-module(sherl_db_SUITE).

-compile(export_all).

-include("../include/url.hrl").
-include_lib("ct.hrl").

%%--------------------------------------------------------------------
%% Function: suite() -> DefaultData
%% DefaultData: [tuple()]  
%% Description: Require variables and set default values for the suite
%%--------------------------------------------------------------------
suite() -> [{timetrap,{seconds,10}}].

%%--------------------------------------------------------------------
%% Function: init_per_suite(Config) -> Config
%% Config: [tuple()]
%%   A list of key/value pairs, holding the test case configuration.
%% Description: Initiation before the whole suite
%%
%% Note: This function is free to add any key/value pairs to the Config
%% variable, but should NOT alter/remove any existing entries.
%%--------------------------------------------------------------------
init_per_suite(Config) ->
    sherl_db:start([]),
    Config.

%%--------------------------------------------------------------------
%% Function: end_per_suite(Config) -> _
%% Config: [tuple()]
%%   A list of key/value pairs, holding the test case configuration.
%% Description: Cleanup after the whole suite
%%--------------------------------------------------------------------
end_per_suite(_Config) ->
    sherl_db:stop(),
    ok.

%%--------------------------------------------------------------------
%% Function: all() -> TestCases
%% TestCases: [Case] 
%% Case: atom()
%%   Name of a test case.
%% Description: Returns a list of all test cases in this test suite
%%--------------------------------------------------------------------      
all() -> 
    [unknown_url_is_undefined, roundtrip1, roundtrip2, concurrent_creating].

%%-------------------------------------------------------------------------
%% Test cases starts here.
%%-------------------------------------------------------------------------

unknown_url_is_undefined(_Config) ->
    undefined = sherl_db:get_url("no-such-url-in-db"),
    ok.

roundtrip1(_Config) ->
    Url1 = "url1",
    Ans1 = sherl_db:get_code(Url1),
    Url1 = Ans1#url.url,
    1 = Ans1#url.code,
    Ans1 = sherl_db:get_url(Ans1#url.code),

    %% same URL yields same record
    Ans1 = sherl_db:get_code(Url1),
    ok.

roundtrip2(_Config) ->
    Url2 = "url2",
    Ans2 = sherl_db:get_code(Url2),
    Url2 = Ans2#url.url,
    2 = Ans2#url.code,
    Ans2 = sherl_db:get_url(Ans2#url.code),
    ok.

concurrent_creating(_Config) ->
    NumClients = 50,
    Seq = lists:map(fun erlang:integer_to_list/1, lists:seq(1, 10)),
    Parent = self(),
    F = fun() ->
                Codes = lists:map(fun(N) ->
                                          sherl_db:get_code("http://" ++ N)
                                  end,
                                  Seq),
                Parent ! {self(), Codes}
        end,
    Pids = lists:map(fun(_X) -> spawn(F) end, lists:seq(1, NumClients)),
    %% Results = gather(Pids),
    Results = [ simple_gather(Pid) || Pid <- Pids ],
    io:format("PIDS: ~p~n", [Pids]),
    io:format("Results ~p~n", [Results]),
    Codes = [ X#url.code || X <- hd(Results) ],
    io:format("Codes ~p~n", [Codes]),
    ExpectedCodes = lists:seq(3, 12),
    lists:foreach(fun(L) ->
                          ExpectedCodes = [X#url.code || X <- L]
                  end,
                  Results),
    ok.

simple_gather(Pid) ->
    receive
        {Pid, Val} ->
            Val
    end.

gather([Pid|T]) ->
    receive
        {Pid, Val} ->
            [Val|gather(T)]
    end;
gather([]) ->
    [].