package fleet

import (
	"database/sql"

	"github.com/google/uuid"
)

func (s *Store) InsertSeerEvent(hostID, eventType, payload string) error {
	_, err := s.db.Exec(`
		INSERT INTO seer_events (id, host_id, event_type, payload_json)
		VALUES (?, ?, ?, ?)
	`, uuid.NewString(), nullString(hostID), eventType, payload)
	return err
}

func (s *Store) ListSeerEvents(limit int) ([]SeerEvent, error) {
	if limit <= 0 {
		limit = 50
	}
	rows, err := s.db.Query(`
		SELECT id, host_id, event_type, payload_json, created_at
		FROM seer_events ORDER BY created_at DESC LIMIT ?
	`, limit)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var events []SeerEvent
	for rows.Next() {
		var e SeerEvent
		var hostID sql.NullString
		if err := rows.Scan(&e.ID, &hostID, &e.EventType, &e.PayloadJSON, &e.CreatedAt); err != nil {
			return nil, err
		}
		if hostID.Valid {
			e.HostID = hostID.String
		}
		events = append(events, e)
	}
	return events, rows.Err()
}

// SeerEvent is a court/LOTL timeline entry.
type SeerEvent struct {
	ID          string `json:"id"`
	HostID      string `json:"host_id,omitempty"`
	EventType   string `json:"event_type"`
	PayloadJSON string `json:"payload_json"`
	CreatedAt   string `json:"created_at"`
}

// ListSeerEventsSince returns events newer than the given SQLite timestamp string (exclusive).
func (s *Store) ListSeerEventsSince(since string, limit int) ([]SeerEvent, error) {
	if limit <= 0 {
		limit = 50
	}
	var rows interface {
		Close() error
		Next() bool
		Scan(dest ...any) error
		Err() error
	}
	var err error
	if since == "" {
		rows, err = s.db.Query(`
			SELECT id, host_id, event_type, payload_json, created_at
			FROM seer_events ORDER BY created_at ASC LIMIT ?`, limit)
	} else {
		rows, err = s.db.Query(`
			SELECT id, host_id, event_type, payload_json, created_at
			FROM seer_events WHERE created_at > ? ORDER BY created_at ASC LIMIT ?`, since, limit)
	}
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var events []SeerEvent
	for rows.Next() {
		var e SeerEvent
		var hostID sql.NullString
		if err := rows.Scan(&e.ID, &hostID, &e.EventType, &e.PayloadJSON, &e.CreatedAt); err != nil {
			return nil, err
		}
		if hostID.Valid {
			e.HostID = hostID.String
		}
		events = append(events, e)
	}
	return events, rows.Err()
}

func nullString(s string) sql.NullString {
	if s == "" {
		return sql.NullString{}
	}
	return sql.NullString{String: s, Valid: true}
}