chaotic_semantic_memory 0.3.6

//! ANN index persistence operations.
//!
//! Extracted from persistence.rs to satisfy the 500 LOC gate.

use crate::error::{MemoryError, Result};
use crate::persistence::Persistence;
use libsql::params;

impl Persistence {
    /// Save the serialized index state to the database.
    pub async fn save_index(&self, ns: &str, id: &str, data: &[u8]) -> Result<()> {
        let _permit = self.acquire_remote_slot().await?;
        let conn = self.connect().await?;
        conn.execute(
            "INSERT OR REPLACE INTO csm_hnsw_graph (namespace, id, data, modified_at)
             VALUES (?1, ?2, ?3, ?4)",
            params![
                ns.to_string(),
                id,
                data,
                crate::singularity::unix_now_secs() as i64
            ],
        )
        .await
        .map_err(|e| MemoryError::database(format!("Failed to save index: {}", e)))?;
        Ok(())
    }

    /// Load the serialized index state from the database.
    pub async fn load_index(&self, ns: &str, id: &str) -> Result<Option<Vec<u8>>> {
        let _permit = self.acquire_remote_slot().await?;
        let conn = self.connect().await?;
        let mut rows = conn
            .query(
                "SELECT data FROM csm_hnsw_graph WHERE namespace = ?1 AND id = ?2",
                params![ns.to_string(), id],
            )
            .await
            .map_err(|e| MemoryError::database(format!("Failed to load index: {}", e)))?;

        if let Some(row) = rows
            .next()
            .await
            .map_err(|e| MemoryError::database(format!("Failed to fetch index row: {}", e)))?
        {
            let data: Vec<u8> = row
                .get(0)
                .map_err(|e| MemoryError::database(format!("Failed to get index data: {}", e)))?;
            Ok(Some(data))
        } else {
            Ok(None)
        }
    }
}