/*
 * Copyright (c) 2019-2020. Developed by Hedgecode.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.hedgecode.chess.scanner.portal;

import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.hedgecode.chess.scanner.ChessHogScannerException;
import org.hedgecode.chess.scanner.entity.PGNGame;
import org.hedgecode.chess.scanner.entity.PGNTournament;

/**
 * LiChessScanner
 *
 * @author Dmitry Samoshin aka gotty
 */
public class LiChessScanner extends AbstractSettingsScanner {

    private static final String SETTINGS_FILENAME = "lichess.settings";

    private static final String TOURNAMENT_GAMES_SPLIT_REGEX = "\\[Event \"[^\"]+\"\\]";
    private static final String TOURNAMENT_NAME_REGEX = "\\[Event \"([^\"]+)\"\\]";
    private static final String GAME_ID_REGEX = "\\[Site \"https://lichess.org/([^\"]+)\"\\]";

    @Override
    protected String getResourceName() {
        return SETTINGS_FILENAME;
    }

    @Override
    public PGNTournament getTournament(String tournamentId) throws ChessHogScannerException {
        PGNTournament tournament = new PGNTournament(tournamentId);
        assignTournamentGames(tournament);
        return tournament;
    }

    @Override
    public PGNTournament findTournament(String tournamentName) throws ChessHogScannerException {
        throw new ChessHogScannerException(
                "Lichess does not support searching for a tournament by name!"
        );
    }

    @Override
    public PGNGame getGame(String gameId) throws ChessHogScannerException {
        String pgn = request(
                assignUrl(gameId)
        );
        return new PGNGame(
                gameId, pgn
        );
    }

    private void assignTournamentGames(PGNTournament tournament) throws ChessHogScannerException {
        tournament.clearGames();
        List<String> pgnGames = split(
                assignUrl(
                        tournament.id(),
                        null
                ),
                TOURNAMENT_GAMES_SPLIT_REGEX
        );

        if (!pgnGames.isEmpty()) {
            tournament.setName(
                    find(TOURNAMENT_NAME_REGEX, pgnGames.get(0))
            );
        }

        for (String pgn : pgnGames) {
            String gameId = find(GAME_ID_REGEX, pgn);
            tournament.addGame(
                    new PGNGame(gameId, pgn)
            );
        }
    }

    private String find(String regex, String pgn) {
        Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE);
        Matcher matcher = pattern.matcher(pgn);
        if (matcher.find()) {
            return matcher.group(1);
        }
        return null;
    }

}