/**

 * Relational pipes

 * Copyright © 2020 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, version 3 of the License.

 *

 * 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/>.

 */

#include <cstdlib>

#include <vector>

#include <sstream>

#include <memory>

#include <relpipe/writer/RelationalWriter.h>

#include <relpipe/writer/RelpipeWriterException.h>

#include <relpipe/writer/AttributeMetadata.h>

#include <relpipe/common/type/typedefs.h>

#include <relpipe/cli/CLI.h>

#include "INICommand.h"

#include "lib/uri.h"

#include "lib/INIReader.h"

#include "lib/BasicUnescapingProcessor.h"

#include "lib/BackspaceUnescapingProcessor.h"

#include "lib/JavaPropertiesUnescapingProcessor.h"

#include "lib/JavaPropertiesDialect.h"

using namespace std;

using namespace relpipe::writer;

using namespace relpipe::in::ini::lib;

namespace relpipe {

namespace in {

namespace ini {

class FlatINIContentHandler : public INIContentHandler {

private:

	wstring_convert < codecvt_utf8<wchar_t>> convertor; // INI parser works with UTF-8

	std::shared_ptr<writer::RelationalWriter> writer;

	Configuration& configuration;

	std::vector<std::string> currentSection;

	bool inDocument = false;

	std::string getCurrentSectionFullName() {

		std::stringstream result;

		// TODO: configurable hierarchy delimiter

		// TODO: escape delimiter characters that are part of the section names

		// TODO: hierarchical sections should be returned as an array/sequence when such data type is supported in the Relational pipes format and API

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

			if (i > 0)result << "/";

			result << currentSection[i];

		}

		return result.str();

	}

	class Record {

	public:

		relpipe::common::type::Integer lineNumber = -1;

		relpipe::common::type::Integer eventNumber = -1;

		std::string key;

		std::string subKey;

		std::string value;

		std::string comment;

		std::string whitespace;

		Record(const Event * const event) : lineNumber(event->lineNumber), eventNumber(event->eventNumber) {

		}

	};

	void write(const Record& record) {

		if (configuration.enableLineNumbers) writer->writeAttribute(&record.lineNumber, typeid (record.lineNumber));

		if (configuration.enableEventNumbers) writer->writeAttribute(&record.eventNumber, typeid (record.eventNumber));

		std::string section = getCurrentSectionFullName();

		std::string key = record.key;

		if (configuration.enableSections) writer->writeAttribute(convertor.from_bytes(section));

		else if (section.size()) key = section + "/" + record.key;

		writer->writeAttribute(convertor.from_bytes(key));

		if (configuration.enableSubKeys) writer->writeAttribute(convertor.from_bytes(record.subKey));

		writer->writeAttribute(convertor.from_bytes(record.value));

		if (configuration.enableComments) writer->writeAttribute(convertor.from_bytes(record.comment));

		if (configuration.enableWhitespace) writer->writeAttribute(convertor.from_bytes(record.whitespace));

	}

public:

	FlatINIContentHandler(std::shared_ptr<writer::RelationalWriter> writer, Configuration& configuration) : writer(writer), configuration(configuration) {

	}

	virtual ~FlatINIContentHandler() {

	}

	void startDocument() override {

		if (inDocument) throw std::out_of_range("Lunatic INI parser tried to start a document without ending the previous one.");

		inDocument = true;

		vector<AttributeMetadata> metadata;

		if (configuration.enableLineNumbers) metadata.push_back({L"line", TypeId::INTEGER});

		if (configuration.enableEventNumbers) metadata.push_back({L"event", TypeId::INTEGER});

		if (configuration.enableSections) metadata.push_back({L"section", TypeId::STRING});

		metadata.push_back({L"key", TypeId::STRING});

		if (configuration.enableSubKeys) metadata.push_back({L"sub_key", TypeId::STRING});

		metadata.push_back({L"value", TypeId::STRING});

		if (configuration.enableComments) metadata.push_back({L"comment", TypeId::STRING});

		if (configuration.enableWhitespace) metadata.push_back({L"whitespace", TypeId::STRING});

		writer->startRelation(configuration.relation, metadata, true);

	};

	void endDocument() override {

		if (!inDocument) throw std::out_of_range("Lunatic INI parser tried to end a document without starting it before.");

		inDocument = false;

		currentSection.clear();

	};

	void startSection(const SectionStartEvent& event) override {

		if (!inDocument) throw std::out_of_range("Lunatic INI parser tried to start a section without starting a document.");

		currentSection.push_back(event.name);

		if (configuration.enableComments && event.comment.size()) {

			Record record(&event);

			record.comment = event.comment;

			write(record);

		}

	};

	void endSection() override {

		if (currentSection.empty()) throw std::out_of_range("Lunatic INI parser tried to end a section without starting it before.");

		currentSection.pop_back();

	};

	void entry(const EntryEvent& event) override {

		if (!inDocument) throw std::out_of_range("Lunatic INI parser tried to emit an entry without starting a document.");

		Record record(&event);

		record.comment = event.comment;

		record.key = configuration.enableSubKeys ? event.key : event.fullKey;

		record.subKey = event.subKey;

		record.value = event.value;

		write(record);

	};

	void comment(const CommentEvent& event) override {

		if (!inDocument) throw std::out_of_range("Lunatic INI parser tried to emit a comment without starting a document.");

		if (configuration.enableComments) {

			Record record(&event);

			record.comment = event.comment;

			write(record);

		}

	}

	void whitespace(const WhitespaceEvent& event) override {

		if (!inDocument) throw std::out_of_range("Lunatic INI parser tried to emit a whitespace without starting a document.");

		if (configuration.enableWhitespace) {

			Record record(&event);

			record.whitespace = event.whitespace;

			write(record);

		}

	}

};

void INICommand::process(std::istream& input, std::shared_ptr<writer::RelationalWriter> writer, Configuration& configuration) {

	FlatINIContentHandler handler(writer, configuration);

	std::shared_ptr<INIReader> reader(INIReader::create(input));

	reader->addUnescapingProcessor(std::make_shared<BasicUnescapingProcessor>(), unescaping::Basic, true);

	reader->addUnescapingProcessor(std::make_shared<JavaPropertiesUnescapingProcessor>(), unescaping::JavaProperties, false);

	reader->addUnescapingProcessor(std::make_shared<BackspaceUnescapingProcessor>(), unescaping::Backspace, true);

	reader->addDialect(std::make_shared<JavaPropertiesDialect>(), dialect::JavaProperties, false);

	reader->addHandler(&handler);

	// TODO: smart pointers vs. references: are we going to call addUnescapingProcessor() dynamically/conditionally or share instances? Then pointers will be better.

	for (ParserOptionRecipe option : configuration.parserOptions) reader->setOption(convertor.to_bytes(option.uri), convertor.to_bytes(option.value));

	reader->process();

}

}

}

}