package observability

import (
	"context"

	"skeleton/config"

	"go.opentelemetry.io/otel"
	"go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp"
	"go.opentelemetry.io/otel/propagation"
	"go.opentelemetry.io/otel/sdk/resource"
	sdktrace "go.opentelemetry.io/otel/sdk/trace"
	semconv "go.opentelemetry.io/otel/semconv/v1.34.0"
)

func InitTracing(ctx context.Context, cfg config.ObservabilityConfig) (func(context.Context) error, error) {
	if !cfg.TracingEnabled {
		return func(context.Context) error { return nil }, nil
	}

	options := []otlptracehttp.Option{otlptracehttp.WithEndpoint(cfg.TracingEndpoint)}
	if cfg.TracingInsecure {
		options = append(options, otlptracehttp.WithInsecure())
	}
	exporter, err := otlptracehttp.New(ctx, options...)
	if err != nil {
		return nil, err
	}
	res, err := resource.New(ctx, resource.WithAttributes(semconv.ServiceName(cfg.TracingService)))
	if err != nil {
		return nil, err
	}
	provider := sdktrace.NewTracerProvider(sdktrace.WithBatcher(exporter), sdktrace.WithResource(res))
	otel.SetTracerProvider(provider)
	otel.SetTextMapPropagator(propagation.NewCompositeTextMapPropagator(
		propagation.TraceContext{}, propagation.Baggage{},
	))
	return provider.Shutdown, nil
}