package com.fr.plugin.external;

import com.fr.base.FRContext;
import com.fr.general.IOUtils;
import com.fr.general.xml.GeneralXMLTools;
import com.fr.stable.CoreGraphHelper;
import com.fr.stable.StableUtils;
import com.fr.stable.StringUtils;
import com.fr.stable.project.ProjectConstants;
import com.fr.workspace.WorkContext;

import java.awt.Image;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class ImageManager {

    private static ImageManager manager;
    private static Image EMPTY = CoreGraphHelper.createBufferedImage(0, 0);

    public static ImageManager getInstance() {
        if (manager == null) {
            manager = new ImageManager();
        }

        return manager;
    }

    private Map<String, ImageBean> cachedMap = new ConcurrentHashMap<String, ImageBean>();
    private ExecutorService executorService = Executors.newSingleThreadExecutor();
    private boolean compress = true;

    public void release() {
        cachedMap.clear();
        executorService.shutdown();
    }

    public void updateImage(ExternalImageBackground background) {
        updateImage(background.getId(), background.getImage());
    }

    public void updateImage(String id, Image image) {
        updateImage(id, image, true);
    }

    public void updateImage(String id, Image image, boolean save) {
        if (StringUtils.isNotEmpty(id) && image != null) {
            cachedMap.put(id, new ImageBean(image));
            if (save) {
                saveImageToFile(image, id);
            }
        }
    }

    public void removeImage(String id) {
        cachedMap.remove(id);
    }

    public String[] listAllIds() {
        updateImageFromDisk();
        return cachedMap.keySet().toArray(new String[cachedMap.size()]);
    }

    public Image findImageById(String id) {
        ImageBean result = cachedMap.get(id);
        if (result == null) {
            updateImageFromDisk(id);
            result = cachedMap.get(id);
            if (result == null) {
                return EMPTY;
            }
        }

        return result.getImage();
    }

    public String findAttachId(String id) {
        ImageBean result = cachedMap.get(id);
        if (result == null) {
            updateImageFromDisk(id);
            result = cachedMap.get(id);
            if (result == null) {
                return StringUtils.EMPTY;
            }
        }

        return result.getAttachment().getID();
    }

    public boolean isCompress() {
        return compress;
    }

    public void setCompress(boolean compress) {
        this.compress = compress;
    }

    public void updateImageFromDisk() {
        String path = StableUtils.pathJoin(WorkContext.getCurrent().getPath(),
                ProjectConstants.ASSETS_NAME, "background");
        File imageFolder = new File(path);
        if (!imageFolder.exists()) {
            return;
        }

        File[] images = imageFolder.listFiles();
        for (File imageFile : images) {
            String name = imageFile.getName();
            String id = name.substring(0, name.lastIndexOf("."));
            if(cachedMap.containsKey(id)) {
                continue;
            }

            try {
                byte[] content = IOUtils.inputStream2Bytes(new FileInputStream(imageFile));
                Image image =  GeneralXMLTools.imageDecode(content);
                updateImage(id, image, false);
            } catch (Throwable e) {
                FRContext.getLogger().debug("Image read failed: " + e.getMessage() + " id: " + id);
            }
        }
    }
    public void updateImageFromDisk(String targetId) {
        String path = StableUtils.pathJoin(WorkContext.getCurrent().getPath(),
                ProjectConstants.ASSETS_NAME, "background");
        File imageFolder = new File(path);
        if (!imageFolder.exists()) {
            return;
        }

        File[] images = imageFolder.listFiles();
        for (File imageFile : images) {
            String name = imageFile.getName();
            int dotIndex = name.lastIndexOf(".");
            if (dotIndex <= 0) {
                continue;
            }
            String id = name.substring(0, dotIndex);
            if(cachedMap.containsKey(id) || !targetId.equals(id)) {
                continue;
            }

            try {
                byte[] content = IOUtils.inputStream2Bytes(new FileInputStream(imageFile));
                Image image =  GeneralXMLTools.imageDecode(content);
                updateImage(id, image, false);
            } catch (Throwable e) {
                FRContext.getLogger().debug("Image read failed: " + e.getMessage() + " id: " + id);
            }
        }
    }

    private void cacheAllImage() {
        executorService.execute(new Runnable() {
            @Override
            public void run() {
                if(!(WorkContext.getCurrent().isLocal())) {
                    FRContext.getLogger().error("图片外置不支持远程设计!");
                    return;
                }

                String path = StableUtils.pathJoin(WorkContext.getCurrent().getPath(),
                        ProjectConstants.ASSETS_NAME, "background");
                File imageFolder = new File(path);
                if (!imageFolder.exists()) {
                    return;
                }

                File[] images = imageFolder.listFiles();
                for (File imageFile : images) {
                    String name = imageFile.getName();
                    String id = name.substring(0, name.lastIndexOf("."));
                    try {
                        byte[] content = IOUtils.inputStream2Bytes(new FileInputStream(imageFile));
                        Image image =  GeneralXMLTools.imageDecode(content);
                        updateImage(id, image, false);
                    } catch (Throwable e) {
                        FRContext.getLogger().debug("Image read failed: " + e.getMessage() + " id: " + id);
                    }
                }
            }
        });
    }

    private void saveImageToFile(final Image image, final String id) {
        executorService.execute(new Runnable() {
            @Override
            public void run() {
                // 存到磁盘
                String path = StableUtils.pathJoin(WorkContext.getCurrent().getPath(),
                        ProjectConstants.ASSETS_NAME, "background", id + ".png");
                File imageFile = new File(path);
                try {
                    StableUtils.makesureFileExist(imageFile);
                    FileOutputStream out = new FileOutputStream(imageFile);
                    IOUtils.writeImage(image, "png", out);
                    out.close();
                } catch (IOException e) {
                    FRContext.getLogger().error(e.getMessage());
                }
            }
        });
    }

}