// Copyright 2024 PingCAP, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// See the License for the specific language governing permissions and
// limitations under the License.

package metrics

import "github.com/prometheus/client_golang/prometheus"

var (
	MaintainerHandleEventDuration = prometheus.NewHistogramVec(
		prometheus.HistogramOpts{
			Namespace: "ticdc",
			Subsystem: "maintainer",
			Name:      "handle_event_duration",
			Help:      "Bucketed histogram of maintainer handle event time (s).",
			Buckets:   prometheus.ExponentialBuckets(0.01 /* 10 ms */, 2, 18),
		}, []string{getKeyspaceLabel(), "changefeed"})

	MaintainerEventChLenGauge = prometheus.NewGaugeVec(
		prometheus.GaugeOpts{
			Namespace: "ticdc",
			Subsystem: "maintainer",
			Name:      "event_ch_len",
			Help:      "length of maintainer event channel",
		}, []string{getKeyspaceLabel(), "changefeed"})

	OperatorCount = prometheus.NewGaugeVec(
		prometheus.GaugeOpts{
			Namespace: "ticdc",
			Subsystem: "maintainer",
			Name:      "created_count",
			Help:      "number of created operators",
		}, []string{getKeyspaceLabel(), "changefeed", "type", "mode"})

	TotalOperatorCount = prometheus.NewGaugeVec(
		prometheus.GaugeOpts{
			Namespace: "ticdc",
			Subsystem: "maintainer",
			Name:      "total_operator_count",
			Help:      "number of total operators",
		}, []string{getKeyspaceLabel(), "changefeed", "type", "mode"})

	OperatorDuration = prometheus.NewHistogramVec(
		prometheus.HistogramOpts{
			Namespace: "ticdc",
			Subsystem: "maintainer",
			Name:      "finish_operators_duration_seconds",
			Help:      "Bucketed histogram of processing time (s) of finished operator.",
			Buckets:   []float64{0.5, 1, 2, 4, 8, 16, 20, 40, 60, 90, 120, 180, 240, 300, 480, 600, 720, 900, 1200, 1800, 3600},
		}, []string{getKeyspaceLabel(), "changefeed", "type", "mode"})
)

func initMaintainerMetrics(registry *prometheus.Registry) {
	registry.MustRegister(MaintainerHandleEventDuration)
	registry.MustRegister(MaintainerEventChLenGauge)
	registry.MustRegister(OperatorCount)
	registry.MustRegister(OperatorDuration)
	registry.MustRegister(TotalOperatorCount)
}