package net.knarcraft.minecraftserverlauncher.utility;

import net.knarcraft.minecraftserverlauncher.server.ServerTypeHandler;
import net.knarcraft.minecraftserverlauncher.server.servertypes.ServerType;
import net.knarcraft.minecraftserverlauncher.userinterface.GUI;

import javax.naming.ConfigurationException;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;

/**
 * This class handles all downloading of .jar files
 */
public final class JarDownloader {

    private final String jarDirectory;
    private final GUI gui;

    /**
     * Initializes a jar downloader
     *
     * @param gui          <p>The GUI to use for displaying messages</p>
     * @param jarDirectory <p>The directory to download jar files to</p>
     */
    public JarDownloader(GUI gui, String jarDirectory) {
        this.gui = gui;
        this.jarDirectory = jarDirectory;
    }

    /**
     * Downloads all jars to the program directory.
     *
     * @throws IOException On version file failure or folder creation failure
     */
    public void downloadJars() throws IOException {
        if (!new File(jarDirectory).exists() && !new File(jarDirectory).mkdirs()) {
            gui.showError("Could not create the Jars folder. Please run the program with admin permissions, or move it to " +
                    "a writable directory.");
            throw new FileNotFoundException("Unable to create jars folder");
        }
        try {
            gui.setStatus("Downloading all jars...");
            downloadAll();
            gui.setStatus("Finished downloading jars");
        } catch (FileNotFoundException | ConfigurationException e) {
            gui.setStatus(e.getMessage());
            throw new FileNotFoundException("One or more downloads failed: " + e.getMessage());
        }
    }

    /**
     * Downloads jar files for all possible server versions
     *
     * @throws IOException <p>If a jar fails to download</p>
     */
    private void downloadAll() throws IOException, ConfigurationException {
        for (ServerType type : ServerTypeHandler.getServerTypes()) {
            if (type.getName().equals("Custom")) {
                continue;
            }
            for (String version : type.getVersions()) {
                gui.setStatus("Downloading " + type.getName() + version + "...");
                boolean success = type.downloadJar(jarDirectory, version);
                if (!success) {
                    throw new FileNotFoundException("Unable to download the jar file for " + type.getName() + version);
                }
            }
        }
    }
}