/*
 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

     https://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 k8sutils

import (
	"bytes"
	"io/ioutil"
	"net/http"
	"os"
	"testing"

	"github.com/stretchr/testify/require"
	corev1 "k8s.io/api/core/v1"
	"k8s.io/apimachinery/pkg/api/meta"
	"k8s.io/apimachinery/pkg/runtime"
	"k8s.io/apimachinery/pkg/runtime/schema"
	"k8s.io/cli-runtime/pkg/genericclioptions"
	"k8s.io/cli-runtime/pkg/resource"
	"k8s.io/client-go/discovery"
	"k8s.io/client-go/dynamic"
	"k8s.io/client-go/rest"
	"k8s.io/client-go/rest/fake"
	"k8s.io/client-go/tools/clientcmd"
	kubeconfig "k8s.io/client-go/tools/clientcmd/api"
	cmdtesting "k8s.io/kubectl/pkg/cmd/testing"
	cmdutil "k8s.io/kubectl/pkg/cmd/util"
	"k8s.io/kubectl/pkg/scheme"
	"k8s.io/kubectl/pkg/util/openapi"
	"k8s.io/kubectl/pkg/validation"
)

// MockKubectlFactory implements Factory interface for testing purposes.
type MockKubectlFactory struct {
	MockToDiscoveryClient     func() (discovery.CachedDiscoveryInterface, error)
	MockDynamicClient         func() (dynamic.Interface, error)
	MockOpenAPISchema         func() (openapi.Resources, error)
	MockValidator             func() (validation.Schema, error)
	MockToRESTMapper          func() (meta.RESTMapper, error)
	MockToRESTConfig          func() (*rest.Config, error)
	MockNewBuilder            func() *resource.Builder
	MockToRawKubeConfigLoader func() clientcmd.ClientConfig
	MockClientForMapping      func() (resource.RESTClient, error)
	KubeConfig                kubeconfig.Config
	genericclioptions.ConfigFlags
	cmdutil.Factory
}

// ToDiscoveryClient implements Factory interface
func (f *MockKubectlFactory) ToDiscoveryClient() (discovery.CachedDiscoveryInterface, error) {
	return f.MockToDiscoveryClient()
}
func (f *MockKubectlFactory) DynamicClient() (dynamic.Interface, error) { return f.MockDynamicClient() }
func (f *MockKubectlFactory) OpenAPISchema() (openapi.Resources, error) { return f.MockOpenAPISchema() }
func (f *MockKubectlFactory) Validator(bool) (validation.Schema, error) {
	return f.MockValidator()
}
func (f *MockKubectlFactory) ToRESTMapper() (meta.RESTMapper, error) { return f.MockToRESTMapper() }
func (f *MockKubectlFactory) ToRESTConfig() (*rest.Config, error)    { return f.MockToRESTConfig() }
func (f *MockKubectlFactory) NewBuilder() *resource.Builder          { return f.MockNewBuilder() }
func (f *MockKubectlFactory) ToRawKubeConfigLoader() clientcmd.ClientConfig {
	return f.MockToRawKubeConfigLoader()
}
func (f *MockKubectlFactory) ClientForMapping(*meta.RESTMapping) (resource.RESTClient, error) {
	return f.MockClientForMapping()
}

func (f *MockKubectlFactory) WithToDiscoveryClientByError(d discovery.CachedDiscoveryInterface,
	err error) *MockKubectlFactory {
	f.MockToDiscoveryClient = func() (discovery.CachedDiscoveryInterface, error) { return d, err }
	return f
}

func (f *MockKubectlFactory) WithOpenAPISchemaByError(r openapi.Resources, err error) *MockKubectlFactory {
	f.MockOpenAPISchema = func() (openapi.Resources, error) { return r, err }
	return f
}

func (f *MockKubectlFactory) WithDynamicClientByError(d dynamic.Interface, err error) *MockKubectlFactory {
	f.MockDynamicClient = func() (dynamic.Interface, error) { return d, err }
	return f
}

func (f *MockKubectlFactory) WithValidatorByError(v validation.Schema, err error) *MockKubectlFactory {
	f.MockValidator = func() (validation.Schema, error) { return v, err }
	return f
}

func (f *MockKubectlFactory) WithToRESTMapperByError(r meta.RESTMapper, err error) *MockKubectlFactory {
	f.MockToRESTMapper = func() (meta.RESTMapper, error) { return r, err }
	return f
}

func (f *MockKubectlFactory) WithToRESTConfigByError(r *rest.Config, err error) *MockKubectlFactory {
	f.MockToRESTConfig = func() (*rest.Config, error) { return r, err }
	return f
}

func (f *MockKubectlFactory) WithNewBuilderByError(r *resource.Builder) *MockKubectlFactory {
	f.MockNewBuilder = func() *resource.Builder { return r }
	return f
}

func (f *MockKubectlFactory) WithToRawKubeConfigLoaderByError(c clientcmd.ClientConfig) *MockKubectlFactory {
	f.MockToRawKubeConfigLoader = func() clientcmd.ClientConfig { return c }
	return f
}

func (f *MockKubectlFactory) WithClientForMappingByError(r resource.RESTClient, err error) *MockKubectlFactory {
	f.MockClientForMapping = func() (resource.RESTClient, error) { return r, err }
	return f
}

func NewMockKubectlFactory() *MockKubectlFactory {
	return &MockKubectlFactory{MockDynamicClient: func() (dynamic.Interface, error) { return nil, nil },
		MockToDiscoveryClient:     func() (discovery.CachedDiscoveryInterface, error) { return nil, nil },
		MockOpenAPISchema:         func() (openapi.Resources, error) { return nil, nil },
		MockValidator:             func() (validation.Schema, error) { return nil, nil },
		MockToRESTMapper:          func() (meta.RESTMapper, error) { return nil, nil },
		MockToRESTConfig:          func() (*rest.Config, error) { return nil, nil },
		MockNewBuilder:            func() *resource.Builder { return nil },
		MockToRawKubeConfigLoader: func() clientcmd.ClientConfig { return nil },
		MockClientForMapping:      func() (resource.RESTClient, error) { return nil, nil },
	}
}

type MockClientConfig struct {
	clientcmd.DirectClientConfig
	MockNamespace func() (string, bool, error)
}

func (c MockClientConfig) Namespace() (string, bool, error) { return c.MockNamespace() }

func (c *MockClientConfig) WithNamespace(s string, b bool, err error) *MockClientConfig {
	c.MockNamespace = func() (string, bool, error) { return s, b, err }
	return c
}

func NewMockClientConfig() *MockClientConfig {
	return &MockClientConfig{
		MockNamespace: func() (string, bool, error) { return "test", false, nil },
	}
}

func NewFakeFactoryForRC(t *testing.T, filenameRC string) *cmdtesting.TestFactory {
	c := scheme.Codecs.LegacyCodec(scheme.Scheme.PrioritizedVersionsAllGroups()...)

	f := cmdtesting.NewTestFactory().WithNamespace("test")

	f.ClientConfigVal = cmdtesting.DefaultClientConfig()

	pathRC := "/namespaces/test/replicationcontrollers/test-rc"
	get := "GET"
	_, rcBytes := readReplicationController(t, filenameRC, c)

	f.UnstructuredClient = &fake.RESTClient{
		GroupVersion:         schema.GroupVersion{Version: "v1"},
		NegotiatedSerializer: resource.UnstructuredPlusDefaultContentConfig().NegotiatedSerializer,
		Client: fake.CreateHTTPClient(func(req *http.Request) (*http.Response, error) {
			switch p, m := req.URL.Path, req.Method; {
			case p == pathRC && m == get:
				bodyRC := ioutil.NopCloser(bytes.NewReader(rcBytes))
				return &http.Response{StatusCode: http.StatusOK,
					Header: cmdtesting.DefaultHeader(),
					Body:   bodyRC}, nil
			case p == "/namespaces/test/replicationcontrollers" && m == get:
				bodyRC := ioutil.NopCloser(bytes.NewReader(rcBytes))
				return &http.Response{StatusCode: http.StatusOK,
					Header: cmdtesting.DefaultHeader(),
					Body:   bodyRC}, nil
			case p == "/namespaces/test/replicationcontrollers/no-match" && m == get:
				return &http.Response{StatusCode: http.StatusNotFound,
					Header: cmdtesting.DefaultHeader(),
					Body:   cmdtesting.ObjBody(c, &corev1.Pod{})}, nil
			case p == "/api/v1/namespaces/test" && m == get:
				return &http.Response{StatusCode: http.StatusOK,
					Header: cmdtesting.DefaultHeader(),
					Body:   cmdtesting.ObjBody(c, &corev1.Namespace{})}, nil
			default:
				t.Fatalf("unexpected request: %#v\n%#v", req.URL, req)
				return nil, nil
			}
		}),
	}
	return f
}

// Below functions are taken from Kubectl library.
// https://github.com/kubernetes/kubectl/blob/master/pkg/cmd/apply/apply_test.go
func readReplicationController(t *testing.T, filenameRC string, c runtime.Codec) (string, []byte) {
	t.Helper()
	rcObj := readReplicationControllerFromFile(t, filenameRC, c)
	metaAccessor, err := meta.Accessor(rcObj)
	require.NoError(t, err, "Could not read replcation controller")
	rcBytes, err := runtime.Encode(c, rcObj)
	require.NoError(t, err, "Could not read replcation controller")
	return metaAccessor.GetName(), rcBytes
}

func readReplicationControllerFromFile(t *testing.T,
	filename string, c runtime.Decoder) *corev1.ReplicationController {
	data := readBytesFromFile(t, filename)
	rc := corev1.ReplicationController{}
	require.NoError(t, runtime.DecodeInto(c, data, &rc), "Could not read replcation controller")

	return &rc
}

func readBytesFromFile(t *testing.T, filename string) []byte {
	file, err := os.Open(filename)
	require.NoError(t, err, "Could not read file")
	defer file.Close()

	data, err := ioutil.ReadAll(file)
	require.NoError(t, err, "Could not read file")

	return data
}