/*
 * Copyright 2004 - 2008 Christian Sprajc. All rights reserved.
 *
 * This file is part of PowerFolder.
 *
 * PowerFolder 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.
 *
 * PowerFolder 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 PowerFolder. If not, see <http://www.gnu.org/licenses/>.
 *
 * $Id$
 */
package de.dal33t.powerfolder.disk;

import java.io.File;

import de.dal33t.powerfolder.Controller;
import de.dal33t.powerfolder.light.FolderInfo;
import de.dal33t.powerfolder.util.Reject;

/**
 * Utility class with methods for creating and converting preview folders.
 */
public class FolderPreviewHelper {

    /**
     * The System property name for the tmp dir
     */
    private static final String JAVA_IO_TMPDIR = "java.io.tmpdir";

    /**
     * The powerfolder directory that preview folders are put in.
     */
    private static final String DOT_POWER_FOLDER = ".Preview";

    /**
     * This helper creates FolderSettings for creation of a preview folder. The
     * local base dir is in the system temp dir and there is no synchronization
     * for a preview folder.
     * 
     * @param folderName
     * @return the settings for previewing the folder.
     */
    public static FolderSettings createPreviewFolderSettings(String folderName)
    {
        File localBase = makePreviewBaseDir(folderName);
        return new FolderSettings(localBase, SyncProfile.NO_SYNC, false,
            true, null, 0, false);
    }

    // Creates a preview folder directory for a folderName.
    // The folder is put in [java.io.tempdir]/.PowerFolder/folderName/
    private static File makePreviewBaseDir(String folderName) {
        String javaTempDir = System.getProperty(JAVA_IO_TMPDIR);
        File tempPF = new File(javaTempDir, DOT_POWER_FOLDER);
        return new File(tempPF, folderName);
    }

    /**
     * Converts a normal folder to a preview folder.
     * 
     * @param controller
     * @param folder
     * @return if succeeded
     */
    public static boolean convertFolderToPreview(Controller controller,
        Folder folder)
    {

        Reject.ifTrue(folder.isPreviewOnly(),
            "Can not convert a preview folder to preview");

        FolderRepository folderRepository = controller.getFolderRepository();

        FolderSettings initialFolderSettings = FolderSettings.load(controller,
            folder.getConfigEntryId());

        if (initialFolderSettings == null) {
            return false;
        }

        FolderSettings previewFolderSettings = createPreviewFolderSettings(folder
            .getName());
        FolderInfo folderInfo = new FolderInfo(folder);

        // Saved FolderSettings are like initial, but preview is true.
        FolderSettings savedFolderSettings = new FolderSettings(
            initialFolderSettings.getLocalBaseDir(),
            initialFolderSettings.getSyncProfile(),
            false,
            true,
            initialFolderSettings.getDownloadScript(),
            initialFolderSettings.getVersions(),
            initialFolderSettings.isSyncPatterns());

        folderRepository.removeFolder(folder, false);
        folderRepository.createPreviewFolder(folderInfo, previewFolderSettings);
        folderRepository
            .saveFolderConfig(folderInfo, savedFolderSettings, true);

        return true;
    }

    /**
     * Converts a preview folder to a normal folder.
     * 
     * @param controller
     * @param folder
     * @param newFolderSettings
     * @param deleteSystemSubDir
     */
    public static void convertFolderFromPreview(Controller controller,
        Folder folder, FolderSettings newFolderSettings,
        boolean deleteSystemSubDir)
    {
        Reject.ifTrue(!folder.isPreviewOnly(),
            "Can not convert a non-preview folder to non-previrew");
        Reject.ifTrue(newFolderSettings.isPreviewOnly(),
            "Can not convert to a preview folder");

        FolderRepository folderRepository = controller.getFolderRepository();
        FolderInfo folderInfo = new FolderInfo(folder);
        folderRepository.removeFolder(folder, deleteSystemSubDir);
        Folder f = folderRepository.createFolder(folderInfo, newFolderSettings);
        f.addDefaultExcludes();
    }
}