package launchserver.command.hash;

import java.io.IOException;
import java.net.URL;
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Collections;
import java.util.zip.ZipEntry;
import java.util.zip.ZipInputStream;

import launcher.client.ClientProfile.Version;
import launcher.helper.IOHelper;
import launcher.helper.LogHelper;
import launchserver.LaunchServer;
import launchserver.command.Command;

public final class DownloadAssetCommand extends Command {
    private static final String ASSET_URL_MASK = "http://launcher.sashok724.net/download/assets/%s.zip";

    public DownloadAssetCommand(LaunchServer server) {
        super(server);
    }

    @Override
    public String getArgsDescription() {
        return "<version> <dir>";
    }

    @Override
    public String getUsageDescription() {
        return "Download asset dir";
    }

    @Override
    public void invoke(String... args) throws Throwable {
        verifyArgs(args, 2);
        Version version = Version.byName(args[0]);
        String dirName = IOHelper.verifyFileName(args[1]);
        Path assetDir = server.updatesDir.resolve(dirName);

        // Create asset dir
        LogHelper.subInfo("Creating asset dir: '%s'", dirName);
        Files.createDirectory(assetDir);

        // Download required asset
        LogHelper.subInfo("Downloading asset, it may take some time");
        unpack(new URL(String.format(ASSET_URL_MASK, IOHelper.urlEncode(version.name))), assetDir);

        // Finished
        server.syncUpdatesDir(Collections.singleton(dirName));
        LogHelper.subInfo("Asset successfully downloaded: '%s'", dirName);
    }

    public static void unpack(URL url, Path dir) throws IOException {
        try (ZipInputStream input = IOHelper.newZipInput(url)) {
            for (ZipEntry entry = input.getNextEntry(); entry != null; entry = input.getNextEntry()) {
                if (entry.isDirectory()) {
                    continue; // Skip directories
                }

                // Unpack entry
                String name = entry.getName();
                LogHelper.subInfo("Downloading file: '%s'", name);
                IOHelper.transfer(input, dir.resolve(IOHelper.toPath(name)));
            }
        }
    }
}