// returns data points from Win32_PerfRawData_NETFramework_NETCLRMemory
// <add link to documentation here> - Win32_PerfRawData_NETFramework_NETCLRMemory class
package collector

import (
	"github.com/StackExchange/wmi"
	"github.com/prometheus/client_golang/prometheus"
	"github.com/prometheus/common/log"
)

func init() {
	Factories["netframework_clrmemory"] = NewNETFramework_NETCLRMemoryCollector
}

// A NETFramework_NETCLRMemoryCollector is a Prometheus collector for WMI Win32_PerfRawData_NETFramework_NETCLRMemory metrics
type NETFramework_NETCLRMemoryCollector struct {
	AllocatedBytes                     *prometheus.Desc
	FinalizationSurvivors              *prometheus.Desc
	HeapSize                           *prometheus.Desc
	PromotedBytes                      *prometheus.Desc
	NumberGCHandles                    *prometheus.Desc
	NumberCollections                  *prometheus.Desc
	NumberInducedGC                    *prometheus.Desc
	NumberofPinnedObjects              *prometheus.Desc
	NumberofSinkBlocksinuse            *prometheus.Desc
	NumberTotalCommittedBytes          *prometheus.Desc
	NumberTotalreservedBytes           *prometheus.Desc
	TimeinGC                           *prometheus.Desc
	PromotedFinalizationMemoryfromGen0 *prometheus.Desc
	PromotedMemoryfromGen0             *prometheus.Desc
	PromotedMemoryfromGen1             *prometheus.Desc
}

// NewNETFramework_NETCLRMemoryCollector ...
func NewNETFramework_NETCLRMemoryCollector() (Collector, error) {
	const subsystem = "netframework_clrmemory"
	return &NETFramework_NETCLRMemoryCollector{
		AllocatedBytes: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "allocated_bytes_total"),
			"Displays the total number of bytes allocated on the garbage collection heap.",
			[]string{"process"},
			nil,
		),
		FinalizationSurvivors: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "finalization_survivors"),
			"Displays the number of garbage-collected objects that survive a collection because they are waiting to be finalized.",
			[]string{"process"},
			nil,
		),
		HeapSize: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "heap_size_bytes"),
			"Displays the maximum bytes that can be allocated; it does not indicate the current number of bytes allocated.",
			[]string{"process", "area"},
			nil,
		),
		PromotedBytes: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "promoted_bytes"),
			"Displays the bytes that were promoted from the generation to the next one during the last GC. Memory is promoted when it survives a garbage collection.",
			[]string{"process", "area"},
			nil,
		),
		NumberGCHandles: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "number_gc_handles"),
			"Displays the current number of garbage collection handles in use. Garbage collection handles are handles to resources external to the common language runtime and the managed environment.",
			[]string{"process"},
			nil,
		),
		NumberCollections: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "collections_total"),
			"Displays the number of times the generation objects are garbage collected since the application started.",
			[]string{"process", "area"},
			nil,
		),
		NumberInducedGC: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "induced_gc_total"),
			"Displays the peak number of times garbage collection was performed because of an explicit call to GC.Collect.",
			[]string{"process"},
			nil,
		),
		NumberofPinnedObjects: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "number_pinned_objects"),
			"Displays the number of pinned objects encountered in the last garbage collection.",
			[]string{"process"},
			nil,
		),
		NumberofSinkBlocksinuse: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "number_sink_blocksinuse"),
			"Displays the current number of synchronization blocks in use. Synchronization blocks are per-object data structures allocated for storing synchronization information. They hold weak references to managed objects and must be scanned by the garbage collector.",
			[]string{"process"},
			nil,
		),
		NumberTotalCommittedBytes: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "committed_bytes"),
			"Displays the amount of virtual memory, in bytes, currently committed by the garbage collector. Committed memory is the physical memory for which space has been reserved in the disk paging file.",
			[]string{"process"},
			nil,
		),
		NumberTotalreservedBytes: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "reserved_bytes"),
			"Displays the amount of virtual memory, in bytes, currently reserved by the garbage collector. Reserved memory is the virtual memory space reserved for the application when no disk or main memory pages have been used.",
			[]string{"process"},
			nil,
		),
		TimeinGC: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "gc_time_percent"),
			"Displays the percentage of time that was spent performing a garbage collection in the last sample.",
			[]string{"process"},
			nil,
		),
	}, nil
}

// Collect sends the metric values for each metric
// to the provided prometheus Metric channel.
func (c *NETFramework_NETCLRMemoryCollector) Collect(ch chan<- prometheus.Metric) error {
	if desc, err := c.collect(ch); err != nil {
		log.Error("failed collecting win32_perfrawdata_netframework_netclrmemory metrics:", desc, err)
		return err
	}
	return nil
}

type Win32_PerfRawData_NETFramework_NETCLRMemory struct {
	Name string

	AllocatedBytesPersec               uint64
	FinalizationSurvivors              uint64
	Frequency_PerfTime                 uint64
	Gen0heapsize                       uint64
	Gen0PromotedBytesPerSec            uint64
	Gen1heapsize                       uint64
	Gen1PromotedBytesPerSec            uint64
	Gen2heapsize                       uint64
	LargeObjectHeapsize                uint64
	NumberBytesinallHeaps              uint64
	NumberGCHandles                    uint64
	NumberGen0Collections              uint64
	NumberGen1Collections              uint64
	NumberGen2Collections              uint64
	NumberInducedGC                    uint64
	NumberofPinnedObjects              uint64
	NumberofSinkBlocksinuse            uint64
	NumberTotalcommittedBytes          uint64
	NumberTotalreservedBytes           uint64
	PercentTimeinGC                    uint32
	ProcessID                          uint64
	PromotedFinalizationMemoryfromGen0 uint64
	PromotedMemoryfromGen0             uint64
	PromotedMemoryfromGen1             uint64
}

func (c *NETFramework_NETCLRMemoryCollector) collect(ch chan<- prometheus.Metric) (*prometheus.Desc, error) {
	var dst []Win32_PerfRawData_NETFramework_NETCLRMemory
	q := queryAll(&dst)
	if err := wmi.Query(q, &dst); err != nil {
		return nil, err
	}

	for _, process := range dst {

		if process.Name == "_Global_" {
			continue
		}

		ch <- prometheus.MustNewConstMetric(
			c.AllocatedBytes,
			prometheus.CounterValue,
			float64(process.AllocatedBytesPersec),
			process.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.FinalizationSurvivors,
			prometheus.GaugeValue,
			float64(process.FinalizationSurvivors),
			process.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.HeapSize,
			prometheus.GaugeValue,
			float64(process.Gen0heapsize),
			process.Name,
			"Gen0",
		)

		ch <- prometheus.MustNewConstMetric(
			c.PromotedBytes,
			prometheus.GaugeValue,
			float64(process.Gen0PromotedBytesPerSec),
			process.Name,
			"Gen0",
		)

		ch <- prometheus.MustNewConstMetric(
			c.HeapSize,
			prometheus.GaugeValue,
			float64(process.Gen1heapsize),
			process.Name,
			"Gen1",
		)

		ch <- prometheus.MustNewConstMetric(
			c.PromotedBytes,
			prometheus.GaugeValue,
			float64(process.Gen1PromotedBytesPerSec),
			process.Name,
			"Gen1",
		)

		ch <- prometheus.MustNewConstMetric(
			c.HeapSize,
			prometheus.GaugeValue,
			float64(process.Gen2heapsize),
			process.Name,
			"Gen2",
		)

		ch <- prometheus.MustNewConstMetric(
			c.HeapSize,
			prometheus.GaugeValue,
			float64(process.LargeObjectHeapsize),
			process.Name,
			"LOH",
		)

		ch <- prometheus.MustNewConstMetric(
			c.NumberGCHandles,
			prometheus.GaugeValue,
			float64(process.NumberGCHandles),
			process.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.NumberCollections,
			prometheus.CounterValue,
			float64(process.NumberGen0Collections),
			process.Name,
			"Gen0",
		)

		ch <- prometheus.MustNewConstMetric(
			c.NumberCollections,
			prometheus.CounterValue,
			float64(process.NumberGen1Collections),
			process.Name,
			"Gen1",
		)

		ch <- prometheus.MustNewConstMetric(
			c.NumberCollections,
			prometheus.CounterValue,
			float64(process.NumberGen2Collections),
			process.Name,
			"Gen2",
		)

		ch <- prometheus.MustNewConstMetric(
			c.NumberInducedGC,
			prometheus.CounterValue,
			float64(process.NumberInducedGC),
			process.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.NumberofPinnedObjects,
			prometheus.GaugeValue,
			float64(process.NumberofPinnedObjects),
			process.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.NumberofSinkBlocksinuse,
			prometheus.GaugeValue,
			float64(process.NumberofSinkBlocksinuse),
			process.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.NumberTotalCommittedBytes,
			prometheus.GaugeValue,
			float64(process.NumberTotalcommittedBytes),
			process.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.NumberTotalreservedBytes,
			prometheus.GaugeValue,
			float64(process.NumberTotalreservedBytes),
			process.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.TimeinGC,
			prometheus.GaugeValue,
			float64(process.PercentTimeinGC)/float64(process.Frequency_PerfTime),
			process.Name,
		)
	}

	return nil, nil
}
