// Copyright The OpenTelemetry Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// Command jaeger is an example program that creates spans
// and uploads to Jaeger.
package main

import (
	"context"
	"log"

	"go.opentelemetry.io/otel"
	"go.opentelemetry.io/otel/sdk/resource"
	"go.opentelemetry.io/otel/semconv"

	"go.opentelemetry.io/otel/attribute"
	"go.opentelemetry.io/otel/exporters/trace/jaeger"
	sdktrace "go.opentelemetry.io/otel/sdk/trace"
)

// initTracer creates a new trace provider instance and registers it as global trace provider.
func initTracer() func() {
	// Create and install Jaeger export pipeline.
	flush, err := jaeger.InstallNewPipeline(
		jaeger.WithCollectorEndpoint("http://localhost:14268/api/traces"),
		jaeger.WithSDK(&sdktrace.Config{
			DefaultSampler: sdktrace.AlwaysSample(),
			Resource: resource.NewWithAttributes(
				semconv.ServiceNameKey.String("trace-demo"),
				attribute.String("exporter", "jaeger"),
				attribute.Float64("float", 312.23),
			),
		}),
	)
	if err != nil {
		log.Fatal(err)
	}
	return flush
}

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

	flush := initTracer()
	defer flush()

	tr := otel.Tracer("component-main")
	ctx, span := tr.Start(ctx, "foo")
	defer span.End()

	bar(ctx)
}

func bar(ctx context.Context) {
	tr := otel.Tracer("component-bar")
	_, span := tr.Start(ctx, "bar")
	span.SetAttributes(attribute.Key("testset").String("value"))
	defer span.End()

	// Do bar...
}