package commands

import (
	"fmt"
	"os"
	"path"

	"github.com/go-git/go-billy/v5"
	"github.com/go-git/go-billy/v5/osfs"
	"github.com/go-git/go-git/v5"
	gitcfg "github.com/go-git/go-git/v5/config"
	"github.com/go-git/go-git/v5/plumbing/cache"
	"github.com/go-git/go-git/v5/storage/filesystem"
)

type TestSetupPaths struct {
	baseTestDirectory  string
	baseTestRepository string
}

func checkErrorDuringPreparation(err error) {
	if err != nil {
		fmt.Printf("Cannot prepare a temporary directory for testing! %v ", err.Error())
		os.Exit(2)
	}
}

func createRepositoryForTest() string {
	systemTMPDirectoryWithTestPath := fmt.Sprintf("%v/grmTest", os.TempDir())
	if _, ok := os.Stat(systemTMPDirectoryWithTestPath); ok != nil {
		err := os.Mkdir(systemTMPDirectoryWithTestPath, 0777)
		checkErrorDuringPreparation(err)
	}
	temporaryDirPath, err := os.MkdirTemp(systemTMPDirectoryWithTestPath, "*")
	checkErrorDuringPreparation(err)
	return temporaryDirPath
}

// prepareRepositoryDirectories - prepare directories for file (rootRepositoryDirectory) and git metadata (gitMetadataDirectory)
func prepareRepositoryDirectories(dirName string) (billy.Filesystem, billy.Filesystem) {
	rootRepositoryDirectory := osfs.New(dirName)
	gitMetadataDirectory, err := rootRepositoryDirectory.Chroot(".git")
	checkErrorDuringPreparation(err)

	return rootRepositoryDirectory, gitMetadataDirectory
}

func prepareBasicRepository() TestSetupPaths {

	temporaryDirPath := createRepositoryForTest()

	// Create an interface of abstraction over filesystem to provide tests over multiple systems
	// baseTestsDirectory - provides to main directory where new directories might be created
	baseTestsDirectory := osfs.New(temporaryDirPath)
	rootRepositoryDirectory, gitMetadataDirectory := prepareRepositoryDirectories(baseTestsDirectory.Root() + "/base_repository")

	repository, err := git.Init(filesystem.NewStorage(
		gitMetadataDirectory,
		cache.NewObjectLRUDefault()),
		rootRepositoryDirectory,
	)
	checkErrorDuringPreparation(err)

	testFile, err := rootRepositoryDirectory.Create("TestFile.txt")
	checkErrorDuringPreparation(err)

	_, err = testFile.Write([]byte("foo-conent"))
	checkErrorDuringPreparation(err)

	repositoryWorkTree, err := repository.Worktree()
	checkErrorDuringPreparation(err)

	_, err = repositoryWorkTree.Add(testFile.Name())
	checkErrorDuringPreparation(err)

	_, err = repositoryWorkTree.Commit("First commit", &git.CommitOptions{})
	checkErrorDuringPreparation(err)

	return TestSetupPaths{
		baseTestDirectory:  baseTestsDirectory.Root(),
		baseTestRepository: rootRepositoryDirectory.Root(),
	}

}

func makeCommit(wk *git.Worktree, commitMessage string) {
	_, err := wk.Commit(commitMessage, &git.CommitOptions{})
	checkErrorDuringPreparation(err)
}

// createAndCloneRepository - create sub-repository with cloned base repository required to verify sync command
func createAndCloneRepository(repositoryName string, paths TestSetupPaths) *git.Repository {

	baseGitRepository, gitMetadataDirectory := prepareRepositoryDirectories(
		path.Join(paths.baseTestDirectory, repositoryName),
	)

	storageForSubRepository := filesystem.NewStorage(gitMetadataDirectory, cache.NewObjectLRUDefault())
	fakeLocalRepository, err := git.Clone(storageForSubRepository, baseGitRepository, &git.CloneOptions{
		URL: paths.baseTestRepository,
	})
	checkErrorDuringPreparation(err)
	return fakeLocalRepository
}

func addLocalRepositoryAsAFakeRemoteRepository(repository *git.Repository, baseTestRepositoryPath string) error {

	_, err := repository.CreateRemote(&gitcfg.RemoteConfig{
		Name: "subremote",
		URLs: []string{baseTestRepositoryPath},
	})
	if err != nil {
		return err
	}
	return repository.Fetch(&git.FetchOptions{
		RemoteName: "subremote",
	})
}