/**

 * Relational pipes (library)

 * Copyright © 2018 František Kučera (Frantovo.cz, GlobalCode.info)

 *

 * This program is free software: you can redistribute it and/or modify

 * it under the terms of the:

 *  - GNU Lesser General Public License as published by the Free Software Foundation;

 *    either version 3 of the License, or (at your option) any later version;

 *    or (at your option)

 *  - GNU General Public License as published by the Free Software Foundation;

 *    either version 2 of the License, or (at your option) any later version.

 *

 * This program is distributed in the hope that it will be useful,

 * but WITHOUT ANY WARRANTY; without even the implied warranty of

 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

 * GNU General Public License for more details.

 *

 * You should have received a copy of the GNU General Public License

 * along with this program. If not, see <http://www.gnu.org/licenses/>.

 */

#pragma once

#include <string>

#include <sstream>

#include <iostream>

#include <vector>

#include <locale>

#include <codecvt>

#include <relpipe/protocol/constants.h>

#include "../../include/relpipe/reader/RelpipeReaderException.h"

#include "../../include/relpipe/reader/typedefs.h"

#include "../DataTypeReader.h"

namespace relpipe {

namespace reader {

namespace types {

using namespace relpipe::protocol;

using namespace relpipe::reader;

/**

 * The prototype does not recognize any encoding,

 * it just works with c++ strings in encoding default to given platform. 

 * In the real implementation of relational pipes, there will be DataTypes for particular encodings.

 */

class StringDataTypeReader : public DataTypeReader<string_t> {

private:

	IntegerDataTypeReader integerType;

	std::wstring_convert<std::codecvt_utf8<wchar_t>> convertor; // TODO: support also other encodings.

public:

	StringDataTypeReader() : DataTypeReader<string_t>(TypeId::STRING, DATA_TYPE_CODE_STRING) {

	}

	string_t readValue(std::istream &input) override {

		integer_t length = integerType.readValue(input);

		// TODO: check maximum length of single field

		// if (length > 4000) throw RelpipeException("data too long", EXIT_CODE_DATA_ERROR);

		std::vector<char> buf(length);

		input.read(buf.data(), length);

		if (input.good()) {

			return convertor.from_bytes(std::string(buf.data(), length));

		} else {

			throw RelpipeReaderException(L"Error while reading string from the stream.");

		}

	}

	string_t toString(const string_t &value) override {

		return value;

	}

};

}

}

}