/*
Copyright © contributors to CloudNativePG, established as
CloudNativePG a Series of LF Projects, LLC.

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.

SPDX-License-Identifier: Apache-2.0
*/

package instance

import (
	"context"
	"encoding/json"
	cnpgv1 "github.com/cloudnative-pg/cloudnative-pg/api/v1"
	"github.com/cloudnative-pg/plugin-barman-cloud/internal/cnpgi/metadata"
	"k8s.io/utils/ptr"
	"time"

	"github.com/cloudnative-pg/cnpg-i/pkg/metrics"
	barmancloudv1 "github.com/cloudnative-pg/plugin-barman-cloud/api/v1"
	. "github.com/onsi/ginkgo/v2"
	. "github.com/onsi/gomega"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"
	"sigs.k8s.io/controller-runtime/pkg/client"
	"sigs.k8s.io/controller-runtime/pkg/client/fake"
)

var _ = Describe("Metrics Collect method", func() {
	const (
		clusterName     = "test-cluster"
		namespace       = "test-ns"
		objectStoreName = "test-object-store"
	)

	var (
		fakeClient  client.Client
		m           metricsImpl
		ctx         context.Context
		req         *metrics.CollectMetricsRequest
		objectStore *barmancloudv1.ObjectStore
	)

	BeforeEach(func() {
		ctx = context.Background()
		scheme := runtime.NewScheme()
		Expect(barmancloudv1.AddToScheme(scheme)).To(Succeed())

		// Timestamps for the test
		firstRecoverabilityPoint := metav1.NewTime(time.Now().Add(-24 * time.Hour))
		lastSuccessfulBackupTime := metav1.NewTime(time.Now())

		// Create a fake ObjectStore with a status
		objectStore = &barmancloudv1.ObjectStore{
			ObjectMeta: metav1.ObjectMeta{
				Name:      objectStoreName,
				Namespace: namespace,
			},
			Status: barmancloudv1.ObjectStoreStatus{
				ServerRecoveryWindow: map[string]barmancloudv1.RecoveryWindow{
					clusterName: {
						FirstRecoverabilityPoint: &firstRecoverabilityPoint,
						LastSuccessfulBackupTime: &lastSuccessfulBackupTime,
					},
				},
			},
		}

		// Create a fake client with the ObjectStore
		fakeClient = fake.NewClientBuilder().
			WithScheme(scheme).
			WithStatusSubresource(&barmancloudv1.ObjectStore{}).
			WithObjects(objectStore).
			Build()

		m = metricsImpl{Client: fakeClient}

		// Create a minimal cluster definition
		clusterDefinition := cnpgv1.Cluster{
			ObjectMeta: metav1.ObjectMeta{
				Name:      clusterName,
				Namespace: namespace,
			},
			Spec: cnpgv1.ClusterSpec{
				Plugins: []cnpgv1.PluginConfiguration{
					{
						Name:    metadata.PluginName,
						Enabled: ptr.To(true),
						Parameters: map[string]string{
							"serverName":       clusterName,
							"barmanObjectName": objectStoreName,
						},
					},
				},
			},
		}
		clusterJSON, err := json.Marshal(clusterDefinition)
		Expect(err).ToNot(HaveOccurred())

		req = &metrics.CollectMetricsRequest{
			ClusterDefinition: clusterJSON,
		}
	})

	It("should collect metrics successfully", func() {
		res, err := m.Collect(ctx, req)
		Expect(err).ToNot(HaveOccurred())
		Expect(res).ToNot(BeNil())
		Expect(res.Metrics).To(HaveLen(3))

		// Verify the metrics
		metricsMap := make(map[string]float64)
		for _, metric := range res.Metrics {
			metricsMap[metric.FqName] = metric.Value
		}

		// Check timestamp metrics
		expectedFirstPoint, _ := metricsMap[firstRecoverabilityPointMetricName]
		Expect(expectedFirstPoint).To(BeNumerically("~", float64(objectStore.Status.ServerRecoveryWindow[clusterName].FirstRecoverabilityPoint.Unix()), 1))

		expectedLastBackup, _ := metricsMap[lastAvailableBackupTimestampMetricName]
		Expect(expectedLastBackup).To(BeNumerically("~", float64(objectStore.Status.ServerRecoveryWindow[clusterName].LastSuccessfulBackupTime.Unix()), 1))
	})

	It("should return an error if the object store is not found", func() {
		// Use a client without any objects
		m.Client = fake.NewClientBuilder().Build()
		_, err := m.Collect(ctx, req)
		Expect(err).To(HaveOccurred())
	})
})