package db

import "time"

// MaxSpreadGeneration returns the highest spread_generation among agents (policy genesis version).
func (d *Database) MaxSpreadGeneration() (int, error) {
	if d == nil {
		return 0, nil
	}
	var max int
	err := d.QueryRow(`SELECT COALESCE(MAX(spread_generation), 0) FROM agents`).Scan(&max)
	return max, err
}

// ListPausedSubnetPrefixes returns /24 prefixes currently under immune spread pause.
func (d *Database) ListPausedSubnetPrefixes() ([]string, error) {
	if d == nil {
		return nil, nil
	}
	if err := d.ensureSubnetSpreadPauseTable(); err != nil {
		return nil, err
	}
	rows, err := d.Query(`SELECT prefix FROM subnet_spread_pause WHERE paused_until IS NOT NULL AND paused_until > ?`, time.Now().UTC())
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	var out []string
	for rows.Next() {
		var p string
		if err := rows.Scan(&p); err != nil {
			return nil, err
		}
		if p = normalizeSubnetPrefix(p); p != "" {
			out = append(out, p)
		}
	}
	return out, rows.Err()
}