// +build windows

/*
Copyright 2019 The Kubernetes Authors.

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,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package winstats

import (
	"sync"

	cadvisorapi "github.com/google/cadvisor/info/v1"
	"k8s.io/apimachinery/pkg/util/sets"
	"k8s.io/klog"
)

const (
	packetsReceivedPerSecondQuery = "\\Network Adapter(*)\\Packets Received/sec"
	packetsSentPerSecondQuery     = "\\Network Adapter(*)\\Packets Sent/sec"
	bytesReceivedPerSecondQuery   = "\\Network Adapter(*)\\Bytes Received/sec"
	bytesSentPerSecondQuery       = "\\Network Adapter(*)\\Bytes Sent/sec"
	packetsReceivedDiscardedQuery = "\\Network Adapter(*)\\Packets Received Discarded"
	packetsReceivedErrorsQuery    = "\\Network Adapter(*)\\Packets Received Errors"
	packetsOutboundDiscardedQuery = "\\Network Adapter(*)\\Packets Outbound Discarded"
	packetsOutboundErrorsQuery    = "\\Network Adapter(*)\\Packets Outbound Errors"
)

// networkCounter contains the counters for network adapters.
type networkCounter struct {
	packetsReceivedPerSecondCounter *perfCounter
	packetsSentPerSecondCounter     *perfCounter
	bytesReceivedPerSecondCounter   *perfCounter
	bytesSentPerSecondCounter       *perfCounter
	packetsReceivedDiscardedCounter *perfCounter
	packetsReceivedErrorsCounter    *perfCounter
	packetsOutboundDiscardedCounter *perfCounter
	packetsOutboundErrorsCounter    *perfCounter

	mu           sync.RWMutex
	adapterStats map[string]cadvisorapi.InterfaceStats
}

func newNetworkCounters() (*networkCounter, error) {
	packetsReceivedPerSecondCounter, err := newPerfCounter(packetsReceivedPerSecondQuery)
	if err != nil {
		return nil, err
	}

	packetsSentPerSecondCounter, err := newPerfCounter(packetsSentPerSecondQuery)
	if err != nil {
		return nil, err
	}

	bytesReceivedPerSecondCounter, err := newPerfCounter(bytesReceivedPerSecondQuery)
	if err != nil {
		return nil, err
	}

	bytesSentPerSecondCounter, err := newPerfCounter(bytesSentPerSecondQuery)
	if err != nil {
		return nil, err
	}

	packetsReceivedDiscardedCounter, err := newPerfCounter(packetsReceivedDiscardedQuery)
	if err != nil {
		return nil, err
	}

	packetsReceivedErrorsCounter, err := newPerfCounter(packetsReceivedErrorsQuery)
	if err != nil {
		return nil, err
	}

	packetsOutboundDiscardedCounter, err := newPerfCounter(packetsOutboundDiscardedQuery)
	if err != nil {
		return nil, err
	}

	packetsOutboundErrorsCounter, err := newPerfCounter(packetsOutboundErrorsQuery)
	if err != nil {
		return nil, err
	}

	return &networkCounter{
		packetsReceivedPerSecondCounter: packetsReceivedPerSecondCounter,
		packetsSentPerSecondCounter:     packetsSentPerSecondCounter,
		bytesReceivedPerSecondCounter:   bytesReceivedPerSecondCounter,
		bytesSentPerSecondCounter:       bytesSentPerSecondCounter,
		packetsReceivedDiscardedCounter: packetsReceivedDiscardedCounter,
		packetsReceivedErrorsCounter:    packetsReceivedErrorsCounter,
		packetsOutboundDiscardedCounter: packetsOutboundDiscardedCounter,
		packetsOutboundErrorsCounter:    packetsOutboundErrorsCounter,
		adapterStats:                    map[string]cadvisorapi.InterfaceStats{},
	}, nil
}

func (n *networkCounter) getData() ([]cadvisorapi.InterfaceStats, error) {
	packetsReceivedPerSecondData, err := n.packetsReceivedPerSecondCounter.getDataList()
	if err != nil {
		klog.Errorf("Unable to get packetsReceivedPerSecond perf counter data; err: %v", err)
		return nil, err
	}

	packetsSentPerSecondData, err := n.packetsSentPerSecondCounter.getDataList()
	if err != nil {
		klog.Errorf("Unable to get packetsSentPerSecond perf counter data; err: %v", err)
		return nil, err
	}

	bytesReceivedPerSecondData, err := n.bytesReceivedPerSecondCounter.getDataList()
	if err != nil {
		klog.Errorf("Unable to get bytesReceivedPerSecond perf counter data; err: %v", err)
		return nil, err
	}

	bytesSentPerSecondData, err := n.bytesSentPerSecondCounter.getDataList()
	if err != nil {
		klog.Errorf("Unable to get bytesSentPerSecond perf counter data; err: %v", err)
		return nil, err
	}

	packetsReceivedDiscardedData, err := n.packetsReceivedDiscardedCounter.getDataList()
	if err != nil {
		klog.Errorf("Unable to get packetsReceivedDiscarded perf counter data; err: %v", err)
		return nil, err
	}

	packetsReceivedErrorsData, err := n.packetsReceivedErrorsCounter.getDataList()
	if err != nil {
		klog.Errorf("Unable to get packetsReceivedErrors perf counter data; err: %v", err)
		return nil, err
	}

	packetsOutboundDiscardedData, err := n.packetsOutboundDiscardedCounter.getDataList()
	if err != nil {
		klog.Errorf("Unable to get packetsOutboundDiscarded perf counter data; err: %v", err)
		return nil, err
	}

	packetsOutboundErrorsData, err := n.packetsOutboundErrorsCounter.getDataList()
	if err != nil {
		klog.Errorf("Unable to get packetsOutboundErrors perf counter data; err: %v", err)
		return nil, err
	}

	n.mu.Lock()
	defer n.mu.Unlock()
	n.mergeCollectedData(
		packetsReceivedPerSecondData,
		packetsSentPerSecondData,
		bytesReceivedPerSecondData,
		bytesSentPerSecondData,
		packetsReceivedDiscardedData,
		packetsReceivedErrorsData,
		packetsOutboundDiscardedData,
		packetsOutboundErrorsData,
	)
	return n.listInterfaceStats(), nil
}

// mergeCollectedData merges the collected data into cache. It should be invoked under lock protected.
func (n *networkCounter) mergeCollectedData(packetsReceivedPerSecondData,
	packetsSentPerSecondData,
	bytesReceivedPerSecondData,
	bytesSentPerSecondData,
	packetsReceivedDiscardedData,
	packetsReceivedErrorsData,
	packetsOutboundDiscardedData,
	packetsOutboundErrorsData map[string]uint64) {
	adapters := sets.NewString()

	// merge the collected data and list of adapters.
	adapters.Insert(n.mergePacketsReceivedPerSecondData(packetsReceivedPerSecondData)...)
	adapters.Insert(n.mergePacketsSentPerSecondData(packetsSentPerSecondData)...)
	adapters.Insert(n.mergeBytesReceivedPerSecondData(bytesReceivedPerSecondData)...)
	adapters.Insert(n.mergeBytesSentPerSecondData(bytesSentPerSecondData)...)
	adapters.Insert(n.mergePacketsReceivedDiscardedData(packetsReceivedDiscardedData)...)
	adapters.Insert(n.mergePacketsReceivedErrorsData(packetsReceivedErrorsData)...)
	adapters.Insert(n.mergePacketsOutboundDiscardedData(packetsOutboundDiscardedData)...)
	adapters.Insert(n.mergePacketsOutboundErrorsData(packetsOutboundErrorsData)...)

	// delete the cache for non-existing adapters.
	for adapter := range n.adapterStats {
		if !adapters.Has(adapter) {
			delete(n.adapterStats, adapter)
		}
	}
}

func (n *networkCounter) mergePacketsReceivedPerSecondData(packetsReceivedPerSecondData map[string]uint64) []string {
	var adapters []string
	for adapterName, value := range packetsReceivedPerSecondData {
		adapters = append(adapters, adapterName)
		newStat := n.adapterStats[adapterName]
		newStat.Name = adapterName
		newStat.RxPackets = newStat.RxPackets + value
		n.adapterStats[adapterName] = newStat
	}

	return adapters
}

func (n *networkCounter) mergePacketsSentPerSecondData(packetsSentPerSecondData map[string]uint64) []string {
	var adapters []string
	for adapterName, value := range packetsSentPerSecondData {
		adapters = append(adapters, adapterName)
		newStat := n.adapterStats[adapterName]
		newStat.Name = adapterName
		newStat.TxPackets = newStat.TxPackets + value
		n.adapterStats[adapterName] = newStat
	}

	return adapters
}

func (n *networkCounter) mergeBytesReceivedPerSecondData(bytesReceivedPerSecondData map[string]uint64) []string {
	var adapters []string
	for adapterName, value := range bytesReceivedPerSecondData {
		adapters = append(adapters, adapterName)
		newStat := n.adapterStats[adapterName]
		newStat.Name = adapterName
		newStat.RxBytes = newStat.RxBytes + value
		n.adapterStats[adapterName] = newStat
	}

	return adapters
}

func (n *networkCounter) mergeBytesSentPerSecondData(bytesSentPerSecondData map[string]uint64) []string {
	var adapters []string
	for adapterName, value := range bytesSentPerSecondData {
		adapters = append(adapters, adapterName)
		newStat := n.adapterStats[adapterName]
		newStat.Name = adapterName
		newStat.TxBytes = newStat.TxBytes + value
		n.adapterStats[adapterName] = newStat
	}

	return adapters
}

func (n *networkCounter) mergePacketsReceivedDiscardedData(packetsReceivedDiscardedData map[string]uint64) []string {
	var adapters []string
	for adapterName, value := range packetsReceivedDiscardedData {
		adapters = append(adapters, adapterName)
		newStat := n.adapterStats[adapterName]
		newStat.Name = adapterName
		newStat.RxDropped = value
		n.adapterStats[adapterName] = newStat
	}

	return adapters
}

func (n *networkCounter) mergePacketsReceivedErrorsData(packetsReceivedErrorsData map[string]uint64) []string {
	var adapters []string
	for adapterName, value := range packetsReceivedErrorsData {
		adapters = append(adapters, adapterName)
		newStat := n.adapterStats[adapterName]
		newStat.Name = adapterName
		newStat.RxErrors = value
		n.adapterStats[adapterName] = newStat
	}

	return adapters
}

func (n *networkCounter) mergePacketsOutboundDiscardedData(packetsOutboundDiscardedData map[string]uint64) []string {
	var adapters []string
	for adapterName, value := range packetsOutboundDiscardedData {
		adapters = append(adapters, adapterName)
		newStat := n.adapterStats[adapterName]
		newStat.Name = adapterName
		newStat.TxDropped = value
		n.adapterStats[adapterName] = newStat
	}

	return adapters
}

func (n *networkCounter) mergePacketsOutboundErrorsData(packetsOutboundErrorsData map[string]uint64) []string {
	var adapters []string
	for adapterName, value := range packetsOutboundErrorsData {
		adapters = append(adapters, adapterName)
		newStat := n.adapterStats[adapterName]
		newStat.Name = adapterName
		newStat.TxErrors = value
		n.adapterStats[adapterName] = newStat
	}

	return adapters
}

func (n *networkCounter) listInterfaceStats() []cadvisorapi.InterfaceStats {
	stats := make([]cadvisorapi.InterfaceStats, 0, len(n.adapterStats))
	for _, stat := range n.adapterStats {
		stats = append(stats, stat)
	}
	return stats
}
