package stdout

import (
	"go.opentelemetry.io/otel"
	"go.opentelemetry.io/otel/exporters/stdout/stdouttrace"
	"go.opentelemetry.io/otel/sdk/resource"
	"go.opentelemetry.io/otel/sdk/trace"
	semconv "go.opentelemetry.io/otel/semconv/v1.12.0"
)

// Init 初始化一个向指定 writer 写数据的 追踪器
func Init(cfg *Config) (*trace.TracerProvider, error) {
	// 填充 stdout 的配置参数
	exp, err := stdouttrace.New(stdouttrace.WithWriter(cfg.writer))
	if err != nil {
		return nil, err
	}

	tp := trace.NewTracerProvider(
		trace.WithBatcher(exp),
		trace.WithResource(res(cfg)),
	)

	otel.SetTracerProvider(tp)
	return tp, nil
}

func res(cfg *Config) *resource.Resource {
	return resource.NewWithAttributes(
		semconv.SchemaURL,
		semconv.ServiceNameKey.String(cfg.serverName),
		semconv.ServiceVersionKey.String(cfg.version),
	)
}