with Ada.Text_IO;
with CSV;


package body Bundles is


    procedure Add_To_Map
           (BMap : in out Bundle_Maps.Map;
            Item : in     Given_Prefs.Preference_Array)
    is
        procedure Update_Bundle
               (B : in out Bundle) is
        begin
            Add (B, Item);
        end Update_Bundle;

        procedure Update_Vector
               (C : Candidates.CandidateID;
                V : Bundle_Vectors.Vector) is
        begin
            V.Update_Element (V.First_Index, Update_Bundle'Access);
        end Update_Vector;

        Place : Candidates.CandidateID := Item (Given_Prefs.Preference_Range'First);
        Current_Cursor : Bundle_Maps.Cursor := Result.Find (Place);
    begin
        if Current_Cursor /= Bundle_Maps.No_Element then
            BMap.Update_Element (Current_Cursor, Update_Vector'Access);
        else
            declare
                New_Bundle : Bundle := Empty_Bundle;
            begin
                Add (New_Bundle, Item);
                BMap.Insert (Place, Bundle_Vectors.Empty_Vector & New_Bundle);
            end;
        end if;
    end Add_To_Map;




    procedure Read_Bundles
           (Filename : in     String;
            Result   :    out Bundle_Maps.Map)
    is
        package My_CSV is new CSV;
        use Ada.Text_IO;

        Input_File : File_Type;
        Current_Record : My_CSV.CSV_Record;
        Current_Prefs : Given_Prefs.Preference_Array;
    begin
        Open (Input_File, In_File, Filename);

        Result := Bundle_Maps.Empty_Map;
        while not End_Of_File (Input_File) loop
            Current_Record := My_CSV.Parse_Line (Get_Line (Input_File));
            if Current_Record.Length > 0 then
                Current_Prefs := Given_Prefs.Parse_Preferences (Current_Record.Last_Element);
                if Current_Prefs (Given_Prefs.Preference_Range'First) /= Candidates.No_Candidate then
                    Add_To_Map (Result, Current_Prefs);
                end if;
            end if;
        end loop;

        Close (Input_File);
    end Read_Bundles;




    procedure Add
           (This : in out Bundle;
            Item : in     Given_Prefs.Preference_Array) is
    begin
        for P of This.Papers loop
            if P.Prefs = Item then
                P.How_Many := P.How_Many + 1;
                return;
            end if;
        end if;
        This.Papers.Append ( (How_Many => 1, Prefs => Item) );
    end Add;




    procedure Transfer
           (This     : in out Bundle;
            From, To : in     Candidates.CandidateID;
            Excluded : in     Candidates.CandidateID_Vector;
            Value    : in     Rationals.Fraction;
            Result   :    out Bundle)
    is
        Position : Positive;
    begin
        Result := Empty_Bundle;
        Result.Worth := This.Worth * Value;
        for P of This.Papers loop
            Position := Given_Prefs.Preference_Range'First;

            while Position <= Given_Prefs.Preference_Range'Last and then
                  P.Prefs (Position) /= From
            loop
                Position := Position + 1;
            end loop;
            Position := Position + 1;

            while Position <= Given_Prefs.Preference_Range'Last and then
                  Excluded.Contains (P.Prefs (Position))
            loop
                Position := Position + 1;
            end loop;

            if Position <= Given_Prefs.Preference_Range'Last and then
               P.Prefs (Position) = To
            then
                Result.Papers.Append (P);
            end if;
        end loop;
    end Transfer;




    function Count_Votes
           (This : in Bundle)
        return Natural is
    begin
        return Rationals.Floor (Count_Papers (This) * This.Worth);
    end Count_Votes;




    function Count_Papers
           (This : in Bundle)
        return Natural
    is
        Result : Natural := 0;
    begin
        for P of This.Papers loop
            Result := Result + P.How_Many;
        end loop;
        return Result;
    end Count_Papers;


end Bundles;