// Matrix Construct
//
// Copyright (C) Matrix Construct Developers, Authors & Contributors
// Copyright (C) 2016-2018 Jason Volk <jason@zemos.net>
//
// 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 is present in all copies. The
// full license for this software is available in the LICENSE file.

using namespace ircd;

mapi::header
IRCD_MODULE
{
	"Federation :Send join event"
};

const string_view
send_join_description
{R"(

Inject a join event into a room originating from a server without any joined
users in that room.

)"};

resource
send_join_resource
{
	"/_matrix/federation/v1/send_join/",
	{
		send_join_description,
		resource::DIRECTORY
	}
};

resource::response
put__send_join(client &client,
               const resource::request &request)
{
	if(request.parv.size() < 1)
		throw m::NEED_MORE_PARAMS
		{
			"room_id path parameter required"
		};

	m::room::id::buf room_id
	{
		url::decode(room_id, request.parv[0])
	};

	if(request.parv.size() < 2)
		throw m::NEED_MORE_PARAMS
		{
			"event_id path parameter required"
		};

	m::event::id::buf event_id
	{
		url::decode(event_id, request.parv[1])
	};

	const m::event event
	{
		request
	};

	if(at<"event_id"_>(event) != event_id)
		throw m::error
		{
			http::NOT_MODIFIED, "M_MISMATCH_EVENT_ID",
			"ID of event in request body does not match path parameter."
		};

	if(at<"room_id"_>(event) != room_id)
		throw m::error
		{
			http::NOT_MODIFIED, "M_MISMATCH_ROOM_ID",
			"ID of room in request body does not match path parameter."
		};

	if(json::get<"type"_>(event) != "m.room.member")
		throw m::error
		{
			http::NOT_MODIFIED, "M_INVALID_TYPE",
			"Event type must be m.room.member"
		};

	if(unquote(json::get<"content"_>(event).get("membership")) != "join")
		throw m::error
		{
			http::NOT_MODIFIED, "M_INVALID_CONTENT_MEMBERSHIP",
			"Event content.membership state must be 'join'."
		};

	if(json::get<"origin"_>(event) != request.origin)
		throw m::error
		{
			http::NOT_MODIFIED, "M_MISMATCH_ORIGIN",
			"Event origin must be you."
		};

	if(m::room::server_acl::enable_write && !m::room::server_acl::check(room_id, request.node_id))
		throw m::ACCESS_DENIED
		{
			"You are not permitted by the room's server access control list."
		};

	m::vm::opts vmopts;
	vmopts.non_conform.set(m::event::conforms::MISSING_PREV_STATE);
	m::vm::eval eval
	{
		event, vmopts
	};

	const m::room::state state
	{
		room_id
	};

	const m::event::auth::chain auth_chain
	{
		m::head_idx(room_id)
	};

	resource::response::chunked response
	{
		client, http::OK
	};

	json::stack out
	{
		response.buf, response.flusher()
	};

	json::stack::array top
	{
		out
	};

	// First element is the 200
	top.append(json::value(200L));

	// Second element is the object
	json::stack::object data{top};

	// Required. The resident server's DNS name.
	json::stack::member
	{
		data, "origin", my_host()
	};

	// auth_chain
	if(request.query.get<bool>("auth_chain", true))
	{
		json::stack::array auth_chain_a
		{
			data, "auth_chain"
		};

		auth_chain.for_each(m::event::closure_idx_bool{[&auth_chain_a]
		(const m::event::idx &event_idx)
		{
			const m::event::fetch event
			{
				event_idx, std::nothrow
			};

			if(event.valid)
				auth_chain_a.append(event);

			return true;
		}});
	}

	// state
	if(request.query.get<bool>("state", true))
	{
		json::stack::array state_a
		{
			data, "state"
		};

		state.for_each([&state_a]
		(const m::event &event)
		{
			state_a.append(event);
		});
	}

	return response;
}

resource::method
method_put
{
	send_join_resource, "PUT", put__send_join,
	{
		method_put.VERIFY_ORIGIN
	}
};