libcapsclient/libs/gempa/caps/encoderfactory.h

/***************************************************************************
 * Copyright (C) 2016 by gempa GmbH                                        *
 *                                                                         *
 * All Rights Reserved.                                                    *
 *                                                                         *
 * NOTICE: All information contained herein is, and remains                *
 * the property of gempa GmbH and its suppliers, if any. The intellectual  *
 * and technical concepts contained herein are proprietary to gempa GmbH   *
 * and its suppliers.                                                      *
 * Dissemination of this information or reproduction of this material      *
 * is strictly forbidden unless prior written permission is obtained       *
 * from gempa GmbH.                                                        *
 ***************************************************************************/

#ifndef GEMPA_CAPS_ENCODERFACTORY_H
#define GEMPA_CAPS_ENCODERFACTORY_H

#include "mseed/encoder.h"

#include <gempa/caps/packet.h>

namespace Gempa {
namespace CAPS {

/**
 * @brief Abstract base class of the encoder factory. Each
 * derived class must implement the create and the
 * supportsRecord method.
 */
class EncoderFactory {
	public:
		EncoderFactory();
		virtual ~EncoderFactory();
		/**
		 * @brief Creates encoder from given parameter set
		 * @param networkCode The nework code
		 * @param stationCode The station code
		 * @param locationCode The location code
		 * @param channelCode The channel code
		 * @param dt The data encoding
		 * @param samplingFrequencyNumerator The numerator
		 * @param samplingFrequencyDenominator The denominator
		 * @param samplingFrequencyDenominator The timing quality
		 * @return The encoder object or NULL if creation fails
		 */
		virtual Encoder* create(const std::string &networkCode,
		                        const std::string &stationCode,
		                        const std::string &locationCode,
		                        const std::string &channelCode,
		                        int dt,
		                        int samplingFrequencyNumerator,
		                        int samplingFrequencyDenominator) = 0;

		/**
		 * @brief Checks if an encoder factory
		 * supports the given record.
		 * @param rec The record to check
		 * @return True if the data type is supported
		 */
		virtual bool supportsRecord(DataRecord *rec) = 0;

		/**
		 * @brief Returns a human readable error description
		 * of the last error occured.
		 * @return Error description
		 */
		const std::string& errorString() const;

	protected:
		std::string    _errorString;
};


/**
 * @brief Base class for all MSEED encoders
 */
class MSEEDEncoderFactory : public EncoderFactory {
	public:
		MSEEDEncoderFactory();

		/**
		 * @brief Sets the volume logical record length expressed as a
		 * power of 2. A 512 byte record would be 9.
		 * @param recLen The record length expressed as a power of 2
		 * @return True if the record length is valid
		 */
		bool setRecordLength(unsigned int recordLength);

	protected:
		uint8_t _recordLength;
};

/**
 * @brief Implements a general Steim encoder factory
 * interface which implements the supportsRecord method
 * only.
 */
class SteimEncoderFactory : public MSEEDEncoderFactory  {
	public:
		/**
		 * @brief Checks if an encoder factory
		 * supports the given record. In case of data type float or double we
		 * return true but the values will casted implicitly to int32.
		 * @param rec The record to check
		 * @return True if the data type is supported
		 */
		bool supportsRecord(DataRecord *rec);
};


/**
 * @brief The IdentiyEncoderFactory class implements the
 * encoder factory interface and supports the creation of
 * identiy encoders.
 */
class IdentityEncoderFactory : public MSEEDEncoderFactory {
	public:
		Encoder* create(const std::string &networkCode,
		                const std::string &stationCode,
		                const std::string &locationCode,
		                const std::string &channelCode,
		                int dt,
		                int samplingFrequencyNumerator,
		                int samplingFrequencyDenominator);
		bool supportsRecord(DataRecord *rec);
};


/**
 * @brief The Steim1EncoderFactory class implements the
 * encoder factory interface and supports the creation of
 * Steim2 encoders.
 */
class Steim1EncoderFactory : public SteimEncoderFactory {
	public:
		Encoder* create(const std::string &networkCode,
		                const std::string &stationCode,
		                const std::string &locationCode,
		                const std::string &channelCode,
		                int dt,
		                int samplingFrequencyNumerator,
		                int samplingFrequencyDenominator);
};

/**
 * @brief The Steim2EncoderFactory class implements the
 * encoder factory interface and supports the creation of
 * Steim2 encoders.
 */
class Steim2EncoderFactory : public SteimEncoderFactory {
	public:
		Encoder* create(const std::string &networkCode,
		                const std::string &stationCode,
		                const std::string &locationCode,
		                const std::string &channelCode,
		                int dt,
		                int samplingFrequencyNumerator,
		                int samplingFrequencyDenominator);
};

}
}

#endif