package aggregate

import (
	"strings"

	"github.com/pingcap-inc/clinic/pkg/ngm/statements/api"
	"github.com/pingcap-inc/clinic/pkg/ngm/statements/load"
)

func AggIndexNames() Aggregator {
	return &IndexNames{}
}

type IndexNames struct {
	v string
}

var _ Aggregator = (*IndexNames)(nil)

func (a *IndexNames) Add(record *load.StmtRecord) {
	if a.v == "" {
		a.v = strings.Join(record.IndexNames, ",")
	}
}

func (a *IndexNames) Merge(agg Aggregator) {
	if agg, ok := agg.(*IndexNames); ok {
		if a.v == "" {
			a.v = agg.v
		}
	}
}

func (a *IndexNames) Output(model *api.Model) {
	model.IndexNames = a.v
}