alara

%% ============================================================================

%% ALARA - Distributed Entropy Network System

%% Complete Erlang Implementation based on Coq Formalization

%% ============================================================================


-module(alara).
-behaviour(gen_server).
-include_lib("alara/include/alara.hrl").

%% API

-export([

    start_link/1,

    create_network/0,

    create_network/1,

    get_network_state/1,

    get_nodes/1,

    generate_random_bools/1,

    generate_random_bools/2,

    generate_random_int/1

]).

%% gen_server callbacks

-export([init/1, handle_call/3, handle_cast/2, handle_info/2,

         terminate/2, code_change/3]).

%% ============================================================================

%% API FUNCTIONS

%% ============================================================================


%% Create a network with 3 nodes

create_network() ->
    gen_server:start_link(?MODULE, [3], []).

%% Create a network with N nodes

create_network(NumNodes) ->
    gen_server:start_link(?MODULE, [NumNodes], []).

start_link(NumNodes) ->
    gen_server:start_link(?MODULE, [NumNodes], []).

%% Get the current network state

get_network_state(NetworkPid) ->
    gen_server:call(NetworkPid, get_network_state).

%% Get all node PIDs in the network

get_nodes(NetworkPid) ->
    gen_server:call(NetworkPid, get_nodes).

%% Generate N random booleans distributed across all nodes in the supervisor

generate_random_bools(N) when is_integer(N), N > 0 ->
    alara_node_sup:generate_random_bools(N).

%% Generate N random booleans from a specific node

generate_random_bools(NodePid, N) when is_integer(N), N > 0 ->
    [alara_node:get_random(NodePid) || _ <- lists:seq(1, N)].

%% Generate a random integer using NBits distributed across all nodes in the supervisor

generate_random_int(NBits) when is_integer(NBits), NBits > 0 ->
    alara_node_sup:generate_random_int(NBits).

%% ============================================================================

%% GEN_SERVER CALLBACKS

%% ============================================================================


init([NumNodes]) when is_integer(NumNodes), NumNodes > 0 ->
    process_flag(trap_exit, true),
    %% Start the node supervisor - it automatically starts all nodes

    SupPid = case alara_node_sup:start_link(NumNodes) of
        {ok, Pid} -> Pid;
        {error, {already_started, Pid}} -> Pid
    end,

    %% Get the node PIDs that were just started

    NodePids = alara_node_sup:get_nodes(),

    State = #state{

        nodes = NodePids,

        node_supervisor = SupPid

    },
    {ok, State}.

handle_call(get_network_state, _From, State) ->
    {reply, {ok, State}, State};

handle_call(get_nodes, _From, State) ->
    {reply, {ok, State#state.nodes}, State};

handle_call(_Request, _From, State) ->
    {reply, {error, unknown_request}, State}.

handle_cast(_Msg, State) ->
    {noreply, State}.

handle_info({'EXIT', Pid, Reason}, State) ->
    io:format("Process ~p exited with reason: ~p~n", [Pid, Reason]),
    {noreply, State};

handle_info(_Info, State) ->
    {noreply, State}.

terminate(_Reason, _State) ->
    ok.

code_change(_OldVsn, State, _Extra) ->
    {ok, State}.