+++ /dev/null
--module(life_time).
--behaviour(gen_server).
-
-
-%% API
--export([start_link/3
- ,report_state/2
- ]).
-
-%% Callbacks
--export([init/1
- ,handle_call/3
- ,handle_cast/2
- ,handle_info/2
- ,terminate/2
- ,code_change/3
- ]).
-
-
--define(INTERVAL, 100). % In milliseconds
-
--define(CHAR_DEAD, 32). % Space
--define(CHAR_ALIVE, 111). % o
--define(CHAR_BAR, 45). % -
-
-
--record(state, {x :: integer()
- ,y :: integer()
- ,cells :: list(atom())
- ,num_cells :: integer()
- ,state_pairs :: list(tuple(integer(), integer())) | []
- ,replies_pending :: integer()
- ,gen_id :: integer()
- }).
-
-
-%% ============================================================================
-%% API
-%% ============================================================================
-
-start_link(X, Y, Cells) ->
- ServerName = {local, ?MODULE},
- Args = [X, Y, Cells],
- Opts = [],
- gen_server:start_link(ServerName, ?MODULE, Args, Opts).
-
-
-report_state(CellID, CellState) ->
- gen_server:cast(?MODULE, {report_state, {CellID, CellState}}).
-
-
-%% ============================================================================
-%% Callbacks
-%% ============================================================================
-
-init([X, Y, Cells]) ->
- State = #state{x = X
- ,y = Y
- ,cells = Cells
- ,num_cells = length(Cells)
- ,state_pairs = []
- ,replies_pending = 0
- ,gen_id = 0
- },
- schedule_next_gen(),
- {ok, State}.
-
-
-terminate(_Reason, State) ->
- {ok, State}.
-
-
-code_change(_Old, State, _Other) ->
- {ok, State}.
-
-
-handle_call(_Msg, _From, State) ->
- {reply, ok, State}.
-
-
-handle_cast(next_gen,
- #state{cells=Cells
- ,num_cells=NumCells
- ,state_pairs=[]
- ,gen_id=GenID
- }=State) ->
-
- NewGenID = GenID + 1,
- ok = cast_all(Cells, {next_gen, NewGenID}),
- {noreply, State#state{replies_pending=NumCells, gen_id=NewGenID}};
-
-handle_cast({report_state, {ID, CellState}},
- #state{x=X
- ,y=Y
- ,state_pairs=StatePairs
- ,replies_pending=RepliesPending
- ,gen_id=GenID
- ,num_cells=NumCells
- }=State) ->
-
- NewStatePairs = [{ID, CellState} | StatePairs],
- NewRepliesPending = RepliesPending - 1,
- NewState = State#state{replies_pending=NewRepliesPending},
-
- case NewRepliesPending of
- 0 ->
- SortedStatePairs = lists:sort(
- fun({A, _}, {B, _}) -> A < B end,
- NewStatePairs
- ),
- StateChars = [state_to_char(S) || {_, S} <- SortedStatePairs],
-
- ok = io:format(
- "X: ~b Y: ~b CELLS: ~b GENERATION: ~b~n",
- [X, Y, NumCells, GenID]
- ),
- ok = do_print_bar(X),
-
- ok = do_print_state_chars(X, StateChars),
-
- ok = timer:sleep(?INTERVAL),
- schedule_next_gen(),
- {noreply, NewState#state{state_pairs=[]}};
-
- _N ->
- {noreply, NewState#state{state_pairs=NewStatePairs}}
- end;
-
-handle_cast(_Msg, State) ->
- {noreply, State}.
-
-
-handle_info(_Msg, State) ->
- {noreply, State}.
-
-
-%% ============================================================================
-%% Internal
-%% ============================================================================
-
-schedule_next_gen() ->
- gen_server:cast(?MODULE, next_gen).
-
-
-cast_all([], _) -> ok;
-cast_all([Server | Servers], Msg) ->
- ok = gen_server:cast(Server, Msg),
- cast_all(Servers, Msg).
-
-
-state_to_char(0) -> ?CHAR_DEAD;
-state_to_char(1) -> ?CHAR_ALIVE.
-
-
-do_print_state_chars(_, []) -> ok;
-do_print_state_chars(X, Chars) ->
- {XChars, RestChars} = lists:split(X, Chars),
- ok = io:format([XChars, $\n]),
- do_print_state_chars(X, RestChars).
-
-
-do_print_bar(X) ->
- io:format("~s~n", [[?CHAR_BAR || _ <- lists:seq(1, X - 1)]]).