add seed gen for code with 4 digit

app/models/menu_category.rb

@@ -39,6 +39,6 @@ class MenuCategory < ApplicationRecord
   private
 
   def generate_menu_category_code
-    self.code = SeedGenerator.generate_id(self.class.name, "C")
+    self.code = SeedGenerator.generate_code(self.class.name, "C")
   end
 end

app/models/menu_item.rb

@@ -73,7 +73,7 @@ class MenuItem < ApplicationRecord
   private
 
   def generate_menu_item_code
-    self.item_code = SeedGenerator.generate_id(self.class.name, "I")
+    self.item_code = SeedGenerator.generate_code(self.class.name, "I")
   end
 
 end

app/models/menu_item_instance.rb

@@ -14,6 +14,6 @@ class MenuItemInstance < ApplicationRecord
   private
 
   def generate_menu_item_instance_code
-    self.item_instance_code = SeedGenerator.generate_id(self.class.name, "II")
+    self.item_instance_code = SeedGenerator.generate_code(self.class.name, "II")
   end
 end

app/models/seed_generator.rb

@@ -1,5 +1,5 @@
 class SeedGenerator < ApplicationRecord
-
+  # Generate ID for Tables
   def self.generate_id(model, prefix)
     seed = SeedGenerator.find_by_model(model)
     new_receipt_no = 0
@@ -23,6 +23,7 @@ class SeedGenerator < ApplicationRecord
 
   end
 
+  # Generate Receipt No
   def self.new_receipt_no
     seed = SeedGenerator.find_by_model("sale")
     new_receipt_no = 0
@@ -41,4 +42,27 @@ class SeedGenerator < ApplicationRecord
 
     return seed.current
   end
+
+  # Generate for 4 digit Code
+  def self.generate_code(model, prefix)
+    seed = SeedGenerator.find_by_model(model)
+    new_code = 0
+
+    if (seed.nil?)
+      seed = SeedGenerator.new()
+      seed.model = model
+      new_code = seed.next
+      seed.save
+    else
+      current_no = seed.next
+      seed.next = seed.next + seed.increase_by
+      seed.current = current_no
+      seed.save
+    end
+
+    padding_len = 5 - prefix.length
+    next_code = prefix +"-"+ seed.current.to_s.to_s.rjust((4-prefix.length)+1,'0')
+    return next_code
+
+  end
 end