package collector

import (
	"github.com/go-kit/log"
	"github.com/prometheus/client_golang/prometheus"
	"github.com/yusufpapurcu/wmi"
)

// A MSCluster_NodeCollector is a Prometheus collector for WMI MSCluster_Node metrics
type MSCluster_NodeCollector struct {
	logger log.Logger

	BuildNumber           *prometheus.Desc
	Characteristics       *prometheus.Desc
	DetectedCloudPlatform *prometheus.Desc
	DynamicWeight         *prometheus.Desc
	Flags                 *prometheus.Desc
	MajorVersion          *prometheus.Desc
	MinorVersion          *prometheus.Desc
	NeedsPreventQuorum    *prometheus.Desc
	NodeDrainStatus       *prometheus.Desc
	NodeHighestVersion    *prometheus.Desc
	NodeLowestVersion     *prometheus.Desc
	NodeWeight            *prometheus.Desc
	State                 *prometheus.Desc
	StatusInformation     *prometheus.Desc
}

func newMSCluster_NodeCollector(logger log.Logger) (Collector, error) {
	const subsystem = "mscluster_node"
	return &MSCluster_NodeCollector{
		logger: log.With(logger, "collector", subsystem),
		BuildNumber: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "build_number"),
			"Provides access to the node's BuildNumber property.",
			[]string{"name"},
			nil,
		),
		Characteristics: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "characteristics"),
			"Provides access to the characteristics set for the node.",
			[]string{"name"},
			nil,
		),
		DetectedCloudPlatform: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "detected_cloud_platform"),
			"(DetectedCloudPlatform)",
			[]string{"name"},
			nil,
		),
		DynamicWeight: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "dynamic_weight"),
			"The dynamic vote weight of the node adjusted by dynamic quorum feature.",
			[]string{"name"},
			nil,
		),
		Flags: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "flags"),
			"Provides access to the flags set for the node.",
			[]string{"name"},
			nil,
		),
		MajorVersion: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "major_version"),
			"Provides access to the node's MajorVersion property, which specifies the major portion of the Windows version installed.",
			[]string{"name"},
			nil,
		),
		MinorVersion: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "minor_version"),
			"Provides access to the node's MinorVersion property, which specifies the minor portion of the Windows version installed.",
			[]string{"name"},
			nil,
		),
		NeedsPreventQuorum: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "needs_prevent_quorum"),
			"Whether the cluster service on that node should be started with prevent quorum flag.",
			[]string{"name"},
			nil,
		),
		NodeDrainStatus: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "node_drain_status"),
			"The current node drain status of a node. 0: Not Initiated; 1: In Progress; 2: Completed; 3: Failed",
			[]string{"name"},
			nil,
		),
		NodeHighestVersion: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "node_highest_version"),
			"Provides access to the node's NodeHighestVersion property, which specifies the highest possible version of the cluster service with which the node can join or communicate.",
			[]string{"name"},
			nil,
		),
		NodeLowestVersion: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "node_lowest_version"),
			"Provides access to the node's NodeLowestVersion property, which specifies the lowest possible version of the cluster service with which the node can join or communicate.",
			[]string{"name"},
			nil,
		),
		NodeWeight: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "node_weight"),
			"The vote weight of the node.",
			[]string{"name"},
			nil,
		),
		State: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "state"),
			"Returns the current state of a node. -1: Unknown; 0: Up; 1: Down; 2: Paused; 3: Joining",
			[]string{"name"},
			nil,
		),
		StatusInformation: prometheus.NewDesc(
			prometheus.BuildFQName(Namespace, subsystem, "status_information"),
			"The isolation or quarantine status of the node.",
			[]string{"name"},
			nil,
		),
	}, nil
}

// MSCluster_Node docs:
// - https://docs.microsoft.com/en-us/previous-versions/windows/desktop/cluswmi/mscluster-node
type MSCluster_Node struct {
	Name string

	BuildNumber           uint
	Characteristics       uint
	DetectedCloudPlatform uint
	DynamicWeight         uint
	Flags                 uint
	MajorVersion          uint
	MinorVersion          uint
	NeedsPreventQuorum    uint
	NodeDrainStatus       uint
	NodeHighestVersion    uint
	NodeLowestVersion     uint
	NodeWeight            uint
	State                 uint
	StatusInformation     uint
}

// Collect sends the metric values for each metric
// to the provided prometheus Metric channel.
func (c *MSCluster_NodeCollector) Collect(ctx *ScrapeContext, ch chan<- prometheus.Metric) error {
	var dst []MSCluster_Node
	q := queryAll(&dst, c.logger)
	if err := wmi.QueryNamespace(q, &dst, "root/MSCluster"); err != nil {
		return err
	}

	for _, v := range dst {

		ch <- prometheus.MustNewConstMetric(
			c.BuildNumber,
			prometheus.GaugeValue,
			float64(v.BuildNumber),
			v.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.Characteristics,
			prometheus.GaugeValue,
			float64(v.Characteristics),
			v.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.DetectedCloudPlatform,
			prometheus.GaugeValue,
			float64(v.DetectedCloudPlatform),
			v.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.DynamicWeight,
			prometheus.GaugeValue,
			float64(v.DynamicWeight),
			v.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.Flags,
			prometheus.GaugeValue,
			float64(v.Flags),
			v.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.MajorVersion,
			prometheus.GaugeValue,
			float64(v.MajorVersion),
			v.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.MinorVersion,
			prometheus.GaugeValue,
			float64(v.MinorVersion),
			v.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.NeedsPreventQuorum,
			prometheus.GaugeValue,
			float64(v.NeedsPreventQuorum),
			v.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.NodeDrainStatus,
			prometheus.GaugeValue,
			float64(v.NodeDrainStatus),
			v.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.NodeHighestVersion,
			prometheus.GaugeValue,
			float64(v.NodeHighestVersion),
			v.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.NodeLowestVersion,
			prometheus.GaugeValue,
			float64(v.NodeLowestVersion),
			v.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.NodeWeight,
			prometheus.GaugeValue,
			float64(v.NodeWeight),
			v.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.State,
			prometheus.GaugeValue,
			float64(v.State),
			v.Name,
		)

		ch <- prometheus.MustNewConstMetric(
			c.StatusInformation,
			prometheus.GaugeValue,
			float64(v.StatusInformation),
			v.Name,
		)
	}

	return nil
}