package fileutils

import (
	"io/ioutil"
	"os"
	"path"
	"testing"
)

// CopyFile with invalid src
func TestCopyFileWithInvalidSrc(t *testing.T) {
	tempFolder, err := ioutil.TempDir("", "docker-fileutils-test")
	defer os.RemoveAll(tempFolder)
	if err != nil {
		t.Fatal(err)
	}
	bytes, err := CopyFile("/invalid/file/path", path.Join(tempFolder, "dest"))
	if err == nil {
		t.Fatal("Should have fail to copy an invalid src file")
	}
	if bytes != 0 {
		t.Fatal("Should have written 0 bytes")
	}

}

// CopyFile with invalid dest
func TestCopyFileWithInvalidDest(t *testing.T) {
	tempFolder, err := ioutil.TempDir("", "docker-fileutils-test")
	defer os.RemoveAll(tempFolder)
	if err != nil {
		t.Fatal(err)
	}
	src := path.Join(tempFolder, "file")
	err = ioutil.WriteFile(src, []byte("content"), 0740)
	if err != nil {
		t.Fatal(err)
	}
	bytes, err := CopyFile(src, path.Join(tempFolder, "/invalid/dest/path"))
	if err == nil {
		t.Fatal("Should have fail to copy an invalid src file")
	}
	if bytes != 0 {
		t.Fatal("Should have written 0 bytes")
	}

}

// CopyFile with same src and dest
func TestCopyFileWithSameSrcAndDest(t *testing.T) {
	tempFolder, err := ioutil.TempDir("", "docker-fileutils-test")
	defer os.RemoveAll(tempFolder)
	if err != nil {
		t.Fatal(err)
	}
	file := path.Join(tempFolder, "file")
	err = ioutil.WriteFile(file, []byte("content"), 0740)
	if err != nil {
		t.Fatal(err)
	}
	bytes, err := CopyFile(file, file)
	if err != nil {
		t.Fatal(err)
	}
	if bytes != 0 {
		t.Fatal("Should have written 0 bytes as it is the same file.")
	}
}

// CopyFile with same src and dest but path is different and not clean
func TestCopyFileWithSameSrcAndDestWithPathNameDifferent(t *testing.T) {
	tempFolder, err := ioutil.TempDir("", "docker-fileutils-test")
	defer os.RemoveAll(tempFolder)
	if err != nil {
		t.Fatal(err)
	}
	testFolder := path.Join(tempFolder, "test")
	err = os.MkdirAll(testFolder, 0740)
	if err != nil {
		t.Fatal(err)
	}
	file := path.Join(testFolder, "file")
	sameFile := testFolder + "/../test/file"
	err = ioutil.WriteFile(file, []byte("content"), 0740)
	if err != nil {
		t.Fatal(err)
	}
	bytes, err := CopyFile(file, sameFile)
	if err != nil {
		t.Fatal(err)
	}
	if bytes != 0 {
		t.Fatal("Should have written 0 bytes as it is the same file.")
	}
}

func TestCopyFile(t *testing.T) {
	tempFolder, err := ioutil.TempDir("", "docker-fileutils-test")
	defer os.RemoveAll(tempFolder)
	if err != nil {
		t.Fatal(err)
	}
	src := path.Join(tempFolder, "src")
	dest := path.Join(tempFolder, "dest")
	ioutil.WriteFile(src, []byte("content"), 0777)
	ioutil.WriteFile(dest, []byte("destContent"), 0777)
	bytes, err := CopyFile(src, dest)
	if err != nil {
		t.Fatal(err)
	}
	if bytes != 7 {
		t.Fatalf("Should have written %d bytes but wrote %d", 7, bytes)
	}
	actual, err := ioutil.ReadFile(dest)
	if err != nil {
		t.Fatal(err)
	}
	if string(actual) != "content" {
		t.Fatalf("Dest content was '%s', expected '%s'", string(actual), "content")
	}
}

// Reading a symlink to a directory must return the directory
func TestReadSymlinkedDirectoryExistingDirectory(t *testing.T) {
	var err error
	if err = os.Mkdir("/tmp/testReadSymlinkToExistingDirectory", 0777); err != nil {
		t.Errorf("failed to create directory: %s", err)
	}

	if err = os.Symlink("/tmp/testReadSymlinkToExistingDirectory", "/tmp/dirLinkTest"); err != nil {
		t.Errorf("failed to create symlink: %s", err)
	}

	var path string
	if path, err = ReadSymlinkedDirectory("/tmp/dirLinkTest"); err != nil {
		t.Fatalf("failed to read symlink to directory: %s", err)
	}

	if path != "/tmp/testReadSymlinkToExistingDirectory" {
		t.Fatalf("symlink returned unexpected directory: %s", path)
	}

	if err = os.Remove("/tmp/testReadSymlinkToExistingDirectory"); err != nil {
		t.Errorf("failed to remove temporary directory: %s", err)
	}

	if err = os.Remove("/tmp/dirLinkTest"); err != nil {
		t.Errorf("failed to remove symlink: %s", err)
	}
}

// Reading a non-existing symlink must fail
func TestReadSymlinkedDirectoryNonExistingSymlink(t *testing.T) {
	var path string
	var err error
	if path, err = ReadSymlinkedDirectory("/tmp/test/foo/Non/ExistingPath"); err == nil {
		t.Fatalf("error expected for non-existing symlink")
	}

	if path != "" {
		t.Fatalf("expected empty path, but '%s' was returned", path)
	}
}

// Reading a symlink to a file must fail
func TestReadSymlinkedDirectoryToFile(t *testing.T) {
	var err error
	var file *os.File

	if file, err = os.Create("/tmp/testReadSymlinkToFile"); err != nil {
		t.Fatalf("failed to create file: %s", err)
	}

	file.Close()

	if err = os.Symlink("/tmp/testReadSymlinkToFile", "/tmp/fileLinkTest"); err != nil {
		t.Errorf("failed to create symlink: %s", err)
	}

	var path string
	if path, err = ReadSymlinkedDirectory("/tmp/fileLinkTest"); err == nil {
		t.Fatalf("ReadSymlinkedDirectory on a symlink to a file should've failed")
	}

	if path != "" {
		t.Fatalf("path should've been empty: %s", path)
	}

	if err = os.Remove("/tmp/testReadSymlinkToFile"); err != nil {
		t.Errorf("failed to remove file: %s", err)
	}

	if err = os.Remove("/tmp/fileLinkTest"); err != nil {
		t.Errorf("failed to remove symlink: %s", err)
	}
}

func TestWildcardMatches(t *testing.T) {
	match, _ := Matches("fileutils.go", []string{"*"})
	if match != true {
		t.Errorf("failed to get a wildcard match, got %v", match)
	}
}

// A simple pattern match should return true.
func TestPatternMatches(t *testing.T) {
	match, _ := Matches("fileutils.go", []string{"*.go"})
	if match != true {
		t.Errorf("failed to get a match, got %v", match)
	}
}

// An exclusion followed by an inclusion should return true.
func TestExclusionPatternMatchesPatternBefore(t *testing.T) {
	match, _ := Matches("fileutils.go", []string{"!fileutils.go", "*.go"})
	if match != true {
		t.Errorf("failed to get true match on exclusion pattern, got %v", match)
	}
}

// A folder pattern followed by an exception should return false.
func TestPatternMatchesFolderExclusions(t *testing.T) {
	match, _ := Matches("docs/README.md", []string{"docs", "!docs/README.md"})
	if match != false {
		t.Errorf("failed to get a false match on exclusion pattern, got %v", match)
	}
}

// A folder pattern followed by an exception should return false.
func TestPatternMatchesFolderWithSlashExclusions(t *testing.T) {
	match, _ := Matches("docs/README.md", []string{"docs/", "!docs/README.md"})
	if match != false {
		t.Errorf("failed to get a false match on exclusion pattern, got %v", match)
	}
}

// A folder pattern followed by an exception should return false.
func TestPatternMatchesFolderWildcardExclusions(t *testing.T) {
	match, _ := Matches("docs/README.md", []string{"docs/*", "!docs/README.md"})
	if match != false {
		t.Errorf("failed to get a false match on exclusion pattern, got %v", match)
	}
}

// A pattern followed by an exclusion should return false.
func TestExclusionPatternMatchesPatternAfter(t *testing.T) {
	match, _ := Matches("fileutils.go", []string{"*.go", "!fileutils.go"})
	if match != false {
		t.Errorf("failed to get false match on exclusion pattern, got %v", match)
	}
}

// A filename evaluating to . should return false.
func TestExclusionPatternMatchesWholeDirectory(t *testing.T) {
	match, _ := Matches(".", []string{"*.go"})
	if match != false {
		t.Errorf("failed to get false match on ., got %v", match)
	}
}

// A single ! pattern should return an error.
func TestSingleExclamationError(t *testing.T) {
	_, err := Matches("fileutils.go", []string{"!"})
	if err == nil {
		t.Errorf("failed to get an error for a single exclamation point, got %v", err)
	}
}

// A string preceded with a ! should return true from Exclusion.
func TestExclusion(t *testing.T) {
	exclusion := Exclusion("!")
	if !exclusion {
		t.Errorf("failed to get true for a single !, got %v", exclusion)
	}
}

// Matches with no patterns
func TestMatchesWithNoPatterns(t *testing.T) {
	matches, err := Matches("/any/path/there", []string{})
	if err != nil {
		t.Fatal(err)
	}
	if matches {
		t.Fatalf("Should not have match anything")
	}
}

// Matches with malformed patterns
func TestMatchesWithMalformedPatterns(t *testing.T) {
	matches, err := Matches("/any/path/there", []string{"["})
	if err == nil {
		t.Fatal("Should have failed because of a malformed syntax in the pattern")
	}
	if matches {
		t.Fatalf("Should not have match anything")
	}
}

// An empty string should return true from Empty.
func TestEmpty(t *testing.T) {
	empty := Empty("")
	if !empty {
		t.Errorf("failed to get true for an empty string, got %v", empty)
	}
}

func TestCleanPatterns(t *testing.T) {
	cleaned, _, _, _ := CleanPatterns([]string{"docs", "config"})
	if len(cleaned) != 2 {
		t.Errorf("expected 2 element slice, got %v", len(cleaned))
	}
}

func TestCleanPatternsStripEmptyPatterns(t *testing.T) {
	cleaned, _, _, _ := CleanPatterns([]string{"docs", "config", ""})
	if len(cleaned) != 2 {
		t.Errorf("expected 2 element slice, got %v", len(cleaned))
	}
}

func TestCleanPatternsExceptionFlag(t *testing.T) {
	_, _, exceptions, _ := CleanPatterns([]string{"docs", "!docs/README.md"})
	if !exceptions {
		t.Errorf("expected exceptions to be true, got %v", exceptions)
	}
}

func TestCleanPatternsLeadingSpaceTrimmed(t *testing.T) {
	_, _, exceptions, _ := CleanPatterns([]string{"docs", "  !docs/README.md"})
	if !exceptions {
		t.Errorf("expected exceptions to be true, got %v", exceptions)
	}
}

func TestCleanPatternsTrailingSpaceTrimmed(t *testing.T) {
	_, _, exceptions, _ := CleanPatterns([]string{"docs", "!docs/README.md  "})
	if !exceptions {
		t.Errorf("expected exceptions to be true, got %v", exceptions)
	}
}

func TestCleanPatternsErrorSingleException(t *testing.T) {
	_, _, _, err := CleanPatterns([]string{"!"})
	if err == nil {
		t.Errorf("expected error on single exclamation point, got %v", err)
	}
}

func TestCleanPatternsFolderSplit(t *testing.T) {
	_, dirs, _, _ := CleanPatterns([]string{"docs/config/CONFIG.md"})
	if dirs[0][0] != "docs" {
		t.Errorf("expected first element in dirs slice to be docs, got %v", dirs[0][1])
	}
	if dirs[0][1] != "config" {
		t.Errorf("expected first element in dirs slice to be config, got %v", dirs[0][1])
	}
}