const (
	MetricFamilyCpu        MetricFamily = "cpu"
	MetricFamilyFilesystem              = "filesystem"
	MetricFamilyMemory                  = "memory"
	MetricFamilyNetwork                 = "network"
	MetricFamilyGeneral                 = "general"
)

const (
	CustomMetricPrefix = "custom/"
)

var (
	LabelMetricSetType = LabelDescriptor{
		Key:         "type",
		Description: "Type of the metrics set (container, pod, namespace, node, cluster)",
	}
	MetricSetTypeSystemContainer = "sys_container"
	MetricSetTypePodContainer    = "pod_container"
	MetricSetTypePod             = "pod"
	MetricSetTypeNamespace       = "ns"
	MetricSetTypeNode            = "node"
	MetricSetTypeCluster         = "cluster"

	LabelPodId = LabelDescriptor{
		Key:         "pod_id",
		Description: "The unique ID of the pod",
	}
	LabelPodName = LabelDescriptor{
		Key:         "pod_name",
		Description: "The name of the pod",
	}
	LabelNamespaceName = LabelDescriptor{
		Key:         "namespace_name",
		Description: "The name of the namespace",
	}
	LabelPodNamespaceUID = LabelDescriptor{
		Key:         "namespace_id",
		Description: "The UID of namespace of the pod",
	}
	LabelContainerName = LabelDescriptor{
		Key:         "container_name",
		Description: "User-provided name of the container or full container name for system containers",
	}
	LabelLabels = LabelDescriptor{
		Key:         "labels",
		Description: "Comma-separated list of user-provided labels",
	}
	LabelNodename = LabelDescriptor{
		Key:         "nodename",
		Description: "nodename where the container ran",
	}
	LabelHostname = LabelDescriptor{
		Key:         "hostname",
		Description: "Hostname where the container ran",
	}
	LabelResourceID = LabelDescriptor{
		Key:         "resource_id",
		Description: "Identifier(s) specific to a metric",
	}
	LabelHostID = LabelDescriptor{
		Key:         "host_id",
		Description: "Identifier specific to a host. Set by cloud provider or user",
	}
	LabelContainerBaseImage = LabelDescriptor{
		Key:         "container_base_image",
		Description: "User-defined image name that is run inside the container",
	}
	// The label is populated only for GCM
	LabelCustomMetricName = LabelDescriptor{
		Key:         "custom_metric_name",
		Description: "User-defined name of the exported custom metric",
	}
	LabelGCEResourceID = LabelDescriptor{
		Key:         "resource_id",
		Description: "Resource id for nodes specific for GCE.",
	}
	LabelGCEResourceType = LabelDescriptor{
		Key:         "resource_type",
		Description: "Resource types for nodes specific for GCE.",
	}
	LabelNodeSchedulable = LabelDescriptor{
		Key:         "schedulable",
		Description: "Node schedulable status.",
	}
	LabelVolumeName = LabelDescriptor{
		Key:         "volume_name",
		Description: "The name of the volume.",
	}
	LabelAcceleratorMake = LabelDescriptor{
		Key:         "make",
		Description: "Make of the accelerator (nvidia, amd, google etc.)",
	}
	LabelAcceleratorModel = LabelDescriptor{
		Key:         "model",
		Description: "Model of the accelerator (tesla-p100, tesla-k80 etc.)",
	}
	LabelAcceleratorID = LabelDescriptor{
		Key:         "accelerator_id",
		Description: "ID of the accelerator",
	}
)

var AdditionalMetrics = []Metric{
	MetricCpuRequest,
	MetricCpuLimit,
	MetricMemoryRequest,
	MetricMemoryLimit}

var AllAggregations = map[AggregationType]bool{
	AggregationTypeAverage:      true,
	AggregationTypeMaximum:      true,
	AggregationTypeMinimum:      true,
	AggregationTypeMedian:       true,
	AggregationTypePercentile50: true,
	AggregationTypePercentile95: true,
	AggregationTypePercentile99: true,
	AggregationTypeCount:        true,
}

var AllMetrics = append(append(append(append(StandardMetrics, AdditionalMetrics...), RateMetrics...), LabeledMetrics...),
	NodeAutoscalingMetrics...)

var CpuMetrics = []Metric{
	MetricCpuLimit,
	MetricCpuRequest,
	MetricCpuUsage,
	MetricCpuUsageRate,
	MetricNodeCpuAllocatable,
	MetricNodeCpuCapacity,
	MetricNodeCpuReservation,
	MetricNodeCpuUtilization,
}

var FilesystemMetrics = []Metric{
	MetricFilesystemAvailable,
	MetricFilesystemLimit,
	MetricFilesystemUsage,
	MetricFilesystemInodes,
	MetricFilesystemInodesFree,
}

var LabeledMetrics = []Metric{
	MetricDiskIORead,
	MetricDiskIOReadRate,
	MetricDiskIOWrite,
	MetricDiskIOWriteRate,
	MetricFilesystemUsage,
	MetricFilesystemLimit,
	MetricFilesystemAvailable,
	MetricFilesystemInodes,
	MetricFilesystemInodesFree,
	MetricAcceleratorMemoryTotal,
	MetricAcceleratorMemoryUsed,
	MetricAcceleratorDutyCycle,
}

var MemoryMetrics = []Metric{
	MetricMemoryLimit,
	MetricMemoryMajorPageFaults,
	MetricMemoryMajorPageFaultsRate,
	MetricMemoryPageFaults,
	MetricMemoryPageFaultsRate,
	MetricMemoryRequest,
	MetricMemoryUsage,
	MetricMemoryRSS,
	MetricMemoryCache,
	MetricMemoryWorkingSet,
	MetricNodeMemoryAllocatable,
	MetricNodeMemoryCapacity,
	MetricNodeMemoryUtilization,
	MetricNodeMemoryReservation,
}

var MetricAcceleratorDutyCycle = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "accelerator/duty_cycle",
		Description: "Percent of time over the past sample period (10s) during which the accelerator was actively processing",
		Labels:      acceleratorLabels,
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsCount,
	},
	HasLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) bool {
		if len(stat.Accelerators) == 0 {
			return false
		}

		return true
	},
	GetLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) []LabeledMetric {
		result := make([]LabeledMetric, 0, len(stat.Accelerators))
		for _, ac := range stat.Accelerators {
			result = append(result, LabeledMetric{
				Name: "accelerator/duty_cycle",
				Labels: map[string]string{
					LabelAcceleratorMake.Key:  ac.Make,
					LabelAcceleratorModel.Key: ac.Model,
					LabelAcceleratorID.Key:    ac.ID,
				},
				MetricValue: MetricValue{
					ValueType:  ValueInt64,
					MetricType: MetricGauge,
					IntValue:   int64(ac.DutyCycle),
				},
			})
		}
		return result
	},
}

var MetricAcceleratorMemoryTotal = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "accelerator/memory_total",
		Description: "Total accelerator memory (in bytes)",
		Labels:      acceleratorLabels,
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
	},
	HasLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) bool {
		if len(stat.Accelerators) == 0 {
			return false
		}

		return true
	},
	GetLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) []LabeledMetric {
		result := make([]LabeledMetric, 0, len(stat.Accelerators))
		for _, ac := range stat.Accelerators {
			result = append(result, LabeledMetric{
				Name: "accelerator/memory_total",
				Labels: map[string]string{
					LabelAcceleratorMake.Key:  ac.Make,
					LabelAcceleratorModel.Key: ac.Model,
					LabelAcceleratorID.Key:    ac.ID,
				},
				MetricValue: MetricValue{
					ValueType:  ValueInt64,
					MetricType: MetricGauge,
					IntValue:   int64(ac.MemoryTotal),
				},
			})
		}
		return result
	},
}

var MetricAcceleratorMemoryUsed = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "accelerator/memory_used",
		Description: "Total accelerator memory allocated (in bytes)",
		Labels:      acceleratorLabels,
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
	},
	HasLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) bool {
		if len(stat.Accelerators) == 0 {
			return false
		}

		return true
	},
	GetLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) []LabeledMetric {
		result := make([]LabeledMetric, 0, len(stat.Accelerators))
		for _, ac := range stat.Accelerators {
			result = append(result, LabeledMetric{
				Name: "accelerator/memory_used",
				Labels: map[string]string{
					LabelAcceleratorMake.Key:  ac.Make,
					LabelAcceleratorModel.Key: ac.Model,
					LabelAcceleratorID.Key:    ac.ID,
				},
				MetricValue: MetricValue{
					ValueType:  ValueInt64,
					MetricType: MetricGauge,
					IntValue:   int64(ac.MemoryUsed),
				},
			})
		}
		return result
	},
}

var MetricCpuLimit = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "cpu/limit",
		Description: "CPU hard limit in millicores.",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsCount,
	},
}

var MetricCpuRequest = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "cpu/request",
		Description: "CPU request (the guaranteed amount of resources) in millicores. This metric is Kubernetes specific.",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsCount,
	},
}

var MetricCpuUsage = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "cpu/usage",
		Description: "Cumulative CPU usage on all cores",
		Type:        MetricCumulative,
		ValueType:   ValueInt64,
		Units:       UnitsNanoseconds,
	},
	HasValue: func(spec *cadvisor.ContainerSpec) bool {
		return spec.HasCpu
	},
	GetValue: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) MetricValue {
		return MetricValue{
			ValueType:  ValueInt64,
			MetricType: MetricCumulative,
			IntValue:   int64(stat.Cpu.Usage.Total)}
	},
}

var MetricCpuUsageRate = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "cpu/usage_rate",
		Description: "CPU usage on all cores in millicores",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsCount,
	},
}

var MetricDiskIORead = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "disk/io_read_bytes",
		Description: "Cumulative number of bytes read over disk",
		Type:        MetricCumulative,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
		Labels:      metricLabels,
	},
	HasLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) bool {
		return spec.HasDiskIo
	},
	GetLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) []LabeledMetric {
		result := make([]LabeledMetric, 0, len(stat.DiskIo.IoServiceBytes))
		for _, ioServiceBytesPerPartition := range stat.DiskIo.IoServiceBytes {
			resourceIDKey := ioServiceBytesPerPartition.Device
			if resourceIDKey == "" {
				resourceIDKey = fmt.Sprintf("%d:%d", ioServiceBytesPerPartition.Major, ioServiceBytesPerPartition.Minor)
			}

			var value uint64
			if v, exists := ioServiceBytesPerPartition.Stats["Read"]; exists {
				value = v
			}

			result = append(result, LabeledMetric{
				Name: "disk/io_read_bytes",
				Labels: map[string]string{
					LabelResourceID.Key: resourceIDKey,
				},
				MetricValue: MetricValue{
					ValueType:  ValueInt64,
					MetricType: MetricGauge,
					IntValue:   int64(value),
				},
			})
		}
		return result
	},
}

var MetricDiskIOReadRate = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "disk/io_read_bytes_rate",
		Description: "Rate of bytes read over disk in bytes per second",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
		Labels:      metricLabels,
	},
}

var MetricDiskIOWrite = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "disk/io_write_bytes",
		Description: "Cumulative number of bytes write over disk",
		Type:        MetricCumulative,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
		Labels:      metricLabels,
	},
	HasLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) bool {
		return spec.HasDiskIo
	},
	GetLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) []LabeledMetric {
		result := make([]LabeledMetric, 0, len(stat.DiskIo.IoServiceBytes))
		for _, ioServiceBytesPerPartition := range stat.DiskIo.IoServiceBytes {
			resourceIDKey := ioServiceBytesPerPartition.Device
			if resourceIDKey == "" {
				resourceIDKey = fmt.Sprintf("%d:%d", ioServiceBytesPerPartition.Major, ioServiceBytesPerPartition.Minor)
			}

			var value uint64
			if v, exists := ioServiceBytesPerPartition.Stats["Write"]; exists {
				value = v
			}

			result = append(result, LabeledMetric{
				Name: "disk/io_write_bytes",
				Labels: map[string]string{
					LabelResourceID.Key: resourceIDKey,
				},
				MetricValue: MetricValue{
					ValueType:  ValueInt64,
					MetricType: MetricGauge,
					IntValue:   int64(value),
				},
			})
		}
		return result
	},
}

var MetricDiskIOWriteRate = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "disk/io_write_bytes_rate",
		Description: "Rate of bytes written over disk in bytes per second",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
		Labels:      metricLabels,
	},
}

var MetricFamilies = map[MetricFamily][]Metric{
	MetricFamilyCpu:        CpuMetrics,
	MetricFamilyFilesystem: FilesystemMetrics,
	MetricFamilyMemory:     MemoryMetrics,
	MetricFamilyNetwork:    NetworkMetrics,
}

var MetricFilesystemAvailable = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "filesystem/available",
		Description: "The number of available bytes remaining in a the filesystem",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
		Labels:      metricLabels,
	},
	HasLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) bool {
		return spec.HasFilesystem
	},
	GetLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) []LabeledMetric {
		result := make([]LabeledMetric, 0, len(stat.Filesystem))
		for _, fs := range stat.Filesystem {
			result = append(result, LabeledMetric{
				Name: "filesystem/available",
				Labels: map[string]string{
					LabelResourceID.Key: fs.Device,
				},
				MetricValue: MetricValue{
					ValueType:  ValueInt64,
					MetricType: MetricGauge,
					IntValue:   int64(fs.Available),
				},
			})
		}
		return result
	},
}

var MetricFilesystemInodes = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "filesystem/inodes",
		Description: "Total number of inodes on a filesystem",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
		Labels:      metricLabels,
	},
	HasLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) bool {
		return spec.HasFilesystem
	},
	GetLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) []LabeledMetric {
		result := []LabeledMetric{}
		for _, fs := range stat.Filesystem {
			if fs.HasInodes {
				result = append(result, LabeledMetric{
					Name: "filesystem/inodes",
					Labels: map[string]string{
						LabelResourceID.Key: fs.Device,
					},
					MetricValue: MetricValue{
						ValueType:  ValueInt64,
						MetricType: MetricGauge,
						IntValue:   int64(fs.Inodes),
					},
				})
			}
		}
		return result
	},
}

var MetricFilesystemInodesFree = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "filesystem/inodes_free",
		Description: "Free number of inodes on a filesystem",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
		Labels:      metricLabels,
	},
	HasLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) bool {
		return spec.HasFilesystem
	},
	GetLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) []LabeledMetric {
		result := []LabeledMetric{}
		for _, fs := range stat.Filesystem {
			if fs.HasInodes {
				result = append(result, LabeledMetric{
					Name: "filesystem/inodes_free",
					Labels: map[string]string{
						LabelResourceID.Key: fs.Device,
					},
					MetricValue: MetricValue{
						ValueType:  ValueInt64,
						MetricType: MetricGauge,
						IntValue:   int64(fs.InodesFree),
					},
				})
			}
		}
		return result
	},
}

var MetricFilesystemLimit = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "filesystem/limit",
		Description: "The total size of filesystem in bytes",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
		Labels:      metricLabels,
	},
	HasLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) bool {
		return spec.HasFilesystem
	},
	GetLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) []LabeledMetric {
		result := make([]LabeledMetric, 0, len(stat.Filesystem))
		for _, fs := range stat.Filesystem {
			result = append(result, LabeledMetric{
				Name: "filesystem/limit",
				Labels: map[string]string{
					LabelResourceID.Key: fs.Device,
				},
				MetricValue: MetricValue{
					ValueType:  ValueInt64,
					MetricType: MetricGauge,
					IntValue:   int64(fs.Limit),
				},
			})
		}
		return result
	},
}

var MetricFilesystemUsage = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "filesystem/usage",
		Description: "Total number of bytes consumed on a filesystem",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
		Labels:      metricLabels,
	},
	HasLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) bool {
		return spec.HasFilesystem
	},
	GetLabeledMetric: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) []LabeledMetric {
		result := make([]LabeledMetric, 0, len(stat.Filesystem))
		for _, fs := range stat.Filesystem {
			result = append(result, LabeledMetric{
				Name: "filesystem/usage",
				Labels: map[string]string{
					LabelResourceID.Key: fs.Device,
				},
				MetricValue: MetricValue{
					ValueType:  ValueInt64,
					MetricType: MetricGauge,
					IntValue:   int64(fs.Usage),
				},
			})
		}
		return result
	},
}

var MetricMemoryCache = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/cache",
		Description: "Cache memory",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
	},
	HasValue: func(spec *cadvisor.ContainerSpec) bool {
		return spec.HasMemory
	},
	GetValue: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) MetricValue {
		return MetricValue{
			ValueType:  ValueInt64,
			MetricType: MetricGauge,
			IntValue:   int64(stat.Memory.Cache)}
	},
}

var MetricMemoryLimit = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/limit",
		Description: "Memory hard limit in bytes.",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
	},
}

var MetricMemoryMajorPageFaults = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/major_page_faults",
		Description: "Number of major page faults",
		Type:        MetricCumulative,
		ValueType:   ValueInt64,
		Units:       UnitsCount,
	},
	HasValue: func(spec *cadvisor.ContainerSpec) bool {
		return spec.HasMemory
	},
	GetValue: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) MetricValue {
		return MetricValue{
			ValueType:  ValueInt64,
			MetricType: MetricCumulative,
			IntValue:   int64(stat.Memory.ContainerData.Pgmajfault)}
	},
}

var MetricMemoryMajorPageFaultsRate = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/major_page_faults_rate",
		Description: "Rate of major page faults in counts per second",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricMemoryPageFaults = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/page_faults",
		Description: "Number of page faults",
		Type:        MetricCumulative,
		ValueType:   ValueInt64,
		Units:       UnitsCount,
	},
	HasValue: func(spec *cadvisor.ContainerSpec) bool {
		return spec.HasMemory
	},
	GetValue: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) MetricValue {
		return MetricValue{
			ValueType:  ValueInt64,
			MetricType: MetricCumulative,
			IntValue:   int64(stat.Memory.ContainerData.Pgfault)}
	},
}

var MetricMemoryPageFaultsRate = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/page_faults_rate",
		Description: "Rate of page faults in counts per second",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricMemoryRSS = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/rss",
		Description: "RSS memory",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
	},
	HasValue: func(spec *cadvisor.ContainerSpec) bool {
		return spec.HasMemory
	},
	GetValue: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) MetricValue {
		return MetricValue{
			ValueType:  ValueInt64,
			MetricType: MetricGauge,
			IntValue:   int64(stat.Memory.RSS)}
	},
}

var MetricMemoryRequest = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/request",
		Description: "Memory request (the guaranteed amount of resources) in bytes. This metric is Kubernetes specific.",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
	},
}

var MetricMemoryUsage = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/usage",
		Description: "Total memory usage",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
	},
	HasValue: func(spec *cadvisor.ContainerSpec) bool {
		return spec.HasMemory
	},
	GetValue: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) MetricValue {
		return MetricValue{
			ValueType:  ValueInt64,
			MetricType: MetricGauge,
			IntValue:   int64(stat.Memory.Usage)}
	},
}

var MetricMemoryWorkingSet = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/working_set",
		Description: "Total working set usage. Working set is the memory being used and not easily dropped by the kernel",
		Type:        MetricGauge,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
	},
	HasValue: func(spec *cadvisor.ContainerSpec) bool {
		return spec.HasMemory
	},
	GetValue: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) MetricValue {
		return MetricValue{
			ValueType:  ValueInt64,
			MetricType: MetricGauge,
			IntValue:   int64(stat.Memory.WorkingSet)}
	},
}

var MetricNetworkRx = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "network/rx",
		Description: "Cumulative number of bytes received over the network",
		Type:        MetricCumulative,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
	},
	HasValue: func(spec *cadvisor.ContainerSpec) bool {
		return spec.HasNetwork
	},
	GetValue: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) MetricValue {
		var rxBytes uint64 = 0
		for _, interfaceStat := range stat.Network.Interfaces {
			rxBytes += interfaceStat.RxBytes
		}
		return MetricValue{
			ValueType:  ValueInt64,
			MetricType: MetricCumulative,
			IntValue:   int64(rxBytes),
		}
	},
}

var MetricNetworkRxErrors = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "network/rx_errors",
		Description: "Cumulative number of errors while receiving over the network",
		Type:        MetricCumulative,
		ValueType:   ValueInt64,
		Units:       UnitsCount,
	},
	HasValue: func(spec *cadvisor.ContainerSpec) bool {
		return spec.HasNetwork
	},
	GetValue: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) MetricValue {
		var rxErrors uint64 = 0
		for _, interfaceStat := range stat.Network.Interfaces {
			rxErrors += interfaceStat.RxErrors
		}
		return MetricValue{
			ValueType:  ValueInt64,
			MetricType: MetricCumulative,
			IntValue:   int64(rxErrors),
		}
	},
}

var MetricNetworkRxErrorsRate = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "network/rx_errors_rate",
		Description: "Rate of errors sending over the network in errors per second",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricNetworkRxRate = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "network/rx_rate",
		Description: "Rate of bytes received over the network in bytes per second",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricNetworkTx = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "network/tx",
		Description: "Cumulative number of bytes sent over the network",
		Type:        MetricCumulative,
		ValueType:   ValueInt64,
		Units:       UnitsBytes,
	},
	HasValue: func(spec *cadvisor.ContainerSpec) bool {
		return spec.HasNetwork
	},
	GetValue: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) MetricValue {
		var txBytes uint64 = 0
		for _, interfaceStat := range stat.Network.Interfaces {
			txBytes += interfaceStat.TxBytes
		}
		return MetricValue{
			ValueType:  ValueInt64,
			MetricType: MetricCumulative,
			IntValue:   int64(txBytes),
		}
	},
}

var MetricNetworkTxErrors = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "network/tx_errors",
		Description: "Cumulative number of errors while sending over the network",
		Type:        MetricCumulative,
		ValueType:   ValueInt64,
		Units:       UnitsCount,
	},
	HasValue: func(spec *cadvisor.ContainerSpec) bool {
		return spec.HasNetwork
	},
	GetValue: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) MetricValue {
		var txErrors uint64 = 0
		for _, interfaceStat := range stat.Network.Interfaces {
			txErrors += interfaceStat.TxErrors
		}
		return MetricValue{
			ValueType:  ValueInt64,
			MetricType: MetricCumulative,
			IntValue:   int64(txErrors),
		}
	},
}

var MetricNetworkTxErrorsRate = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "network/tx_errors_rate",
		Description: "Rate of errors transmitting over the network in errors per second",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricNetworkTxRate = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "network/tx_rate",
		Description: "Rate of bytes transmitted over the network in bytes per second",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricNodeCpuAllocatable = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "cpu/node_allocatable",
		Description: "Cpu allocatable of a node",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricNodeCpuCapacity = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "cpu/node_capacity",
		Description: "Cpu capacity of a node",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricNodeCpuReservation = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "cpu/node_reservation",
		Description: "Share of cpu that is reserved on the node",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricNodeCpuUtilization = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "cpu/node_utilization",
		Description: "Cpu utilization as a share of node capacity",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricNodeMemoryAllocatable = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/node_allocatable",
		Description: "Memory allocatable of a node",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricNodeMemoryCapacity = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/node_capacity",
		Description: "Memory capacity of a node",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricNodeMemoryReservation = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/node_reservation",
		Description: "Share of memory that is reserved on the node",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricNodeMemoryUtilization = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "memory/node_utilization",
		Description: "Memory utilization as a share of memory capacity",
		Type:        MetricGauge,
		ValueType:   ValueFloat,
		Units:       UnitsCount,
	},
}

var MetricRestartCount = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "restart_count",
		Description: "Number of container restarts",
		Type:        MetricCumulative,
		ValueType:   ValueInt64,
		Units:       UnitsCount,
	},
}

var MetricUptime = Metric{
	MetricDescriptor: MetricDescriptor{
		Name:        "uptime",
		Description: "Number of milliseconds since the container was started",
		Type:        MetricCumulative,
		ValueType:   ValueInt64,
		Units:       UnitsMilliseconds,
	},
	HasValue: func(spec *cadvisor.ContainerSpec) bool {
		return !spec.CreationTime.IsZero()
	},
	GetValue: func(spec *cadvisor.ContainerSpec, stat *cadvisor.ContainerStats) MetricValue {
		return MetricValue{
			ValueType:  ValueInt64,
			MetricType: MetricCumulative,
			IntValue:   time.Since(spec.CreationTime).Nanoseconds() / time.Millisecond.Nanoseconds()}
	},
}

var MultiTypedAggregations = []AggregationType{
	AggregationTypeAverage,
	AggregationTypeMaximum,
	AggregationTypeMinimum,
	AggregationTypeMedian,
	AggregationTypePercentile50,
	AggregationTypePercentile95,
	AggregationTypePercentile99,
}

var NetworkMetrics = []Metric{
	MetricNetworkRx,
	MetricNetworkRxErrors,
	MetricNetworkRxErrorsRate,
	MetricNetworkRxRate,
	MetricNetworkTx,
	MetricNetworkTxErrors,
	MetricNetworkTxErrorsRate,
	MetricNetworkTxRate,
}

var NodeAutoscalingMetrics = []Metric{
	MetricNodeCpuCapacity,
	MetricNodeMemoryCapacity,
	MetricNodeCpuAllocatable,
	MetricNodeMemoryAllocatable,
	MetricNodeCpuUtilization,
	MetricNodeMemoryUtilization,
	MetricNodeCpuReservation,
	MetricNodeMemoryReservation,
}

var RateMetrics = []Metric{
	MetricCpuUsageRate,
	MetricMemoryPageFaultsRate,
	MetricMemoryMajorPageFaultsRate,
	MetricNetworkRxRate,
	MetricNetworkRxErrorsRate,
	MetricNetworkTxRate,
	MetricNetworkTxErrorsRate,
	MetricDiskIOReadRate,
	MetricDiskIOWriteRate}

var RateMetricsMapping = map[string]Metric{
	MetricCpuUsage.MetricDescriptor.Name:              MetricCpuUsageRate,
	MetricMemoryPageFaults.MetricDescriptor.Name:      MetricMemoryPageFaultsRate,
	MetricMemoryMajorPageFaults.MetricDescriptor.Name: MetricMemoryMajorPageFaultsRate,
	MetricNetworkRx.MetricDescriptor.Name:             MetricNetworkRxRate,
	MetricNetworkRxErrors.MetricDescriptor.Name:       MetricNetworkRxErrorsRate,
	MetricNetworkTx.MetricDescriptor.Name:             MetricNetworkTxRate,
	MetricNetworkTxErrors.MetricDescriptor.Name:       MetricNetworkTxErrorsRate,
	MetricDiskIORead.MetricDescriptor.Name:            MetricDiskIOReadRate,
	MetricDiskIOWrite.MetricDescriptor.Name:           MetricDiskIOWriteRate}

var StandardMetrics = []Metric{
	MetricUptime,
	MetricCpuUsage,
	MetricMemoryUsage,
	MetricMemoryRSS,
	MetricMemoryCache,
	MetricMemoryWorkingSet,
	MetricMemoryPageFaults,
	MetricMemoryMajorPageFaults,
	MetricNetworkRx,
	MetricNetworkRxErrors,
	MetricNetworkTx,
	MetricNetworkTxErrors}

type AggregationType string

var (
	AggregationTypeAverage      AggregationType = "average"
	AggregationTypeMaximum      AggregationType = "max"
	AggregationTypeMinimum      AggregationType = "min"
	AggregationTypeMedian       AggregationType = "median"
	AggregationTypeCount        AggregationType = "count"
	AggregationTypePercentile50 AggregationType = "50-perc"
	AggregationTypePercentile95 AggregationType = "95-perc"
	AggregationTypePercentile99 AggregationType = "99-perc"
)

type AggregationValue struct {
	Count *uint64

	Aggregations map[AggregationType]MetricValue
}

type AsHistoricalSource interface {
	// Historical returns the historical data access interface for this sink
	Historical() HistoricalSource
}

type DataBatch struct {
	Timestamp time.Time
	// Should use key functions from ms_keys.go
	MetricSets map[string]*MetricSet
}

type DataProcessor interface {
	Name() string
	Process(*DataBatch) (*DataBatch, error)
}

type DataSink interface {
	Name() string

	// Exports data to the external storage. The function should be synchronous/blocking and finish only
	// after the given DataBatch was written. This will allow sink manager to push data only to these
	// sinks that finished writing the previous data.
	ExportData(*DataBatch)
	Stop()
}

type HistoricalKey struct {
	// ObjectType specifies which type of object this is for (pod, namespace, etc)
	// It should be one of the MetricSetType* labels.
	ObjectType string

	// NodeName is used for node and system-container metrics
	NodeName string
	// NamespaceName is used for namespace, pod, and pod-container metrics
	NamespaceName string
	// PodName is used for pod and pod-container metrics
	PodName string
	// ContainerName is used for system-container and pod-container metrics
	ContainerName string
	// PodId may be used in place of the combination of PodName and NamespaceName for pod and pod-container metrics
	PodId string
}

type HistoricalSource interface {
	// GetMetric retrieves the given metric for one or more objects (specified by metricKeys) of
	// the same type, within the given time interval.  A start time of zero indicates no starting bound,
	// while an end time of zero indicates no ending bound.
	GetMetric(metricName string, metricKeys []HistoricalKey, start, end time.Time) (map[HistoricalKey][]TimestampedMetricValue, error)

	// GetLabeledMetric retrieves the given labeled metric.  Otherwise, it functions identically to GetMetric.
	GetLabeledMetric(metricName string, labels map[string]string, metricKeys []HistoricalKey, start, end time.Time) (map[HistoricalKey][]TimestampedMetricValue, error)

	// GetAggregation fetches the given aggregations for one or more objects (specified by metricKeys) of
	// the same type, within the given time interval, calculated over a series of buckets.  The start time,
	// end time, and bucket size may be zero.  A start time of zero indicates no starting bound, while and
	// end time of zero indicates no ending bound (effectively meaning up to the latest metrics, but not metrics
	// from the future).  A bucket size of zero indicates that only a single bucket spanning the entire specified
	// time range should be returned.
	GetAggregation(metricName string, aggregations []AggregationType, metricKeys []HistoricalKey, start, end time.Time, bucketSize time.Duration) (map[HistoricalKey][]TimestampedAggregationValue, error)

	// GetLabeledAggregation fetches a the given aggregations for a labeled metric instead of a normal metric.
	// Otherwise, it functions identically to GetAggregation.
	GetLabeledAggregation(metricName string, labels map[string]string, aggregations []AggregationType, metricKeys []HistoricalKey, start, end time.Time, bucketSize time.Duration) (map[HistoricalKey][]TimestampedAggregationValue, error)

	// GetMetricNames retrieves the available metric names for the given object
	GetMetricNames(metricKey HistoricalKey) ([]string, error)

	// GetNodes retrieves the list of nodes in the cluster
	GetNodes() ([]string, error)
	// GetNamespaces retrieves the list of namespaces in the cluster
	GetNamespaces() ([]string, error)
	// GetPodsFromNamespace retrieves the list of pods in a given namespace
	GetPodsFromNamespace(namespace string) ([]string, error)
	// GetSystemContainersFromNode retrieves the list of free containers for a given node
	GetSystemContainersFromNode(node string) ([]string, error)
}

type LabelDescriptor struct {
	// Key to use for the label.
	Key string `json:"key,omitempty"`

	// Description of the label.
	Description string `json:"description,omitempty"`
}

type LabeledMetric struct {
	Name   string
	Labels map[string]string
	MetricValue
}

type Metric struct {
	MetricDescriptor

	// Returns whether this metric is present.
	HasValue func(*cadvisor.ContainerSpec) bool

	// Returns a slice of internal point objects that contain metric values and associated labels.
	GetValue func(*cadvisor.ContainerSpec, *cadvisor.ContainerStats) MetricValue

	// Returns whether this metric is present.
	HasLabeledMetric func(*cadvisor.ContainerSpec, *cadvisor.ContainerStats) bool

	// Returns a slice of internal point objects that contain metric values and associated labels.
	GetLabeledMetric func(*cadvisor.ContainerSpec, *cadvisor.ContainerStats) []LabeledMetric
}

type MetricDescriptor struct {
	// The unique name of the metric.
	Name string `json:"name,omitempty"`

	// Description of the metric.
	Description string `json:"description,omitempty"`

	// Descriptor of the labels specific to this metric.
	Labels []LabelDescriptor `json:"labels,omitempty"`

	// Type and value of metric data.
	Type      MetricType `json:"type,omitempty"`
	ValueType ValueType  `json:"value_type,omitempty"`
	Units     UnitsType  `json:"units,omitempty"`
}

type MetricFamily string

type MetricSet struct {
	// CollectionStartTime is a time since when the metrics are collected for this entity.
	// It is affected by events like entity (e.g. pod) creation, entity restart (e.g. for container),
	// Kubelet restart.
	CollectionStartTime time.Time
	// EntityCreateTime is a time of entity creation and persists through entity restarts and
	// Kubelet restarts.
	EntityCreateTime time.Time
	ScrapeTime       time.Time
	MetricValues     map[string]MetricValue
	Labels           map[string]string
	LabeledMetrics   []LabeledMetric
}

type MetricType int8

const (
	MetricCumulative MetricType = iota
	MetricGauge
	MetricDelta
)

type MetricValue struct {
	IntValue   int64
	FloatValue float64
	MetricType MetricType
	ValueType  ValueType
}

type MetricsSource interface {
	Name() string
	ScrapeMetrics(start, end time.Time) (*DataBatch, error)
}

type MetricsSourceProvider interface {
	GetMetricsSources() []MetricsSource
}

type TimestampedAggregationValue struct {
	// Timestamp is the start time of the bucket
	Timestamp time.Time

	// BucketSize is the duration of the bucket
	BucketSize time.Duration

	AggregationValue
}

type TimestampedMetricValue struct {
	MetricValue
	Timestamp time.Time
}

type UnitsType int8

const (
	// A counter metric.
	UnitsCount UnitsType = iota
	// A metric in bytes.
	UnitsBytes
	// A metric in milliseconds.
	UnitsMilliseconds
	// A metric in nanoseconds.
	UnitsNanoseconds
	// A metric in millicores.
	UnitsMillicores
)

type ValueType int8

const (
	ValueInt64 ValueType = iota
	ValueFloat
)