package metrics

import (
	grpcprom "github.com/grpc-ecosystem/go-grpc-prometheus"
	"github.com/prometheus/client_golang/prometheus"
	"sigs.k8s.io/controller-runtime/pkg/metrics"
)

const managerserverComponent = "managerserver"

var (
	RequestHistogram = prometheus.NewHistogramVec(
		prometheus.HistogramOpts{
			Subsystem: managerserverComponent,
			Name:      "request_seconds",
			Help:      "Histogram of request",
		},
		[]string{"req_name", "resp_code", "pool_ns"},
	)

	TiDBActiveDurationHistogram = prometheus.NewHistogramVec(
		prometheus.HistogramOpts{
			Subsystem: managerserverComponent,
			Name:      "tidb_active_duration_seconds",
			Help:      "Histogram of approximate TiDB active duration reported when a pod is freed",
			Buckets:   []float64{30, 60, 300, 600, 1800, 3600, 14400, 43200, 86400},
		},
		[]string{"pool_ns"},
	)
)

func init() {
	// Register custom metrics with the global prometheus registry
	metrics.Registry.MustRegister(RequestHistogram)
	metrics.Registry.MustRegister(TiDBActiveDurationHistogram)
	metrics.Registry.MustRegister(grpcprom.DefaultServerMetrics)
}