Partial IBAN parser added

lib/iban_ex/country/template.ex

@@ -9,7 +9,10 @@ defmodule IbanEx.Country.Template do
 
   @callback size() :: size()
   @callback rule() :: rule()
-  @callback incomplete_rule() :: rule()
+  @callback rules() :: []
+  @callback rules_map() :: %{}
+  @callback bban_fields() :: [atom()]
+  @callback bban_size() :: non_neg_integer()
   @callback to_string(Iban.t(), joiner()) :: String.t()
   @callback to_string(Iban.t()) :: String.t()
 
@@ -47,26 +50,50 @@ def size(), do: @size
       @spec rule() :: Regex.t()
       def rule(), do: @rule
 
-      @doc """
-      Return Regex without trailing “$” for parsing incomplete BBAN (part of IBAN string) (for partial suggestions)
-      """
       @impl IbanEx.Country.Template
-      @spec incomplete_rule() :: Regex.t()
-      def incomplete_rule() do
+      @spec bban_size() :: integer()
+      def bban_size() do
+        {_rules, bban_size} = calculate_rules()
+        bban_size
+      end
+
+      @impl IbanEx.Country.Template
+      @spec bban_fields() :: []
+      def bban_fields(), do: rules_map() |> Map.keys()
+
+      @impl IbanEx.Country.Template
+      @spec rules_map() :: %{}
+      def rules_map(), do: rules() |> Map.new()
+
+      @impl IbanEx.Country.Template
+      @spec rules() :: []
+      def rules() do
+        {rules, _bban_size} = calculate_rules()
+        rules
+      end
+
+      defp calculate_rules() do
+        scanner = ~r/\(\?\<([\w_]+)\>(([^{]+)\{(\d+)\})\)/i
+
         source =
           @rule
           |> Regex.source()
-          |> String.slice(0..-2//1)
-          |> String.replace("{", "{0,")
 
-        opts =
-          @rule
-          |> Regex.opts()
+        {list, bban_length} =
+          Regex.scan(scanner, source)
+          |> Enum.reduce({[], 0}, fn [_part, k, r, _syms, l], {list, position} = acc ->
+            key = String.to_atom(k)
+            {:ok, regex} = Regex.compile(r, "i")
+            length = String.to_integer(l)
+            left = position
+            right = left + length - 1
+            {[{key, %{regex: regex, range: left..right}} | list], right + 1}
+          end)
 
-        Regex.compile!(source, opts)
+        {Enum.reverse(list), bban_length}
       end
 
-      defoverridable to_string: 1, to_string: 2, size: 0, rule: 0, incomplete_rule: 0
+      defoverridable to_string: 1, to_string: 2, size: 0, rule: 0
     end
   end
 end