%% The MIT License

%% Copyright (c) 2010 Alisdair Sullivan <alisdairsullivan@yahoo.ca>

%% Permission is hereby granted, free of charge, to any person obtaining a copy
%% of this software and associated documentation files (the "Software"), to deal
%% in the Software without restriction, including without limitation the rights
%% to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
%% copies of the Software, and to permit persons to whom the Software is
%% furnished to do so, subject to the following conditions:

%% The above copyright notice and this permission notice shall be included in
%% all copies or substantial portions of the Software.

%% THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
%% IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
%% FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
%% AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
%% LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
%% OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
%% THE SOFTWARE.


-module(jsx_verify).

-export([is_json/2, is_term/2]).
-export([init/1, handle_event/2]).


-record(opts, {
    repeated_keys = true
}).

-type opts() :: [].


-spec is_json(Source::binary(), Opts::opts()) -> true | false.

is_json(Source, Opts) when is_list(Opts) ->
    try (jsx:decoder(?MODULE, Opts, jsx_utils:extract_opts(Opts)))(Source)
    catch error:badarg -> false
    end.


-spec is_term(Source::any(), Opts::opts()) -> true | false.

is_term(Source, Opts) when is_list(Opts) ->
    try (jsx:encoder(?MODULE, Opts, jsx_utils:extract_opts(Opts)))(Source)
    catch error:badarg -> false
    end.


parse_opts(Opts) -> parse_opts(Opts, #opts{}).

parse_opts([{repeated_keys, Val}|Rest], Opts) when Val == true; Val == false ->
    parse_opts(Rest, Opts#opts{repeated_keys = Val});
parse_opts([repeated_keys|Rest], Opts) ->
    parse_opts(Rest, Opts#opts{repeated_keys = true});
parse_opts([{K, _}|Rest] = Options, Opts) ->
    case lists:member(K, jsx_utils:valid_flags()) of
        true -> parse_opts(Rest, Opts)
        ; false -> erlang:error(badarg, [Options, Opts])
    end;
parse_opts([K|Rest] = Options, Opts) ->
    case lists:member(K, jsx_utils:valid_flags()) of
        true -> parse_opts(Rest, Opts)
        ; false -> erlang:error(badarg, [Options, Opts])
    end;
parse_opts([], Opts) ->
    Opts.



init(Opts) -> {parse_opts(Opts), []}.



handle_event(end_json, _) -> true;

handle_event(_, {Opts, _} = State) when Opts#opts.repeated_keys == true -> State;

handle_event(start_object, {Opts, Keys}) -> {Opts, [dict:new()] ++ Keys};
handle_event(end_object, {Opts, [_|Keys]}) -> {Opts, Keys};

handle_event({key, Key}, {Opts, [CurrentKeys|Keys]}) ->
    case dict:is_key(Key, CurrentKeys) of
        true -> erlang:error(badarg)
        ; false -> {Opts, [dict:store(Key, blah, CurrentKeys)|Keys]}
    end;

handle_event(_, State) -> State.



%% eunit tests
-ifdef(TEST).
-include_lib("eunit/include/eunit.hrl").


opts_test_() ->
    [
        {"empty opts", ?_assertEqual(#opts{}, parse_opts([]))},
        {"bare repeated keys", ?_assertEqual(#opts{}, parse_opts([repeated_keys]))},
        {"repeated keys true", ?_assertEqual(
            #opts{},
            parse_opts([{repeated_keys, true}])
        )},
        {"repeated keys false", ?_assertEqual(
            #opts{repeated_keys=false},
            parse_opts([{repeated_keys, false}])
        )},
        {"invalid opt flag", ?_assertError(badarg, parse_opts([error]))},
        {"invalid opt tuple", ?_assertError(badarg, parse_opts([{error, true}]))}
    ].


handle_event_test_() ->
    Data = jsx:empty_array()
        ++ jsx:deep_array()
        ++ jsx:really_deep_array()
        ++ jsx:empty_object()
        ++ jsx:literals()
        ++ jsx:naked_literals()
        ++ jsx:integers()
        ++ jsx:naked_integers()
        ++ jsx:floats()
        ++ jsx:naked_floats(),
    [
        {
            Title, ?_assertEqual(
                true,
                lists:foldl(fun handle_event/2, {#opts{}, []}, Events ++ [end_json])
            )
        } || {Title, _, _, Events} <- Data
    ].


-endif.