package metrics

import (
	"strconv"
	"time"

	"git.frostfs.info/TrueCloudLab/frostfs-observability/metrics"
	"github.com/prometheus/client_golang/prometheus"
)

type BlobTreeMetrics interface {
	SetBlobTreeMode(shardID, path string, readOnly bool)
	CloseBlobTree(shardID, path string)
	BlobTreeMethodDuration(shardID, path string, method string, d time.Duration, success bool, withStorageID NullBool)
	IncBlobTreeFilesCount(shardID, path string)
	DecBlobTreeFilesCount(shardID, path string)
	AddBlobTreePut(shardID, path string, size int)
	AddBlobTreeGet(shardID, path string, size int)
}

type blobTreeMetrics struct {
	mode        *shardIDPathModeValue
	reqDuration *prometheus.HistogramVec
	put         *prometheus.CounterVec
	get         *prometheus.CounterVec
	filesCount  *prometheus.GaugeVec
}

func newBlobTreeMetrics() *blobTreeMetrics {
	return &blobTreeMetrics{
		mode: newShardIDPathMode(blobTreeSubSystem, "mode", "Blob tree mode"),

		reqDuration: metrics.NewHistogramVec(prometheus.HistogramOpts{
			Namespace: namespace,
			Subsystem: blobTreeSubSystem,
			Name:      "request_duration_seconds",
			Help:      "Accumulated Blob tree request process duration",
		}, []string{shardIDLabel, pathLabel, successLabel, methodLabel, withStorageIDLabel}),
		put: metrics.NewCounterVec(prometheus.CounterOpts{
			Namespace: namespace,
			Subsystem: blobTreeSubSystem,
			Name:      "put_bytes",
			Help:      "Accumulated payload size written to Blob tree",
		}, []string{shardIDLabel, pathLabel}),
		get: metrics.NewCounterVec(prometheus.CounterOpts{
			Namespace: namespace,
			Subsystem: blobTreeSubSystem,
			Name:      "get_bytes",
			Help:      "Accumulated payload size read from Blob tree",
		}, []string{shardIDLabel, pathLabel}),
		filesCount: metrics.NewGaugeVec(prometheus.GaugeOpts{
			Namespace: namespace,
			Subsystem: blobTreeSubSystem,
			Name:      "files_count",
			Help:      "Count of data files in Blob tree",
		}, []string{shardIDLabel, pathLabel}),
	}
}

func (b *blobTreeMetrics) SetBlobTreeMode(shardID, path string, readOnly bool) {
	b.mode.SetMode(shardID, path, modeFromBool(readOnly))
}

func (b *blobTreeMetrics) CloseBlobTree(shardID, path string) {
	b.mode.SetMode(shardID, path, closedMode)
	b.reqDuration.DeletePartialMatch(prometheus.Labels{
		shardIDLabel: shardID,
		pathLabel:    path,
	})
	b.get.DeletePartialMatch(prometheus.Labels{
		shardIDLabel: shardID,
		pathLabel:    path,
	})
	b.put.DeletePartialMatch(prometheus.Labels{
		shardIDLabel: shardID,
		pathLabel:    path,
	})
	b.filesCount.DeletePartialMatch(prometheus.Labels{
		shardIDLabel: shardID,
		pathLabel:    path,
	})
}

func (b *blobTreeMetrics) BlobTreeMethodDuration(shardID, path string, method string, d time.Duration, success bool, withStorageID NullBool) {
	b.reqDuration.With(prometheus.Labels{
		shardIDLabel:       shardID,
		pathLabel:          path,
		successLabel:       strconv.FormatBool(success),
		methodLabel:        method,
		withStorageIDLabel: withStorageID.String(),
	}).Observe(d.Seconds())
}

func (b *blobTreeMetrics) IncBlobTreeFilesCount(shardID, path string) {
	b.filesCount.With(prometheus.Labels{
		shardIDLabel: shardID,
		pathLabel:    path,
	}).Inc()
}

func (b *blobTreeMetrics) DecBlobTreeFilesCount(shardID, path string) {
	b.filesCount.With(prometheus.Labels{
		shardIDLabel: shardID,
		pathLabel:    path,
	}).Dec()
}

func (b *blobTreeMetrics) AddBlobTreePut(shardID, path string, size int) {
	b.put.With(prometheus.Labels{
		shardIDLabel: shardID,
		pathLabel:    path,
	}).Add(float64(size))
}

func (b *blobTreeMetrics) AddBlobTreeGet(shardID, path string, size int) {
	b.get.With(prometheus.Labels{
		shardIDLabel: shardID,
		pathLabel:    path,
	}).Add(float64(size))
}