package controller

import (
	"context"
	"testing"

	corev1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	clientgoscheme "k8s.io/client-go/kubernetes/scheme"
	"sigs.k8s.io/controller-runtime/pkg/client/fake"

	bindv1alpha1 "git.unkin.net/unkin/bind-operator/api/v1alpha1"
)

func TestConfigHashStableAndSensitive(t *testing.T) {
	scheme := runtime.NewScheme()
	if err := clientgoscheme.AddToScheme(scheme); err != nil {
		t.Fatal(err)
	}
	if err := bindv1alpha1.AddToScheme(scheme); err != nil {
		t.Fatal(err)
	}
	cluster := &bindv1alpha1.BindCluster{ObjectMeta: metav1.ObjectMeta{Name: "c", Namespace: "ns"}}
	cm := &corev1.ConfigMap{
		ObjectMeta: metav1.ObjectMeta{Name: configMapName("c"), Namespace: "ns"},
		Data:       map[string]string{"named.conf.secondary": "options { recursion yes; };"},
	}
	keys := &corev1.Secret{
		ObjectMeta: metav1.ObjectMeta{Name: keysSecretName("c"), Namespace: "ns"},
		Data:       map[string][]byte{"keys.conf": []byte("key x {};")},
	}
	c := fake.NewClientBuilder().WithScheme(scheme).WithObjects(cm, keys).Build()
	r := &BindClusterReconciler{Client: c, Scheme: scheme}
	ctx := context.Background()

	h1 := r.configHash(ctx, cluster)
	if h1 == "" {
		t.Fatal("hash should not be empty when config exists")
	}
	// Stable across calls when nothing changes.
	if h2 := r.configHash(ctx, cluster); h2 != h1 {
		t.Fatalf("hash not stable: %s != %s", h1, h2)
	}

	// A config change flips the hash (this is what rolls the StatefulSet).
	cm.Data["named.conf.secondary"] = "options { recursion yes; validate-except { unkin.net; }; };"
	if err := c.Update(ctx, cm); err != nil {
		t.Fatal(err)
	}
	if h3 := r.configHash(ctx, cluster); h3 == h1 {
		t.Fatal("hash must change when the ConfigMap changes")
	}

	// A TSIG key (keys.conf) change also flips it.
	afterCM := r.configHash(ctx, cluster)
	keys.Data["keys.conf"] = []byte("key x { algorithm hmac-sha256; };")
	if err := c.Update(ctx, keys); err != nil {
		t.Fatal(err)
	}
	if h4 := r.configHash(ctx, cluster); h4 == afterCM {
		t.Fatal("hash must change when keys.conf changes")
	}
}