impl Db {
    pub fn add_ha_reading_if_due(&self, reading: &HaReading, min_interval_seconds: i64) -> Result<bool> {
        let cutoff = reading.timestamp.clone() - Duration::seconds(min_interval_seconds.max(1));
        let conn = self.lock()?;
        let changed = conn.execute(
            queries::INSERT_HA_READING_IF_DUE,
            params![
                reading.entity_id,
                reading.zone_id,
                reading.kind,
                reading.timestamp.to_rfc3339(),
                reading.temperature,
                cutoff.to_rfc3339(),
            ],
        )?;
        Ok(changed > 0)
    }

    pub fn list_ha_history(&self, entity_id: Option<&str>, since: DateTime<Utc>, bucket_seconds: i64, limit: u32) -> Result<Vec<HaReading>> {
        let conn = self.lock()?;
        let bucket_seconds = bucket_seconds.max(1);
        let limit = limit.clamp(1, 20_000) as i64;
        let mut rows_out = Vec::new();
        if let Some(entity_id) = entity_id {
            let mut stmt = conn.prepare(queries::LIST_HA_HISTORY_BY_ENTITY_BUCKETED)?;
            let rows = stmt.query_map(params![entity_id, since.to_rfc3339(), bucket_seconds, limit], Self::map_ha_reading)?;
            for row in rows { rows_out.push(row?); }
        } else {
            let mut stmt = conn.prepare(queries::LIST_HA_HISTORY_ALL_BUCKETED)?;
            let rows = stmt.query_map(params![since.to_rfc3339(), bucket_seconds, limit], Self::map_ha_reading)?;
            for row in rows { rows_out.push(row?); }
        }
        Ok(rows_out)
    }

    fn map_ha_reading(row: &rusqlite::Row<'_>) -> rusqlite::Result<HaReading> {
        let timestamp: String = row.get(4)?;
        Ok(HaReading {
            id: row.get(0)?,
            entity_id: row.get(1)?,
            zone_id: row.get(2)?,
            kind: row.get(3)?,
            timestamp: DateTime::parse_from_rfc3339(&timestamp)
                .map(|value| value.with_timezone(&Utc))
                .unwrap_or_else(|_| Utc::now()),
            temperature: row.get(5)?,
        })
    }

}