package loop

import (
	"context"

	"git.yeij.top/AskaEth/Cyrene_v2/internal/runtime/trace"
)

// span starts a named span of the given kind when a Tracer is configured, else
// returns a nil no-op span. The returned context carries the span as the current
// one so nested spans chain as children. When a FlowPublisher is configured the
// span's session (threaded via ctx) is stamped as a prop and a running placeholder
// node is published immediately, so the flow graph shows work in flight.
func (l *Loop) span(ctx context.Context, name string, kind trace.SpanKind) (context.Context, *trace.Span) {
	if l.tracer == nil {
		return ctx, nil
	}
	sctx, sp := l.tracer.StartSpan(ctx, name, kind)
	if sid := loopSession(ctx); sid != "" {
		_ = sp.SetProp("session", sid)
		if l.flow != nil {
			l.flow.SpanStarted(sid, sp)
		}
	}
	return sctx, sp
}

// finishSpan closes a span with the given status, ignoring a nil span. After the
// span closes (immutable) the finished record is folded into the flow graph and
// published, flipping the node to its final status.
func (l *Loop) finishSpan(sp *trace.Span, status trace.SpanStatus) {
	if sp == nil {
		return
	}
	sp.Finish(status)
	if l.flow != nil {
		if sid, ok := sp.Props["session"].(string); ok && sid != "" {
			l.flow.SpanFinished(sid, sp)
		}
	}
}

// spanProp attaches a structured property to a span, ignoring a nil span and any
// mutation-after-close error.
func (l *Loop) spanProp(sp *trace.Span, key string, value any) {
	if sp == nil {
		return
	}
	_ = sp.SetProp(key, value)
}