use std::time::Duration;

use crate::AppState;

/// Background job: age retention + hard SQLite size cap (default 10 GiB).
pub fn spawn(state: AppState) {
    tokio::spawn(async move {
        // Run once shortly after boot, then on the configured cadence.
        tokio::time::sleep(Duration::from_secs(15)).await;
        run_once(&state);

        let secs = state.config.cleanup_interval_secs.max(60);
        let mut ticker = tokio::time::interval(Duration::from_secs(secs));
        ticker.set_missed_tick_behavior(tokio::time::MissedTickBehavior::Skip);
        // Skip the immediate first tick (already ran above).
        ticker.tick().await;

        loop {
            ticker.tick().await;
            run_once(&state);
        }
    });
}

fn run_once(state: &AppState) {
    let max = state.config.max_db_bytes;
    // Aim for 90% of the cap so we don't thrash at the ceiling.
    let target = (max as f64 * 0.90) as u64;
    match state
        .db
        .run_cleanup(state.config.retention_days, max, target)
    {
        Ok(report) => {
            tracing::info!(
                deleted_by_age = report.deleted_by_age,
                deleted_by_size = report.deleted_by_size,
                vacuumed = report.vacuumed,
                bytes_before = report.bytes_before,
                bytes_after = report.bytes_after,
                rows = report.rows_after,
                max_bytes = max,
                "sqlite cleanup finished"
            );
        }
        Err(e) => tracing::warn!(error = %e, "sqlite cleanup failed"),
    }

    match state.db.get_settings() {
        Ok(settings) if settings.cleanup_logs_older_than_3_months => {
            match state
                .db
                .prune_health_results_older_than(crate::settings::HEALTH_LOG_RETENTION_DAYS)
            {
                Ok(n) if n > 0 => {
                    tracing::info!(deleted = n, "pruned health logs older than 3 months")
                }
                Ok(_) => {}
                Err(e) => tracing::warn!(error = %e, "health log prune failed"),
            }
        }
        Ok(_) => {}
        Err(e) => tracing::warn!(error = %e, "load settings for cleanup failed"),
    }
}