// Copyright 2018 The go-ethereum Authors
// This file is part of go-ethereum.
//
// go-ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// go-ethereum is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with go-ethereum. If not, see <http://www.gnu.org/licenses/>.

// +build linux freebsd

package main

import (
	"bytes"
	"fmt"
	"io"
	"io/ioutil"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"github.com/dexon-foundation/dexon/cmd/utils"
	"github.com/dexon-foundation/dexon/log"
)

type testFile struct {
	filePath string
	content  string
}

// TestCLISwarmFsDefaultIPCPath tests if the most basic fs command, i.e., list
// can find and correctly connect to a running Swarm node on the default
// IPCPath.
func TestCLISwarmFsDefaultIPCPath(t *testing.T) {
	cluster := newTestCluster(t, 1)
	defer cluster.Shutdown()

	handlingNode := cluster.Nodes[0]
	list := runSwarm(t, []string{
		"--datadir", handlingNode.Dir,
		"fs",
		"list",
	}...)

	list.WaitExit()
	if list.Err != nil {
		t.Fatal(list.Err)
	}
}

// TestCLISwarmFs is a high-level test of swarmfs
//
// This test fails on travis for macOS as this executable exits with code 1
// and without any log messages in the log:
// /Library/Filesystems/osxfuse.fs/Contents/Resources/load_osxfuse.
// This is the reason for this file not being built on darwin architecture.
func TestCLISwarmFs(t *testing.T) {
	cluster := newTestCluster(t, 3)
	defer cluster.Shutdown()

	// create a tmp dir
	mountPoint, err := ioutil.TempDir("", "swarm-test")
	log.Debug("swarmfs cli test", "1st mount", mountPoint)
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(mountPoint)

	handlingNode := cluster.Nodes[0]
	mhash := doUploadEmptyDir(t, handlingNode)
	log.Debug("swarmfs cli test: mounting first run", "ipc path", filepath.Join(handlingNode.Dir, handlingNode.IpcPath))

	mount := runSwarm(t, []string{
		fmt.Sprintf("--%s", utils.IPCPathFlag.Name), filepath.Join(handlingNode.Dir, handlingNode.IpcPath),
		"fs",
		"mount",
		mhash,
		mountPoint,
	}...)
	mount.ExpectExit()

	filesToAssert := []*testFile{}

	dirPath, err := createDirInDir(mountPoint, "testSubDir")
	if err != nil {
		t.Fatal(err)
	}
	dirPath2, err := createDirInDir(dirPath, "AnotherTestSubDir")
	if err != nil {
		t.Fatal(err)
	}

	dummyContent := "somerandomtestcontentthatshouldbeasserted"
	dirs := []string{
		mountPoint,
		dirPath,
		dirPath2,
	}
	files := []string{"f1.tmp", "f2.tmp"}
	for _, d := range dirs {
		for _, entry := range files {
			tFile, err := createTestFileInPath(d, entry, dummyContent)
			if err != nil {
				t.Fatal(err)
			}
			filesToAssert = append(filesToAssert, tFile)
		}
	}
	if len(filesToAssert) != len(dirs)*len(files) {
		t.Fatalf("should have %d files to assert now, got %d", len(dirs)*len(files), len(filesToAssert))
	}
	hashRegexp := `[a-f\d]{64}`
	log.Debug("swarmfs cli test: unmounting first run...", "ipc path", filepath.Join(handlingNode.Dir, handlingNode.IpcPath))

	unmount := runSwarm(t, []string{
		fmt.Sprintf("--%s", utils.IPCPathFlag.Name), filepath.Join(handlingNode.Dir, handlingNode.IpcPath),
		"fs",
		"unmount",
		mountPoint,
	}...)
	_, matches := unmount.ExpectRegexp(hashRegexp)
	unmount.ExpectExit()

	hash := matches[0]
	if hash == mhash {
		t.Fatal("this should not be equal")
	}
	log.Debug("swarmfs cli test: asserting no files in mount point")

	//check that there's nothing in the mount folder
	filesInDir, err := ioutil.ReadDir(mountPoint)
	if err != nil {
		t.Fatalf("had an error reading the directory: %v", err)
	}

	if len(filesInDir) != 0 {
		t.Fatal("there shouldn't be anything here")
	}

	secondMountPoint, err := ioutil.TempDir("", "swarm-test")
	log.Debug("swarmfs cli test", "2nd mount point at", secondMountPoint)
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(secondMountPoint)

	log.Debug("swarmfs cli test: remounting at second mount point", "ipc path", filepath.Join(handlingNode.Dir, handlingNode.IpcPath))

	//remount, check files
	newMount := runSwarm(t, []string{
		fmt.Sprintf("--%s", utils.IPCPathFlag.Name), filepath.Join(handlingNode.Dir, handlingNode.IpcPath),
		"fs",
		"mount",
		hash, // the latest hash
		secondMountPoint,
	}...)

	newMount.ExpectExit()
	time.Sleep(1 * time.Second)

	filesInDir, err = ioutil.ReadDir(secondMountPoint)
	if err != nil {
		t.Fatal(err)
	}

	if len(filesInDir) == 0 {
		t.Fatal("there should be something here")
	}

	log.Debug("swarmfs cli test: traversing file tree to see it matches previous mount")

	for _, file := range filesToAssert {
		file.filePath = strings.Replace(file.filePath, mountPoint, secondMountPoint, -1)
		fileBytes, err := ioutil.ReadFile(file.filePath)

		if err != nil {
			t.Fatal(err)
		}
		if !bytes.Equal(fileBytes, bytes.NewBufferString(file.content).Bytes()) {
			t.Fatal("this should be equal")
		}
	}

	log.Debug("swarmfs cli test: unmounting second run", "ipc path", filepath.Join(handlingNode.Dir, handlingNode.IpcPath))

	unmountSec := runSwarm(t, []string{
		fmt.Sprintf("--%s", utils.IPCPathFlag.Name), filepath.Join(handlingNode.Dir, handlingNode.IpcPath),
		"fs",
		"unmount",
		secondMountPoint,
	}...)

	_, matches = unmountSec.ExpectRegexp(hashRegexp)
	unmountSec.ExpectExit()

	if matches[0] != hash {
		t.Fatal("these should be equal - no changes made")
	}
}

func doUploadEmptyDir(t *testing.T, node *testNode) string {
	// create a tmp dir
	tmpDir, err := ioutil.TempDir("", "swarm-test")
	if err != nil {
		t.Fatal(err)
	}
	defer os.RemoveAll(tmpDir)

	hashRegexp := `[a-f\d]{64}`

	flags := []string{
		"--bzzapi", node.URL,
		"--recursive",
		"up",
		tmpDir}

	log.Info("swarmfs cli test: uploading dir with 'swarm up'")
	up := runSwarm(t, flags...)
	_, matches := up.ExpectRegexp(hashRegexp)
	up.ExpectExit()
	hash := matches[0]
	log.Info("swarmfs cli test: dir uploaded", "hash", hash)
	return hash
}

func createDirInDir(createInDir string, dirToCreate string) (string, error) {
	fullpath := filepath.Join(createInDir, dirToCreate)
	err := os.MkdirAll(fullpath, 0777)
	if err != nil {
		return "", err
	}
	return fullpath, nil
}

func createTestFileInPath(dir, filename, content string) (*testFile, error) {
	tFile := &testFile{}
	filePath := filepath.Join(dir, filename)
	if file, err := os.Create(filePath); err == nil {
		tFile.content = content
		tFile.filePath = filePath

		_, err = io.WriteString(file, content)
		if err != nil {
			return nil, err
		}
		file.Close()
	}

	return tFile, nil
}