-module(opener_ffi).

-export([get_os/0, exec/2]).

get_os() ->
    case os:type() of
        {win32, _} ->
            nt;
        {unix, darwin} ->
            darwin;
        {unix, linux} ->
            linux;
        {_, _} ->
            unknown
    end.

%% This function has been vendored and modified from the original source available
%% at: https://github.com/lustre-labs/dev-tools/blob/91d89bfa8c6695846f03f700ec8b741ebaabfbe8/src/lustre_dev_tools_ffi.erl
%%
%% That work is licensed under the MIT license.
%% A full version that license text is made available below:
%%
%% 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.
%%
exec(Command, Args) ->
  Command_ = binary_to_list(Command),
  Args_ = lists:map(fun(Arg) -> binary_to_list(Arg) end, Args),

  Name = {spawn_executable, os:find_executable(Command_)},

  Port = open_port(
           Name,
           [
            exit_status,
            binary,
            hide,
            stream,
            eof,
            stderr_to_stdout,
            {args, Args_}]),

  do_exec(Port, []).

%% This function has been vendored and modified from the original source available
%% at: https://github.com/lustre-labs/dev-tools/blob/91d89bfa8c6695846f03f700ec8b741ebaabfbe8/src/lustre_dev_tools_ffi.erl
%%
%% That work is licensed under the MIT license.
%% A full version that license text is made available below:
%%
%% 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.
%%
%% Helper function to handle the execution of the command and collect output.
%%
%% @param Port The port used for communication with the external process.
%% @param Acc An accumulator for collecting output data.
%%
%% @return A tuple indicating success or failure of the command execution.
do_exec(Port, Acc) ->
  receive
    {Port, {data, Data}} ->
      do_exec(Port, [Data | Acc]);
    {Port, {exit_status, 0}} ->
      port_close(Port),
      {ok, list_to_binary(lists:reverse(Acc))};
    {Port, {exit_status, Code}} -> 
      port_close(Port),
      {error, {Code, list_to_binary(lists:reverse(Acc))}}
  end.