package tracing

import (
	"context"
	"errors"
	"testing"
	"time"

	"go.opentelemetry.io/otel/attribute"
	"go.opentelemetry.io/otel/codes"
	sdktrace "go.opentelemetry.io/otel/sdk/trace"
	"go.opentelemetry.io/otel/sdk/trace/tracetest"
	"k8s.io/apimachinery/pkg/types"
	"sigs.k8s.io/controller-runtime/pkg/reconcile"
)

type fakeReconciler struct {
	res reconcile.Result
	err error
}

func (f *fakeReconciler) Reconcile(context.Context, reconcile.Request) (reconcile.Result, error) {
	return f.res, f.err
}

func TestNewReconciler_spanPerReconcile(t *testing.T) {
	t.Parallel()

	req := reconcile.Request{NamespacedName: types.NamespacedName{Namespace: "default", Name: "p1"}}

	tests := []struct {
		name       string
		inner      *fakeReconciler
		wantStatus codes.Code
		wantAttr   attribute.KeyValue
	}{
		{
			name:       "success records requeue",
			inner:      &fakeReconciler{res: reconcile.Result{RequeueAfter: 10 * time.Second}},
			wantStatus: codes.Ok,
			wantAttr:   attribute.Int64("reconcile.requeue_after_ms", 10_000),
		},
		{
			name:       "error sets error status",
			inner:      &fakeReconciler{err: errors.New("boom")},
			wantStatus: codes.Error,
			wantAttr:   attribute.String("k8s.object.name", "p1"),
		},
	}

	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()
			sr := tracetest.NewSpanRecorder()
			tp := sdktrace.NewTracerProvider(sdktrace.WithSpanProcessor(sr))
			t.Cleanup(func() { _ = tp.Shutdown(context.Background()) })

			r := NewReconciler("Proxy", tc.inner, WithTracerProvider(tp))
			res, err := r.Reconcile(context.Background(), req)
			if res != tc.inner.res || !errors.Is(err, tc.inner.err) {
				t.Fatalf("decorator changed the result: (%v, %v)", res, err)
			}

			ended := sr.Ended()
			if len(ended) != 1 {
				t.Fatalf("got %d spans, want 1", len(ended))
			}
			span := ended[0]
			if span.Name() != "Reconcile Proxy" {
				t.Errorf("span name = %q, want %q", span.Name(), "Reconcile Proxy")
			}
			if span.Status().Code != tc.wantStatus {
				t.Errorf("status = %v, want %v", span.Status().Code, tc.wantStatus)
			}
			found := false
			for _, a := range span.Attributes() {
				if a == tc.wantAttr {
					found = true
				}
			}
			if !found {
				t.Errorf("attribute %v missing in %v", tc.wantAttr, span.Attributes())
			}
		})
	}
}