Configuration fields in game rules screen are editable

rust/sea_battle_backend/src/data/game_rules.rs

@@ -61,6 +61,10 @@ impl GameRules {
 
     /// Get the list of boats for this configuration
     pub fn boats_list(&self) -> Vec<usize> {
+        if self.boats_str.is_empty() {
+            return vec![];
+        }
+
         self.boats_str
             .split(',')
             .map(|s| s.parse::<usize>().unwrap_or_default())
@@ -78,7 +82,7 @@ impl GameRules {
     pub fn add_boat(&mut self, len: usize) {
         let mut list = self.boats_list();
         list.push(len);
-        self.set_boats_list(&list[0..list.len() - 1]);
+        self.set_boats_list(&list);
     }
 
     /// Check game rules errors
@@ -109,6 +113,11 @@ impl GameRules {
 
         errors
     }
+
+    /// Check out whether these game rules are valid or not
+    pub fn is_valid(&self) -> bool {
+        return self.get_errors().is_empty();
+    }
 }
 
 #[cfg(test)]