/**
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */
#ifndef CONSUMER_HPP_
#define CONSUMER_HPP_

#include <boost/date_time/posix_time/ptime.hpp>
#include <iostream>
#include <pulsar/BrokerConsumerStats.h>
#include <pulsar/ConsumerConfiguration.h>
#pragma GCC visibility push(default)


namespace pulsar {
class PulsarWrapper;
class ConsumerImplBase;
class PulsarFriend;
/**
 *
 */
class Consumer {
 public:
    /**
     * Construct an uninitialized consumer object
     */
    Consumer();

    /**
     * @return the topic this consumer is subscribed to
     */
    const std::string& getTopic() const;

    /**
     * @return the consumer name
     */
    const std::string& getSubscriptionName() const;

    /**
     * Unsubscribe the current consumer from the topic.
     *
     * This method will block until the operation is completed. Once the consumer is
     * unsubscribed, no more messages will be received and subsequent new messages
     * will not be retained for this consumer.
     *
     * This consumer object cannot be reused.
     *
     * @see asyncUnsubscribe
     * @return Result::ResultOk if the unsubscribe operation completed successfully
     * @return Result::ResultError if the unsubscribe operation failed
     */
    Result unsubscribe();

    /**
     * Asynchronously unsubscribe the current consumer from the topic.
     *
     * This method will block until the operation is completed. Once the consumer is
     * unsubscribed, no more messages will be received and subsequent new messages
     * will not be retained for this consumer.
     *
     * This consumer object cannot be reused.
     *
     * @param callback the callback to get notified when the operation is complete
     */
    void unsubscribeAsync(ResultCallback callback);

    /**
     * Receive a single message.
     *
     * If a message is not immediately available, this method will block until a new
     * message is available.
     *
     * @param msg a non-const reference where the received message will be copied
     * @return ResultOk when a message is received
     * @return ResultInvalidConfiguration if a message listener had been set in the configuration
     */
    Result receive(Message& msg);

    /**
     *
     * @param msg a non-const reference where the received message will be copied
     * @param timeoutMs the receive timeout in milliseconds
     * @return ResultOk if a message was received
     * @return ResultTimeout if the receive timeout was triggered
     * @return ResultInvalidConfiguration if a message listener had been set in the configuration
     */
    Result receive(Message& msg, int timeoutMs);

    /**
     * Acknowledge the reception of a single message.
     *
     * This method will block until an acknowledgement is sent to the broker. After
     * that, the message will not be re-delivered to this consumer.
     *
     * @see asyncAcknowledge
     * @param message the message to acknowledge
     * @return ResultOk if the message was successfully acknowledged
     * @return ResultError if there was a failure
     */
    Result acknowledge(const Message& message);
    Result acknowledge(const MessageId& messageId);

    /**
     * Asynchronously acknowledge the reception of a single message.
     *
     * This method will initiate the operation and return immediately. The provided callback
     * will be triggered when the operation is complete.
     *
     * @param message the message to acknowledge
     * @param callback callback that will be triggered when the message has been acknowledged
     */
    void acknowledgeAsync(const Message& message, ResultCallback callback);
    void acknowledgeAsync(const MessageId& messageID, ResultCallback callback);

    /**
     * Acknowledge the reception of all the messages in the stream up to (and including)
     * the provided message.
     *
     * This method will block until an acknowledgement is sent to the broker. After
     * that, the messages will not be re-delivered to this consumer.
     *
     * Cumulative acknowledge cannot be used when the consumer type is set to ConsumerShared.
     *
     * It's equivalent to calling asyncAcknowledgeCumulative(const Message&, ResultCallback) and
     * waiting for the callback to be triggered.
     *
     * @param message the last message in the stream to acknowledge
     * @return ResultOk if the message was successfully acknowledged. All previously delivered messages for this topic are also acknowledged.
     * @return ResultError if there was a failure
     */
    Result acknowledgeCumulative(const Message& message);
    Result acknowledgeCumulative(const MessageId& messageId);

    /**
     * Asynchronously acknowledge the reception of all the messages in the stream up to (and
     * including) the provided message.
     *
     * This method will initiate the operation and return immediately. The provided callback
     * will be triggered when the operation is complete.
     *
     * @param message the message to acknowledge
     * @param callback callback that will be triggered when the message has been acknowledged
     */
    void acknowledgeCumulativeAsync(const Message& message, ResultCallback callback);
    void acknowledgeCumulativeAsync(const MessageId& messageId, ResultCallback callback);

    Result close();

    void closeAsync(ResultCallback callback);

    /*
     * Pause receiving messages via the messageListener, till resumeMessageListener() is called.
     */
    Result pauseMessageListener();

    /*
     * Resume receiving the messages via the messageListener.
     * Asynchronously receive all the messages enqueued from time pauseMessageListener() was called.
     */
    Result resumeMessageListener();

    /**
     * Redelivers all the unacknowledged messages. In Failover mode, the request is ignored if the consumer is not
     * active for the given topic. In Shared mode, the consumers messages to be redelivered are distributed across all
     * the connected consumers. This is a non blocking call and doesn't throw an exception. In case the connection
     * breaks, the messages are redelivered after reconnect.
     */
    void redeliverUnacknowledgedMessages();

    /**
     * Gets Consumer Stats from broker.
     * The stats are cached for 30 seconds, if a call is made before the stats returned by the previous call expires
     * then cached data will be returned. BrokerConsumerStats::isValid() function can be used to check if the stats are
     * still valid.
     *
     * @param brokerConsumerStats - if the function returns ResultOk, this object will contain consumer stats
     *
     * @note This is a blocking call with timeout of thirty seconds.
     */
    Result getBrokerConsumerStats(BrokerConsumerStats& brokerConsumerStats);

    /**
    * Asynchronous call to gets Consumer Stats from broker.
    * The stats are cached for 30 seconds, if a call is made before the stats returned by the previous call expires
    * then cached data will be returned. BrokerConsumerStats::isValid() function can be used to check if the stats are
    * still valid.
    *
    * @param callback - callback function to get the brokerConsumerStats,
    *                   if result is ResultOk then the brokerConsumerStats will be populated
    */
    void getBrokerConsumerStatsAsync(BrokerConsumerStatsCallback callback);
private:
    typedef boost::shared_ptr<ConsumerImplBase> ConsumerImplBasePtr;
    ConsumerImplBasePtr impl_;
    explicit Consumer(ConsumerImplBasePtr);

    friend class PulsarFriend;
    friend class PulsarWrapper;
    friend class PartitionedConsumerImpl;
    friend class ConsumerImpl;
    friend class ClientImpl;
    friend class ConsumerTest;
};

}

#pragma GCC visibility pop

#endif /* CONSUMER_HPP_ */