#pragma once

#include <string>
#include <sstream>
#include <iostream>
#include <vector>
#include <locale>
#include <codecvt>

#include "../include/typedefs.h"
#include "../include/DataTypeReader.h"
#include "../include/DataTypeReader.h"
#include "format.h"

namespace relpipe {
namespace 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>(DATA_TYPE_ID_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;
	}

};

}
}