package metrics

import (
	"context"

	logging "github.com/ipfs/go-log"
	"go.opencensus.io/stats"
	"go.opencensus.io/stats/view"
	"go.opencensus.io/tag"
)

var log = logging.Logger("metrics")

var (
	Messages            = stats.Int64("node_messages", "Number of messages received", stats.UnitDimensionless)
	Peers               = stats.Int64("peers", "Number of connected peers", stats.UnitDimensionless)
	Dials               = stats.Int64("dials", "Number of peer dials", stats.UnitDimensionless)
	StoreMessages       = stats.Int64("store_messages", "Number of historical messages", stats.UnitDimensionless)
	FilterSubscriptions = stats.Int64("filter_subscriptions", "Number of filter subscriptions", stats.UnitDimensionless)
	StoreErrors         = stats.Int64("errors", "Number of errors in store protocol", stats.UnitDimensionless)
	LightpushErrors     = stats.Int64("errors", "Number of errors in lightpush protocol", stats.UnitDimensionless)
)

var (
	KeyType, _   = tag.NewKey("type")
	ErrorType, _ = tag.NewKey("error_type")
)

var (
	PeersView = &view.View{
		Name:        "gowaku_connected_peers",
		Measure:     Peers,
		Description: "Number of connected peers",
		Aggregation: view.Sum(),
	}
	DialsView = &view.View{
		Name:        "gowaku_peers_dials",
		Measure:     Dials,
		Description: "Number of peer dials",
		Aggregation: view.Count(),
	}
	MessageView = &view.View{
		Name:        "gowaku_node_messages",
		Measure:     Messages,
		Description: "The number of the messages received",
		Aggregation: view.Count(),
	}
	StoreMessagesView = &view.View{
		Name:        "gowaku_store_messages",
		Measure:     StoreMessages,
		Description: "The distribution of the store protocol messages",
		Aggregation: view.LastValue(),
		TagKeys:     []tag.Key{KeyType},
	}
	FilterSubscriptionsView = &view.View{
		Name:        "gowaku_filter_subscriptions",
		Measure:     FilterSubscriptions,
		Description: "The number of content filter subscriptions",
		Aggregation: view.LastValue(),
	}
	StoreErrorTypesView = &view.View{
		Name:        "gowaku_store_errors",
		Measure:     StoreErrors,
		Description: "The distribution of the store protocol errors",
		Aggregation: view.Count(),
		TagKeys:     []tag.Key{KeyType},
	}
	LightpushErrorTypesView = &view.View{
		Name:        "gowaku_lightpush_errors",
		Measure:     LightpushErrors,
		Description: "The distribution of the lightpush protocol errors",
		Aggregation: view.Count(),
		TagKeys:     []tag.Key{KeyType},
	}
)

func RecordLightpushError(ctx context.Context, tagType string) {
	if err := stats.RecordWithTags(ctx, []tag.Mutator{tag.Insert(tag.Key(ErrorType), tagType)}, LightpushErrors.M(1)); err != nil {
		log.Error("failed to record with tags", err)
	}
}

func RecordMessage(ctx context.Context, tagType string, len int) {
	if err := stats.RecordWithTags(ctx, []tag.Mutator{tag.Insert(KeyType, tagType)}, StoreMessages.M(int64(len))); err != nil {
		log.Error("failed to record with tags", err)
	}
}

func RecordStoreError(ctx context.Context, tagType string) {
	if err := stats.RecordWithTags(ctx, []tag.Mutator{tag.Insert(ErrorType, tagType)}, StoreErrors.M(1)); err != nil {
		log.Error("failed to record with tags", err)
	}
}