% otherplaces.erl

-module(otherplaces).
-author('Alan G. Labouseur').
-define(else, true).  % -- This is to make the if statements (somewhat) readable.

%--------
% Public
%--------
-export([startP1/0, startP2/0, p1/0, p2/0, test/2]).

startP1() ->
   io:fwrite("~nstartP1() [pid ~w] has started on node ~w.~n~n", [self(), node()]),

   P1pid = spawn(otherplaces, p1, []),
   % We want to publish this process in Erlang's Process Dictionary.
   % Before we do that, we need to un-register it if it's already been registered.
   SomePlace = whereis(place1),
   if (SomePlace /= undefined) ->  % "not undefined" = "is defined"  (This is horrible, I know.)
      unregister(place1);
   ?else ->
      % The proccess was NOT already published/registered, so we don't really want to do anything here.
      true    % This is dumb, but I couldn't think of a better "no-op".
   end,

   % Publish this process in Erlang's Process Dictionary.
   register(place1, P1pid).


startP2() ->
   io:fwrite("~nstartP2() [pid ~w] has started on node ~w.~n~n", [self(), node()]),

   P2pid = spawn(otherplaces, p2, []),
   % We want to publish this process in Erlang's  Process Dictionary.
   % Before we do that, we need to un-register it if it's already been registered.
   SomePlace = whereis(place2),
   if (SomePlace /= undefined) ->  % "not undefined" = "is defined"  (This is horrible, I know.)
      unregister(place2);
   ?else ->
      % The proccess was NOT already published/registered, so we don't really want to do anything here.
      true    % This is dumb, but I couldn't think of a better "no-op".
   end,

   % Publish this process in Erlang's Process Dictionary.
   register(place2, P2pid).


% This is spawned from startP1().
p1() ->
   receive
      {From, Request} ->
         io:fwrite("p1() [pid ~w] received request [~w] from pid ~w.~n", [self(), Request, From]),
         Response = io_lib:format("This text is p1() [pid ~w's] on node [~w]'s response to pid ~w.~n", [self(), node(), From]),
         From ! Response,
         p1()
   end.


% This is spawned from startP2().
p2() ->
   receive
      {From, Request} ->
         io:fwrite("p2() [pid ~w] received request [~w] from pid ~w.~n", [self(), Request, From]),
         Response = io_lib:format("This text is p2() [pid ~w's] on node [~w]'s response to pid ~w.~n", [self(), node(), From]),
         From ! Response,
         p2()
   end.


test(Place, Node) ->
   io:fwrite("Testing ~w on node ~w.~n", [Place, Node]),
   {Place, Node} ! {self(), remoteRequest},
   receive
      Response -> io:fwrite("~s~n", [Response])  % Wait for ANY response.
   end.