package store

import "context"

type Endpoint struct {
	ID        int64  `json:"id"`
	RoleLabel string `json:"role_label"`
	Host      string `json:"host"`
	Port      int    `json:"port"`
	TLSMode   string `json:"tls_mode"`
}

func (s *Store) CreateEndpoint(ctx context.Context, e Endpoint) (int64, error) {
	var id int64
	err := s.Pool.QueryRow(ctx,
		`INSERT INTO endpoints (role_label, host, port, tls_mode)
		 VALUES ($1,$2,$3,$4) RETURNING id`,
		e.RoleLabel, e.Host, e.Port, e.TLSMode).Scan(&id)
	return id, err
}

func (s *Store) UpdateEndpoint(ctx context.Context, e Endpoint) error {
	_, err := s.Pool.Exec(ctx,
		`UPDATE endpoints SET role_label=$2, host=$3, port=$4, tls_mode=$5 WHERE id=$1`,
		e.ID, e.RoleLabel, e.Host, e.Port, e.TLSMode)
	return err
}

// CountTasksUsingEndpoint reports how many tasks reference the endpoint on
// either side, so a delete can be refused with a meaningful message instead of
// surfacing a raw foreign-key violation.
func (s *Store) CountTasksUsingEndpoint(ctx context.Context, id int64) (int, error) {
	var n int
	err := s.Pool.QueryRow(ctx,
		`SELECT count(*) FROM tasks WHERE src_endpoint_id=$1 OR dst_endpoint_id=$1`, id).Scan(&n)
	return n, err
}

// DeleteEndpoint removes an endpoint. Tasks reference endpoints without ON
// DELETE CASCADE, so Postgres rejects the delete while any task still uses it.
func (s *Store) DeleteEndpoint(ctx context.Context, id int64) error {
	_, err := s.Pool.Exec(ctx, `DELETE FROM endpoints WHERE id=$1`, id)
	return err
}

func (s *Store) GetEndpoint(ctx context.Context, id int64) (Endpoint, error) {
	var e Endpoint
	err := s.Pool.QueryRow(ctx,
		`SELECT id, role_label, host, port, tls_mode FROM endpoints WHERE id=$1`, id).
		Scan(&e.ID, &e.RoleLabel, &e.Host, &e.Port, &e.TLSMode)
	return e, err
}

func (s *Store) ListEndpoints(ctx context.Context) ([]Endpoint, error) {
	rows, err := s.Pool.Query(ctx,
		`SELECT id, role_label, host, port, tls_mode FROM endpoints ORDER BY id`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	out := []Endpoint{}
	for rows.Next() {
		var e Endpoint
		if err := rows.Scan(&e.ID, &e.RoleLabel, &e.Host, &e.Port, &e.TLSMode); err != nil {
			return nil, err
		}
		out = append(out, e)
	}
	return out, rows.Err()
}