Renders
/// from the shared [`lean_ctx::core::knowledge::KnowledgeSnapshot`], so it never
/// disagrees with a ctxpkg export on what the knowledge is. `out` is the target
/// directory (defaults to the data dir's `exports/okf/<hash>`).
pub fn handle_export_okf(project_root: &str, out: Option<&str>) -> String {
    let result = lean_ctx::core::policy::runtime::with_explicit_project_source_view(
        std::path::Path::new(project_root),
        |authority| -> Result<String, String> {
            let admission =
                lean_ctx::core::knowledge::protection::KnowledgeAdmission::capture(project_root)?;
            let Some(snapshot) = admitted_snapshot(project_root, &admission)? else {
                admission.authorize_publication(authority)?;
                return Ok("No knowledge to export.".to_string());
            };
            if snapshot.is_empty() {
                admission.authorize_publication(authority)?;
                return Ok("No knowledge to export.".to_string());
            }
            let dir = match out {
                Some(p) => std::path::PathBuf::from(p),
                None => lean_ctx::core::data_dir::lean_ctx_data_dir()?
                    .join("exports")
                    .join("okf")
                    .join(short_hash(&snapshot.project_hash)),
            };
            let bundle = lean_ctx::core::knowledge::okf::to_okf_bundle(&snapshot);
            admission.authorize_publication(authority)?;
            lean_ctx::core::knowledge::okf::write_okf_bundle(&dir, &bundle)?;
            Ok(format!(
                "OKF bundle exported: {} ({} concepts, {} patterns, {} relations)",
                dir.display(),
                snapshot.current_facts().len(),
                snapshot.patterns.len(),
                snapshot.relations.len()
            ))
        },
    );
    match result {
        Ok(Ok(message)) => message,
        Ok(Err(error)) | Err(error) => format!("Export failed: {error}"),
    }
}

/// Imports knowledge from `path`. A directory is treated as an OKF bundle; a
/// file falls back to the native JSON / simple-array / JSONL import.
pub fn handle_import(
    project_root: &str,
    path: &str,
    merge: lean_ctx::core::knowledge::ImportMerge,
    session_id: &str,
) -> String {
    if std::path::Path::new(path).is_dir() {
        return handle_import_okf(project_root, std::path::Path::new(path), merge, session_id);
    }

    let data = match std::fs::read_to_string(path) {
        Ok(d) => d,
        Err(e) => return format!("Failed to read {path}: {e}"),
    };
    let facts = match lean_ctx::core::knowledge::parse_import_data(&data) {
        Ok(f) => f,
        Err(e) => return format!("Parse error: {e}"),
    };
    match ProjectKnowledge::mutate_locked(project_root, |k| {
        k.import_facts(facts, merge, session_id)
    }) {
        Ok((_, r)) => format!(
            "Import complete: {} added, {} skipped, {} replaced",
            r.added, r.skipped, r.replaced
        ),
        Err(e) => format!("Import failed: {e}"),
    }
}

/// OKF directory import: facts via `import_facts`, patterns via `add_pattern`,
/// then relations via the relation graph — guarded so an edge is only created
/// when both endpoints are current facts (facts first, then edges).
fn handle_import_okf(
    project_root: &str,
    dir: &std::path::Path,
    merge: lean_ctx::core::knowledge::ImportMerge,
    session_id: &str,
) -> String {
    let imp = match lean_ctx::core::knowledge::okf::from_okf_dir(dir) {
        Ok(i) => i,
        Err(e) => return format!("OKF import failed: {e}"),
    };
    let policy = match load_policy_or_error() {
        Ok(p) => p,
        Err(e) => return e,
    };

    let pattern_count = imp.patterns.len();
    let (knowledge, result) = match ProjectKnowledge::mutate_locked(project_root, |k| {
        let r = k.import_facts(imp.facts, merge, session_id);
        for p in &imp.patterns {
            k.add_pattern(
                &p.pattern_type,
                &p.description,
                p.examples.clone(),
                session_id,
                &policy,
            );
        }
        r
    }) {
        Ok(v) => v,
        Err(e) => return format!("OKF import failed: {e}"),
    };

    // Guarded edges: only between facts that are current after the import.
    let current: std::collections::HashSet<(String, String)> = knowledge
        .facts
        .iter()
        .filter(|f| f.is_current())
        .map(|f| (f.category.clone(), f.key.clone()))
        .collect();
    let mut relations_added = 0usize;
    if !imp.edges.is_empty() {
        let saved = lean_ctx::core::knowledge_relations::KnowledgeRelationGraph::mutate_locked(
            project_root,
            &knowledge.project_hash,
            |graph| {
                let mut added = 0usize;
                for e in imp.edges {
                    let endpoints_current = current
                        .contains(&(e.from.category.clone(), e.from.key.clone()))
                        && current.contains(&(e.to.category.clone(), e.to.key.clone()));
                    if endpoints_current && graph.upsert_edge(e.from, e.to, e.kind, session_id) {
                        added += 1;
                    }
                }
                Some(added)
            },
        );
        match saved {
            Ok(added) => relations_added = added.unwrap_or_default(),
            Err(err) => tracing::warn!("OKF import: relations save failed: {err}"),
        }
    }

    let mut out = format!(
        "OKF import: {} added, {} skipped, {} replaced, {pattern_count} patterns, {relations_added} relations",
        result.added, result.skipped, result.replaced
    );
    let warnings = lean_ctx::core::knowledge::okf::lint_okf_bundle(dir);
    if !warnings.is_empty() {
        out.push_str(&format!("\nLint warnings ({}):", warnings.len()));
        for w in warnings.iter().take(10) {
            out.push_str(&format!("\n  - {w}"));
        }
    }
    out
}

fn handle_consolidate(project_root: &str) -> String {
    match consolidate_project_knowledge(project_root) {
        Ok(report) => format_consolidation_report(&report),
        Err(e) => e,
    }
}

/// Dry-run consolidate: preview imports + reclaim with zero writes (#995).
fn handle_consolidate_preview(project_root: &str) -> String {
    match consolidate_project_knowledge_with(
        project_root,
        &ConsolidateOptions::manual().into_dry_run(),
    ) {
        Ok(report) => format_consolidation_report(&report),
        Err(e) => e,
    }
}

/// Explicit cross-store restore from archive (#995 Phase 6). `store` selects a
/// single store (all when `None`); `query` filters by substring; `limit` caps
/// the total restored (default [`DEFAULT_RESTORE_LIMIT`]).
fn handle_restore(
    project_root: &str,
    store: Option<&str>,
    query: Option<&str>,
    limit: Option<usize>,
) -> String {
    let store = match store {
        Some(s) if lean_ctx::core::memory_archive::MemoryStore::is_retired(s) => {
            return lean_ctx::core::memory_archive::RETIRED_PROCEDURES_STORE_NOTICE.to_string();
        }
        Some(s) => match lean_ctx::core::memory_archive::MemoryStore::parse(s) {
            Some(ms) => Some(ms),
            None => {
                return format!("Unknown store: {s}. Use: facts, history, patterns");
            }
        },
        None => None,
    };
    let opts = RestoreOptions::new(
        store,
        query.map(str::to_string),
        limit.unwrap_or(DEFAULT_RESTORE_LIMIT),
    );
    match run_restore(project_root, &opts) {
        Ok(report) => format_restore_report(&report),
        Err(e) => e,
    }
}

fn handle_timeline(project_root: &str, category: Option<&str>) -> Result<String, String> {
    let Some(knowledge) = ProjectKnowledge::load(project_root) else {
        return Ok("No knowledge stored yet.".to_string());
    };

    let policy = load_policy_or_error()?;

    let Some(cat) = category else {
        return Err("Error: category is required for timeline".to_string());
    };

    let facts = knowledge.timeline(cat);
    if facts.is_empty() {
        return Ok(format!("No history for category '{cat}'."));
    }

    let mut ordered: Vec<&lean_ctx::core::knowledge::KnowledgeFact> = facts;
    ordered.sort_by(|a, b| {
        let a_start = a.valid_from.unwrap_or(a.created_at);
        let b_start = b.valid_from.unwrap_or(b.created_at);
        a_start
            .cmp(&b_start)
            .then_with(|| a.last_confirmed.cmp(&b.last_confirmed))
            .then_with(|| a.key.cmp(&b.key))
            .then_with(|| a.value.cmp(&b.value))
    });

    let total = ordered.len();
    let limit = policy.knowledge.timeline_limit;
    if ordered.len() > limit {
        ordered = ordered[ordered.len() - limit..].to_vec();
    }
    // Only what may be delivered now (see `fact_served`).
    ordered.retain(|f| fact_served(project_root, &f.category, &f.key, &f.value));

    let mut out = format!(
        "Timeline [{cat}] (showing {}/{} entries):\n",
        ordered.len(),
        total
    );
    for f in &ordered {
        let status = if f.is_current() {
            "CURRENT"
        } else {
            "archived"
        };
        let valid_range = match (f.valid_from, f.valid_until) {
            (Some(from), Some(until)) => format!(
                "{} → {}",
                from.format("%Y-%m-%d %H:%M"),
                until.format("%Y-%m-%d %H:%M")
            ),
            (Some(from), None) => format!("{} → now", from.format("%Y-%m-%d %H:%M")),
            _ => "unknown".to_string(),
        };
        out.push_str(&format!(
            "  {} = {} [{status}] ({valid_range}) conf={:.0}% x{}\n",
            f.key,
            f.as_delivered(f.value.clone()),
            f.confidence * 100.0,
            f.confirmation_count
        ));
    }
    Ok(out)
}

fn handle_rooms(project_root: &str) -> String {
    let Some(knowledge) = ProjectKnowledge::load(project_root) else {
        return "No knowledge stored yet.".to_string();
    };

    let policy = match load_policy_or_error() {
        Ok(p) => p,
        Err(e) => return e,
    };

    let rooms = knowledge.list_rooms();
    if rooms.is_empty() {
        return "No knowledge rooms yet. Use ctx_knowledge(action=\"remember\", category=\"...\") to create rooms.".to_string();
    }

    let mut rooms = rooms;
    rooms.sort_by(|a, b| b.1.cmp(&a.1).then_with(|| a.0.cmp(&b.0)));
    let total = rooms.len();
    rooms.truncate(policy.knowledge.rooms_limit);

    let mut out = format!(
        "Knowledge Rooms (showing {}/{} rooms, project: {}):\n",
        rooms.len(),
        total,
        short_hash(&knowledge.project_hash)
    );
    for (cat, count) in &rooms {
        out.push_str(&format!("  [{cat}] {count} fact(s)\n"));
    }
    out
}

fn handle_bridge_publish(project_root: &str, session_id: &str) -> String {
    let knowledge = ProjectKnowledge::load_or_create(project_root);
    let published = lean_ctx::core::knowledge_bridge::KnowledgeBridge::mutate_locked(
        &knowledge.project_hash,
        |bridge| {
            (
                bridge.publish(session_id, &knowledge.facts),
                bridge.shared_facts.len(),
            )
        },
    );
    match published {
        Ok((count, total)) => {
            format!("Published {count} fact(s) to bridge (total: {total}, agent: {session_id})")
        }
        Err(e) => format!("Error: context publication was not saved: {e}"),
    }
}

fn handle_bridge_pull(project_root: &str, session_id: &str) -> String {
    let project_hash = lean_ctx::core::project_hash::hash_project_root(project_root);
    let bridge = lean_ctx::core::knowledge_bridge::KnowledgeBridge::load_or_create(&project_hash);
    let entries = bridge.pull(session_id);
    if entries.is_empty() {
        return "No facts available from other agents.".to_string();
    }

    let policy = match load_policy_or_error() {
        Ok(p) => p,
        Err(e) => return e,
    };

    let missing = |target: &ProjectKnowledge,
                   entry: &lean_ctx::core::knowledge_bridge::BridgeEntry| {
        let fact = lean_ctx::core::knowledge_bridge::KnowledgeBridge::entry_to_fact(entry);
        let present = target
            .facts
            .iter()
            .any(|f| f.is_current() && f.category == fact.category && f.key == fact.key);
        (!present).then_some(fact)
    };
    // Nothing to import: the store is neither locked nor rewritten.
    let current = ProjectKnowledge::load_or_create(project_root);
    if entries
        .iter()
        .all(|entry| missing(&current, entry).is_none())
    {
        return format!(
            "Bridge has {} fact(s) from other agents, but all already exist locally.",
            entries.len()
        );
    }

    // The existence check and the import run again on the store as it is
    // inside the project lock, so a parallel writer's facts are never
    // overwritten.
    let imported = ProjectKnowledge::mutate_locked(project_root, |target| {
        let mut imported = 0u32;
        for entry in &entries {
            if let Some(fact) = missing(target, entry) {
                target.remember(
                    &fact.category,
                    &fact.key,
                    &fact.value,
                    session_id,
                    fact.confidence,
                    &policy,
                );
                imported += 1;
            }
        }
        imported
    });

    match imported {
        Ok((_, 0)) => format!(
            "Bridge has {} fact(s) from other agents, but all already exist locally.",
            entries.len()
        ),
        Ok((_, imported)) => format!(
            "Pulled {imported}/{} fact(s) from bridge into local knowledge.",
            entries.len()
        ),
        Err(e) => format!("Error: context import was not saved: {e}"),
    }
}

fn handle_bridge_status(project_root: &str) -> String {
    let knowledge = ProjectKnowledge::load_or_create(project_root);
    let bridge =
        lean_ctx::core::knowledge_bridge::KnowledgeBridge::load_or_create(&knowledge.project_hash);
    bridge.summary()
}

fn handle_wakeup(project_root: &str) -> String {
    let Some(knowledge) = ProjectKnowledge::load(project_root) else {
        return "No knowledge for wake-up briefing.".to_string();
    };
    let aaak = knowledge.format_aaak();
    if aaak.is_empty() {
        return "No knowledge yet. Start using ctx_knowledge(action=\"remember\") to build project memory.".to_string();
    }
    format!("{WAKEUP_HEAD}{aaak}")
}

const WAKEUP_HEAD: &str = "WAKE-UP BRIEFING:\n";

/// The delta form of a wake-up briefing, in the one channel that has a
/// history: a tool result stays in the caller's context.
///
/// The Engine cannot see a context. What it can check is the existing
/// possession proof of a request — the presenter capability its host showed
/// (`core::archive::presented`) — and what left the release point of the
/// tool pipeline. The short answer is given only when all three hold:
///
/// 1. the request shows an issued presenter capability that may still
///    present (`shown_presenter_reference`); the capability of the process,
///    which every connection without one shares, never counts;
/// 2. a briefing with exactly this admitted text was RELEASED to a request of
///    that same presenter ([`note_wakeup_release`], called where the result
///    blocks are the bytes the client receives — not when the text is built);
/// 3. the caller names the hash of that text in `value`.
///
/// Anything else is answered in full: no capability, another presenter,
/// nothing on record (another process, a result that was withheld, replaced,
/// shortened or compressed after it was built), a record that cannot be read in time, a
/// changed memory or policy (another admitted text), no or another hash.
/// `admitted` is the briefing after `protect_active` and `admit_recovered`.
fn wakeup_delta(held: Option<&str>, admitted: String) -> String {
    let holder = lean_ctx::core::archive::presented::shown_presenter_reference();
    wakeup_delta_for(holder.as_deref(), held, admitted)
}

const WAKEUP_HASH_LINE: &str = "\n[memory hash ";

fn wakeup_hash(briefing: &str) -> String {
    blake3::hash(briefing.as_bytes()).to_hex()[..16].to_string()
}

fn wakeup_delta_for(holder: Option<&str>, held: Option<&str>, admitted: String) -> String {
    let Some(holder) = holder else {
        // No possession proof exists for this request: the briefing as before.
        return admitted;
    };
    if !admitted.starts_with(WAKEUP_HEAD)
        || admitted.contains(lean_ctx::core::sanitize::FENCE_REFUSAL)
    {
        return admitted;
    }
    let hash = wakeup_hash(&admitted);
    if held.map(str::trim) == Some(hash.as_str()) && wakeup_released(holder, &hash) {
        return format!(
            "{WAKEUP_HEAD}[project memory unchanged since the briefing with hash {hash}]"
        );
    }
    wakeup_full(&admitted, &hash)
}

/// The full answer: the admitted briefing and, as its last line, its hash.
fn wakeup_full(admitted: &str, hash: &str) -> String {
    format!(
        "{admitted}{WAKEUP_HASH_LINE}{hash} — while this briefing is still in your context, \
         ctx_knowledge(action=\"wakeup\", value=\"{hash}\") answers \"unchanged\" instead of repeating it]"
    )
}

type WakeupReleases = std::sync::Arc<tokio::sync::RwLock<Vec<(String, String)>>>;

/// Briefings released by this process: (presenter reference, hash). Bounded,
/// in memory only: a new process has released nothing.
fn wakeup_releases() -> &'static WakeupReleases {
    static RELEASED: std::sync::OnceLock<WakeupReleases> = std::sync::OnceLock::new();
    RELEASED.get_or_init(WakeupReleases::default)
}

/// Whether a briefing with this hash was released to this presenter. A record
/// that cannot be read within the lock bound counts as none.
fn wakeup_released(holder: &str, hash: &str) -> bool {
    crate::server::bounded_lock::read(wakeup_releases(), "ctx_knowledge wakeup release read")
        .is_some_and(|released| {
            released
                .iter()
                .any(|(presenter, released_hash)| presenter == holder && released_hash == hash)
        })
}

/// The release point of the tool pipeline reports the text blocks a client
/// receives for a call that did not fail. A block counts as a released
/// briefing only when it holds, byte for byte and in one piece, the full
/// answer this module builds for the briefing it contains — from the head to
/// the end of the closing hash line. Text the pipeline put before or after it
/// (a notice, a hint, a checkpoint) takes nothing from the briefing and does
/// not matter; a block in which the answer was shortened anywhere (the
/// closing line included), compressed, redacted or replaced is no such block.
/// A request without an issued presenter capability records nothing.
pub(crate) fn note_wakeup_release(delivered_blocks: &[&str]) {
    let Some(holder) = lean_ctx::core::archive::presented::shown_presenter_reference() else {
        return;
    };
    note_wakeup_release_for(&holder, delivered_blocks);
}

fn note_wakeup_release_for(holder: &str, delivered_blocks: &[&str]) {
    const REMEMBERED: usize = 64;
    for block in delivered_blocks {
        // Head and marker only locate the answer; what counts is that the
        // block holds it whole, from the head to the end of its closing line.
        let Some(answer) = block.find(WAKEUP_HEAD).map(|start| &block[start..]) else {
            continue;
        };
        let Some((briefing, _)) = answer.rsplit_once(WAKEUP_HASH_LINE) else {
            continue;
        };
        let hash = wakeup_hash(briefing);
        if !answer.starts_with(&wakeup_full(briefing, &hash)) {
            continue;
        }
        let entry = (holder.to_string(), hash);
        // Not recorded within the lock bound: the next wake-up is answered in full.
        let Some(mut released) = crate::server::bounded_lock::write(
            wakeup_releases(),
            "ctx_knowledge wakeup release write",
        ) else {
            return;
        };
        if !released.contains(&entry) {
            if released.len() == REMEMBERED {
                released.remove(0);
            }
            released.push(entry);
        }
    }
}