create .restic and config files if not existing, with default values

restic/config.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"github.com/rs/zerolog/log"
 	"os"
+	"path/filepath"
 	"time"
 )
 
@@ -29,23 +30,23 @@ func IsDev() bool {
 }
 
 func PasswordFile() string {
-	return configDir + "password.txt"
+	return filepath.Join(configDir, "password.txt")
 }
 
 func LogFile() string {
-	return configDir + "log.txt"
+	return filepath.Join(configDir, "log.txt")
 }
 
 func ExcludeFile() string {
-	return configDir + "excludes.txt"
+	return filepath.Join(configDir, "excludes.txt")
 }
 
 func ConfigFile() string {
-	return configDir + "config.json"
+	return filepath.Join(configDir, "config.json")
 }
 
 func (cnf *Config) MountDir() string {
-	return configDir + "mnt"
+	return filepath.Join(configDir, "mnt")
 }
 
 func (cnf *Config) CreateMountDirIfDoesntExist() error {
@@ -55,13 +56,25 @@ func (cnf *Config) CreateMountDirIfDoesntExist() error {
 	return nil
 }
 
+func defaultConfig() *Config {
+	return &Config{
+		BackupTimeInHours: DefaultBackupTimeInHours,
+		Backup:            home,
+		Repository:        os.TempDir(),
+	}
+}
+
 func ReadConfig() (*Config, error) {
 	confData, err := os.ReadFile(ConfigFile())
+	conf := &Config{}
+
 	if err != nil {
-		return nil, fmt.Errorf("No config.json found: %w", err)
+		log.Warn().Err(err).Msg("No config.json found, writing default")
+		conf = defaultConfig()
+		confData, _ := json.Marshal(conf)
+		os.WriteFile(ConfigFile(), confData, os.ModePerm)
 	}
 
-	conf := &Config{}
 	err = json.Unmarshal(confData, conf)
 	if err != nil {
 		return nil, fmt.Errorf("config.json malformed JSON: %w", err)
@@ -75,5 +88,12 @@ func ReadConfig() (*Config, error) {
 		conf.BackupTimeInHours = DefaultBackupTimeInHours
 	}
 
+	if _, err := os.Stat(ExcludeFile()); os.IsNotExist(err) {
+		os.WriteFile(ExcludeFile(), []byte(""), os.ModePerm)
+	}
+	if _, err := os.Stat(PasswordFile()); os.IsNotExist(err) {
+		os.WriteFile(PasswordFile(), []byte(""), os.ModePerm)
+	}
+
 	return conf, nil
 }