package aggregate

import (
	"math"

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

func AggMaxMem() Aggregator {
	return &MaxMem{math.MinInt64}
}

type MaxMem struct {
	max int64
}

var _ Aggregator = (*MaxMem)(nil)

func (a *MaxMem) Add(record *load.StmtRecord) {
	if record.MaxMem > a.max {
		a.max = record.MaxMem
	}
}

func (a *MaxMem) Merge(agg Aggregator) {
	if agg, ok := agg.(*MaxMem); ok {
		if agg.max > a.max {
			a.max = agg.max
		}
	}
}

func (a *MaxMem) Output(model *api.Model) {
	model.MaxMem = int(a.max)
}