Closes #217. Use XDG-compatible config directory

This change is largely experimental and it's entirely possible it could
wipe out your existing configuration. Be warned.

Old config path was: ~/.wtf/
New config path is:  ~/.config/wtf/

If an existing config directory already exists, this change attempts to
copy it to the new location.

Note that if your config file contains paths to files in the old config
directory, they won't work. You'll need to change them by hand.

cfg/config_files.go

@@ -6,11 +6,53 @@ import (
 	"os"
 
 	"github.com/olebedev/config"
+	"github.com/senorprogrammer/wtf/logger"
 	"github.com/senorprogrammer/wtf/wtf"
 )
 
+const CONFIG_DIR_V1 = "~/.wtf/"
+const CONFIG_DIR_V2 = "~/.config/wtf/"
+
+/* -------------------- Config Migration -------------------- */
+
+// MigrateOldConfig copies any existing configuration from the old location
+// to the new, XDG-compatible location
+func MigrateOldConfig() {
+	srcDir, _ := wtf.ExpandHomeDir(CONFIG_DIR_V1)
+	destDir, _ := wtf.ExpandHomeDir(CONFIG_DIR_V2)
+
+	// If the old config directory doesn't exist, do not move
+	if _, err := os.Stat(srcDir); os.IsNotExist(err) {
+		return
+	}
+
+	// If the new config directory already exists, do not move
+	if _, err := os.Stat(destDir); err == nil {
+		return
+	}
+
+	// Time to move
+	err := Copy(srcDir, destDir)
+	if err != nil {
+		panic(err)
+	} else {
+		logger.Log(fmt.Sprintf("Copied old config from %s to %s", srcDir, destDir))
+	}
+
+	// Delete the old directory if the new one exists
+	if _, err := os.Stat(destDir); err == nil {
+		err := os.RemoveAll(srcDir)
+		if err != nil {
+			logger.Log(err.Error())
+		}
+	}
+}
+
+/* -------------------- Config Migration -------------------- */
+
+// ConfigDir returns the absolute path to the configuration directory
 func ConfigDir() (string, error) {
-	configDir, err := wtf.ExpandHomeDir("~/.wtf/")
+	configDir, err := wtf.ExpandHomeDir(CONFIG_DIR_V2)
 	if err != nil {
 		return "", err
 	}
@@ -18,7 +60,7 @@ func ConfigDir() (string, error) {
 	return configDir, nil
 }
 
-// CreateConfigDir creates the .wtf directory in the user's home dir
+// CreateConfigDir creates the wtf/ directory in the user's home dir
 func CreateConfigDir() {
 	configDir, _ := ConfigDir()
 

cfg/copy.go

@@ -0,0 +1,75 @@
+// Copied verbatim from:
+//
+//   https://github.com/otiai10/copy/blob/master/copy.go
+
+package cfg
+
+import (
+	"io"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+)
+
+// Copy copies src to dest, doesn't matter if src is a directory or a file
+func Copy(src, dest string) error {
+	info, err := os.Stat(src)
+	if err != nil {
+		return err
+	}
+	return copy(src, dest, info)
+}
+
+// "info" must be given here, NOT nil.
+func copy(src, dest string, info os.FileInfo) error {
+	if info.IsDir() {
+		return dcopy(src, dest, info)
+	}
+	return fcopy(src, dest, info)
+}
+
+func fcopy(src, dest string, info os.FileInfo) error {
+
+	f, err := os.Create(dest)
+	if err != nil {
+		return err
+	}
+	defer f.Close()
+
+	if err = os.Chmod(f.Name(), info.Mode()); err != nil {
+		return err
+	}
+
+	s, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer s.Close()
+
+	_, err = io.Copy(f, s)
+	return err
+}
+
+func dcopy(src, dest string, info os.FileInfo) error {
+
+	if err := os.MkdirAll(dest, info.Mode()); err != nil {
+		return err
+	}
+
+	infos, err := ioutil.ReadDir(src)
+	if err != nil {
+		return err
+	}
+
+	for _, info := range infos {
+		if err := copy(
+			filepath.Join(src, info.Name()),
+			filepath.Join(dest, info.Name()),
+			info,
+		); err != nil {
+			return err
+		}
+	}
+
+	return nil
+}

flags/flags.go

@@ -68,6 +68,6 @@ func (flags *Flags) Parse() {
 			os.Exit(1)
 		}
 
-		flags.Config = filepath.Join(homeDir, ".wtf", "config.yml")
+		flags.Config = filepath.Join(homeDir, ".config", "wtf", "config.yml")
 	}
 }

logger/log.go

@@ -89,7 +89,7 @@ func logFilePath() string {
 		return ""
 	}
 
-	return filepath.Join(dir, ".wtf", "log.txt")
+	return filepath.Join(dir, ".config", "wtf", "log.txt")
 }
 
 func (widget *Widget) tailFile() []string {

wtf.go

@@ -243,6 +243,7 @@ func main() {
 	flags.Parse()
 	flags.Display(version)
 
+	cfg.MigrateOldConfig()
 	cfg.CreateConfigDir()
 	cfg.CreateConfigFile()
 	loadConfigFile(flags.ConfigFilePath())