// 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.

#pragma once
#define HAVE_IRCD_M_KEYS_H

namespace ircd::m
{
	struct keys;

	bool expired(const m::keys &);
	bool verify(const m::keys &, std::nothrow_t) noexcept;
	void verify(const m::keys &);

	std::ostream &pretty(std::ostream &, const m::keys &);
	std::ostream &pretty_oneline(std::ostream &, const m::keys &);
}

/// Contains the public keys and proof of identity for a remote server.
///
/// A user who wishes to verify a signature from a remote server must have
/// the name of the server (origin) and the key_id. Calling the appropriate
/// static function of this class will attempt to fetch the key from the db
/// or make network requests, with valid response being saved to the db. Keys
/// are thus managed internally so the user doesn't supply a buffer or ever
/// construct this object; instead this object backed by internal db data is
/// presented in the supplied synchronous closure.
///
/// 2.2.1.1 Publishing Keys
///
/// Key                 Type, Description
/// server_name         String, DNS name of the homeserver.
/// verify_keys         Object, Public keys of the homeserver for verifying digital signatures.
/// old_verify_keys     Object, The public keys that the server used to use and when it stopped using them.
/// signatures          Object, Digital signatures for this object signed using the verify_keys.
/// valid_until_ts      Integer, POSIX timestamp when the list of valid keys should be refreshed.
///
struct ircd::m::keys
:json::tuple
<
	json::property<name::old_verify_keys, json::object>,
	json::property<name::server_name, json::string>,
	json::property<name::signatures, json::object>,
	json::property<name::tls_fingerprints, json::array>,
	json::property<name::valid_until_ts, time_t>,
	json::property<name::verify_keys, json::object>
>
{
	struct cache;

	using pdus = vector_view<const event>;
	using queries = vector_view<const fed::key::server_key>; // <server, key_id>
	using closure = std::function<void (const json::object &)>;
	using closure_bool = std::function<bool (const json::object &)>;

	static bool get(const queries &, const closure_bool &);
	static bool get(const string_view &server_name, const closure &);
	static bool get(const string_view &server_name, const string_view &key_id, const closure &);
	static bool query(const string_view &remote, const queries &, const closure_bool &, const mutable_buffer &, const bool dynamic = false);
	static bool query(const string_view &remote, const queries &, const closure_bool &);
	static size_t fetch(const queries &);
	static size_t fetch(const pdus &);

	using super_type::tuple;
	using super_type::operator=;
};

struct ircd::m::keys::cache
{
	static bool for_each(const string_view &server, const closure_bool &);
	static bool has(const string_view &server, const string_view &key_id);
	static bool get(const string_view &server, const string_view &key_id, const closure &);
	static size_t set(const json::object &keys);
};