/*
Copyright 2018 The Kubernetes 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 upgrade

import (
	"fmt"
	"io/ioutil"
	"os"
	"testing"

	"github.com/pkg/errors"
	kubeadmapiv1 "k8s.io/kubernetes/cmd/kubeadm/app/apis/kubeadm/v1beta3"
	"k8s.io/kubernetes/cmd/kubeadm/app/constants"
)

func createTestRunDiffFile(contents []byte) (string, error) {
	file, err := ioutil.TempFile("", "kubeadm-upgrade-diff-config-*.yaml")
	if err != nil {
		return "", errors.Wrap(err, "failed to create temporary test file")
	}
	if _, err := file.Write([]byte(contents)); err != nil {
		return "", errors.Wrap(err, "failed to write to temporary test file")
	}
	if err := file.Close(); err != nil {
		return "", errors.Wrap(err, "failed to close temporary test file")
	}
	return file.Name(), nil
}

func TestRunDiff(t *testing.T) {
	currentVersion := "v" + constants.CurrentKubernetesVersion.String()

	// create a temporary file with valid ClusterConfiguration
	testUpgradeDiffConfigContents := []byte(fmt.Sprintf("apiVersion: %s\n"+
		"kind: ClusterConfiguration\n"+
		"kubernetesVersion: %s", kubeadmapiv1.SchemeGroupVersion.String(), currentVersion))
	testUpgradeDiffConfig, err := createTestRunDiffFile(testUpgradeDiffConfigContents)
	if err != nil {
		t.Fatal(err)
	}
	defer os.Remove(testUpgradeDiffConfig)

	// create a temporary manifest file with dummy contents
	testUpgradeDiffManifestContents := []byte("some-contents")
	testUpgradeDiffManifest, err := createTestRunDiffFile(testUpgradeDiffManifestContents)
	if err != nil {
		t.Fatal(err)
	}
	defer os.Remove(testUpgradeDiffManifest)

	flags := &diffFlags{
		cfgPath: "",
		out:     ioutil.Discard,
	}

	// TODO: Add test cases for empty cfgPath, it should automatically fetch cfg from cluster
	testCases := []struct {
		name            string
		args            []string
		setManifestPath bool
		manifestPath    string
		cfgPath         string
		expectedError   bool
	}{
		{
			name:            "valid: run diff on valid manifest path",
			cfgPath:         testUpgradeDiffConfig,
			setManifestPath: true,
			manifestPath:    testUpgradeDiffManifest,
			expectedError:   false,
		},
		{
			name:          "invalid: missing config file",
			cfgPath:       "missing-path-to-a-config",
			expectedError: true,
		},
		{
			name:            "invalid: valid config but empty manifest path",
			cfgPath:         testUpgradeDiffConfig,
			setManifestPath: true,
			manifestPath:    "",
			expectedError:   true,
		},
		{
			name:            "invalid: valid config but bad manifest path",
			cfgPath:         testUpgradeDiffConfig,
			setManifestPath: true,
			manifestPath:    "bad-path",
			expectedError:   true,
		},
		{
			name:          "invalid: badly formatted version as argument",
			cfgPath:       testUpgradeDiffConfig,
			args:          []string{"bad-version"},
			expectedError: true,
		},
	}

	for _, tc := range testCases {
		t.Run(tc.name, func(t *testing.T) {
			flags.cfgPath = tc.cfgPath
			if tc.setManifestPath {
				flags.apiServerManifestPath = tc.manifestPath
				flags.controllerManagerManifestPath = tc.manifestPath
				flags.schedulerManifestPath = tc.manifestPath
			}
			if err := runDiff(flags, tc.args); (err != nil) != tc.expectedError {
				t.Fatalf("expected error: %v, saw: %v, error: %v", tc.expectedError, (err != nil), err)
			}
		})
	}
}