I hate commit messages

files/files.go

@@ -1,15 +1,14 @@
 package files
 
 import (
-	"fmt"
+	"errors"
 	"io"
 	"os"
+	"regexp"
 
 	"github.com/didiercrunch/filou/contract"
 )
 
-var _ = fmt.Print
-
 type encryptor func(reader io.Reader, writer io.Writer, acceptedContract *contract.AcceptedContract) error
 
 type PathEncryptor struct {
@@ -17,7 +16,61 @@ type PathEncryptor struct {
 	EncryptDirectory encryptor
 }
 
-func (this *PathEncryptor) EncryptPath(path string, writer io.Writer, acceptedContract *contract.AcceptedContract) error {
+func (this *PathEncryptor) fileExists(path string) bool {
+	_, err := os.Stat(path)
+	return !os.IsNotExist(err)
+}
+
+func (this *PathEncryptor) getDefaultPathToEncryptFile(originalFileName string) string {
+	isFileWithSingleExtension := regexp.MustCompile(`\.\w+$`)
+	isFileWithDoubleExtension := regexp.MustCompile(`\.\w+\.\w+$`)
+	isHiddenDirectory := regexp.MustCompile(`\/.\w+$`)
+	isHiddenFile := regexp.MustCompile(`\/\.\w+\.\w+$`)
+
+	if isHiddenFile.MatchString(originalFileName) {
+		return isFileWithSingleExtension.ReplaceAllString(originalFileName, ".filou")
+	}
+	if isHiddenDirectory.MatchString(originalFileName) {
+		return originalFileName + ".filou"
+	}
+	if isFileWithDoubleExtension.MatchString(originalFileName) {
+		return isFileWithDoubleExtension.ReplaceAllString(originalFileName, ".filou")
+	}
+	if isFileWithSingleExtension.MatchString(originalFileName) {
+		return isFileWithSingleExtension.ReplaceAllString(originalFileName, ".filou")
+	}
+	return originalFileName + ".filou"
+}
+
+//  create a file with permission set to 600
+func (this *PathEncryptor) createPrivateFile(name string) (*os.File, error) {
+	return os.OpenFile(name, os.O_RDWR|os.O_CREATE|os.O_TRUNC, 0600)
+}
+
+func (this *PathEncryptor) EncryptPathToDefaultFile(path string, acceptedContract *contract.AcceptedContract) error {
+	outputPathName := this.getDefaultPathToEncryptFile(path)
+	if _, err := os.Stat(outputPathName); !os.IsNotExist(err) {
+		return errors.New("the default path to encrypt already exists.")
+	}
+	return nil
+}
+
+func (this *PathEncryptor) EncryptPathToOtherPath(fromPath, toPath string, acceptedContract *contract.AcceptedContract) error {
+	if this.fileExists(toPath) {
+		return errors.New("output file already exists")
+	}
+	if f, err := this.createPrivateFile(toPath); err != nil {
+		return err
+	} else {
+		defer f.Close()
+		return this.EncryptPathToWriter(fromPath, f, acceptedContract)
+	}
+}
+
+func (this *PathEncryptor) EncryptPathToWriter(path string, writer io.Writer, acceptedContract *contract.AcceptedContract) error {
+	if !this.fileExists(path) {
+		return errors.New("input file does not exists")
+	}
 	f, err := os.Open(path)
 	if err != nil {
 		return err