/*
 * Copyright (c) 2018-2019. 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.img.piece;

import java.io.File;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

import javax.imageio.ImageIO;

import org.hedgecode.chess.img.AbstractImageLoader;
import org.hedgecode.chess.img.ImageConstants;
import org.hedgecode.chess.img.ImageException;
import org.hedgecode.chess.img.ImageFilter;

/**
 *
 *
 * @author Dmitry Samoshin aka gotty
 */
public class PieceSetLoader extends AbstractImageLoader {

    private static final File PIECES_PATH = new File(IMAGES_PATH, ImageConstants.RESOURCE_PIECES_DIR);

    private static final String[] PIECES_NAMES = PieceSet.getAllPieceNames();

    private Map<String, PieceSet> pieceSetMap = new HashMap<>();

    @Override
    public PieceSet load(String name) throws ImageException {
        PieceSet pieceSet = null;
        if (Type.STATELESS.equals(loadType()) || !pieceSetMap.containsKey(name)) {
            File piecePath = new File(PIECES_PATH, name);
            if (piecePath.exists() && piecePath.isDirectory()) {
                pieceSet = loadPieces(piecePath);
            }
            if (Type.STATEFUL.equals(loadType()) && pieceSet != null) {
                pieceSetMap.put(name, pieceSet);
            }
        } else {
            pieceSet = pieceSetMap.get(name);
        }
        return pieceSet;
    }

    @Override
    public void unload(String name) {
        if (Type.STATEFUL.equals(loadType()) && pieceSetMap.containsKey(name)) {
            pieceSetMap.remove(name);
        }
    }

    @Override
    protected void clear() {
        pieceSetMap.clear();
    }

    private PieceSet loadPieces(File piecePath) throws ImageException {
        PieceSet pieceSet = PieceSet.create();
        File[] images = piecePath.listFiles(new ImageFilter(PIECES_NAMES));
        if (images != null) {
            for (File image : images) {
                if (image.isFile()) {
                    String filename = image.getName();
                    try {
                        pieceSet.add(
                                filename.substring(0, filename.lastIndexOf('.')),
                                ImageIO.read(image)
                        );
                    } catch (IOException e) {
                        throw new ImageException(e.getMessage()); // todo: locale
                    }
                }
            }
        }
        return pieceSet.isFull() ? pieceSet : null;
    }

}