#include <DB/Interpreters/Cluster.h>
#include <Poco/Util/AbstractConfiguration.h>
#include <Poco/Util/Application.h>
#include <Poco/Net/NetworkInterface.h>
#include <boost/bind.hpp>

namespace DB
{


Cluster::Address::Address(const String & config_prefix)
{
	Poco::Util::AbstractConfiguration & config = Poco::Util::Application::instance().config();
	host_port = Poco::Net::SocketAddress(config.getString(config_prefix + ".host"),
		config.getInt(config_prefix + ".port"));

	user = config.getString(config_prefix + ".user", "default");
	password = config.getString(config_prefix + ".password", "");
}

Cluster::Address::Address(const String & host, const int port, const String & config_prefix)
: host_port(host, port)
{
	Poco::Util::AbstractConfiguration & config = Poco::Util::Application::instance().config();

	user = config.getString(config_prefix + ".user", "default");
	password = config.getString(config_prefix + ".password", "");
}

Cluster::Address::Address(const String & host_port_, const String & user_, const String & password_)
	: user(user_), password(password_)
{
	UInt16 default_port = Poco::Util::Application::instance().config().getInt("tcp_port", 0);

	/// Похоже на то, что строка host_port_ содержит порт. Если условие срабатывает - не обязательно значит, что порт есть (пример: [::]).
	if (nullptr != strchr(host_port_.c_str(), ':') || !default_port)
		host_port = Poco::Net::SocketAddress(host_port_);
	else
		host_port = Poco::Net::SocketAddress(host_port_, default_port);
}


Clusters::Clusters(const Settings & settings, const DataTypeFactory & data_type_factory, const String & config_name)
{
	Poco::Util::AbstractConfiguration & config = Poco::Util::Application::instance().config();
	Poco::Util::AbstractConfiguration::Keys config_keys;
	config.keys(config_name, config_keys);

	for (Poco::Util::AbstractConfiguration::Keys::const_iterator it = config_keys.begin(); it != config_keys.end(); ++it)
		impl.emplace(std::piecewise_construct,
			std::forward_as_tuple(*it),
			std::forward_as_tuple(settings, data_type_factory, config_name + "." + *it));
}


Cluster::Cluster(const Settings & settings, const DataTypeFactory & data_type_factory, const String & cluster_name):
	local_nodes_num(0)
{
	Poco::Util::AbstractConfiguration & config = Poco::Util::Application::instance().config();
	Poco::Util::AbstractConfiguration::Keys config_keys;
	config.keys(cluster_name, config_keys);

	String config_prefix = cluster_name + ".";

	for (auto it = config_keys.begin(); it != config_keys.end(); ++it)
	{
		if (0 == strncmp(it->c_str(), "node", strlen("node")))
		{
			const auto & prefix = config_prefix + *it;
			const auto & host = config.getString(prefix + ".host");
			const auto port = config.getInt(prefix + ".port");
			const auto weight = config.getInt(prefix + ".weight", 1);

			addresses.emplace_back(host, port, prefix);
			slot_to_shard.insert(std::end(slot_to_shard), weight, shard_info_vec.size());
			shard_info_vec.push_back({host + ':' + std::to_string(port), weight});
		}
		else if (0 == strncmp(it->c_str(), "shard", strlen("shard")))
		{
			Poco::Util::AbstractConfiguration::Keys replica_keys;
			config.keys(config_prefix + *it, replica_keys);

			addresses_with_failover.push_back(Addresses());
			Addresses & replica_addresses = addresses_with_failover.back();

			const auto & partial_prefix = config_prefix + *it + ".";
			const auto weight = config.getInt(partial_prefix + ".weight", 1);
			std::string dir_name{};

			auto first = true;
			for (auto jt = replica_keys.begin(); jt != replica_keys.end(); ++jt)
			{
				if (0 == strncmp(jt->data(), "weight", strlen("weight")))
					continue;

				if (0 == strncmp(jt->c_str(), "replica", strlen("replica")))
				{
					const auto & prefix = partial_prefix + *jt;
					const auto & host = config.getString(prefix + ".host");
					const auto port = config.getInt(prefix + ".port");

					replica_addresses.emplace_back(host, port, prefix);
					dir_name += (first ? "" : ",") + host + ':' + std::to_string(port);

					if (first) first = false;
				}
				else
					throw Exception("Unknown element in config: " + *jt, ErrorCodes::UNKNOWN_ELEMENT_IN_CONFIG);
			}

			slot_to_shard.insert(std::end(slot_to_shard), weight, shard_info_vec.size());
			shard_info_vec.push_back({dir_name, weight});
		}
		else
			throw Exception("Unknown element in config: " + *it, ErrorCodes::UNKNOWN_ELEMENT_IN_CONFIG);
	}

	if (!addresses_with_failover.empty() && !addresses.empty())
			throw Exception("There must be either 'node' or 'shard' elements in config", ErrorCodes::EXCESSIVE_ELEMENT_IN_CONFIG);

		if (addresses_with_failover.size())
		{
			for (AddressesWithFailover::const_iterator it = addresses_with_failover.begin(); it != addresses_with_failover.end(); ++it)
			{
				ConnectionPools replicas;
				replicas.reserve(it->size());

				bool has_local_replics = false;
				for (Addresses::const_iterator jt = it->begin(); jt != it->end(); ++jt)
				{
					if (isLocal(*jt))
					{
						has_local_replics = true;
						break;
					}
					else
					{
						replicas.push_back(new ConnectionPool(
							settings.distributed_connections_pool_size,
							jt->host_port.host().toString(), jt->host_port.port(), "", jt->user, jt->password, data_type_factory, "server", Protocol::Compression::Enable,
							saturate(settings.connect_timeout_with_failover_ms, settings.limits.max_execution_time),
							saturate(settings.receive_timeout, settings.limits.max_execution_time),
							saturate(settings.send_timeout, settings.limits.max_execution_time)));
					}
				}

				if (has_local_replics)
					++local_nodes_num;
				else
					pools.push_back(new ConnectionPoolWithFailover(replicas, settings.load_balancing, settings.connections_with_failover_max_tries));
			}
		}
		else if (addresses.size())
		{
			for (Addresses::const_iterator it = addresses.begin(); it != addresses.end(); ++it)
			{
				if (isLocal(*it))
				{
					++local_nodes_num;
				}
				else
				{
					pools.push_back(new ConnectionPool(
						settings.distributed_connections_pool_size,
						it->host_port.host().toString(), it->host_port.port(), "", it->user, it->password, data_type_factory, "server", Protocol::Compression::Enable,
						saturate(settings.connect_timeout, settings.limits.max_execution_time),
						saturate(settings.receive_timeout, settings.limits.max_execution_time),
						saturate(settings.send_timeout, settings.limits.max_execution_time)));
				}
			}
		}
		else
			throw Exception("No addresses listed in config", ErrorCodes::NO_ELEMENTS_IN_CONFIG);
}


Cluster::Cluster(const Settings & settings, const DataTypeFactory & data_type_factory, std::vector< std::vector<String> > names,
				 const String & username, const String & password): local_nodes_num(0)
{
	for (size_t i = 0; i < names.size(); ++i)
	{
		Addresses current;
		for (size_t j = 0; j < names[i].size(); ++j)
			current.push_back(Address(names[i][j], username, password));
		addresses_with_failover.push_back(current);
	}

	for (AddressesWithFailover::const_iterator it = addresses_with_failover.begin(); it != addresses_with_failover.end(); ++it)
	{
		ConnectionPools replicas;
		replicas.reserve(it->size());

		for (Addresses::const_iterator jt = it->begin(); jt != it->end(); ++jt)
		{
			replicas.push_back(new ConnectionPool(
				settings.distributed_connections_pool_size,
				jt->host_port.host().toString(), jt->host_port.port(), "", jt->user, jt->password, data_type_factory, "server", Protocol::Compression::Enable,
				saturate(settings.connect_timeout_with_failover_ms, settings.limits.max_execution_time),
				saturate(settings.receive_timeout, settings.limits.max_execution_time),
				saturate(settings.send_timeout, settings.limits.max_execution_time)));
		}
		pools.push_back(new ConnectionPoolWithFailover(replicas, settings.load_balancing, settings.connections_with_failover_max_tries));
	}
}


Poco::Timespan Cluster::saturate(const Poco::Timespan & v, const Poco::Timespan & limit)
{
	if (limit.totalMicroseconds() == 0)
		return v;
	else
		return v > limit ? limit : v;
}


bool Cluster::isLocal(const Address & address)
{
	///	Если среди реплик существует такая, что:
	/// - её порт совпадает с портом, который слушает сервер;
	/// - её хост резолвится в набор адресов, один из которых совпадает с одним из адресов сетевых интерфейсов сервера
	/// то нужно всегда ходить на этот шард без межпроцессного взаимодействия
	UInt16 clickhouse_port = Poco::Util::Application::instance().config().getInt("tcp_port", 0);
	static Poco::Net::NetworkInterface::NetworkInterfaceList interfaces = Poco::Net::NetworkInterface::list();

	if (clickhouse_port == address.host_port.port() &&
		interfaces.end() != std::find_if(interfaces.begin(), interfaces.end(),
			[&](const Poco::Net::NetworkInterface & interface) { return interface.address() == address.host_port.host(); }))
	{
		LOG_INFO(&Poco::Util::Application::instance().logger(), "Replica with address " << address.host_port.toString() << " will be processed as local.");
		return true;
	}
	return false;
}

}