refactor: standardize URL validation and move it to config package

Author: revelaction

config/config.go

@@ -157,7 +157,7 @@ func Load(data []byte) (Config, error) {
 		data, err := decodeBase64URI(im.Value)
 		if err != nil {
 			// try external URL
-			errUrl := validateUrl(im.Value)
+			errUrl := ValidateUrl(im.Value)
 			if errUrl != nil {
 				return Config{}, fmt.Errorf("Image %d error: bad base64 format[%w], bad Url format [%w]", i, err, errUrl)
 			}
@@ -229,7 +229,7 @@ func decodeBase64URI(s string) ([]byte, error) {
 	return decodedData, nil
 }
 
-func validateUrl(urlStr string) error {
+func ValidateUrl(urlStr string) error {
 	u, err := url.Parse(urlStr)
 	if err != nil {
 		return fmt.Errorf("invalid URL format: %v", err)

ical/parse.go

@@ -165,11 +165,13 @@ func (p *Parser) buildNotification(event *ics.VEvent) notify.Notification {
 				n.ImageName = image.Name
 			}
 		} else {
-			// only external Url
-			// check https TODO
-			if seemsImageFile(imageUrlProp.Value) {
-				n.ImageUrl = imageUrlProp.Value
-				n.ImageName = imageUrlProp.Value
+			// TODO move validation from config
+			err := config.ValidateUrl(imageUrlProp.Value)
+			if err == nil {
+				if seemsImageFile(imageUrlProp.Value) {
+					n.ImageUrl = imageUrlProp.Value
+					n.ImageName = imageUrlProp.Value
+				}
 			}
 		}
 	}