%% Copyright (c) 2015, Loïc Hoguin <essen@ninenines.eu>
%%
%% Permission to use, copy, modify, and/or distribute this software for any
%% purpose with or without fee is hereby granted, provided that the above
%% copyright notice and this permission notice appear in all copies.
%%
%% THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
%% WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
%% MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
%% ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
%% WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
%% ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
%% OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

-module(spdy_SUITE).
-compile(export_all).

-import(ct_helper, [doc/1]).

%% ct.

all() -> [{group, spdy31}].

groups() -> [{spdy31, [parallel], ct_helper:all(?MODULE)}].

%% Helper functions.

wait() ->
	receive after 500 -> ok end.

down() ->
	receive {gun_down, _, _, _, _, _} ->
		ok
	after 5000 ->
		exit(timeout)
	end.

not_down() ->
	receive {gun_down, _, _, _, _, _} ->
		exit(down)
	after 0 ->
		ok
	end.

do_req_resp(ConnPid, ServerPid, ServerStreamID) ->
	StreamRef = gun:get(ConnPid, "/"),
	spdy_server:send(ServerPid, [
		{syn_reply, ServerStreamID, false, <<"200">>, <<"HTTP/1.1">>, []},
		{data, ServerStreamID, true, <<"Hello world!">>}
	]),
	receive {gun_response, _, StreamRef, _, _, _} ->
		ok
	after 5000 ->
		exit(timeout)
	end,
	ok.

%% SPDY/3.1 test suite.

goaway_on_close(_) ->
	doc("Send a GOAWAY when the client closes the connection (spdy-protocol-draft3-1 2.1)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	gun:close(ConnPid),
	wait(),
	[{goaway, 0, ok}] = spdy_server:stop(ServerPid),
	down().

goaway_on_shutdown(_) ->
	doc("Send a GOAWAY when the client closes the connection (spdy-protocol-draft3-1 2.1)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	gun:shutdown(ConnPid),
	wait(),
	[{goaway, 0, ok}] = spdy_server:stop(ServerPid),
	down().

%% @todo This probably applies to HEADERS frame or SYN_STREAM from server push.
reject_data_on_non_existing_stream(_) ->
	doc("DATA frames received for non-existing streams must be rejected with "
		"an INVALID_STREAM stream error. (spdy-protocol-draft3-1 2.2.2)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	spdy_server:send(ServerPid, [
		{data, 1, true, <<"Hello world!">>}
	]),
	wait(),
	[{rst_stream, 1, invalid_stream}] = spdy_server:stop(ServerPid).

%% @todo This probably applies to HEADERS frame or SYN_STREAM from server push.
ignore_data_on_non_existing_stream_after_goaway(_) ->
	%% Note: this is not explicitly written in the specification.
	%% However the HTTP/2 draft tells us that we can discard frames
	%% with identifiers higher than the identified last stream,
	%% which falls under this case. (draft-ietf-httpbis-http2-17 6.8)
	doc("DATA frames received for non-existing streams after a GOAWAY has been "
		"sent must be ignored. (spdy-protocol-draft3-1 2.2.2)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	gun:shutdown(ConnPid),
	spdy_server:send(ServerPid, [
		{data, 1, true, <<"Hello world!">>}
	]),
	wait(),
	[{goaway, 0, ok}] = spdy_server:stop(ServerPid),
	down().

%% @todo This probably applies to HEADERS frame or SYN_STREAM from server push.
reject_data_before_syn_reply(_) ->
	doc("A DATA frame received before a SYN_REPLY must be rejected "
		"with a PROTOCOL_ERROR stream error.  (spdy-protocol-draft3-1 2.2.2)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	_ = gun:get(ConnPid, "/"),
	spdy_server:send(ServerPid, [
		{data, 1, true, <<"Hello world!">>},
		{syn_reply, 1, false, <<"200">>, <<"HTTP/1.1">>, []}
	]),
	wait(),
	[_, {rst_stream, 1, protocol_error}] = spdy_server:stop(ServerPid).

streamid_is_odd(_) ->
	doc("Client-initiated Stream-ID must be an odd number. (spdy-protocol-draft3-1 2.3.2)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	[do_req_resp(ConnPid, ServerPid, N) || N <- lists:seq(1, 5, 2)],
	Rec = spdy_server:stop(ServerPid),
	true = length(Rec) =:= length([ok || {syn_stream, StreamID, _, _, _, _, _, _, _, _, _, _} <- Rec, StreamID rem 2 =:= 1]).

reject_streamid_0(_) ->
	doc("The Stream-ID 0 is not valid and must be rejected with a PROTOCOL_ERROR session error. (spdy-protocol-draft3-1 2.3.2)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	_ = gun:get(ConnPid, "/"),
	spdy_server:send(ServerPid, [
		{syn_stream, 0, 1, true, true, 0, <<"GET">>, <<"https">>, ["localhost:", integer_to_binary(Port)], "/a", <<"HTTP/1.1">>, []},
		{syn_reply, 1, true, <<"200">>, <<"HTTP/1.1">>, []}
	]),
	wait(),
	[_, {goaway, 0, protocol_error}] = spdy_server:stop(ServerPid),
	down().

streamid_increases_monotonically(_) ->
	doc("The Stream-ID must increase monotonically. (spdy-protocol-draft3-1 2.3.2)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	Expected = [1, 3, 5, 7, 9],
	[do_req_resp(ConnPid, ServerPid, N) || N <- Expected],
	wait(),
	Rec = spdy_server:stop(ServerPid),
	Expected = [StreamID || {syn_stream, StreamID, _, _, _, _, _, _, _, _, _, _} <- Rec].

streamid_does_not_wrap(_) ->
	doc("Stream-ID must not wrap. Reconnect when all Stream-IDs are exhausted. (spdy-protocol-draft3-1 2.3.2)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	MaxClientStreamID = 2147483647,
	sys:replace_state(ConnPid, fun({loop, State}) ->
		%% Replace the next stream_id value to the maximum allowed value.
		{loop, setelement(11, State, setelement(9, element(11, State), MaxClientStreamID))}
	end),
	do_req_resp(ConnPid, ServerPid, MaxClientStreamID),
	%% Gun has exhausted all Stream-IDs and should now reconnect.
	{ok, spdy} = gun:await_up(ConnPid),
	%% Check that the next request is on a new connection.
	_ = gun:get(ConnPid, "/"),
	[{syn_stream, 1, _, _, _, _, _, _, _, _, _, _}] = spdy_server:stop(ServerPid).

reject_syn_stream_decreasing_streamid(_) ->
	doc("Reject a decreasing Stream-ID with a PROTOCOL_ERROR session error. (spdy-protocol-draft3-1 2.3.2)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	_ = gun:get(ConnPid, "/"),
	Host = ["localhost:", integer_to_binary(Port)],
	spdy_server:send(ServerPid, [
		{syn_stream, 2, 1, true, true, 0, <<"GET">>, <<"https">>, Host, "/a", <<"HTTP/1.1">>, []},
		{syn_stream, 6, 1, true, true, 0, <<"GET">>, <<"https">>, Host, "/b", <<"HTTP/1.1">>, []},
		{syn_stream, 4, 1, true, true, 0, <<"GET">>, <<"https">>, Host, "/c", <<"HTTP/1.1">>, []},
		{syn_reply, 1, true, <<"200">>, <<"HTTP/1.1">>, []}
	]),
	wait(),
	[_, {goaway, 0, protocol_error}] = spdy_server:stop(ServerPid),
	down().

reject_stream_duplicate_streamid(_) ->
	doc("Reject duplicate Stream-ID with a PROTOCOL_ERROR session error. (spdy-protocol-draft3-1 2.3.2)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	_ = gun:get(ConnPid, "/"),
	Host = ["localhost:", integer_to_binary(Port)],
	spdy_server:send(ServerPid, [
		{syn_stream, 2, 1, true, true, 0, <<"GET">>, <<"https">>, Host, "/a", <<"HTTP/1.1">>, []},
		{syn_stream, 2, 1, true, true, 0, <<"GET">>, <<"https">>, Host, "/b", <<"HTTP/1.1">>, []},
		{syn_reply, 1, true, <<"200">>, <<"HTTP/1.1">>, []}
	]),
	wait(),
	[_, {goaway, 2, protocol_error}] = spdy_server:stop(ServerPid),
	down().

dont_send_frames_after_flag_fin(_) ->
	doc("Do not send frames after sending FLAG_FIN. (spdy-protocol-draft3-1 2.3.6)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	%% Send a POST frame with no content header so that Gun sets FLAG_FIN,
	%% then try sending data. Gun should reject this second call.
	StreamRef = gun:post(ConnPid, "/", []),
	gun:data(ConnPid, StreamRef, false, <<"Hello world!">>),
	receive {gun_error, ConnPid, StreamRef, _} ->
		ok
	after 5000 ->
		exit(timeout)
	end,
	wait(),
	[{syn_stream, _, _, _, _, _, _, _, _, _, _, _}] = spdy_server:stop(ServerPid).

allow_window_update_after_flag_fin(_) ->
	doc("WINDOW_UPDATE is allowed when the stream is half-closed. (spdy-protocol-draft3-1 2.3.6)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	_ = gun:get(ConnPid, "/"),
	spdy_server:send(ServerPid, [
		{window_update, 1, 1024}
	]),
	wait(),
	[{syn_stream, _, _, _, _, _, _, _, _, _, _, _}] = spdy_server:stop(ServerPid).

%% @todo This probably applies to HEADERS frame or SYN_STREAM from server push.
reject_data_on_half_closed_stream(_) ->
	doc("Data frames sent on a half-closed stream must be rejected "
		"with a STREAM_ALREADY_CLOSED stream error. (spdy-protocol-draft3-1 2.3.6)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	%% Send a POST frame with a content header so that Gun leaves this
	%% stream alive after the server sends the reply.
	_ = gun:post(ConnPid, "/", [{<<"content-length">>, <<"5">>}]),
	spdy_server:send(ServerPid, [
		{syn_reply, 1, true, <<"200">>, <<"HTTP/1.1">>, []},
		{data, 1, true, <<"Hello world!">>}
	]),
	wait(),
	[_, {rst_stream, 1, stream_already_closed}] = spdy_server:stop(ServerPid).

%% @todo This probably applies to HEADERS frame or SYN_STREAM from server push.
reject_data_on_closed_stream(_) ->
	doc("Data frames sent on a closed stream must be rejected "
		"with a PROTOCOL_ERROR stream error. (spdy-protocol-draft3-1 2.3.7)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	%% Send a GET frame so that the stream is closed when the server replies.
	_ = gun:get(ConnPid, "/"),
	spdy_server:send(ServerPid, [
		{syn_reply, 1, true, <<"200">>, <<"HTTP/1.1">>, []},
		{data, 1, true, <<"Hello world!">>}
	]),
	wait(),
	[_, {rst_stream, 1, protocol_error}] = spdy_server:stop(ServerPid).

%% @todo We need to test that we do the right thing when the server sends a GOAWAY.
goaway_last_good_streamid(_) ->
	doc("The GOAWAY frame must contain the Stream-ID of the last recently "
		"received stream from the remote endpoint. (spdy-protocol-draft3-1 2.4.1)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	_ = gun:get(ConnPid, "/"),
	Host = ["localhost:", integer_to_binary(Port)],
	spdy_server:send(ServerPid, [
		{syn_stream, 2, 1, true, true, 0, <<"GET">>, <<"https">>, Host, "/a", <<"HTTP/1.1">>, []},
		{syn_stream, 4, 1, true, true, 0, <<"GET">>, <<"https">>, Host, "/c", <<"HTTP/1.1">>, []},
		{syn_stream, 6, 1, true, true, 0, <<"GET">>, <<"https">>, Host, "/b", <<"HTTP/1.1">>, []},
		{syn_reply, 0, true, <<"200">>, <<"HTTP/1.1">>, []}
	]),
	wait(),
	[_, {goaway, 6, protocol_error}] = spdy_server:stop(ServerPid),
	down().

dont_send_rst_stream_on_rst_stream(_) ->
	doc("An endpoint must not send an RST_STREAM in response to an RST_STREAM. (spdy-protocol-draft3-1 2.4.2)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	_ = gun:get(ConnPid, "/"),
	spdy_server:send(ServerPid, [
		{rst_stream, 1, refused_stream}
	]),
	wait(),
	%% No RST_STREAM was received; only SYN_STREAM.
	[_] = spdy_server:stop(ServerPid),
	not_down().

coalesce_multiple_identical_rst_stream(_) ->
	doc("Do not send multiple identical RST_STREAM in succession. (spdy-protocol-draft3-1 2.4.2)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	spdy_server:send(ServerPid, [
		{data, 1, true, <<"Hello ">>},
		{data, 1, true, <<"world!">>}
	]),
	wait(),
	[{rst_stream, 1, invalid_stream}] = spdy_server:stop(ServerPid).

%% @todo I am not sure how to adequately test that we don't send bad flags.
syn_stream_ignore_unknown_flags(_) ->
	%% Note: this is not explicitly written in the specification.
	%% However the HTTP/2 draft tells us to ignore unknown flags.
	%% (draft-ietf-httpbis-http2-17 4.1)
	doc("Unknown flags must be ignored. (spdy-protocol-draft3-1 2.6.1)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	_ = gun:get(ConnPid, "/"),
	%% Build a SYN_STREAM frame with all flag bits set to 1.
	<< Before:32/bits, _:8, After/bits >> = iolist_to_binary(cow_spdy:syn_stream(cow_spdy:deflate_init(),
		2, 1, true, true, 0, <<"GET">>, <<"https">>, ["localhost:", integer_to_binary(Port)], "/a", <<"HTTP/1.1">>, [])),
	Frame = << Before/bits, 1:1, 1:1, 1:1, 1:1, 1:1, 1:1, 1:1, 1:1, After/bits >>,
	spdy_server:send_raw(ServerPid, Frame),
	wait(),
	[_] = spdy_server:stop(ServerPid).

reject_associated_to_streamid_0(_) ->
	doc("A non-zero Associated-To-Stream-ID sent by the server must "
		"be rejected with a PROTOCOL_ERROR session error. (spdy-protocol-draft3-1 2.6.1)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	_ = gun:get(ConnPid, "/"),
	Host = ["localhost:", integer_to_binary(Port)],
	spdy_server:send(ServerPid, [
		{syn_stream, 2, 1, true, true, 0, <<"GET">>, <<"https">>, Host, "/a", <<"HTTP/1.1">>, []},
		{syn_stream, 4, 1, true, true, 0, <<"GET">>, <<"https">>, Host, "/c", <<"HTTP/1.1">>, []},
		{syn_stream, 6, 0, true, true, 0, <<"GET">>, <<"https">>, Host, "/b", <<"HTTP/1.1">>, []},
		{syn_reply, 1, true, <<"200">>, <<"HTTP/1.1">>, []}
	]),
	wait(),
	[_, {goaway, 4, protocol_error}] = spdy_server:stop(ServerPid),
	down().

syn_reply_ignore_unknown_flags(_) ->
	%% Note: this is not explicitly written in the specification.
	%% However the HTTP/2 draft tells us to ignore unknown flags.
	%% (draft-ietf-httpbis-http2-17 4.1)
	doc("Unknown flags must be ignored. (spdy-protocol-draft3-1 2.6.2)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	_ = gun:get(ConnPid, "/"),
	%% Build a SYN_REPLY frame with all flag bits set to 1.
	<< Before:32/bits, _:8, After/bits >> = iolist_to_binary(cow_spdy:syn_reply(cow_spdy:deflate_init(),
		1, true, <<"200">>, <<"HTTP/1.1">>, [])),
	Frame = << Before/bits, 1:1, 1:1, 1:1, 1:1, 1:1, 1:1, 1:1, 1:1, After/bits >>,
	spdy_server:send_raw(ServerPid, Frame),
	wait(),
	[_] = spdy_server:stop(ServerPid).

reject_duplicate_syn_reply(_) ->
	doc("Reception of multiple SYN_REPLY for the same Stream-ID must "
		"be rejected with a STREAM_IN_USE stream error. (spdy-protocol-draft3-1 2.6.2)"),
	{ok, ServerPid, Port} = spdy_server:start_link(),
	{ok, ConnPid} = gun:open("localhost", Port, #{transport=>ssl}),
	{ok, spdy} = gun:await_up(ConnPid),
	_ = gun:get(ConnPid, "/"),
	Host = ["localhost:", integer_to_binary(Port)],
	spdy_server:send(ServerPid, [
		{syn_reply, 1, false, <<"200">>, <<"HTTP/1.1">>, []},
		{syn_reply, 1, false, <<"200">>, <<"HTTP/1.1">>, []}
	]),
	wait(),
	[_, {rst_stream, 1, stream_in_use}] = spdy_server:stop(ServerPid).