mod incremental;
pub(crate) use incremental::SourceTask;
use std::{
    collections::{HashMap, HashSet},
    fs::{File, OpenOptions},
    path::{Path, PathBuf},
    sync::Arc,
};

use anyhow::{ensure, Context, Result};
use fs2::FileExt;
use rusqlite::{params, Connection, OptionalExtension};
use searchi_core::metrics::{MetricsMode, SpanToken, TraceCollector};
use searchi_core::{IndexedPassage, SearchOptions, SearchResult, SourceLocation};
use searchi_semantic::TextWindow;
use sha2::{Digest, Sha256};
use usearch::{Index, IndexOptions, MetricKind, ScalarKind};

pub(crate) const MAX_SCAN_CHUNKS: usize = 100_000;
pub(crate) const MIN_COSINE: f32 = 0.25;

#[derive(Clone, PartialEq, Eq)]
struct FilterKey {
    folder: Option<String>,
    extension: Option<String>,
    min_size: Option<i64>,
    max_size: Option<i64>,
    modified_after: Option<i64>,
    modified_before: Option<i64>,
    min_duration: Option<u32>,
    max_duration: Option<u32>,
    source_type: Option<String>,
    code_only: bool,
}

struct EligibilityCache {
    generation: i64,
    revision: i64,
    filter: FilterKey,
    keys: Arc<HashSet<u64>>,
    by_path: HashMap<String, Vec<u64>>,
}

pub(crate) struct Store {
    connection: Connection,
    lock_path: PathBuf,
    dimensions: usize,
    ann_cache: Option<(i64, Index)>,
    eligibility_cache: Option<EligibilityCache>,
}

pub(crate) struct BuildLock(File, PathBuf);
impl Drop for BuildLock {
    fn drop(&mut self) {
        let _ = FileExt::unlock(&self.0);
    }
}

pub(crate) fn content_hash(text: &str) -> String {
    #[cfg(test)]
    HASH_CALLS.with(|count| count.set(count.get() + 1));
    format!("{:x}", Sha256::digest(text.as_bytes()))
}

#[cfg(test)]
thread_local! { static HASH_CALLS:std::cell::Cell<usize>=const {std::cell::Cell::new(0)}; }
#[cfg(test)]
thread_local! { static MEDIA_STAT_CALLS:std::cell::Cell<usize>=const {std::cell::Cell::new(0)}; }

impl Store {
    pub(crate) fn active_fingerprint(&self) -> Result<Option<String>> {
        Ok(self.connection.query_row("SELECT g.fingerprint FROM semantic_meta m JOIN semantic_generations g ON g.id=m.active_generation WHERE m.singleton=1",[],|r|r.get(0)).optional()?)
    }
    pub(crate) fn open(db: &Path, dimensions: usize) -> Result<Self> {
        ensure!(
            (1..=4096).contains(&dimensions),
            "Embedding dimensions must be between 1 and 4096"
        );
        ensure!(
            db != Path::new(":memory:"),
            "Hybrid search requires a persistent database path"
        );
        let mut connection = Connection::open(db)?;
        connection.busy_timeout(std::time::Duration::from_secs(5))?;
        connection.execute_batch("PRAGMA foreign_keys=ON;")?;
        let initialization =
            connection.transaction_with_behavior(rusqlite::TransactionBehavior::Immediate)?;
        initialization.execute_batch(
            "CREATE TABLE IF NOT EXISTS semantic_meta (
            singleton INTEGER PRIMARY KEY CHECK(singleton=1), schema_version INTEGER NOT NULL,
            active_generation INTEGER, corpus_revision INTEGER NOT NULL DEFAULT 0, dirty_floor INTEGER NOT NULL DEFAULT 0);
            INSERT OR IGNORE INTO semantic_meta(singleton,schema_version) VALUES(1,5);",
        )?;
        let version: i64 = initialization.query_row(
            "SELECT schema_version FROM semantic_meta WHERE singleton=1",
            [],
            |row| row.get(0),
        )?;
        ensure!(
            (1..=7).contains(&version),
            "Unsupported semantic schema version {version}"
        );
        initialization.execute_batch("
            CREATE TABLE IF NOT EXISTS semantic_generations(id INTEGER PRIMARY KEY, fingerprint TEXT NOT NULL, dimensions INTEGER NOT NULL, corpus_revision INTEGER NOT NULL DEFAULT 0, ann_blob BLOB, ann_sha256 TEXT);
            CREATE TABLE IF NOT EXISTS semantic_chunks(
                generation INTEGER NOT NULL REFERENCES semantic_generations(id) ON DELETE CASCADE,
                passage_id INTEGER NOT NULL, ordinal INTEGER NOT NULL,
                path TEXT NOT NULL, kind TEXT NOT NULL, number INTEGER NOT NULL,
                content_hash TEXT NOT NULL, start_byte INTEGER NOT NULL, end_byte INTEGER NOT NULL,
                snippet TEXT NOT NULL, vector BLOB NOT NULL,
                PRIMARY KEY(generation,passage_id,ordinal));")?;
        if version < 5 {
            for (table,column,alter) in [
                ("semantic_meta","corpus_revision","ALTER TABLE semantic_meta ADD COLUMN corpus_revision INTEGER NOT NULL DEFAULT 0"),
                ("semantic_meta","dirty_floor","ALTER TABLE semantic_meta ADD COLUMN dirty_floor INTEGER NOT NULL DEFAULT 0"),
                ("semantic_generations","dimensions","ALTER TABLE semantic_generations ADD COLUMN dimensions INTEGER NOT NULL DEFAULT 384"),
                ("semantic_generations","corpus_revision","ALTER TABLE semantic_generations ADD COLUMN corpus_revision INTEGER NOT NULL DEFAULT 0"),
                ("semantic_generations","ann_blob","ALTER TABLE semantic_generations ADD COLUMN ann_blob BLOB"),
                ("semantic_generations","ann_sha256","ALTER TABLE semantic_generations ADD COLUMN ann_sha256 TEXT"),
            ] {
                let exists:bool=initialization.query_row("SELECT EXISTS(SELECT 1 FROM pragma_table_info(?1) WHERE name=?2)",params![table,column],|row| row.get(0))?;
                if !exists { initialization.execute_batch(alter)?; }
            }
            initialization.execute_batch("DROP TRIGGER IF EXISTS semantic_files_insert;
                DROP TRIGGER IF EXISTS semantic_files_update; DROP TRIGGER IF EXISTS semantic_files_delete;")?;
        }
        initialization.execute_batch(
            "CREATE TABLE IF NOT EXISTS semantic_dirty_paths(path TEXT PRIMARY KEY, revision INTEGER NOT NULL);
            CREATE INDEX IF NOT EXISTS semantic_dirty_revision ON semantic_dirty_paths(revision);
            CREATE INDEX IF NOT EXISTS semantic_chunk_path ON semantic_chunks(generation,path);
            CREATE TRIGGER IF NOT EXISTS semantic_files_insert AFTER INSERT ON files BEGIN
            UPDATE semantic_meta SET corpus_revision=corpus_revision+1 WHERE singleton=1;
            INSERT INTO semantic_dirty_paths(path,revision) VALUES(new.path,(SELECT corpus_revision FROM semantic_meta WHERE singleton=1))
                ON CONFLICT(path) DO UPDATE SET revision=excluded.revision; END;
            CREATE TRIGGER IF NOT EXISTS semantic_files_update AFTER UPDATE ON files BEGIN
            UPDATE semantic_meta SET corpus_revision=corpus_revision+1 WHERE singleton=1;
            INSERT INTO semantic_dirty_paths(path,revision) VALUES(old.path,(SELECT corpus_revision FROM semantic_meta WHERE singleton=1))
                ON CONFLICT(path) DO UPDATE SET revision=excluded.revision;
            INSERT INTO semantic_dirty_paths(path,revision) VALUES(new.path,(SELECT corpus_revision FROM semantic_meta WHERE singleton=1))
                ON CONFLICT(path) DO UPDATE SET revision=excluded.revision; END;
            CREATE TRIGGER IF NOT EXISTS semantic_files_delete AFTER DELETE ON files BEGIN
            UPDATE semantic_meta SET corpus_revision=corpus_revision+1 WHERE singleton=1;
            INSERT INTO semantic_dirty_paths(path,revision) VALUES(old.path,(SELECT corpus_revision FROM semantic_meta WHERE singleton=1))
                ON CONFLICT(path) DO UPDATE SET revision=excluded.revision; END;
            UPDATE semantic_meta SET schema_version=6 WHERE singleton=1;",
        )?;
        for (column, declaration) in [
            ("source_type", "TEXT NOT NULL DEFAULT 'text'"),
            ("file_size", "INTEGER"),
            ("file_mtime", "INTEGER"),
        ] {
            let exists: bool = initialization.query_row(
                "SELECT EXISTS(SELECT 1 FROM pragma_table_info('semantic_chunks') WHERE name=?1)",
                [column],
                |r| r.get(0),
            )?;
            if !exists {
                initialization.execute_batch(&format!(
                    "ALTER TABLE semantic_chunks ADD COLUMN {column} {declaration}"
                ))?;
            }
        }
        initialization.execute_batch("CREATE TABLE IF NOT EXISTS semantic_media_errors(generation INTEGER NOT NULL REFERENCES semantic_generations(id) ON DELETE CASCADE,path TEXT NOT NULL,message TEXT NOT NULL,PRIMARY KEY(generation,path))")?;
        incremental::migrate(&initialization)?;
        initialization.commit()?;
        let canonical = db.canonicalize()?;
        let lock_path = PathBuf::from(format!("{}.semantic.lock", canonical.to_string_lossy()));
        Ok(Self {
            connection,
            lock_path,
            dimensions,
            ann_cache: None,
            eligibility_cache: None,
        })
    }

    pub(crate) fn build_lock(&self) -> Result<BuildLock> {
        let file = OpenOptions::new()
            .read(true)
            .write(true)
            .create(true)
            .truncate(false)
            .open(&self.lock_path)?;
        file.try_lock_exclusive()
            .context("Another semantic rebuild is running")?;
        Ok(BuildLock(file, self.lock_path.clone()))
    }

    #[cfg(test)]
    pub(crate) fn begin(&mut self, fingerprint: &str) -> Result<i64> {
        let transaction = self.connection.transaction()?;
        // Only called while holding the cross-process lock: abandoned staging
        // generations may be removed safely after a crash.
        transaction.execute("DELETE FROM semantic_generations WHERE id != COALESCE((SELECT active_generation FROM semantic_meta WHERE singleton=1),-1)", [])?;
        transaction.execute(
            "INSERT INTO semantic_generations(fingerprint,dimensions,corpus_revision) SELECT ?1,?2,corpus_revision FROM semantic_meta WHERE singleton=1",
            params![fingerprint, self.dimensions as i64],
        )?;
        let id = transaction.last_insert_rowid();
        transaction.commit()?;
        Ok(id)
    }

    pub(crate) fn media_batch(&self, after: i64) -> Result<Vec<(i64, String, i64, i64)>> {
        let mut q = self.connection.prepare(
            "SELECT rowid,path,size,mtime FROM files WHERE rowid>?1 ORDER BY rowid LIMIT 64",
        )?;
        let rows = q
            .query_map([after], |r| {
                Ok((r.get(0)?, r.get(1)?, r.get(2)?, r.get(3)?))
            })?
            .collect::<rusqlite::Result<Vec<_>>>()?;
        Ok(rows)
    }
    pub(crate) fn media_failure(&self, generation: i64, path: &str, message: &str) -> Result<()> {
        self.connection.execute(
            "DELETE FROM semantic_chunks WHERE generation=?1 AND path=?2 AND source_type!='text'",
            params![generation, path],
        )?;
        self.connection.execute("INSERT OR REPLACE INTO semantic_media_errors(generation,path,message) VALUES(?1,?2,?3)",params![generation,path,message.chars().take(2048).collect::<String>()])?;
        Ok(())
    }
    #[allow(clippy::too_many_arguments)]
    pub(crate) fn insert_media(
        &self,
        generation: i64,
        file_id: i64,
        ordinal: usize,
        identity: &searchi_media::MediaIdentity,
        source_type: &str,
        timestamp: u32,
        vector: &[f32],
    ) -> Result<()> {
        ensure!(
            vector.len() == self.dimensions && vector.iter().all(|v| v.is_finite()),
            "Invalid media embedding"
        );
        let norm = vector.iter().map(|v| v * v).sum::<f32>().sqrt();
        ensure!(
            (norm - 1.).abs() < 1e-3,
            "Media embeddings must be normalized"
        );
        let path = identity.path.to_string_lossy();
        let valid:bool=self.connection.query_row("SELECT EXISTS(SELECT 1 FROM files WHERE rowid=?1 AND path=?2 AND size=?3 AND mtime=?4)",params![file_id,path,identity.bytes as i64,identity.modified_ns],|r|r.get(0))?;
        ensure!(valid, "Media file changed since filesystem indexing");
        let kind = if source_type == "image" {
            "image"
        } else {
            "timestamp_ms"
        };
        let snippet = if source_type == "image" {
            "Image content".to_string()
        } else {
            format!(
                "{} content at {:.3} seconds",
                source_type,
                f64::from(timestamp) / 1000.
            )
        };
        let bytes: Vec<u8> = vector.iter().flat_map(|v| v.to_le_bytes()).collect();
        self.connection.execute("INSERT INTO semantic_chunks(generation,passage_id,ordinal,path,kind,number,content_hash,start_byte,end_byte,snippet,vector,source_type,file_size,file_mtime) VALUES(?1,?2,?3,?4,?5,?6,?7,0,0,?8,?9,?10,?11,?12)",params![generation,-file_id,ordinal as i64,path,kind,timestamp,identity.sha256,snippet,bytes,source_type,identity.bytes as i64,identity.modified_ns])?;
        Ok(())
    }

    pub(crate) fn insert(
        &mut self,
        generation: i64,
        passage: &IndexedPassage,
        first_ordinal: usize,
        windows: &[TextWindow],
        vectors: &[Vec<f32>],
    ) -> Result<()> {
        ensure!(
            windows.len() == vectors.len(),
            "Window and embedding counts differ"
        );
        let hash = content_hash(&passage.text);
        let transaction = self.connection.transaction()?;
        for (i, (window, vector)) in windows.iter().zip(vectors).enumerate() {
            ensure!(
                vector.len() == self.dimensions && vector.iter().all(|v| v.is_finite()),
                "Invalid persisted vector"
            );
            let norm = vector.iter().map(|value| value * value).sum::<f32>().sqrt();
            ensure!(
                norm.is_finite() && (norm - 1.0).abs() < 1e-3,
                "Persisted embeddings must be L2 normalized"
            );
            ensure!(
                passage.text.get(window.start_byte..window.end_byte) == Some(window.text.as_str()),
                "Window does not match passage source range"
            );
            let bytes: Vec<u8> = vector
                .iter()
                .flat_map(|value| value.to_le_bytes())
                .collect();
            transaction.execute("INSERT INTO semantic_chunks(generation,passage_id,ordinal,path,kind,number,content_hash,start_byte,end_byte,snippet,vector)
                VALUES(?1,?2,?3,?4,?5,?6,?7,?8,?9,?10,?11)", params![generation, passage.id,
                (first_ordinal+i) as i64, passage.path, passage.source.kind, passage.source.number,
                hash, window.start_byte as i64, window.end_byte as i64, window.text, bytes])?;
        }
        transaction.commit()?;
        Ok(())
    }

    #[cfg(test)]
    pub(crate) fn activate(&mut self, generation: i64) -> Result<()> {
        self.activate_revision(generation, None)
    }

    fn activate_revision(&mut self, generation: i64, revision: Option<i64>) -> Result<()> {
        // A failed graph build or serialization leaves the old generation active.
        let ann = self.build_ann(generation)?;
        let length = ann.serialized_length();
        ensure!(
            length <= 512 * 1024 * 1024,
            "Serialized ANN exceeds 512 MiB generation budget"
        );
        let mut serialized = vec![0_u8; length];
        ann.save_to_buffer(&mut serialized)?;
        let checksum = format!("{:x}", Sha256::digest(&serialized));
        let transaction = self
            .connection
            .transaction_with_behavior(rusqlite::TransactionBehavior::Immediate)?;
        if let Some(expected) = revision {
            let current: i64 = transaction.query_row(
                "SELECT corpus_revision FROM semantic_meta WHERE singleton=1",
                [],
                |r| r.get(0),
            )?;
            ensure!(
                current == expected,
                "Indexed corpus changed during semantic rebuild; retry required"
            );
            incremental::validate_completion(&transaction, generation)?;
        }
        ensure!(
            transaction.query_row(
                "SELECT EXISTS(SELECT 1 FROM semantic_generations WHERE id=?1)",
                [generation],
                |row| row.get::<_, bool>(0)
            )?,
            "Missing staging generation"
        );
        transaction.execute(
            "UPDATE semantic_generations SET ann_blob=?1,ann_sha256=?2 WHERE id=?3",
            params![serialized, checksum, generation],
        )?;
        transaction.execute(
            "UPDATE semantic_meta SET active_generation=?1 WHERE singleton=1",
            [generation],
        )?;
        transaction.execute(
            "DELETE FROM semantic_generations WHERE id!=?1",
            [generation],
        )?;
        transaction.execute_batch("UPDATE semantic_meta SET dirty_floor=max(dirty_floor,corpus_revision-100000) WHERE singleton=1;
            DELETE FROM semantic_dirty_paths WHERE revision<(SELECT dirty_floor FROM semantic_meta WHERE singleton=1);")?;
        transaction.commit()?;
        self.ann_cache = Some((generation, ann));
        self.eligibility_cache = None;
        Ok(())
    }

    fn new_ann(&self) -> Result<Index> {
        Ok(Index::new(&IndexOptions {
            dimensions: self.dimensions,
            metric: MetricKind::Cos,
            quantization: ScalarKind::F32,
            connectivity: 16,
            expansion_add: 128,
            expansion_search: 64,
            multi: false,
        })?)
    }

    fn build_ann(&self, generation: i64) -> Result<Index> {
        let count: usize = self.connection.query_row(
            "SELECT count(*) FROM semantic_chunks WHERE generation=?1",
            [generation],
            |row| row.get(0),
        )?;
        ensure!(
            count <= MAX_SCAN_CHUNKS,
            "ANN generation exceeds {MAX_SCAN_CHUNKS} chunks"
        );
        let ann = self.new_ann()?;
        ann.reserve_capacity_and_threads(count.max(1), 1)?;
        let mut statement = self.connection.prepare(
            "SELECT rowid,vector FROM semantic_chunks WHERE generation=?1 ORDER BY rowid",
        )?;
        let mut rows = statement.query([generation])?;
        while let Some(row) = rows.next()? {
            let key: i64 = row.get(0)?;
            let bytes: Vec<u8> = row.get(1)?;
            ensure!(
                bytes.len() == self.dimensions * 4,
                "Invalid staging embedding length"
            );
            let vector: Vec<f32> = bytes
                .as_chunks::<4>()
                .0
                .iter()
                .map(|bytes| f32::from_le_bytes(*bytes))
                .collect();
            ensure!(
                vector.iter().all(|v| v.is_finite()),
                "Invalid staging embedding values"
            );
            ann.add(u64::try_from(key)?, &vector)?;
        }
        Ok(ann)
    }

    #[cfg(test)]
    pub(crate) fn abandon(&mut self, generation: i64) -> Result<()> {
        self.connection.execute("DELETE FROM semantic_generations WHERE id=?1 AND id!=COALESCE((SELECT active_generation FROM semantic_meta WHERE singleton=1),-1)", [generation])?;
        Ok(())
    }

    pub(crate) fn search(
        &mut self,
        query: &[f32],
        fingerprint: &str,
        limit: usize,
        options: &SearchOptions,
    ) -> Result<Vec<SearchResult>> {
        self.search_origin(query, fingerprint, limit, options, None)
    }
    pub(crate) fn search_origin(
        &mut self,
        query: &[f32],
        fingerprint: &str,
        limit: usize,
        options: &SearchOptions,
        source_type: Option<&str>,
    ) -> Result<Vec<SearchResult>> {
        let mut trace = TraceCollector::new(MetricsMode::Basic);
        self.search_origin_traced(
            query,
            fingerprint,
            limit,
            options,
            source_type,
            &mut trace,
            None,
        )
    }
    #[allow(clippy::too_many_arguments)]
    pub(crate) fn search_origin_traced(
        &mut self,
        query: &[f32],
        fingerprint: &str,
        limit: usize,
        options: &SearchOptions,
        source_type: Option<&str>,
        trace: &mut TraceCollector,
        parent: Option<SpanToken>,
    ) -> Result<Vec<SearchResult>> {
        trace.timed("semantic.retrieval", parent, |trace, parent| {
            self.search_inner(
                query,
                fingerprint,
                limit,
                options,
                source_type,
                trace,
                parent,
            )
        })
    }
    #[allow(clippy::too_many_arguments)]
    fn search_inner(
        &mut self,
        query: &[f32],
        fingerprint: &str,
        limit: usize,
        options: &SearchOptions,
        source_type: Option<&str>,
        trace: &mut TraceCollector,
        parent: Option<SpanToken>,
    ) -> Result<Vec<SearchResult>> {
        ensure!(
            query.len() == self.dimensions && query.iter().all(|v| v.is_finite()),
            "Invalid query vector"
        );
        if limit == 0 {
            return Ok(Vec::new());
        }
        // A consistent read snapshot covers eligibility and materialization.
        let generation_span = trace.begin("semantic.generation_snapshot", parent);
        let snapshot = self.connection.unchecked_transaction()?;
        let active:Option<i64>=snapshot.query_row("SELECT g.id FROM semantic_generations g JOIN semantic_meta m ON m.active_generation=g.id WHERE g.fingerprint=?1 AND g.dimensions=?2",
            params![fingerprint,self.dimensions as i64],|row|row.get(0)).optional()?;
        let Some(active) = active else {
            return Ok(Vec::new());
        };
        trace.end(generation_span, Default::default());
        let ann_load = trace.begin("semantic.ann_load", parent);
        trace.counter(
            ann_load,
            "cache_hit",
            u64::from(
                self.ann_cache
                    .as_ref()
                    .is_some_and(|(generation, _)| *generation == active),
            ),
        );
        if !self
            .ann_cache
            .as_ref()
            .is_some_and(|(generation, _)| *generation == active)
        {
            let blob_span = trace.begin("semantic.ann_blob_read", ann_load);
            let length: Option<usize> = snapshot.query_row(
                "SELECT length(ann_blob) FROM semantic_generations WHERE id=?1",
                [active],
                |row| row.get(0),
            )?;
            ensure!(
                length.is_some_and(|bytes| bytes <= 512 * 1024 * 1024),
                "Missing or oversized ANN generation; rebuild embeddings explicitly"
            );
            let (serialized, checksum): (Vec<u8>, String) = snapshot.query_row(
                "SELECT ann_blob,ann_sha256 FROM semantic_generations WHERE id=?1",
                [active],
                |row| Ok((row.get(0)?, row.get(1)?)),
            )?;
            trace.counter(blob_span, "bytes", serialized.len() as u64);
            trace.end(blob_span, Default::default());
            let checksum_span = trace.begin("semantic.ann_checksum", ann_load);
            ensure!(
                format!("{:x}", Sha256::digest(&serialized)) == checksum,
                "ANN generation SHA256 mismatch; rebuild embeddings explicitly"
            );
            trace.end(checksum_span, Default::default());
            let deserialize_span = trace.begin("semantic.ann_deserialize", ann_load);
            let ann = self.new_ann()?;
            ann.load_from_buffer(&serialized)?;
            ensure!(
                ann.dimensions() == self.dimensions,
                "ANN dimensions differ from embedding provider"
            );
            ann.reserve_capacity_and_threads(ann.size().max(1), 1)?;
            trace.counter(deserialize_span, "chunks", ann.size() as u64);
            trace.end(deserialize_span, Default::default());
            self.ann_cache = Some((active, ann));
        }
        trace.end(ann_load, Default::default());
        let filter_span = trace.begin("semantic.filter_normalization", parent);
        let folder = options
            .folder
            .as_ref()
            .map(std::fs::canonicalize)
            .transpose()?
            .map(|p| {
                format!(
                    "{}{}",
                    p.to_string_lossy().trim_end_matches(['/', '\\']),
                    std::path::MAIN_SEPARATOR
                )
            });
        let extension = options
            .extension
            .as_ref()
            .map(|ext| ext.trim_start_matches('.').to_ascii_lowercase());
        let min_size = options.min_size.map(i64::try_from).transpose()?;
        let max_size = options.max_size.map(i64::try_from).transpose()?;
        let filter = FilterKey {
            folder,
            extension,
            min_size,
            max_size,
            modified_after: options.modified_after_unix_ms,
            modified_before: options.modified_before_unix_ms,
            min_duration: options.min_duration_ms,
            max_duration: options.max_duration_ms,
            source_type: source_type.map(str::to_owned),
            code_only: options.code_only,
        };
        trace.end(filter_span, Default::default());
        let eligibility_span = trace.begin("semantic.eligibility", parent);
        let (revision, floor): (i64, i64) = snapshot.query_row(
            "SELECT corpus_revision,dirty_floor FROM semantic_meta WHERE singleton=1",
            [],
            |row| Ok((row.get(0)?, row.get(1)?)),
        )?;
        let existing = self.eligibility_cache.take();
        trace.counter(
            eligibility_span,
            "cache_hit",
            u64::from(existing.as_ref().is_some_and(|c| {
                c.generation == active && c.filter == filter && c.revision == revision
            })),
        );
        let mut cache = match existing {
            Some(mut cache)
                if cache.generation == active
                    && cache.filter == filter
                    && cache.revision >= floor =>
            {
                if cache.revision != revision {
                    let mut statement=snapshot.prepare("SELECT path FROM semantic_dirty_paths WHERE revision>?1 AND revision<=?2 ORDER BY path LIMIT 1001")?;
                    let paths = statement
                        .query_map(params![cache.revision, revision], |row| {
                            row.get::<_, String>(0)
                        })?
                        .collect::<rusqlite::Result<Vec<_>>>()?;
                    trace.counter(eligibility_span, "dirty_paths", paths.len() as u64);
                    if paths.len() > 1000 {
                        cache = collect_eligibility_traced(
                            &snapshot,
                            active,
                            revision,
                            &filter,
                            None,
                            trace,
                            eligibility_span,
                        )?;
                    } else {
                        for path in paths {
                            if let Some(old) = cache.by_path.remove(&path) {
                                for key in old {
                                    Arc::make_mut(&mut cache.keys).remove(&key);
                                }
                            }
                            let changed = collect_eligibility_traced(
                                &snapshot,
                                active,
                                revision,
                                &filter,
                                Some(&path),
                                trace,
                                eligibility_span,
                            )?;
                            Arc::make_mut(&mut cache.keys).extend(changed.keys.iter().copied());
                            cache.by_path.extend(changed.by_path);
                        }
                        cache.revision = revision;
                    }
                }
                cache
            }
            _ => collect_eligibility_traced(
                &snapshot,
                active,
                revision,
                &filter,
                None,
                trace,
                eligibility_span,
            )?,
        };
        ensure!(
            cache.keys.len() <= MAX_SCAN_CHUNKS,
            "Eligibility cache exceeds chunk resource budget"
        );
        trace.counter(eligibility_span, "eligible_chunks", cache.keys.len() as u64);
        trace.end(eligibility_span, Default::default());
        cache.revision = revision;
        let eligible = Arc::clone(&cache.keys);
        self.eligibility_cache = Some(cache);
        if eligible.is_empty() {
            return Ok(Vec::new());
        }
        let ann = &self.ann_cache.as_ref().expect("loaded ANN cache").1;
        let mut candidate_count = limit.saturating_mul(4).min(eligible.len()).max(1);
        let mut results;
        let mut filesystem_validity = HashMap::<String, bool>::new();
        let mut passes = 0u64;
        loop {
            passes += 1;
            let pass_span = trace.begin("semantic.ann_pass", parent);
            trace.counter(pass_span, "requested_chunks", candidate_count as u64);
            let ann_span = trace.begin("semantic.ann_search", pass_span);
            let matches =
                ann.filtered_search(query, candidate_count, |key| eligible.contains(&key))?;
            trace.counter(ann_span, "returned_chunks", matches.keys.len() as u64);
            trace.end(ann_span, Default::default());
            let materialization_span = trace.begin("semantic.parent_materialization", pass_span);
            let mut ranked: Vec<_> = matches.keys.into_iter().zip(matches.distances).collect();
            ranked.sort_by(|a, b| a.1.total_cmp(&b.1).then_with(|| a.0.cmp(&b.0)));
            let mut best = HashMap::<String, SearchResult>::new();
            let mut materialize=snapshot.prepare("SELECT c.path,f.filename,c.snippet,c.kind,c.number,c.source_type,c.file_size,c.file_mtime FROM semantic_chunks c JOIN files f ON f.path=c.path WHERE c.rowid=?1 AND c.generation=?2")?;
            for (key, distance) in ranked {
                let cosine = 1.0 - distance;
                ensure!(cosine.is_finite(), "ANN produced nonfinite distance");
                if cosine < MIN_COSINE {
                    continue;
                }
                let (result, size, mtime) =
                    materialize.query_row(params![i64::try_from(key)?, active], |row| {
                        Ok((
                            SearchResult {
                                path: row.get(0)?,
                                filename: row.get(1)?,
                                snippet: row.get(2)?,
                                score: f64::from(cosine),
                                match_kind: match row.get::<_, String>(5)?.as_str() {
                                    "text" => "semantic".into(),
                                    other => format!("semantic_{other}"),
                                },
                                source: Some(SourceLocation {
                                    kind: row.get(3)?,
                                    number: row.get(4)?,
                                }),
                                extraction_error: None,
                            },
                            row.get::<_, Option<i64>>(6)?,
                            row.get::<_, Option<i64>>(7)?,
                        ))
                    })?;
                if let (Some(size), Some(mtime)) = (size, mtime) {
                    let valid = *filesystem_validity
                        .entry(result.path.clone())
                        .or_insert_with(|| {
                            #[cfg(test)]
                            MEDIA_STAT_CALLS.with(|count| count.set(count.get() + 1));
                            let validation_span = trace.begin(
                                "semantic.parent_filesystem_validation",
                                materialization_span,
                            );
                            let valid =
                                std::fs::metadata(&result.path)
                                    .ok()
                                    .is_some_and(|metadata| {
                                        metadata.is_file()
                                            && i64::try_from(metadata.len()).ok() == Some(size)
                                            && metadata
                                                .modified()
                                                .ok()
                                                .and_then(|t| {
                                                    t.duration_since(std::time::UNIX_EPOCH).ok()
                                                })
                                                .and_then(|d| i64::try_from(d.as_nanos()).ok())
                                                == Some(mtime)
                                    });
                            trace.counter(validation_span, "valid", u64::from(valid));
                            trace.end(validation_span, Default::default());
                            valid
                        });
                    if !valid {
                        continue;
                    }
                }
                if best.contains_key(&result.path) {
                    continue;
                }
                best.insert(result.path.clone(), result);
            }
            results = best.into_values().collect::<Vec<_>>();
            trace.counter(materialization_span, "unique_parents", results.len() as u64);
            trace.counter(
                materialization_span,
                "filesystem_checks",
                filesystem_validity.len() as u64,
            );
            trace.end(materialization_span, Default::default());
            trace.end(pass_span, Default::default());
            if results.len() >= limit || candidate_count == eligible.len() {
                break;
            }
            candidate_count = candidate_count.saturating_mul(2).min(eligible.len());
        }
        results.sort_by(|a, b| {
            b.score
                .total_cmp(&a.score)
                .then_with(|| a.path.cmp(&b.path))
        });
        results.truncate(limit);
        trace.counter(parent, "ann_passes", passes);
        trace.counter(parent, "result_files", results.len() as u64);
        trace.counter(
            parent,
            "filesystem_checks",
            filesystem_validity.len() as u64,
        );
        snapshot.commit()?;
        Ok(results)
    }

    #[cfg(test)]
    fn exact_search(
        &self,
        query: &[f32],
        fingerprint: &str,
        limit: usize,
        options: &SearchOptions,
    ) -> Result<Vec<SearchResult>> {
        ensure!(
            query.len() == self.dimensions && query.iter().all(|v| v.is_finite()),
            "Invalid query vector"
        );
        let active: Option<i64> = self.connection.query_row("SELECT g.id FROM semantic_generations g JOIN semantic_meta m ON m.active_generation=g.id WHERE g.fingerprint=?1 AND g.dimensions=?2", params![fingerprint,self.dimensions as i64], |row| row.get(0)).optional()?;
        let Some(active) = active else {
            return Ok(Vec::new());
        };
        let folder = options
            .folder
            .as_ref()
            .map(std::fs::canonicalize)
            .transpose()?
            .map(|p| {
                format!(
                    "{}{}",
                    p.to_string_lossy().trim_end_matches(['/', '\\']),
                    std::path::MAIN_SEPARATOR
                )
            });
        let extension = options
            .extension
            .as_ref()
            .map(|ext| ext.trim_start_matches('.').to_ascii_lowercase());
        let min_size = options.min_size.map(i64::try_from).transpose()?;
        let max_size = options.max_size.map(i64::try_from).transpose()?;
        let mut statement = self.connection.prepare("SELECT c.passage_id,c.path,f.filename,c.snippet,c.vector,c.content_hash,p.text,c.kind,c.number
            FROM semantic_chunks c JOIN passages p ON p.rowid=c.passage_id AND p.file_path=c.path AND p.kind=c.kind AND p.number=c.number
            JOIN files f ON f.path=c.path WHERE c.generation=?1
            AND (?2 IS NULL OR substr(f.path,1,length(?2))=?2)
            AND (?3 IS NULL OR f.extension=?3)
            AND (?4 IS NULL OR f.size>=?4) AND (?5 IS NULL OR f.size<=?5)
            AND (?6 IS NULL OR f.mtime/1000000>=?6) AND (?7 IS NULL OR f.mtime/1000000<=?7)
            ORDER BY c.passage_id,c.ordinal LIMIT ?8")?;
        // Fetch one extra to detect the baseline cap instead of silently hiding
        // candidates. Metadata filtering precedes this cap and all top-k limits.
        let mut rows = statement.query(params![
            active,
            folder,
            extension,
            min_size,
            max_size,
            options.modified_after_unix_ms,
            options.modified_before_unix_ms,
            MAX_SCAN_CHUNKS as i64 + 1
        ])?;
        let mut hashes = HashMap::<i64, String>::new();
        let mut best = HashMap::<String, SearchResult>::new();
        let mut scanned = 0;
        while let Some(row) = rows.next()? {
            scanned += 1;
            ensure!(
                scanned <= MAX_SCAN_CHUNKS,
                "Exact-vector baseline exceeds {MAX_SCAN_CHUNKS} chunks; ANN integration required"
            );
            let passage_id: i64 = row.get(0)?;
            let current_hash = if let Some(hash) = hashes.get(&passage_id) {
                hash.clone()
            } else {
                let hash = content_hash(&row.get::<_, String>(6)?);
                hashes.insert(passage_id, hash.clone());
                hash
            };
            if current_hash != row.get::<_, String>(5)? {
                continue;
            }
            let bytes: Vec<u8> = row.get(4)?;
            ensure!(
                bytes.len() == self.dimensions * 4,
                "Corrupt stored embedding length"
            );
            let mut cosine = 0.0;
            for (dimension, value) in bytes.as_chunks::<4>().0.iter().enumerate() {
                let value = f32::from_le_bytes(*value);
                ensure!(value.is_finite(), "Corrupt stored embedding value");
                cosine += value * query[dimension];
            }
            if cosine < MIN_COSINE {
                continue;
            }
            let path: String = row.get(1)?;
            if best
                .get(&path)
                .is_some_and(|result| result.score >= f64::from(cosine))
            {
                continue;
            }
            best.insert(
                path.clone(),
                SearchResult {
                    path,
                    filename: row.get(2)?,
                    snippet: row.get(3)?,
                    score: f64::from(cosine),
                    match_kind: "semantic".into(),
                    source: Some(SourceLocation {
                        kind: row.get(7)?,
                        number: row.get(8)?,
                    }),
                    extraction_error: None,
                },
            );
        }
        let mut results: Vec<_> = best.into_values().collect();
        results.sort_by(|a, b| {
            b.score
                .total_cmp(&a.score)
                .then_with(|| a.path.cmp(&b.path))
        });
        results.truncate(limit);
        Ok(results)
    }
}

#[allow(clippy::too_many_arguments)]
fn collect_eligibility_traced(
    connection: &Connection,
    generation: i64,
    revision: i64,
    filter: &FilterKey,
    path: Option<&str>,
    trace: &mut TraceCollector,
    parent: Option<SpanToken>,
) -> Result<EligibilityCache> {
    trace.timed(
        "semantic.eligibility_filtered_scan_and_hash",
        parent,
        |trace, span| {
            let result = collect_eligibility(connection, generation, revision, filter, path);
            if let Ok(cache) = &result {
                trace.counter(span, "eligible_chunks", cache.keys.len() as u64);
            }
            trace.counter(span, "single_dirty_file", u64::from(path.is_some()));
            result
        },
    )
}

fn collect_eligibility(
    connection: &Connection,
    generation: i64,
    revision: i64,
    filter: &FilterKey,
    path: Option<&str>,
) -> Result<EligibilityCache> {
    let code = if filter.code_only {
        format!(" AND {}", searchi_core::code_file_predicate())
    } else {
        String::new()
    };
    let mut statement=connection.prepare(&format!("SELECT c.rowid,c.passage_id,c.content_hash,p.text,c.path,c.source_type FROM semantic_chunks c
        LEFT JOIN passages p ON c.source_type='text' AND p.rowid=c.passage_id AND p.file_path=c.path AND p.kind=c.kind AND p.number=c.number
        JOIN files f ON f.path=c.path WHERE c.generation=?1 AND ((c.source_type='text' AND p.rowid IS NOT NULL) OR (c.source_type!='text' AND c.file_size=f.size AND c.file_mtime=f.mtime))
        AND (?2 IS NULL OR substr(f.path,1,length(?2))=?2) AND (?3 IS NULL OR f.extension=?3)
        AND (?4 IS NULL OR f.size>=?4) AND (?5 IS NULL OR f.size<=?5)
        AND (?6 IS NULL OR f.mtime/1000000>=?6) AND (?7 IS NULL OR f.mtime/1000000<=?7)
        AND (?10 IS NULL OR EXISTS(SELECT 1 FROM media_metadata m WHERE m.path=f.path AND m.duration_ms>=?10))
        AND (?11 IS NULL OR EXISTS(SELECT 1 FROM media_metadata m WHERE m.path=f.path AND m.duration_ms<=?11))
        AND (?12 IS NULL OR c.source_type=?12)
        AND (?9 IS NULL OR c.path=?9) {code} ORDER BY c.passage_id,c.ordinal LIMIT ?8"))?;
    let mut rows = statement.query(params![
        generation,
        filter.folder,
        filter.extension,
        filter.min_size,
        filter.max_size,
        filter.modified_after,
        filter.modified_before,
        MAX_SCAN_CHUNKS as i64 + 1,
        path,
        filter.min_duration,
        filter.max_duration,
        filter.source_type
    ])?;
    let mut hashes = HashMap::<i64, String>::new();
    let mut keys = HashSet::new();
    let mut by_path = HashMap::<String, Vec<u64>>::new();
    let mut count = 0;
    while let Some(row) = rows.next()? {
        count += 1;
        ensure!(
            count <= MAX_SCAN_CHUNKS,
            "Corpus exceeds {MAX_SCAN_CHUNKS} chunk resource budget"
        );
        let passage_id: i64 = row.get(1)?;
        let hash = if row.get::<_, String>(5)? != "text" {
            row.get::<_, String>(2)?
        } else if let Some(hash) = hashes.get(&passage_id) {
            hash.clone()
        } else {
            let hash = content_hash(&row.get::<_, String>(3)?);
            hashes.insert(passage_id, hash.clone());
            hash
        };
        if hash == row.get::<_, String>(2)? {
            let key = u64::try_from(row.get::<_, i64>(0)?)?;
            keys.insert(key);
            by_path.entry(row.get(4)?).or_default().push(key);
        }
    }
    Ok(EligibilityCache {
        generation,
        revision,
        filter: filter.clone(),
        keys: Arc::new(keys),
        by_path,
    })
}

#[cfg(test)]
mod tests {
    use super::*;
    use searchi_core::SearchIndex;
    const DIMENSIONS: usize = 768;

    #[test]
    fn code_filter_precedes_ann_top_k_and_cache_distinguishes_scope() -> Result<()> {
        // Retrieval geometry only: production vectors come from Google.
        let directory = tempfile::tempdir()?;
        let root = directory.path().join("sources");
        std::fs::create_dir(&root)?;
        for n in 0..40 {
            std::fs::write(
                root.join(format!("document-{n}.md")),
                "parse JSON and retry requests",
            )?;
        }
        std::fs::write(
            root.join("network.rs"),
            "fn retry_request() { parse_json(); }",
        )?;
        std::fs::write(root.join("Makefile"), "build: compile_sources\n")?;
        let db = directory.path().join("index.db");
        let mut lexical = SearchIndex::open(&db)?;
        lexical.index_folder(&root)?;
        let mut store = Store::open(&db, DIMENSIONS)?;
        let generation = store.begin("code-filter-proof")?;
        let mut query = vec![0.; DIMENSIONS];
        query[0] = 1.;
        let mut weaker = query.clone();
        weaker[0] = 0.9;
        weaker[1] = (1.0_f32 - 0.9_f32.powi(2)).sqrt();
        for passage in lexical.passage_batch(0, 100)? {
            let vector = if searchi_core::is_code_path(Path::new(&passage.path)) {
                weaker.clone()
            } else {
                query.clone()
            };
            let window = TextWindow {
                text: passage.text.clone(),
                start_byte: 0,
                end_byte: passage.text.len(),
            };
            store.insert(generation, &passage, 0, &[window], &[vector])?;
        }
        store.activate(generation)?;
        assert!(
            store.search(&query, "code-filter-proof", 1, &SearchOptions::default())?[0]
                .filename
                .ends_with(".md")
        );
        let code = SearchOptions {
            code_only: true,
            ..Default::default()
        };
        let hits = store.search(&query, "code-filter-proof", 2, &code)?;
        assert_eq!(hits.len(), 2);
        assert!(hits
            .iter()
            .all(|h| searchi_core::is_code_path(Path::new(&h.path))));
        let incompatible = SearchOptions {
            code_only: true,
            extension: Some("md".into()),
            ..Default::default()
        };
        assert!(store
            .search(&query, "code-filter-proof", 2, &incompatible)?
            .is_empty());
        std::fs::remove_file(root.join("network.rs"))?;
        lexical.index_folder(&root)?;
        assert_eq!(
            store.search(&query, "code-filter-proof", 2, &code)?.len(),
            1
        );
        Ok(())
    }

    #[test]
    fn many_video_windows_do_not_crowd_out_other_parent_files() -> Result<()> {
        // Geometry verifies grouped retrieval, not model inference or codecs.
        let directory = tempfile::tempdir()?;
        let root = directory.path().join("media");
        std::fs::create_dir(&root)?;
        for name in ["long.mp4", "other.mp4", "excluded.png"] {
            std::fs::write(root.join(name), b"parent-grouping identity fixture")?;
        }
        let db = directory.path().join("index.db");
        let mut lexical = SearchIndex::open(&db)?;
        lexical.index_folder(&root)?;
        let mut store = Store::open(&db, DIMENSIONS)?;
        let generation = store.begin("grouped-retrieval-proof")?;
        let mut query = vec![0.; DIMENSIONS];
        query[0] = 1.;
        let mut second = query.clone();
        second[0] = 0.95;
        second[1] = (1.0_f32 - 0.95_f32.powi(2)).sqrt();
        for (id, path, _, _) in store.media_batch(0)? {
            let identity = searchi_media::MediaIdentity::read(Path::new(&path), 1024)?;
            if path.ends_with("long.mp4") {
                for ordinal in 0..96 {
                    store.insert_media(
                        generation,
                        id,
                        ordinal,
                        &identity,
                        "video",
                        ordinal as u32 * 2000,
                        &query,
                    )?;
                }
            } else if path.ends_with("other.mp4") {
                store.insert_media(generation, id, 0, &identity, "video", 4000, &second)?;
            } else {
                store.insert_media(generation, id, 0, &identity, "image", 0, &query)?;
            }
        }
        store.activate(generation)?;
        let options = SearchOptions {
            extension: Some("mp4".into()),
            ..Default::default()
        };
        MEDIA_STAT_CALLS.with(|count| count.set(0));
        let mut trace = TraceCollector::new(MetricsMode::Debug);
        let results = store.search_origin_traced(
            &query,
            "grouped-retrieval-proof",
            2,
            &options,
            None,
            &mut trace,
            None,
        )?;
        assert_eq!(results.len(), 2);
        assert!(results[0].path.ends_with("long.mp4"));
        assert!(results[1].path.ends_with("other.mp4"));
        assert_eq!(results[1].source.as_ref().unwrap().number, 4000);
        assert_eq!(
            MEDIA_STAT_CALLS.with(std::cell::Cell::get),
            2,
            "Each parent is stat-checked once despite repeated ANN expansions"
        );
        let metrics = trace.finish(results.len());
        let spans = metrics.trace.unwrap();
        assert!(
            spans
                .iter()
                .filter(|s| s.name == "semantic.ann_pass")
                .count()
                > 1
        );
        assert_eq!(
            spans
                .iter()
                .filter(|s| s.name == "semantic.parent_filesystem_validation")
                .count(),
            2
        );
        assert!(
            spans
                .iter()
                .find(|s| s.name == "semantic.retrieval")
                .unwrap()
                .counters["ann_passes"]
                > 1
        );
        for span in &spans {
            if let Some(parent) = span.parent {
                let parent = &spans[parent];
                assert!(span.start_ms >= parent.start_ms);
                assert!(
                    span.start_ms + span.duration_ms <= parent.start_ms + parent.duration_ms + 1e-6
                );
            }
        }
        Ok(())
    }

    #[test]
    fn media_origins_persist_filters_and_changes_remove_stale_candidates() -> Result<()> {
        let directory = tempfile::tempdir()?;
        let root = directory.path().join("media");
        std::fs::create_dir(&root)?;
        let file = root.join("clip.mp4");
        std::fs::write(&file, b"storage identity fixture; not an inference test")?;
        let db = directory.path().join("index.db");
        let mut lexical = SearchIndex::open(&db)?;
        lexical.index_folder(&root)?;
        let mut store = Store::open(&db, DIMENSIONS)?;
        let (id, path, _, _) = store.media_batch(0)?.remove(0);
        let identity = searchi_media::MediaIdentity::read(Path::new(&path), 1024)?;
        lexical.set_media_metadata(
            &path,
            "artist: real extracted metadata fixture",
            65000,
            identity.bytes,
            identity.modified_ns,
        )?;
        let mut vector = vec![0.; DIMENSIONS];
        vector[0] = 1.;
        let generation = store.begin("media-storage-proof")?;
        store.insert_media(generation, id, 0, &identity, "video", 2345, &vector)?;
        store.insert_media(generation, id, 1, &identity, "audio", 28000, &vector)?;
        store.activate(generation)?;
        drop(store);
        let mut store = Store::open(&db, DIMENSIONS)?;
        let mut cold = TraceCollector::new(MetricsMode::Debug);
        let results = store.search_origin_traced(
            &vector,
            "media-storage-proof",
            5,
            &SearchOptions::default(),
            None,
            &mut cold,
            None,
        )?;
        let cold = cold.finish(results.len()).trace.unwrap();
        assert_eq!(
            cold.iter()
                .find(|s| s.name == "semantic.ann_load")
                .unwrap()
                .counters["cache_hit"],
            0
        );
        assert!(cold.iter().any(|s| s.name == "semantic.ann_checksum"));
        let mut warm = TraceCollector::new(MetricsMode::Debug);
        let warm_results = store.search_origin_traced(
            &vector,
            "media-storage-proof",
            5,
            &SearchOptions::default(),
            None,
            &mut warm,
            None,
        )?;
        assert_eq!(
            serde_json::to_value(&results)?,
            serde_json::to_value(&warm_results)?
        );
        let warm = warm.finish(warm_results.len()).trace.unwrap();
        assert_eq!(
            warm.iter()
                .find(|s| s.name == "semantic.ann_load")
                .unwrap()
                .counters["cache_hit"],
            1
        );
        assert_eq!(
            warm.iter()
                .find(|s| s.name == "semantic.eligibility")
                .unwrap()
                .counters["cache_hit"],
            1
        );
        assert!(!warm.iter().any(|s| s.name == "semantic.ann_blob_read"));
        assert_eq!(results.len(), 1);
        assert_eq!(results[0].source.as_ref().unwrap().kind, "timestamp_ms");
        assert!([2345, 28000].contains(&results[0].source.as_ref().unwrap().number));
        let audio = store.search_origin(
            &vector,
            "media-storage-proof",
            5,
            &SearchOptions::default(),
            Some("audio"),
        )?;
        assert_eq!(audio.len(), 1);
        assert_eq!(audio[0].match_kind, "semantic_audio");
        assert_eq!(audio[0].source.as_ref().unwrap().number, 28000);
        let video = store.search_origin(
            &vector,
            "media-storage-proof",
            5,
            &SearchOptions::default(),
            Some("video"),
        )?;
        assert_eq!(video.len(), 1);
        assert_eq!(video[0].match_kind, "semantic_video");
        assert_eq!(video[0].source.as_ref().unwrap().number, 2345);
        assert!(store
            .search_origin(
                &vector,
                "media-storage-proof",
                5,
                &SearchOptions::default(),
                Some("image")
            )?
            .is_empty());
        assert!(
            results[0].match_kind == "semantic_video" || results[0].match_kind == "semantic_audio"
        );
        let filter = SearchOptions {
            extension: Some("png".into()),
            ..SearchOptions::default()
        };
        assert!(store
            .search(&vector, "media-storage-proof", 5, &filter)?
            .is_empty());
        let duration_filter = SearchOptions {
            min_duration_ms: Some(66000),
            ..Default::default()
        };
        assert!(store
            .search(&vector, "media-storage-proof", 5, &duration_filter)?
            .is_empty());
        let duration_filter = SearchOptions {
            min_duration_ms: Some(64000),
            max_duration_ms: Some(66000),
            ..Default::default()
        };
        assert_eq!(
            store
                .search(&vector, "media-storage-proof", 5, &duration_filter)?
                .len(),
            1
        );
        std::fs::write(&file, b"changed")?;
        // Foreground hits check only actual candidate metadata, before watcher
        // reconciliation; they never rehash the complete filesystem corpus.
        assert!(store
            .search(&vector, "media-storage-proof", 5, &SearchOptions::default())?
            .is_empty());
        lexical.index_folder(&root)?;
        assert!(store
            .search(&vector, "media-storage-proof", 5, &SearchOptions::default())?
            .is_empty());
        assert!(store
            .insert_media(generation, id, 2, &identity, "video", 0, &vector)
            .is_err());
        std::fs::remove_file(&file)?;
        lexical.index_folder(&root)?;
        assert!(store
            .search(&vector, "media-storage-proof", 5, &SearchOptions::default())?
            .is_empty());
        Ok(())
    }

    #[test]
    fn media_failure_removes_partial_vectors_and_persists_reason() -> Result<()> {
        let directory = tempfile::tempdir()?;
        let file = directory.path().join("picture.png");
        std::fs::write(&file, b"identity fixture")?;
        let db = directory.path().join("index.db");
        let mut lexical = SearchIndex::open(&db)?;
        lexical.index_folder(directory.path())?;
        let mut store = Store::open(&db, DIMENSIONS)?;
        let (id, path, _, _) = store
            .media_batch(0)?
            .into_iter()
            .find(|(_, p, _, _)| p.ends_with("picture.png"))
            .unwrap();
        let identity = searchi_media::MediaIdentity::read(Path::new(&path), 1024)?;
        let mut vector = vec![0.; DIMENSIONS];
        vector[0] = 1.;
        let generation = store.begin("failure-proof")?;
        store.insert_media(generation, id, 0, &identity, "image", 0, &vector)?;
        store.media_failure(generation, &path, "Decoder rejected corrupt image")?;
        let chunks: usize = store.connection.query_row(
            "SELECT count(*) FROM semantic_chunks WHERE generation=?1",
            [generation],
            |r| r.get(0),
        )?;
        assert_eq!(chunks, 0);
        let reason: String = store.connection.query_row(
            "SELECT message FROM semantic_media_errors WHERE generation=?1",
            [generation],
            |r| r.get(0),
        )?;
        assert!(reason.contains("corrupt"));
        Ok(())
    }

    #[test]
    fn deleted_media_without_reconciliation_does_not_hide_later_valid_top_k() -> Result<()> {
        let directory = tempfile::tempdir()?;
        let root = directory.path().join("images");
        std::fs::create_dir(&root)?;
        for name in ["a.png", "b.png"] {
            std::fs::write(root.join(name), b"storage fixture")?;
        }
        let db = directory.path().join("index.db");
        let mut lexical = SearchIndex::open(&db)?;
        lexical.index_folder(&root)?;
        let mut store = Store::open(&db, DIMENSIONS)?;
        let generation = store.begin("candidate-stat-proof")?;
        let mut vector = vec![0.; DIMENSIONS];
        vector[0] = 1.;
        for (id, path, _, _) in store.media_batch(0)? {
            let identity = searchi_media::MediaIdentity::read(Path::new(&path), 1024)?;
            store.insert_media(generation, id, 0, &identity, "image", 0, &vector)?;
        }
        store.activate(generation)?;
        std::fs::remove_file(root.join("a.png"))?;
        let results = store.search(
            &vector,
            "candidate-stat-proof",
            1,
            &SearchOptions::default(),
        )?;
        assert_eq!(results.len(), 1);
        assert!(results[0].path.ends_with("b.png"));
        std::fs::remove_file(root.join("b.png"))?;
        assert!(store
            .search(
                &vector,
                "candidate-stat-proof",
                1,
                &SearchOptions::default()
            )?
            .is_empty());
        Ok(())
    }

    #[test]
    fn generation_persists_failed_staging_preserves_active_and_changes_hide_stale_vectors(
    ) -> Result<()> {
        let directory = tempfile::tempdir()?;
        let root = directory.path().join("docs");
        std::fs::create_dir(&root)?;
        let db = directory.path().join("index.db");
        std::fs::write(root.join("notes.txt"), "original relevant content")?;
        let mut index = SearchIndex::open(&db)?;
        index.index_folder(&root)?;
        let passage = index.passage_batch(0, 1)?.remove(0);
        let mut vector = vec![0.0; DIMENSIONS];
        vector[0] = 1.0;
        let windows = [TextWindow {
            text: passage.text.clone(),
            start_byte: 0,
            end_byte: passage.text.len(),
        }];
        let mut store = Store::open(&db, DIMENSIONS)?;
        let generation = store.begin("test-storage-vectors")?;
        store.insert(generation, &passage, 0, &windows, &[vector.clone()])?;
        store.activate(generation)?;
        assert_eq!(
            store.exact_search(
                &vector,
                "test-storage-vectors",
                10,
                &SearchOptions::default()
            )?[0]
                .path,
            store.search(
                &vector,
                "test-storage-vectors",
                10,
                &SearchOptions::default()
            )?[0]
                .path
        );
        drop(store);
        let mut store = Store::open(&db, DIMENSIONS)?;
        assert_eq!(
            store
                .search(
                    &vector,
                    "test-storage-vectors",
                    10,
                    &SearchOptions::default()
                )?
                .len(),
            1
        );
        assert!(store
            .search(&vector, "different-model", 10, &SearchOptions::default())?
            .is_empty());
        let staging = store.begin("new-model")?;
        assert_eq!(
            store
                .search(
                    &vector,
                    "test-storage-vectors",
                    10,
                    &SearchOptions::default()
                )?
                .len(),
            1
        );
        store.abandon(staging)?;
        std::fs::write(
            root.join("notes.txt"),
            "replacement unrelated content longer than before",
        )?;
        index.index_folder(&root)?;
        assert!(store
            .search(
                &vector,
                "test-storage-vectors",
                10,
                &SearchOptions::default()
            )?
            .is_empty());
        std::fs::remove_file(root.join("notes.txt"))?;
        index.index_folder(&root)?;
        assert!(store
            .search(
                &vector,
                "test-storage-vectors",
                10,
                &SearchOptions::default()
            )?
            .is_empty());
        Ok(())
    }

    #[test]
    fn ann_filters_before_top_k_checks_checksum_and_status_tracks_corpus_changes() -> Result<()> {
        let directory = tempfile::tempdir()?;
        let root = directory.path().join("docs");
        std::fs::create_dir(&root)?;
        let db = directory.path().join("index.db");
        std::fs::write(root.join("closest.md"), "closest metadata excluded source")?;
        std::fs::write(root.join("allowed.txt"), "allowed metadata source")?;
        let mut lexical = SearchIndex::open(&db)?;
        lexical.index_folder(&root)?;
        let passages = lexical.passage_batch(0, 10)?;
        let mut store = Store::open(&db, DIMENSIONS)?;
        let fingerprint = crate::generation_fingerprint(searchi_semantic::GEMMA_FINGERPRINT);
        let generation = store.begin(&fingerprint)?;
        let mut query = vec![0.0; DIMENSIONS];
        query[0] = 1.0;
        for passage in &passages {
            let mut vector = query.clone();
            if passage.filename == "allowed.txt" {
                vector[0] = 0.8;
                vector[1] = 0.6;
            }
            let windows = [TextWindow {
                text: passage.text.clone(),
                start_byte: 0,
                end_byte: passage.text.len(),
            }];
            store.insert(generation, passage, 0, &windows, &[vector])?;
        }
        store.activate(generation)?;
        let options = SearchOptions {
            extension: Some("txt".into()),
            ..Default::default()
        };
        assert_eq!(
            store.search(&query, &fingerprint, 1, &options)?[0].filename,
            "allowed.txt"
        );
        let warmed_hashes = HASH_CALLS.with(std::cell::Cell::get);
        let _ = store.search(&query, &fingerprint, 1, &options)?;
        assert_eq!(
            HASH_CALLS.with(std::cell::Cell::get),
            warmed_hashes,
            "Warm query rehashed unchanged corpus"
        );
        assert_eq!(
            store.exact_search(&query, &fingerprint, 1, &options)?[0].filename,
            "allowed.txt"
        );
        assert!(!crate::HybridSearch::embedding_status(&db)?.stale);
        std::fs::write(
            root.join("allowed.txt"),
            "replacement changes the generation revision",
        )?;
        lexical.index_folder(&root)?;
        let status = crate::HybridSearch::embedding_status(&db)?;
        let before_delta = HASH_CALLS.with(std::cell::Cell::get);
        assert!(store.search(&query, &fingerprint, 1, &options)?.is_empty());
        assert!(
            HASH_CALLS.with(std::cell::Cell::get) - before_delta <= 1,
            "Single file change rehashed unrelated passages"
        );
        assert!(status.stale);
        assert_eq!(status.pending, 2);
        store.connection.execute(
            "UPDATE semantic_generations SET ann_blob=x'010203' WHERE id=?1",
            [generation],
        )?;
        drop(store);
        let mut store = Store::open(&db, DIMENSIONS)?;
        assert!(store
            .search(&query, &fingerprint, 1, &SearchOptions::default())
            .unwrap_err()
            .to_string()
            .contains("SHA256 mismatch"));
        Ok(())
    }
}

#[cfg(test)]
#[path = "ann_benchmark.rs"]
mod ann_benchmark;