-module(websocket_app).

-behaviour(application).

%% Application callbacks

-export([start/, stop/]).

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

%% Application callbacks

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

start(_StartType, _StartArgs) ->

    %%启动存储pid的树据 可以采用 ets 表格处理 但是为了方便集群处理 我采用的mnesia

    ok = websocket_store:init(),

    %% 配置路由

    Dispatch = cowboy_router:compile([

                      {'_', [

                         {"/", cowboy_static, {priv_file, websocket, "index.html"}},

                         {"/websocket", websocket_hander, []},

                         {"/static/[...]", cowboy_static, {priv_dir,  websocket, "static"}}

                        ]}

                     ]),

    {ok, _} = cowboy:start_http(http, , [{port, }],

                [{env, [{dispatch, Dispatch}]}]),

    %%启动监督树

    websocket_sup:start_link().

stop(_State) ->

    ok.

-module(websocket_hander).

-behaviour(cowboy_websocket_handler).

%% ------------------------------------------------------------------

%% API Function Exports

%% ------------------------------------------------------------------

%% ------------------------------------------------------------------

%% gen_server Function Exports

%% ------------------------------------------------------------------

-export([init/]).

-export([websocket_init/]).

-export([websocket_handle/]).

-export([websocket_info/]).

-export([websocket_terminate/]).

%% ------------------------------------------------------------------

%% API Function Definitions

%% ------------------------------------------------------------------

%% ------------------------------------------------------------------

%% gen_server Function Definitions

%% ------------------------------------------------------------------

%%websocket 握手

init({tcp, http}, _Req, _Opts) ->

    %%插入数据

    websocket_store:dirty_insert(self(),web),

    {upgrade, protocol, cowboy_websocket}.

%%连接初始

websocket_init(_TransportName, Req, _Opts) ->

    %%连接一秒后 发送消息

    erlang:start_timer(, self(), <<"Hello!">>),

    {ok, Req, undefined_state}.

%%处理客户端发送投递的消息

websocket_handle({text, Msg}, Req, State) ->

    %% 把消息投递到其余的进程 这里可以 投递到 tcp socket  也可以投递的 websocket 这样就可以实现 服务支持多协议处理

     lists:foreach(fun([Pid,SocketType]) ->

              case SocketType of

                  tcp -> ok;

                  web ->

                  case Pid == self() of

                      true -> ok;

                      false -> Pid!{chat,Msg}

                  end

              end

          end,websocket_store:dirty_lookall()),

    {reply, {text, << "That's what she said! ", Msg/binary >>}, Req, State};

websocket_handle(_Data, Req, State) ->

    {ok, Req, State}.

%% 处理erlang 发送的消息 这里是接收  行发送的数据

websocket_info({chat,Msg},_Req,State)->

    {reply,{text,Msg},_Req,State};

%% 处理     erlang:start_timer(, self(), <<"Hello!">>) 发送的消息

websocket_info({timeout, _Ref, Msg}, Req, State) ->

    {reply, {text, Msg}, Req, State};

websocket_info(_Info, Req, State) ->

    {ok, Req, State}.

%%断开socket

websocket_terminate(_Reason, _Req, _State) ->

    websocket_store:dirty_delete(self()),

    ok.

%% ------------------------------------------------------------------

%% Internal Function Definitions

%% ------------------------------------------------------------------

%%%-------------------------------------------------------------------

%%% @author thinkpad <>

%%% @copyright (C) , thinkpad

%%% @doc

%%%

%%% @end

%%% Created :  Jun  by thinkpad <>

%%%-------------------------------------------------------------------

-module(websocket_store).

-include_lib("stdlib/include/qlc.hrl" ).

%% API

-export([dirty_insert/,dirty_lookall/,dirty_lookall_record/,dirty_delete/]).

-export([init/,insert/,delete/,lookup/,lookall/]).

-record(socket_to_pid, {pid,socket_type}).

-define(WAIT_FOR_TABLES, ).

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

%%% API

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

init()->

    dynamic_db_init().

%--------------------------------------------------------------------

%% @doc Insert a key and pid.

%% @spec insert(Key, Pid) -> void()

%% @end

%%--------------------------------------------------------------------

insert(Pid,SocketType) when is_pid(Pid) ->

    Fun = fun() -> mnesia:write(#socket_to_pid{pid = Pid, socket_type = SocketType}) end,

    {atomic, _} = mnesia:transaction(Fun).

%--------------------------------------------------------------------

%% @doc  dirty insert pid and socket

%% @spec  dirty_insert(Pid socket)

%% @end

%%--------------------------------------------------------------------

dirty_insert(Pid,SocketType) when is_pid(Pid) ->

    mnesia:dirty_write(#socket_to_pid{pid = Pid, socket_type = SocketType}).

%--------------------------------------------------------------------

%% @doc dirty_read data

%% @spec dirty_lookall()

%% @end

%%--------------------------------------------------------------------

dirty_lookall()->

    mnesia:dirty_select(socket_to_pid,[{#socket_to_pid{pid='$1',socket_type = '$2'},[],['$$']}]).

dirty_delete(Pid)->

    mnesia:dirty_delete(socket_to_pid,Pid).

%--------------------------------------------------------------------

%% @doc look all record info

%% @spec

%% @end

%%--------------------------------------------------------------------

dirty_lookall_record()->

     mnesia:dirty_select(socket_to_pid,[{#socket_to_pid{pid='$1',socket_type = '$2'},[],['$_']}]).

%%--------------------------------------------------------------------

%% @doc Find a pid given a key.

%% @spec lookup(Key) -> {ok, Pid} | {error, not_found}

%% @end

%%--------------------------------------------------------------------

lookup(Pid) ->

       do(qlc:q([{X#socket_to_pid.pid,X#socket_to_pid.socket_type} || X <- mnesia:table(socket_to_pid),X#socket_to_pid.pid==Pid])).

%%--------------------------------------------------------------------

%% @doc Find all list

%% @spec lookall() -> {List} | {error, not_found}

%% @end

%%--------------------------------------------------------------------

lookall() ->

         do(qlc:q([[X#socket_to_pid.pid,X#socket_to_pid.socket_type] || X <- mnesia:table(socket_to_pid)])).

%%--------------------------------------------------------------------

%% @doc Delete an element by pid from the registrar.

%% @spec delete(Pid) -> void()

%% @end

%%--------------------------------------------------------------------

delete(Pid) ->

    try

        [#socket_to_pid{} = Record] = mnesia:dirty_read(socket_to_pid, Pid, #socket_to_pid.pid),

        mnesia:dirty_delete_object(Record)

    catch

        _C:_E -> ok

    end.

%%--------------------------------------------------------------------

%% @doc

%% @spec

%% @end

%%--------------------------------------------------------------------

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

%%% Internal functions

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

dynamic_db_init() ->

    delete_schema(),

    {atomic, ok} = mnesia:create_table(socket_to_pid, [{attributes, record_info(fields, socket_to_pid)}]),

    ok.

%% deletes a local schema.

delete_schema() ->

    mnesia:stop(),

    mnesia:delete_schema([node()]),

    mnesia:start().

do(Query) ->

    F = fun() -> qlc:e(Query) end,

    {atomic, Value} = mnesia:transaction(F),

    Value.