modules/m_command: Support command input w/ reply-to argument context.

modules/client/rooms/send.cc

@@ -158,15 +158,31 @@ put__send(client &client,
 			content
 		};
 
-		const bool command
+		const bool command_regular
 		{
 			json::get<"msgtype"_>(message) == "m.text"
 			&& startswith(json::get<"body"_>(message), "\\\\")
 		};
 
+		const bool command_replying
+		{
+			json::get<"msgtype"_>(message) == "m.text"
+			&& startswith(json::get<"body"_>(message), ">")
+			&& has(json::get<"body"_>(message), "\\n\\n\\\\")
+		};
+
 		const bool echo
 		{
-			startswith(lstrip(json::get<"body"_>(message), "\\\\"), '!')
+			command_regular?
+				startswith(lstrip(json::get<"body"_>(message), "\\\\"), '!'):
+			command_replying?
+				has(json::get<"body"_>(message), "\\n\\n\\\\!"):
+				false
+		};
+
+		const bool command
+		{
+			command_regular || command_replying
 		};
 
 		if(command && !echo)
@@ -222,6 +238,27 @@ handle_command(client &client,
 		request.user_id, room.copts
 	};
 
+	const json::object content
+	{
+		request
+	};
+
+	const json::object m_relates_to
+	{
+		content["m.relates_to"]
+	};
+
+	const json::object m_in_reply_to
+	{
+		m_relates_to["m.in_reply_to"]
+	};
+
+	const json::string reply_id
+	{
+		m_in_reply_to["event_id"]?:
+			m_relates_to["event_id"]
+	};
+
 	const auto event_id
 	{
 		send(user_room, request.user_id, "ircd.cmd",
@@ -230,6 +267,7 @@ handle_command(client &client,
 			{ "body",     request["body"]  },
 			{ "room_id",  room.room_id     },
 			{ "event_id", echo_id          },
+			{ "reply_id", reply_id         },
 		})
 	};
 

modules/m_command.cc

@@ -44,7 +44,8 @@ static command_result
 execute_command(const mutable_buffer &buf,
                 const m::user &user,
                 const m::room &room,
-                const string_view &cmd);
+                const string_view &cmd,
+                const m::event::id &reply_to);
 
 void
 handle_command(const m::event &event,
@@ -82,17 +83,32 @@ try
 		content["event_id"]
 	};
 
-	const json::string &input_
+	const json::string &body
 	{
 		content.at("body")
 	};
 
-	if(!startswith(input_, "\\\\"))
+	const bool is_command
+	{
+		startswith(body, "\\\\")
+	};
+
+	const bool is_command_replying
+	{
+		startswith(body, ">")
+		&& has(body, "\\n\\n\\\\")
+	};
+
+	if(!is_command && !is_command_replying)
 		return;
 
 	// View of the command string without prefix
-	string_view input{input_};
-	input = lstrip(input, "\\\\");
+	string_view input
+	{
+		is_command_replying?
+			lstrip(split(body, "\\n\\n\\\\").second, "\\\\"):
+			lstrip(body, "\\\\")
+	};
 
 	// Determine if there's a bang after the prefix; if so the response's
 	// sender will be the user, and will be broadcast publicly to the room.
@@ -103,15 +119,30 @@ try
 		startswith(input, '!')
 	};
 
-	string_view cmd{input};
-	cmd = lstrip(cmd, '!');
+	const string_view cmd
+	{
+		lstrip(input, '!')
+	};
+
+	const json::string reply_to
+	{
+		content["reply_id"]
+	};
+
+	const auto reply_id
+	{
+		reply_to?
+			m::event::id{reply_to}:
+			m::event::id{}
+	};
 
 	log::debug
 	{
-		m::log, "Server command from %s in %s public:%b :%s",
+		m::log, "Server command from %s in %s public:%b replying:%s :%s",
 		string_view{room_id},
 		string_view{user.user_id},
 		public_response,
+		string_view{reply_id}?: "false"_sv,
 		cmd
 	};
 
@@ -122,7 +153,7 @@ try
 
 	const auto &[html, alt, msgtype]
 	{
-		execute_command(buf, user, room_id, cmd)
+		execute_command(buf, user, room_id, cmd, reply_id)
 	};
 
 	if(!html && !alt)
@@ -275,7 +306,8 @@ command_result
 execute_command(const mutable_buffer &buf,
                 const m::user &user,
                 const m::room &room,
-                const string_view &cmd)
+                const string_view &cmd,
+                const m::event::id &reply_id)
 try
 {
 	if(startswith(cmd, '#'))