feat: improve config file handling

- add default config file
- read passed config file or use default if none provided
- ensure cli parameters always supersede config file settings
- add function to check if a file exists

🤖

internal/helper/files.go

@@ -0,0 +1,42 @@
+package helper
+
+import (
+	"github.com/charmbracelet/log"
+	"gopkg.in/yaml.v3"
+	"os"
+	"path/filepath"
+	"strings"
+
+	ChronoTomato "git.smsvc.net/pomodoro/ChronoTomato/pkg/models"
+)
+
+func expandUnixPath(filename string) string {
+	if strings.HasPrefix(filename, "~/") {
+		dirname, _ := os.UserHomeDir()
+		filename = filepath.Join(dirname, filename[2:])
+	}
+
+	return filename
+}
+
+func FileExists(filename string) bool {
+	_, err := os.Stat(expandUnixPath(filename))
+
+	return !os.IsNotExist(err)
+}
+
+func ParseConfig(filename string) ChronoTomato.Config {
+	var config ChronoTomato.Config
+
+	yamlFile, err := os.ReadFile(expandUnixPath(filename))
+	if err != nil {
+		log.Fatal("Error opening config file!", "reason", err)
+	}
+
+	err = yaml.Unmarshal(yamlFile, &config)
+	if err != nil {
+		log.Fatalf("Unmarshal: %v", err)
+	}
+
+	return config
+}