// Copyright 2018 Google 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.

package main

import (
	"encoding/json"
	"flag"
	"fmt"
	"io/ioutil"
	"os"
	"path/filepath"
	"testing"

	"github.com/GoogleCloudPlatform/cos-customizer/src/pkg/fs"
	"github.com/GoogleCloudPlatform/cos-customizer/src/pkg/provisioner"

	"github.com/google/go-cmp/cmp"
	"github.com/google/subcommands"
)

func createTempFile(dir string) (string, error) {
	file, err := ioutil.TempFile(dir, "")
	if err != nil {
		return "", err
	}
	if err := file.Close(); err != nil {
		os.Remove(file.Name())
		return "", err
	}
	return file.Name(), nil
}

func setupRunScriptFiles() (string, *fs.Files, error) {
	tmpDir, err := ioutil.TempDir("", "")
	if err != nil {
		return "", nil, err
	}
	files := &fs.Files{}
	files.ProvConfig, err = createTempFile(tmpDir)
	if err != nil {
		os.RemoveAll(tmpDir)
		return "", nil, err
	}
	if err := ioutil.WriteFile(files.ProvConfig, []byte("{}"), 0644); err != nil {
		os.RemoveAll(tmpDir)
		return "", nil, err
	}
	files.UserBuildContextArchive, err = createTempFile(tmpDir)
	if err != nil {
		os.RemoveAll(tmpDir)
		return "", nil, err
	}
	return tmpDir, files, nil
}

func createNonEmptyUserCtxArchive(files *fs.Files, fileName string) error {
	tmpDir, err := ioutil.TempDir("", "")
	if err != nil {
		return err
	}
	defer os.RemoveAll(tmpDir)
	newFile, err := os.Create(filepath.Join(tmpDir, fileName))
	if err != nil {
		return err
	}
	if err := newFile.Close(); err != nil {
		return err
	}
	if err := os.Remove(files.UserBuildContextArchive); err != nil {
		return err
	}
	return fs.CreateBuildContextArchive(newFile.Name(), files.UserBuildContextArchive)
}

func executeRunScript(files *fs.Files, flags ...string) (subcommands.ExitStatus, error) {
	fs := &flag.FlagSet{}
	runScript := &RunScript{}
	runScript.SetFlags(fs)
	if err := fs.Parse(flags); err != nil {
		return 0, err
	}
	ret := runScript.Execute(nil, fs, files)
	if ret != subcommands.ExitSuccess {
		return ret, fmt.Errorf("RunScript failed. input: %v", flags)
	}
	return ret, nil
}

func mustMarshalJSON(t *testing.T, v interface{}) []byte {
	t.Helper()
	data, err := json.Marshal(v)
	if err != nil {
		t.Fatal(err)
	}
	return data
}

func TestRunScript(t *testing.T) {
	var testData = []struct {
		testName       string
		flags          []string
		wantProvConfig provisioner.Config
	}{
		{
			testName: "NoEnv",
			flags:    nil,
			wantProvConfig: provisioner.Config{
				Steps: []provisioner.StepConfig{
					{
						Type: "RunScript",
						Args: mustMarshalJSON(t, &provisioner.RunScriptStep{
							BuildContext: "user",
							Path:         "script",
						}),
					},
				},
			},
		},
		{
			testName: "Env",
			flags:    []string{"-env=HELLO1=world1,HELLO2=world2"},
			wantProvConfig: provisioner.Config{
				Steps: []provisioner.StepConfig{
					{
						Type: "RunScript",
						Args: mustMarshalJSON(t, &provisioner.RunScriptStep{
							BuildContext: "user",
							Path:         "script",
							Env:          "HELLO1=world1,HELLO2=world2",
						}),
					},
				},
			},
		},
	}
	for _, input := range testData {
		t.Run(input.testName, func(t *testing.T) {
			tmpDir, files, err := setupRunScriptFiles()
			if err != nil {
				t.Fatal(err)
			}
			defer os.RemoveAll(tmpDir)
			if err := createNonEmptyUserCtxArchive(files, "script"); err != nil {
				t.Fatal(err)
			}
			if _, err := executeRunScript(files, append(input.flags, "-script=script")...); err != nil {
				t.Fatal(err)
			}
			var provConfig provisioner.Config
			got, err := ioutil.ReadFile(files.ProvConfig)
			if err != nil {
				t.Fatal(err)
			}
			if err := json.Unmarshal(got, &provConfig); err != nil {
				t.Fatal(err)
			}
			if diff := cmp.Diff(provConfig, input.wantProvConfig); diff != "" {
				t.Errorf("run-script(%v): provisioner config mismatch: diff (-got, +want): %s", input.flags, diff)
			}
		})
	}
}

func TestRunScriptBadScript(t *testing.T) {
	var testData = []struct {
		testName string
		flags    []string
	}{
		{
			"BadScript",
			[]string{"-script=script"},
		},
		{
			"NoScript",
			nil,
		},
	}
	for _, input := range testData {
		t.Run(input.testName, func(t *testing.T) {
			tmpDir, files, err := setupRunScriptFiles()
			if err != nil {
				t.Fatal(err)
			}
			defer os.RemoveAll(tmpDir)
			if got, _ := executeRunScript(files, input.flags...); got == subcommands.ExitSuccess {
				t.Errorf("run-script(%v); got subcommands.ExitSuccess, want failure", input.flags)
			}
		})
	}
}