fix battle

contracts/src/models/combat.cairo

@@ -167,6 +167,23 @@ impl TroopsImpl of TroopsTrait {
         return resource_precision_u64;
     }
 
+    fn assert_minimum_for_battle(self: Troops) {
+        assert!(
+            self.knight_count >= (100 * RESOURCE_PRECISION).try_into().unwrap(),
+            "you need to at least have 100 knights to merge or battle"
+        );
+
+        assert!(
+            self.paladin_count >= (100 * RESOURCE_PRECISION).try_into().unwrap(),
+            "you need to at least have 100 paladins to merge or battle"
+        );
+
+        assert!(
+            self.crossbowman_count >= (100 * RESOURCE_PRECISION).try_into().unwrap(),
+            "you need to at least have 100 crossbowmen to merge or battle"
+        );
+    }
+
     fn assert_normalized(self: Troops) {
         assert!(
             self.knight_count % Self::normalization_factor() == 0,

contracts/src/systems/combat/contracts/battle_systems.cairo

@@ -364,6 +364,7 @@ mod battle_systems {
 
             let mut attacking_army: Army = world.read_model(attacking_army_id);
             attacking_army.assert_not_in_battle();
+            attacking_army.troops.assert_minimum_for_battle();
 
             let attacking_army_entity_owner: EntityOwner = world.read_model(attacking_army_id);
             attacking_army_entity_owner.assert_caller_owner(world);
@@ -877,6 +878,7 @@ mod battle_pillage_systems {
             // ensure attacking army is not in a battle
             let mut attacking_army: Army = world.read_model(army_id);
             attacking_army.assert_not_in_battle();
+            attacking_army.troops.assert_minimum_for_battle();
 
             // ensure army is at structure position
             let army_position: Position = world.read_model(army_id);