/**

 * 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/>.

 */

#pragma once

#include <vector>

#include <iostream>

#include <relpipe/writer/typedefs.h>

#include <relpipe/cli/CLI.h>

#include <relpipe/cli/RelpipeCLIException.h>

#include "Configuration.h"

namespace relpipe {

namespace in {

namespace cli {

class CLIParser {

private:

	relpipe::writer::string_t readNext(const std::vector<relpipe::writer::string_t>& arguments, int& i) {

		if (i < arguments.size()) return arguments[i++];

		else throw relpipe::cli::RelpipeCLIException(L"Missing CLI argument" + (i > 0 ? (L" after " + arguments[i - 1]) : L""), relpipe::cli::CLI::EXIT_CODE_BAD_CLI_ARGUMENTS);

	}

	void readNextRecord(const std::vector<relpipe::writer::string_t>& arguments, int& i, RelationConfiguration& currentRelation) {

		for (const auto& a : currentRelation.attributes) currentRelation.values.emplace_back(readNext(arguments, i));

	}

	void addRelation(Configuration& c, RelationConfiguration& currentRelation) {

		if (currentRelation.relation.size()) {

			c.relationConfigurations.push_back(currentRelation);

			currentRelation = RelationConfiguration();

		}

	}

	/**

	 * TODO: use a common method

	 */

	bool parseBoolean(const relpipe::writer::string_t& value) {

		if (value == L"true") return true;

		else if (value == L"false") return false;

		else throw relpipe::cli::RelpipeCLIException(L"Unable to parse boolean value: " + value + L" (expecting true or false)", relpipe::cli::CLI::EXIT_CODE_BAD_CLI_ARGUMENTS);

	}

	/**

	 * TODO: use a common method

	 */

	relpipe::writer::TypeId parseTypeId(const relpipe::writer::string_t& value) {

		using t = relpipe::writer::TypeId;

		if (value == L"string") return t::STRING;

		else if (value == L"integer") return t::INTEGER;

		else if (value == L"boolean") return t::BOOLEAN;

		else throw relpipe::cli::RelpipeCLIException(L"Unable to parse TypeId: " + value, relpipe::cli::CLI::EXIT_CODE_BAD_CLI_ARGUMENTS);

	}

public:

	static const relpipe::writer::string_t OPTION_RELATION;

	static const relpipe::writer::string_t OPTION_WRITE_HEADER;

	static const relpipe::writer::string_t OPTION_ATTRIBUTE;

	static const relpipe::writer::string_t OPTION_RECORD;

	static const relpipe::writer::string_t OPTION_RECORDS;

	static const relpipe::writer::string_t OPTION_RECORDS_STDIN;

	Configuration parse(const std::vector<relpipe::writer::string_t>& arguments) {

		Configuration c;

		RelationConfiguration currentRelation;

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

			relpipe::writer::string_t option = readNext(arguments, i);

			if (option == OPTION_RELATION) {

				addRelation(c, currentRelation); // previous relation

				currentRelation.relation = readNext(arguments, i);

			} else if (option == OPTION_WRITE_HEADER) {

				currentRelation.writeHeader = parseBoolean(readNext(arguments, i));

			} else if (option == OPTION_ATTRIBUTE) {

				AttributeRecipe attribute;

				attribute.name = readNext(arguments, i);

				attribute.type = parseTypeId(readNext(arguments, i));

				currentRelation.attributes.push_back(attribute);

			} else if (option == OPTION_RECORD) {

				readNextRecord(arguments, i, currentRelation);

			} else if (option == OPTION_RECORDS) {

				while (i < arguments.size()) readNextRecord(arguments, i, currentRelation);

			} else if (option == OPTION_RECORDS_STDIN) {

				if (parseBoolean(readNext(arguments, i))) {

					for (RelationConfiguration r : c.relationConfigurations) if (r.valueStream) throw relpipe::cli::RelpipeCLIException(L"Only one relation can read data from STDIN.", relpipe::cli::CLI::EXIT_CODE_BAD_CLI_ARGUMENTS);

					currentRelation.valueStream = &std::cin;

				}

			} else throw relpipe::cli::RelpipeCLIException(L"Unsupported CLI option: " + option, relpipe::cli::CLI::EXIT_CODE_BAD_CLI_ARGUMENTS);

		}

		addRelation(c, currentRelation); // last relation

		return c;

	}

	virtual ~CLIParser() {

	}

};

const relpipe::writer::string_t CLIParser::OPTION_RELATION = L"--relation";

const relpipe::writer::string_t CLIParser::OPTION_WRITE_HEADER = L"--write-header";

const relpipe::writer::string_t CLIParser::OPTION_ATTRIBUTE = L"--attribute";

const relpipe::writer::string_t CLIParser::OPTION_RECORD = L"--record";

const relpipe::writer::string_t CLIParser::OPTION_RECORDS = L"--records";

const relpipe::writer::string_t CLIParser::OPTION_RECORDS_STDIN = L"--records-on-stdin";

}

}

}