/*
Copyright 2018 Google LLC All Rights Reserved.

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 commands

import (
	"bytes"
	"context"
	"errors"
	"fmt"
	"io"
	"io/ioutil"
	"log"
	"net/http/httptest"
	"path"
	"strings"
	"testing"

	"github.com/docker/docker/api/types"
	"github.com/google/go-cmp/cmp"
	"github.com/google/go-cmp/cmp/cmpopts"
	"github.com/google/go-containerregistry/pkg/crane"
	"github.com/google/go-containerregistry/pkg/name"
	"github.com/google/go-containerregistry/pkg/registry"
	v1 "github.com/google/go-containerregistry/pkg/v1"
	"github.com/google/go-containerregistry/pkg/v1/daemon"
	"github.com/google/go-containerregistry/pkg/v1/empty"
	"github.com/google/go-containerregistry/pkg/v1/random"
	"github.com/google/ko/pkg/build"
	"github.com/google/ko/pkg/commands/options"
	kotesting "github.com/google/ko/pkg/internal/testing"
	"gopkg.in/yaml.v3"
)

var (
	fooRef      = "github.com/awesomesauce/foo"
	foo         = mustRandom()
	fooHash     = mustDigest(foo)
	barRef      = "github.com/awesomesauce/bar"
	bar         = mustRandom()
	barHash     = mustDigest(bar)
	testBuilder = kotesting.NewFixedBuild(map[string]build.Result{
		fooRef: foo,
		barRef: bar,
	})
	testHashes = map[string]v1.Hash{
		fooRef: fooHash,
		barRef: barHash,
	}

	errImageLoad = fmt.Errorf("ImageLoad() error")
	errImageTag  = fmt.Errorf("ImageTag() error")
)

type erroringClient struct {
	daemon.Client
}

func (m *erroringClient) NegotiateAPIVersion(context.Context) {}
func (m *erroringClient) ImageLoad(context.Context, io.Reader, bool) (types.ImageLoadResponse, error) {
	return types.ImageLoadResponse{}, errImageLoad
}
func (m *erroringClient) ImageTag(_ context.Context, _ string, _ string) error {
	return errImageTag
}

func TestResolveMultiDocumentYAMLs(t *testing.T) {
	refs := []string{fooRef, barRef}
	hashes := []v1.Hash{fooHash, barHash}
	base := mustRepository("gcr.io/multi-pass")

	buf := bytes.NewBuffer(nil)
	encoder := yaml.NewEncoder(buf)
	for _, input := range refs {
		if err := encoder.Encode(build.StrictScheme + input); err != nil {
			t.Fatalf("Encode(%v) = %v", input, err)
		}
	}

	inputYAML := buf.Bytes()

	outYAML, err := resolveFile(
		context.Background(),
		yamlToTmpFile(t, buf.Bytes()),
		testBuilder,
		kotesting.NewFixedPublish(base, testHashes),
		&options.SelectorOptions{})

	if err != nil {
		t.Fatalf("ImageReferences(%v) = %v", string(inputYAML), err)
	}

	buf = bytes.NewBuffer(outYAML)
	decoder := yaml.NewDecoder(buf)
	var outStructured []string
	for {
		var output string
		if err := decoder.Decode(&output); err == nil {
			outStructured = append(outStructured, output)
		} else if errors.Is(err, io.EOF) {
			break
		} else {
			t.Errorf("yaml.Unmarshal(%v) = %v", string(outYAML), err)
		}
	}

	expectedStructured := []string{
		kotesting.ComputeDigest(base, refs[0], hashes[0]),
		kotesting.ComputeDigest(base, refs[1], hashes[1]),
	}

	if want, got := len(expectedStructured), len(outStructured); want != got {
		t.Errorf("resolveFile(%v) = %v, want %v", string(inputYAML), got, want)
	}

	if diff := cmp.Diff(expectedStructured, outStructured, cmpopts.EquateEmpty()); diff != "" {
		t.Errorf("resolveFile(%v); (-want +got) = %v", string(inputYAML), diff)
	}
}

func TestResolveMultiDocumentYAMLsWithSelector(t *testing.T) {
	passesSelector := `apiVersion: something/v1
kind: Foo
metadata:
  labels:
    qux: baz
`
	failsSelector := `apiVersion: other/v2
kind: Bar
`
	// Note that this ends in '---', so it in ends in a final null YAML document.
	inputYAML := []byte(fmt.Sprintf("%s---\n%s---", passesSelector, failsSelector))
	base := mustRepository("gcr.io/multi-pass")

	outputYAML, err := resolveFile(
		context.Background(),
		yamlToTmpFile(t, inputYAML),
		testBuilder,
		kotesting.NewFixedPublish(base, testHashes),
		&options.SelectorOptions{
			Selector: "qux=baz",
		})
	if err != nil {
		t.Fatalf("ImageReferences(%v) = %v", string(inputYAML), err)
	}
	if diff := cmp.Diff(passesSelector, string(outputYAML)); diff != "" {
		t.Errorf("resolveFile (-want +got) = %v", diff)
	}
}

func TestNewBuilder(t *testing.T) {
	namespace := "base"
	s, err := registryServerWithImage(namespace)
	if err != nil {
		t.Fatalf("could not create test registry server: %v", err)
	}
	defer s.Close()
	baseImage := fmt.Sprintf("%s/%s", s.Listener.Addr().String(), namespace)

	tests := []struct {
		description             string
		importpath              string
		bo                      *options.BuildOptions
		wantQualifiedImportpath string
		shouldBuildError        bool
	}{
		{
			description: "test app with already qualified import path",
			importpath:  "ko://github.com/google/ko/test",
			bo: &options.BuildOptions{
				BaseImage:        baseImage,
				ConcurrentBuilds: 1,
				Platforms:        []string{"all"},
			},
			wantQualifiedImportpath: "ko://github.com/google/ko/test",
			shouldBuildError:        false,
		},
		{
			description: "programmatic build config",
			importpath:  "./test",
			bo: &options.BuildOptions{
				BaseImage: baseImage,
				BuildConfigs: map[string]build.Config{
					"github.com/google/ko/test": {
						ID: "id-can-be-anything",
						// no easy way to assert on the output, so trigger error to ensure config is picked up
						Flags: []string{"-invalid-flag-should-cause-error"},
					},
				},
				ConcurrentBuilds: 1,
				WorkingDirectory: "../..",
			},
			wantQualifiedImportpath: "ko://github.com/google/ko/test",
			shouldBuildError:        true,
		},
	}
	for _, test := range tests {
		t.Run(test.description, func(t *testing.T) {
			ctx := context.Background()
			builder, err := NewBuilder(ctx, test.bo)
			if err != nil {
				t.Fatalf("NewBuilder(): %v", err)
			}
			qualifiedImportpath, err := builder.QualifyImport(test.importpath)
			if err != nil {
				t.Fatalf("builder.QualifyImport(%s): %v", test.importpath, err)
			}
			if qualifiedImportpath != test.wantQualifiedImportpath {
				t.Fatalf("incorrect qualified import path, got %s, wanted %s", qualifiedImportpath, test.wantQualifiedImportpath)
			}
			_, err = builder.Build(ctx, qualifiedImportpath)
			if err != nil && !test.shouldBuildError {
				t.Fatalf("builder.Build(): %v", err)
			}
			if err == nil && test.shouldBuildError {
				t.Fatalf("expected error got nil")
			}
		})
	}
}

func TestNewPublisherCanPublish(t *testing.T) {
	dockerRepo := "registry.example.com/repo"
	localDomain := "localdomain.example.com/repo"
	importpath := "github.com/google/ko/test"
	tests := []struct {
		description   string
		wantImageName string
		po            *options.PublishOptions
		shouldError   bool
		wantError     error
	}{
		{
			description:   "base import path",
			wantImageName: fmt.Sprintf("%s/%s", dockerRepo, path.Base(importpath)),
			po: &options.PublishOptions{
				BaseImportPaths: true,
				DockerRepo:      dockerRepo,
			},
		},
		{
			description:   "preserve import path",
			wantImageName: fmt.Sprintf("%s/%s", dockerRepo, importpath),
			po: &options.PublishOptions{
				DockerRepo:          dockerRepo,
				PreserveImportPaths: true,
			},
		},
		{
			description:   "override LocalDomain",
			wantImageName: fmt.Sprintf("%s/%s", localDomain, importpath),
			po: &options.PublishOptions{
				Local:               true,
				LocalDomain:         localDomain,
				PreserveImportPaths: true,
				DockerClient:        &kotesting.MockDaemon{},
			},
		},
		{
			description:   "override DockerClient",
			wantImageName: strings.ToLower(fmt.Sprintf("%s/%s", localDomain, importpath)),
			po: &options.PublishOptions{
				DockerClient: &erroringClient{},
				Local:        true,
			},
			shouldError: true,
			wantError:   errImageLoad,
		},
	}
	for _, test := range tests {
		t.Run(test.description, func(t *testing.T) {
			publisher, err := NewPublisher(test.po)
			if err != nil {
				t.Fatalf("NewPublisher(): %v", err)
			}
			defer publisher.Close()
			ref, err := publisher.Publish(context.Background(), empty.Image, build.StrictScheme+importpath)
			if test.shouldError {
				if err == nil || !strings.HasSuffix(err.Error(), test.wantError.Error()) {
					t.Errorf("%s: got error %v, wanted %v", test.description, err, test.wantError)
				}
				return
			}
			if err != nil {
				t.Fatalf("publisher.Publish(): %v", err)
			}
			gotImageName := ref.Context().Name()
			if gotImageName != test.wantImageName {
				t.Errorf("got %s, wanted %s", gotImageName, test.wantImageName)
			}
		})
	}
}

// registryServerWithImage starts a local registry and pushes a random image.
// Use this to speed up tests, by not having to reach out to gcr.io for the default base image.
// The registry uses a NOP logger to avoid spamming test logs.
// Remember to call `defer Close()` on the returned `httptest.Server`.
func registryServerWithImage(namespace string) (*httptest.Server, error) {
	nopLog := log.New(ioutil.Discard, "", 0)
	r := registry.New(registry.Logger(nopLog))
	s := httptest.NewServer(r)
	imageName := fmt.Sprintf("%s/%s", s.Listener.Addr().String(), namespace)
	image, err := random.Image(1024, 1)
	if err != nil {
		return nil, fmt.Errorf("random.Image(): %w", err)
	}
	crane.Push(image, imageName)
	return s, nil
}

func mustRepository(s string) name.Repository {
	n, err := name.NewRepository(s)
	if err != nil {
		panic(err)
	}
	return n
}

func mustDigest(img v1.Image) v1.Hash {
	d, err := img.Digest()
	if err != nil {
		panic(err)
	}
	return d
}

func mustRandom() v1.Image {
	img, err := random.Image(1024, 5)
	if err != nil {
		panic(err)
	}
	return img
}

func yamlToTmpFile(t *testing.T, yaml []byte) string {
	t.Helper()

	tmpfile, err := ioutil.TempFile("", "doc")
	if err != nil {
		t.Fatalf("error creating temp file: %v", err)
	}

	if _, err := tmpfile.Write(yaml); err != nil {
		t.Fatalf("error writing temp file: %v", err)
	}

	if err := tmpfile.Close(); err != nil {
		t.Fatalf("error closing temp file: %v", err)
	}

	return tmpfile.Name()
}