package main

import (
	"context"
	"log"
	"time"

	"go.opentelemetry.io/otel"
	"go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc"
	"go.opentelemetry.io/otel/metric"
	sdkmetric "go.opentelemetry.io/otel/sdk/metric"
	"go.opentelemetry.io/otel/sdk/resource"
	semconv "go.opentelemetry.io/otel/semconv/v1.24.0"
	"google.golang.org/grpc"
	"google.golang.org/grpc/credentials/insecure"
)

func main() {
	ctx := context.Background()

	conn, err := grpc.NewClient("localhost:4317", grpc.WithTransportCredentials(insecure.NewCredentials()))
	if err != nil {
		log.Fatalf("Failed to create gRPC connection: %v", err)
	}
	defer conn.Close()

	exporter, err := otlpmetricgrpc.New(ctx, otlpmetricgrpc.WithGRPCConn(conn))
	if err != nil {
		log.Fatalf("Failed to create OTLP exporter: %v", err)
	}

	res, err := resource.New(ctx, resource.WithAttributes(
		semconv.ServiceNameKey.String("histogram-test"),
		semconv.ServiceVersionKey.String("1.0.0"),
	))
	if err != nil {
		log.Fatalf("Failed to create resource: %v", err)
	}

	meterProvider := sdkmetric.NewMeterProvider(
		sdkmetric.WithReader(sdkmetric.NewPeriodicReader(exporter, sdkmetric.WithInterval(5*time.Second))),
		sdkmetric.WithResource(res),
	)
	defer func() {
		if err := meterProvider.Shutdown(ctx); err != nil {
			log.Printf("Error shutting down meter provider: %v", err)
		}
	}()

	otel.SetMeterProvider(meterProvider)

	meter := otel.Meter("test-meter")
	histogram, err := meter.Float64Histogram("gen",
		metric.WithDescription("Test histogram for merge_histogram_buckets function"),
		metric.WithExplicitBucketBoundaries(1, 2, 3, 4),
	)
	if err != nil {
		log.Fatalf("Failed to create histogram: %v", err)
	}

	// Record 1 value in (-inf,1] bucket
	histogram.Record(ctx, 0.5)

	// Record 2 values in (1,2] bucket
	histogram.Record(ctx, 1.5)
	histogram.Record(ctx, 1.8)

	// Record 3 values in (2,3] bucket
	histogram.Record(ctx, 2.1)
	histogram.Record(ctx, 2.5)
	histogram.Record(ctx, 2.9)

	// Record 4 values in (3,4] bucket
	histogram.Record(ctx, 3.1)
	histogram.Record(ctx, 3.3)
	histogram.Record(ctx, 3.7)
	histogram.Record(ctx, 3.9)

	select {}
}