FileInstall.java

/*
 * SK's Minecraft Launcher
 * Copyright (C) 2010-2014 Albert Pham <http://www.sk89q.com> and contributors
 * Please see LICENSE.txt for license information.
 */

package com.skcraft.launcher.model.modpack;

import com.fasterxml.jackson.annotation.JsonIgnore;
import com.google.common.hash.HashFunction;
import com.google.common.hash.Hashing;
import com.google.common.io.Files;
import com.skcraft.launcher.install.InstallLog;
import com.skcraft.launcher.install.InstallLogFileMover;
import com.skcraft.launcher.install.Installer;
import com.skcraft.launcher.install.UpdateCache;
import lombok.Data;
import lombok.EqualsAndHashCode;
import lombok.NonNull;
import org.apache.commons.io.FilenameUtils;

import java.io.File;
import java.io.IOException;
import java.net.URL;

import static com.google.common.base.Preconditions.checkNotNull;
import static com.skcraft.launcher.LauncherUtils.concat;

@Data
@EqualsAndHashCode(callSuper = false)
public class FileInstall extends ManifestEntry {

    private static HashFunction hf = Hashing.sha1();
    private String version;
    private String hash;
    private String location;
    private String to;
    private long size;
    private boolean userFile;

    @JsonIgnore
    public String getImpliedVersion() {
        return checkNotNull(version != null ? version : hash);
    }

    @JsonIgnore
    public String getTargetPath() {
        return checkNotNull(this.to != null ? this.to : location);
    }

    @Override
    public void install(@NonNull Installer installer, @NonNull InstallLog log,
                        @NonNull UpdateCache cache, @NonNull File contentDir) throws IOException {
        if (getWhen() != null && !getWhen().matches()) {
            return;
        }

        String targetPath = getTargetPath();
        File targetFile = new File(contentDir, targetPath);
        String fileVersion = getImpliedVersion();
        URL url = concat(getManifest().getObjectsUrl(), getLocation());

        if (shouldUpdate(cache, targetFile)) {
            long size = this.size;
            if (size <= 0) {
                size = 10 * 1024;
            }

            File tempFile = installer.getDownloader().download(url, fileVersion, size, to);
            installer.queue(new InstallLogFileMover(log, tempFile, targetFile));
        } else {
            log.add(to, to);
        }
    }

    private boolean shouldUpdate(UpdateCache cache, File targetFile) throws IOException {
        if (targetFile.exists() && isUserFile()) {
            return false;
        }

        if (!targetFile.exists()) {
            return true;
        }

        if (hash != null) {
            String existingHash = Files.hash(targetFile, hf).toString();
            if (existingHash.equalsIgnoreCase(hash)) {
                return false;
            }
        }

        return cache.mark(FilenameUtils.normalize(getTargetPath()), getImpliedVersion());
    }

}