/*
Copyright 2024 The Knative Authors

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package resolver_test

import (
	"context"
	"fmt"
	"testing"

	"github.com/google/go-cmp/cmp"
	corev1 "k8s.io/api/core/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/types"
	duckv1 "knative.dev/pkg/apis/duck/v1"
	fakedynamicclient "knative.dev/pkg/injection/clients/dynamicclient/fake"
	"knative.dev/pkg/ptr"
	"knative.dev/pkg/resolver"

	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"
	"k8s.io/apimachinery/pkg/runtime/schema"
	"k8s.io/client-go/kubernetes/scheme"
	duckv1alpha1 "knative.dev/pkg/apis/duck/v1alpha1"
	duckv1beta1 "knative.dev/pkg/apis/duck/v1beta1"
	"knative.dev/pkg/client/injection/ducks/duck/v1/authstatus"
	"knative.dev/pkg/tracker"
)

const (
	authenticatableName       = "testsource"
	authenticatableKind       = "Source"
	authenticatableAPIVersion = "duck.knative.dev/v1"
	authenticatableResource   = "sources.duck.knative.dev"

	authenticatable2Name       = "test2-source"
	authenticatable2Kind       = "AnotherSource"
	authenticatable2APIVersion = "duck.knative.dev/v1"
	authenticatable2Resource   = "anothersources.duck.knative.dev"

	unauthenticatableName       = "testunauthenticatable"
	unauthenticatableKind       = "KResource"
	unauthenticatableAPIVersion = "duck.knative.dev/v1alpha1"

	authenticatableServiceAccountName  = "my-service-account"
	authenticatableServiceAccountName1 = "my-service-account-1"
	authenticatableServiceAccountName2 = "my-service-account-2"
	authenticatable2ServiceAccountName = "service-account-of-2nd-authenticatable"
)

func init() {
	// Add types to scheme
	duckv1alpha1.AddToScheme(scheme.Scheme)
	duckv1beta1.AddToScheme(scheme.Scheme)

	scheme.Scheme.AddKnownTypeWithName(
		schema.FromAPIVersionAndKind(unauthenticatableAPIVersion, unauthenticatableKind),
		&unstructured.Unstructured{},
	)
	scheme.Scheme.AddKnownTypeWithName(
		schema.FromAPIVersionAndKind(unauthenticatableAPIVersion, unauthenticatableKind+"List"),
		&unstructured.UnstructuredList{},
	)
	scheme.Scheme.AddKnownTypeWithName(
		schema.FromAPIVersionAndKind(authenticatableAPIVersion, authenticatableKind),
		&unstructured.Unstructured{},
	)
	scheme.Scheme.AddKnownTypeWithName(
		schema.FromAPIVersionAndKind(authenticatableAPIVersion, authenticatableKind+"List"),
		&unstructured.UnstructuredList{},
	)
}

func TestAuthenticatableResolver_AuthStatusFromObjectReference(t *testing.T) {
	tests := []struct {
		name      string
		objects   []runtime.Object
		objectRef *corev1.ObjectReference
		want      *duckv1.AuthStatus
		wantErr   string
	}{
		{
			name:    "nil everything",
			wantErr: "ref is nil",
		}, {
			name: "Valid authenticatable",
			objects: []runtime.Object{
				getAuthenticatable(),
			},
			objectRef: authenticatableRef(),
			want: &duckv1.AuthStatus{
				ServiceAccountName: ptr.String(authenticatableServiceAccountName),
			},
		}, {
			name: "Valid authenticatable in multiple objects",
			objects: []runtime.Object{
				getUnauthenticatable(),
				getAuthenticatable(),
				getAuthenticatable2(),
			},
			objectRef: authenticatable2Ref(),
			want: &duckv1.AuthStatus{
				ServiceAccountName: ptr.String(authenticatable2ServiceAccountName),
			},
		}, {
			name: "Valid authenticatable multiple SAs",
			objects: []runtime.Object{
				getAuthenticatableWithMultipleSAs(),
			},
			objectRef: authenticatableRef(),
			want: &duckv1.AuthStatus{
				ServiceAccountNames: []string{
					authenticatableServiceAccountName1,
					authenticatableServiceAccountName2,
				},
			},
		}, {
			name: "Unauthenticatable",
			objects: []runtime.Object{
				getUnauthenticatable(),
			},
			objectRef: unauthenticatableRef(),
			wantErr:   fmt.Sprintf(".status.auth is missing in object %s/%s", testNS, unauthenticatableName),
		}, {
			name: "Authenticatable not found",
			objects: []runtime.Object{
				getUnauthenticatable(),
			},
			objectRef: authenticatableRef(),
			wantErr:   fmt.Sprintf("failed to get authenticatable %s/%s: failed to get object %s/%s: %s %q not found", testNS, authenticatableName, testNS, authenticatableName, authenticatableResource, authenticatableName),
		},
	}
	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			ctx, _ := fakedynamicclient.With(context.Background(), scheme.Scheme, tt.objects...)
			ctx = authstatus.WithDuck(ctx)
			r := resolver.NewAuthenticatableResolverFromTracker(ctx, tracker.New(func(types.NamespacedName) {}, 0))

			// Run it twice since this should be idempotent. AuthenticatableResolver should
			// not modify the cache's copy.
			_, _ = r.AuthStatusFromObjectReference(tt.objectRef, getAuthenticatable())
			authStatus, gotErr := r.AuthStatusFromObjectReference(tt.objectRef, getAuthenticatable())

			if gotErr != nil {
				if tt.wantErr != "" {
					if got, want := gotErr.Error(), tt.wantErr; got != want {
						t.Errorf("Unexpected error (-want, +got) =\n%s", cmp.Diff(want, got))
					}
				} else {
					t.Error("Unexpected error:", gotErr)
				}
				return
			}

			if got, want := authStatus, tt.want; !cmp.Equal(got, want) {
				t.Errorf("Unexpected object (-want, +got) =\n%s", cmp.Diff(got, want))
			}
		})
	}
}

func getAuthenticatable() *unstructured.Unstructured {
	return &unstructured.Unstructured{
		Object: map[string]interface{}{
			"apiVersion": authenticatableAPIVersion,
			"kind":       authenticatableKind,
			"metadata": map[string]interface{}{
				"namespace": testNS,
				"name":      authenticatableName,
			},
			"status": map[string]interface{}{
				"auth": map[string]interface{}{
					"serviceAccountName": authenticatableServiceAccountName,
				},
			},
		},
	}
}

func getAuthenticatable2() *unstructured.Unstructured {
	return &unstructured.Unstructured{
		Object: map[string]interface{}{
			"apiVersion": authenticatable2APIVersion,
			"kind":       authenticatable2Kind,
			"metadata": map[string]interface{}{
				"namespace": testNS,
				"name":      authenticatable2Name,
			},
			"status": map[string]interface{}{
				"auth": map[string]interface{}{
					"serviceAccountName": authenticatable2ServiceAccountName,
				},
			},
		},
	}
}

func getAuthenticatableWithMultipleSAs() *unstructured.Unstructured {
	return &unstructured.Unstructured{
		Object: map[string]interface{}{
			"apiVersion": authenticatableAPIVersion,
			"kind":       authenticatableKind,
			"metadata": map[string]interface{}{
				"namespace": testNS,
				"name":      authenticatableName,
			},
			"status": map[string]interface{}{
				"auth": map[string]interface{}{
					"serviceAccountNames": []interface{}{
						authenticatableServiceAccountName1,
						authenticatableServiceAccountName2,
					},
				},
			},
		},
	}
}

func getUnauthenticatable() *unstructured.Unstructured {
	return &unstructured.Unstructured{
		Object: map[string]interface{}{
			"apiVersion": unauthenticatableAPIVersion,
			"kind":       unauthenticatableKind,
			"metadata": map[string]interface{}{
				"namespace": testNS,
				"name":      unauthenticatableName,
			},
			"status": map[string]interface{}{
				"something": map[string]interface{}{
					"foo": "bar",
				},
			},
		},
	}
}

func authenticatableRef() *corev1.ObjectReference {
	return &corev1.ObjectReference{
		Kind:       authenticatableKind,
		Name:       authenticatableName,
		APIVersion: authenticatableAPIVersion,
		Namespace:  testNS,
	}
}

func authenticatable2Ref() *corev1.ObjectReference {
	return &corev1.ObjectReference{
		Kind:       authenticatable2Kind,
		Name:       authenticatable2Name,
		APIVersion: authenticatable2APIVersion,
		Namespace:  testNS,
	}
}

func unauthenticatableRef() *corev1.ObjectReference {
	return &corev1.ObjectReference{
		Kind:       unauthenticatableKind,
		Name:       unauthenticatableName,
		APIVersion: unauthenticatableAPIVersion,
		Namespace:  testNS,
	}
}