-module(ephp_lib_info).

-author('manuel@altenwald.com').

-behaviour(ephp_lib).

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

-include("ephp.hrl").

-export([init_func/0, init_config/0, init_const/0, phpinfo/3, phpversion/2,
         php_sapi_name/2, php_logo_guid/2, ini_get/3, ini_set/4, set_include_path/3,
         get_include_path/2, version_compare/5, extension_loaded/3, memory_get_usage/3,
         memory_get_peak_usage/3]).

-define(INFO_GENERAL, 2#0000001).
-define(INFO_CREDITS, 2#0000010).
-define(INFO_CONFIGURATION, 2#0000100).
-define(INFO_MODULES, 2#0001000).
-define(INFO_ENVIRONMENT, 2#0010000).
-define(INFO_VARIABLES, 2#0100000).
-define(INFO_LICENSE, 2#1000000).
-define(INFO_ALL, 2#1111111).

-spec init_func() -> ephp_lib:php_function_results().
init_func() ->
    [{phpinfo, [{args, {0, 1, undefined, [{integer, ?INFO_ALL}]}}]},
     php_sapi_name,
     php_logo_guid,
     phpversion,
     ini_get,
     ini_set,
     set_include_path,
     get_include_path,
     {version_compare, [{args, {2, 2, undefined, [string, string, {string, undefined}]}}]},
     {extension_loaded, [{args, {1, 1, undefined, [string]}}]},
     {memory_get_usage, [{args, {0, 1, undefined, [{boolean, false}]}}]},
     {memory_get_peak_usage, [{args, {0, 1, undefined, [{boolean, false}]}}]}].

-spec init_config() -> ephp_lib:php_config_results().
init_config() ->
    [].

-spec init_const() -> ephp_lib:php_const_results().
init_const() ->
    [{<<"PHP_VERSION">>, ?PHP_VERSION}, {<<"PHP_MAJOR_VERSION">>, <<?PHP_MAJOR_VERSION>>},
     {<<"PHP_MINOR_VERSION">>, <<?PHP_MINOR_VERSION>>},
     {<<"PHP_RELEASE_VERSION">>, <<?PHP_RELEASE_VERSION>>},
     {<<"PHP_VERSION_ID">>, ?PHP_VERSION_ID}, {<<"PHP_EXTRA_VERSION">>, ?PHP_EXTRA_VERSION},
     % Zend Thread Safety
     {<<"PHP_ZTS">>, 0},
     {<<"PHP_DEBUG">>, 0},
     % TODO: move to ephp_lib_file?
     {<<"PHP_MAXPATHLEN">>, 1024},
     {<<"PHP_OS">>, get_os()}, {<<"PHP_OS_FAMILY">>, get_os_family()},
     {<<"PHP_SAPI">>, ephp_config:get(sapi_type, <<"cli">>)}, {<<"PHP_EOL">>, get_os_eol()},
     % fake:
     {<<"PHP_SHLIB_SUFFIX">>, <<"so">>},
     % assert options:
     {<<"INI_USER">>, 1},
     {<<"INI_PERDIR">>, 2}, {<<"INI_SYSTEM">>, 4}, {<<"INI_ALL">>, 7},
     % phpinfo constants:
     {<<"INFO_GENERAL">>, ?INFO_GENERAL},
     {<<"INFO_CREDITS">>, ?INFO_CREDITS}, {<<"INFO_CONFIGURATION">>, ?INFO_CONFIGURATION},
     {<<"INFO_MODULES">>, ?INFO_MODULES}, {<<"INFO_ENVIRONMENT">>, ?INFO_ENVIRONMENT},
     {<<"INFO_VARIABLES">>, ?INFO_VARIABLES}, {<<"INFO_LICENSE">>, ?INFO_LICENSE},
     {<<"INFO_ALL">>, ?INFO_ALL}].

-spec phpinfo(ephp:context_id(), line(), var_value()) -> undefined.
phpinfo(Context, Line, {_, Flags}) ->
    case php_sapi_name(Context, Line) of
        <<"cli", _/binary>> ->
            process_phpinfo("text", Context, Flags);
        _ ->
            process_phpinfo("html", Context, Flags)
    end.

-spec phpversion(ephp:context_id(), line()) -> binary().
phpversion(_Context, _Line) ->
    ?PHP_VERSION.

-spec php_sapi_name(ephp:context_id(), line()) -> binary().
php_sapi_name(_Context, _Line) ->
    ephp_config:get(sapi_type, <<"cli">>).

-spec php_logo_guid(ephp:context_id(), line()) -> binary().
php_logo_guid(_Context, _Line) ->
    Content = get_file("bragful_logo.png"),
    Base64Content = base64:encode(Content),
    <<"data:image/png;base64,", Base64Content/binary>>.

-spec ini_get(ephp:context_id(), line(), var_value()) -> mixed().
ini_get(_Context, _Line, {_, Key}) ->
    ephp_config:get(Key).

-spec ini_set(ephp:context_id(), line(), var_value(), var_value()) -> binary().
ini_set(_Context, _Line, {_, Key}, {_, Value}) ->
    PrevVal = ephp_config:get(Key),
    ephp_config:set(Key, Value),
    PrevVal.

-spec set_include_path(ephp:context_id(), line(), var_value()) -> binary().
set_include_path(_Context, _Line, {_, NewPath}) ->
    ephp_config:set(<<"include_path">>, NewPath),
    NewPath.

-spec get_include_path(ephp:context_id(), line()) -> binary().
get_include_path(_Context, _Line) ->
    ephp_config:get(<<"include_path">>).

-spec version_compare(ephp:context_id(),
                      line(),
                      Vsn1 :: var_value(),
                      Vsn2 :: var_value(),
                      Op :: var_value()) ->
                         boolean() | integer().
version_compare(_Context, _Line, {_, Vsn1}, {_, Vsn2}, {_, undefined}) ->
    ephp_string:vsn_cmp(Vsn1, Vsn2);
version_compare(_Context, _Line, {_, Vsn1}, {_, Vsn2}, {_, Op}) ->
    case {Op, ephp_string:vsn_cmp(Vsn1, Vsn2)} of
        {<<"<">>, -1} ->
            true;
        {<<"lt">>, -1} ->
            true;
        {<<"<=">>, I} when I =< 0 ->
            true;
        {<<"le">>, I} when I =< 0 ->
            true;
        {<<">">>, 1} ->
            true;
        {<<"gt">>, 1} ->
            true;
        {<<">=">>, I} when I >= 0 ->
            true;
        {<<"ge">>, I} when I >= 0 ->
            true;
        {<<"==">>, 0} ->
            true;
        {<<"=">>, 0} ->
            true;
        {<<"eq">>, 0} ->
            true;
        {<<"!=">>, I} when I =/= 0 ->
            true;
        {<<"<>">>, I} when I =/= 0 ->
            true;
        {<<"ne">>, I} when I =/= 0 ->
            true;
        _ ->
            false
    end.

-spec extension_loaded(ephp:context_id(), line(), Name :: var_value()) -> boolean().
extension_loaded(_Context, _Line, {_, ModuleName}) ->
    Modules =
        lists:map(fun(M) ->
                     case atom_to_binary(M, utf8) of
                         <<"ephp_lib_", Module/binary>> ->
                             Module;
                         Module ->
                             Module
                     end
                  end,
                  ephp_config:get(modules, [])),
    lists:member(ModuleName, Modules).

-spec memory_get_usage(ephp:context_id(), line(), RealUsage :: var_value()) ->
                          pos_integer().
memory_get_usage(_Context, _Line, {_, false}) ->
    recon_alloc:memory(used, current);
memory_get_usage(_Context, _Line, {_, true}) ->
    recon_alloc:memory(allocated, current).

-spec memory_get_peak_usage(ephp:context_id(), line(), RealUsage :: var_value()) ->
                               pos_integer().
memory_get_peak_usage(_Context, _Line, {_, false}) ->
    recon_alloc:memory(used, max);
memory_get_peak_usage(_Context, _Line, {_, true}) ->
    recon_alloc:memory(allocated, max).

%% ----------------------------------------------------------------------------
%% Internal functions
%% ----------------------------------------------------------------------------

process_directives(Values) ->
    D = lists:foldl(fun process_directives/2, orddict:new(), Values),
    ephp_array:from_list([{K, ephp_array:from_list(V)} || {K, V} <- D]).

process_directives({K, V}, Dict) ->
    case binary:split(K, <<".">>) of
        [K] ->
            safe_append(<<"core">>, {K, V}, Dict);
        [Section, _] ->
            safe_append(Section, {K, V}, Dict)
    end.

safe_append(K, V, Dict) ->
    case orddict:is_key(K, Dict) of
        true ->
            orddict:append(K, V, Dict);
        false ->
            orddict:store(K, [V], Dict)
    end.

phpinfo_metadata() ->
    OtpRelease = list_to_binary(erlang:system_info(otp_release)),
    IniFile = filename:dirname(?PHP_INI_FILE),
    Directives = ephp_config:get_all(),
    ArrDirectives = process_directives(Directives),
    Streams =
        ephp_array:from_list(
            ephp_stream:list_streams()),
    ephp_array:from_list([{<<"version">>, ?PHP_VERSION},
                          {<<"vsn">>, get_vsn()},
                          {<<"build_date">>, get_build_date()},
                          {<<"release">>, OtpRelease},
                          {<<"path_php_ini">>, IniFile},
                          {<<"directives">>, ArrDirectives},
                          {<<"streams">>, Streams},
                          {<<"tz_version">>, ephp_datetime:get_tz_version()}]).

process_phpinfo(Format, Context, Flags) ->
    Metadata = phpinfo_metadata(),
    PHPInfo = get_file("phpinfo." ++ Format ++ ".php"),
    ephp:register_var(Context, <<"_METADATA">>, Metadata),
    ephp:register_var(Context, <<"_FLAGS">>, Flags),
    ephp:register_var(Context, <<"LICENSE">>, get_file("license")),
    {ok, false} = ephp:eval(Context, PHPInfo),
    undefined.

get_file(Name, Filename) when Name =:= "rebar3" orelse Name =:= undefined ->
    FullFilename =
        filename:join(
            code:priv_dir(ephp), Filename),
    {ok, Content} = file:read_file(FullFilename),
    Content;
get_file(Name, Filename) ->
    {ok, Sections} = escript:extract(Name, []),
    Zip = proplists:get_value(archive, Sections),
    Filter =
        fun (#zip_file{name = "ephp/priv/" ++ _}) ->
                true;
            (_) ->
                false
        end,
    {ok, Files} = zip:extract(Zip, [{file_filter, Filter}, memory]),
    NewFilename = "ephp/priv/" ++ Filename,
    proplists:get_value(NewFilename, Files).

get_file(Filename) ->
    try
        Name =
            filename:basename(
                escript:script_name()),
        get_file(Name, Filename)
    catch
        error:{badmatch, []} ->
            get_file(undefined, Filename)
    end.

-spec get_vsn() -> binary().
get_vsn() ->
    {ok, Vsn} = application:get_key(ephp, vsn),
    list_to_binary(Vsn).

-spec get_build_date() -> binary().
-ifndef(BUILD_DATE).

%% keep it only for some editors (like VSCode)
-define(BUILD_DATE, "Aug 26 2019 13:57:10").

-endif.

get_build_date() ->
    list_to_binary(?BUILD_DATE).

-spec get_os() -> binary().
get_os() ->
    %% TODO complete the list of OS
    case os:type() of
        {unix, darwin} ->
            <<"Darwin">>;
        {unix, linux} ->
            <<"Linux">>;
        {unix, freebsd} ->
            <<"FreeBSD">>;
        {win32, nt} ->
            <<"WINNT">>;
        {win32, _} ->
            <<"Windows">>
    end.

-spec get_os_family() -> binary().
get_os_family() ->
    %% TODO complete the list of OS families
    case os:type() of
        {unix, darwin} ->
            <<"OSX">>;
        {unix, linux} ->
            <<"LINUX">>;
        %% TODO Add more BSD
        {unix, freebsd} ->
            <<"BSD">>;
        %% TODO Add Solaris
        {win32, _} ->
            <<"WIN">>;
        {_, _} ->
            <<"unknown">>
    end.

-spec get_os_eol() -> binary().
get_os_eol() ->
    %% TODO change this for something more coherent :-P
    <<"\n">>.