gnatcoll-db includes dborm.py, need to understand routines in python

Question

I was using gnatcoll-db, but the limitations made me to rewrite dborm.py in Ada. There are two routines in dborm.py (in python) that I don't understand, specifically compute_table_aliases and fields_count_array.

Any help will be welcome. Of course, the modifications can be shared between all of us.

Edited to complete information:

My project fork is here. I don't want to copy here the complete routines from dborm.py as I don't know exactly the license terms of ACS. dborm.py can be downloaded from https://github.com/AdaCore/gnatcoll-db/tree/master/gnatcoll_db2ada.

The routines that I want to translate to Ada are:

• compute_table_aliases, lines 2407 to 2448. Really I don't understand the algorithm.
• fields_count_array and fields_count, lines 2372 to 2397. For these routines I have a translation to Ada but when testing, the result is OK except in a few cases.

Here is my translation to Ada:

Max_Depth : constant := 3; type Counts_Array is array (0 .. Max_Depth) of Integer;

  function Fields_Count_Array (T         : Table_Description;
                               Follow_LJ : Boolean;
                               DepthMax  : Integer;
                               FKStop    : Field := No_Field)
                            return Counts_Array is
     FK_Stop : Boolean; -- to be reset before each call to fields_count_
     Depth   : Integer := 0;
     Temp    : Counts_Array;

     function Fields_Count (T         : Table_Description;
                            Depth     : Integer;
                            Follow_LJ : Boolean;
                            FKStop    : Field := No_Field) return Integer;
     function Fields_Count (T         : Table_Description;
                            Depth     : Integer;
                            Follow_LJ : Boolean;
                            FKStop    : Field := No_Field)
                         return Integer is
        Result : Integer;
        procedure Process_FK (FK : in out Field);
        procedure Process_FK (FK : in out Field) is
        begin
           if FK = FKStop then
              FK_Stop := True;
              return;
           end if;
           if FK_Stop then
              return;
           end if;
           if Follow_LJ or (not FK.Can_Be_Null) then
              Result := Result +
                Fields_Count (Pointed_Table (FK), Depth - 1, Follow_LJ);
           end if;
        end Process_FK;
     begin
        Result := Num_Fields (T);
        if Depth > 0 then
           For_Each_FK (T, Process_FK'Access);
        end if;
        return Result;
     end Fields_Count;

  begin
     while Depth <= DepthMax loop
        FK_Stop := False;
        Temp (Depth) := Fields_Count (T, Depth, Follow_LJ, FKStop);
        Depth := Depth + 1;
     end loop;
     return Temp;
  end Fields_Count_Array;

Note that all type definitions come from gnatcoll-sql.

I understand that this is difficult to follow, perphaps may be better if I send a report on the modifications and the complete new Ada package replacing dborm.py. How?