-- S.MG, 2018
 -- prototype implementation of S.MG communication protocol

with GNAT.Sockets; use GNAT.Sockets;
with Ada.Text_IO; use Ada.Text_IO;
with Ada.Streams; use Ada.Streams;
with Interfaces; use Interfaces;

with SMG_comms_types; use SMG_comms_types;

procedure test_comms is
  Port_No : constant := 2222;

  task type Client is
    entry Send;
  end Client;

  task type Server is
    entry Listen;
    entry Ready;
  end Server;

  task body Client is
    Sock: Socket_Type;
    Address: Sock_Addr_Type;
    Data: Ada.Streams.Stream_Element_Array(1..10) := (others => 42);
    Last: Ada.Streams.Stream_Element_Offset;
    N   : Integer_8 := -36;
  begin
    accept Send; -- task WILL block here until asked to send
    Address.Port := Port_No;
    Address.Addr := Inet_Addr("127.0.0.1");
    Create_Socket(Sock, Family_Inet, Socket_Datagram);

    ToNetworkFormat( N, Data(1..1));

    Send_Socket(Sock, Data, Last, Address);
    Put_Line("Client sent data " & "last: " & Last'Img);
  end Client;

  task body Server is
    Sock: Socket_Type;
    Address, From: Sock_Addr_Type;
    Data: Ada.Streams.Stream_Element_Array(1..512);
    Last: Ada.Streams.Stream_Element_Offset;
    N : Integer_8;
  begin
    accept Listen; -- wait to be started!
    Put_Line("Server started!");
    -- create UDP socket
    Create_Socket( Sock, Family_Inet, Socket_Datagram );

    -- set options on UDP socket
    Set_Socket_Option( Sock, Socket_Level, (Reuse_Address, True));
    Set_Socket_Option( Sock, Socket_Level, (Receive_Timeout, Timeout => 10.0));

    -- set address and bind
    Address.Addr := Any_Inet_Addr;
    Address.Port := Port_No;
    Bind_Socket( Sock, Address );

    accept Ready; -- server IS ready, when here
    -- receive on socket
    begin
      Receive_Socket( Sock, Data, Last, From );
      Put_Line("last: " & Last'Img);
      Put_Line("from: " & Image(From.Addr));
      Put_Line("data is:");
      for I in Data'First .. Last loop
        FromNetworkFormat(Data(I..I), N);
        Put_Line(N'Image);
      end loop;
    exception
      when Socket_Error =>
      Put_Line("Socket error! (timeout?)");
    end;  -- end of receive

  end Server;

  S: Server;
  C: Client;
begin
  S.Listen;
  S.Ready; -- WAIT for server to be ready!
  C.Send;  -- client is started only after server!
end test_comms;