/**

 * Relational pipes

 * 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 General Public License as published by

 * the Free Software Foundation, either version 3 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 <vector>

#include <iostream>

#include <sstream>

#include <locale>

#include <codecvt>

#include <regex>

#include <relpipe/reader/typedefs.h>

#include <relpipe/reader/TypeId.h>

#include <relpipe/reader/handlers/RelationalReaderStringHandler.h>

#include <relpipe/reader/handlers/AttributeMetadata.h>

#include <relpipe/xmlwriter/XMLWriter.h>

namespace relpipe {

namespace out {

namespace xml {

using namespace relpipe::reader;

using namespace relpipe::xmlwriter;

class XmlHandler : public handlers::RelationalReaderStringHadler {

private:

	const wstring XMLNS = L"tag:globalcode.info,2018:relpipe";

	shared_ptr<XMLWriter> xmlWriter;

	std::vector<TypeId> columnTypes;

	std::vector<string_t> columnTypeCodes;

	std::vector<string_t> columnNames;

	integer_t valueCount = 0;

	integer_t columnCount = 0;

	integer_t relationCount = 0;

public:

	XmlHandler(std::ostream& output) : xmlWriter(new XMLWriter(output)) {

	}

	void startRelation(string_t name, std::vector<handlers::AttributeMetadata> attributes) override {

		valueCount = 0;

		columnCount = 0;

		if (relationCount == 0) {

			xmlWriter->writeStartElement(L"relpipe",{L"xmlns", XMLNS});

		} else {

			xmlWriter->writeEndElement();

			xmlWriter->writeEndElement();

		}

		relationCount++;

		xmlWriter->writeStartElement(L"relation");

		xmlWriter->writeTextElement(L"name",{}, name);

		xmlWriter->writeStartElement(L"attributes-metadata");

		columnCount = attributes.size();

		columnTypes.resize(columnCount);

		columnTypeCodes.resize(columnCount);

		columnNames.resize(columnCount);

		for (int i = 0; i < attributes.size(); i++) {

			columnNames[i] = attributes[i].getAttributeName();

			columnTypes[i] = attributes[i].getTypeId();

			columnTypeCodes[i] = attributes[i].getTypeName();

			xmlWriter->writeEmptyElement(L"attribute-metadata",{

				L"name", columnNames[i],

				L"type", columnTypeCodes[i]

			});

		}

		xmlWriter->writeEndElement();

		// TODO: print attribute metadata

	}

	void attribute(const string_t& value) override {

		integer_t i = valueCount % columnCount;

		if (i == 0 && valueCount) xmlWriter->writeEndElement();

		if (i == 0) xmlWriter->writeStartElement(L"record");

		valueCount++;

		// TODO: print attribute metadata (only optional, not default)

		xmlWriter->writeTextElement(L"attribute",{

			L"name", columnNames[i],

			L"type", columnTypeCodes[i]

		}, value);

	}

	void endOfPipe() {

		if (valueCount) xmlWriter->writeEndElement();

		if (relationCount) xmlWriter->writeEndElement();

		xmlWriter->writeEndElement();

	}

};

}

}

}