construct/modules/m_user_mitsein.cc

// Matrix Construct
//
// Copyright (C) Matrix Construct Developers, Authors & Contributors
// Copyright (C) 2016-2019 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.

ircd::mapi::header
IRCD_MODULE
{
	"Matrix rooms in common between users."
};

IRCD_MODULE_EXPORT
ircd::m::user::mitsein::mitsein(const m::user &user)
:user{user}
{
}

bool
IRCD_MODULE_EXPORT
ircd::m::user::mitsein::has(const m::user &other,
                            const string_view &membership)
const
{
	// Return true if broken out of loop.
	return !for_each(other, membership, []
	(const m::room &, const string_view &)
	{
		// Break out of loop at first shared room
		return false;
	});
}

size_t
IRCD_MODULE_EXPORT
ircd::m::user::mitsein::count(const string_view &membership)
const
{
	size_t ret{0};
	for_each(membership, [&ret](const m::user &)
	{
		++ret;
		return true;
	});

	return ret;
}

size_t
IRCD_MODULE_EXPORT
ircd::m::user::mitsein::count(const m::user &user,
                              const string_view &membership)
const
{
	size_t ret{0};
	for_each(user, membership, [&ret](const m::room &, const string_view &)
	{
		++ret;
		return true;
	});

	return ret;
}

bool
IRCD_MODULE_EXPORT
ircd::m::user::mitsein::for_each(const closure_bool &closure)
const
{
	return for_each(string_view{}, closure);
}

bool
IRCD_MODULE_EXPORT
ircd::m::user::mitsein::for_each(const string_view &membership,
                                 const closure_bool &closure)
const
{
	const m::user::rooms rooms
	{
		user
	};

	// here we gooooooo :/
	///TODO: ideal: db schema
	///TODO: minimally: custom alloc?
	std::set<std::string, std::less<>> seen;
	return rooms.for_each(membership, rooms::closure_bool{[&membership, &closure, &seen]
	(m::room room, const string_view &)
	{
		static const event::fetch::opts fopts
		{
			event::keys::include {"state_key"}
		};

		room.fopts = &fopts;
		const m::room::members members
		{
			room
		};

		return members.for_each(membership, [&seen, &closure]
		(const user::id &other)
		{
			const auto it
			{
				seen.lower_bound(other)
			};

			if(it != end(seen) && *it == other)
				return true;

			seen.emplace_hint(it, std::string{other});
			return closure(m::user{other});
		});
	}});
}

bool
IRCD_MODULE_EXPORT
ircd::m::user::mitsein::for_each(const m::user &user,
                                 const rooms::closure_bool &closure)
const
{
	return for_each(user, string_view{}, closure);
}

bool
IRCD_MODULE_EXPORT
ircd::m::user::mitsein::for_each(const m::user &user,
                                 const string_view &membership,
                                 const rooms::closure_bool &closure)
const
{
	const m::user::rooms our_rooms{this->user};
	const m::user::rooms their_rooms{user};
	const bool use_our
	{
		our_rooms.count() <= their_rooms.count()
	};

	const m::user::rooms &rooms
	{
		use_our? our_rooms : their_rooms
	};

	const string_view &test_key
	{
		use_our? user.user_id : this->user.user_id
	};

	return rooms.for_each(membership, rooms::closure_bool{[&membership, &closure, &test_key]
	(const m::room &room, const string_view &)
	{
		if(!room.has("m.room.member", test_key))
			return true;

		return closure(room, membership);
	}});
}