/*
 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 repo

import (
	"testing"

	"github.com/go-git/go-billy/v5/memfs"
	fixtures "github.com/go-git/go-git-fixtures/v4"
	"github.com/go-git/go-git/v5"
	"github.com/go-git/go-git/v5/plumbing"
	"github.com/go-git/go-git/v5/plumbing/transport"
	"github.com/go-git/go-git/v5/storage/memory"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"opendev.org/airship/airshipctl/testutil"
)

type mockBuilder struct {
	CloneOptions    *git.CloneOptions
	AuthMethod      transport.AuthMethod
	CheckoutOptions *git.CheckoutOptions
	FetchOptions    *git.FetchOptions
	URLString       string
	AuthError       error
}

func (md mockBuilder) ToAuth() (transport.AuthMethod, error) {
	return md.AuthMethod, md.AuthError
}
func (md mockBuilder) ToCloneOptions(transport.AuthMethod) *git.CloneOptions {
	return md.CloneOptions
}
func (md mockBuilder) ToCheckoutOptions(bool) *git.CheckoutOptions {
	return md.CheckoutOptions
}
func (md mockBuilder) ToFetchOptions(transport.AuthMethod) *git.FetchOptions {
	return md.FetchOptions
}
func (md mockBuilder) URL() string { return md.URLString }

func TestDownload(t *testing.T) {
	defer testutil.CleanUpGitFixtures(t)

	fx := fixtures.Basic().One()
	builder := &mockBuilder{
		CheckoutOptions: &git.CheckoutOptions{
			Branch: plumbing.Master,
		},
		CloneOptions: &git.CloneOptions{
			URL: fx.DotGit().Root(),
		},
		URLString: fx.DotGit().Root(),
	}

	fs := memfs.New()
	s := memory.NewStorage()

	repo, err := NewRepository(".", builder)
	require.NoError(t, err)
	repo.Driver.SetFilesystem(fs)
	repo.Driver.SetStorer(s)

	err = repo.Download(false)
	assert.NoError(t, err)

	// This should try to open the repo because it is already downloaded
	repoOpen, err := NewRepository(".", builder)
	require.NoError(t, err)
	repoOpen.Driver.SetFilesystem(fs)
	repoOpen.Driver.SetStorer(s)
	err = repoOpen.Download(false)
	assert.NoError(t, err)
	ref, err := repo.Driver.Head()
	require.NoError(t, err)
	assert.NotNil(t, ref.String())
}

func TestUpdate(t *testing.T) {
	defer testutil.CleanUpGitFixtures(t)

	fx := fixtures.Basic().One()

	checkout := &git.CheckoutOptions{
		Branch: plumbing.Master,
	}
	builder := &mockBuilder{
		CheckoutOptions: checkout,
		CloneOptions: &git.CloneOptions{
			URL: fx.DotGit().Root(),
		},
		FetchOptions: &git.FetchOptions{Auth: nil},
		AuthMethod:   nil,
		URLString:    fx.DotGit().Root(),
	}

	repo, err := NewRepository(".", builder)
	require.NoError(t, err)
	driver := &GitDriver{
		Filesystem: memfs.New(),
		Storer:     memory.NewStorage(),
	}
	// Set inmemory fs instead of real one
	repo.Driver = driver
	require.NoError(t, err)

	// Clone repo into memory fs
	err = repo.Clone()
	require.NoError(t, err)
	// Get hash of the HEAD
	ref, err := repo.Driver.Head()
	require.NoError(t, err)
	headHash := ref.Hash()

	// calculate previous commit hash
	prevCommitHash, err := repo.Driver.ResolveRevision("HEAD~1")
	require.NoError(t, err)
	require.NotEqual(t, prevCommitHash.String(), headHash.String())
	builder.CheckoutOptions = &git.CheckoutOptions{Hash: *prevCommitHash}
	// Checkout previous commit
	err = repo.Checkout(true)
	require.NoError(t, err)

	// Set checkout back to master
	builder.CheckoutOptions = checkout
	err = repo.Checkout(true)
	assert.NoError(t, err)
	// update repository
	require.NoError(t, repo.Update(true))

	currentHash, err := repo.Driver.Head()
	assert.NoError(t, err)
	// Make sure that current has is same as master hash
	assert.Equal(t, headHash.String(), currentHash.Hash().String())

	repo.Driver.Close()
	updateError := repo.Update(true)
	assert.Error(t, updateError)
}

func TestOpen(t *testing.T) {
	defer testutil.CleanUpGitFixtures(t)

	fx := fixtures.Basic().One()
	url := fx.DotGit().Root()
	checkout := &git.CheckoutOptions{Branch: plumbing.Master}
	builder := &mockBuilder{
		CheckoutOptions: checkout,
		URLString:       url,
		CloneOptions:    &git.CloneOptions{Auth: nil, URL: url},
	}

	repo, err := NewRepository(".", builder)
	require.NoError(t, err)
	repo.Driver = &GitDriver{
		Filesystem: memfs.New(),
		Storer:     memory.NewStorage(),
	}

	err = repo.Clone()
	assert.NotNil(t, repo.Driver)
	require.NoError(t, err)

	// This should open the repo
	repoOpen, err := NewRepository(".", builder)
	require.NoError(t, err)

	storer := memory.NewStorage()
	err = storer.SetReference(plumbing.NewReferenceFromStrings("HEAD", ""))
	require.NoError(t, err)
	repoOpen.Driver = &GitDriver{
		Filesystem: memfs.New(),
		Storer:     storer,
	}

	require.NoError(t, repoOpen.Open())
	ref, err := repo.Driver.Head()
	assert.NoError(t, err)
	assert.NotNil(t, ref.String())
}

func TestCheckout(t *testing.T) {
	defer testutil.CleanUpGitFixtures(t)

	fx := fixtures.Basic().One()
	url := fx.DotGit().Root()
	checkout := &git.CheckoutOptions{Branch: plumbing.Master}
	builder := &mockBuilder{
		CheckoutOptions: checkout,
		URLString:       url,
		CloneOptions:    &git.CloneOptions{Auth: nil, URL: url},
	}

	repo, err := NewRepository(".", builder)
	require.NoError(t, err)
	err = repo.Checkout(true)
	assert.Error(t, err)
}