package com.yahoo.labs.samoa.utils;

/*
 * #%L
 * SAMOA
 * %%
 * Copyright (C) 2014 - 2015 Apache Software Foundation
 * %%
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 * #L%
 */

import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.jar.Attributes;
import java.util.jar.JarOutputStream;
import java.util.jar.Manifest;
import java.util.zip.ZipEntry;

/**
 * Utils class for building and deploying applications programmatically.
 * 
 * @author severien
 * 
 */
public class Utils {

  public static void buildSamoaPackage() {
    try {
      String output = "/tmp/samoa/samoa.jar";// System.getProperty("user.home") + "/samoa.jar";
      Manifest manifest = createManifest();

      BufferedOutputStream bo;

      bo = new BufferedOutputStream(new FileOutputStream(output));
      JarOutputStream jo = new JarOutputStream(bo, manifest);

      String baseDir = System.getProperty("user.dir");
      System.out.println(baseDir);

      File samoaJar = new File(baseDir + "/target/samoa-0.0.1-SNAPSHOT.jar");
      addEntry(jo, samoaJar, baseDir + "/target/", "/app/");
      addLibraries(jo);

      jo.close();
      bo.close();
    } catch (IOException e) {
      e.printStackTrace();
    }

  }

  // TODO should get the modules file from the parameters
  public static void buildModulesPackage(List<String> modulesNames) {
    System.out.println(System.getProperty("user.dir"));
    try {
      String baseDir = System.getProperty("user.dir");
      List<File> filesArray = new ArrayList<>();
      for (String module : modulesNames) {
        module = "/" + module.replace(".", "/") + ".class";
        filesArray.add(new File(baseDir + module));
      }
      String output = System.getProperty("user.home") + "/modules.jar";

      Manifest manifest = new Manifest();
      manifest.getMainAttributes().put(Attributes.Name.MANIFEST_VERSION,
          "1.0");
      manifest.getMainAttributes().put(Attributes.Name.IMPLEMENTATION_URL,
          "http://samoa.yahoo.com");
      manifest.getMainAttributes().put(
          Attributes.Name.IMPLEMENTATION_VERSION, "0.1");
      manifest.getMainAttributes().put(Attributes.Name.IMPLEMENTATION_VENDOR,
          "Yahoo");
      manifest.getMainAttributes().put(
          Attributes.Name.IMPLEMENTATION_VENDOR_ID, "SAMOA");

      BufferedOutputStream bo;

      bo = new BufferedOutputStream(new FileOutputStream(output));
      JarOutputStream jo = new JarOutputStream(bo, manifest);

      File[] files = filesArray.toArray(new File[filesArray.size()]);
      addEntries(jo, files, baseDir, "");

      jo.close();
      bo.close();
    } catch (IOException e) {
      e.printStackTrace();
    }

  }

  private static void addLibraries(JarOutputStream jo) {
    try {
      String baseDir = System.getProperty("user.dir");
      String libDir = baseDir + "/target/lib";
      File inputFile = new File(libDir);

      File[] files = inputFile.listFiles();
      for (File file : files) {
        addEntry(jo, file, baseDir, "lib");
      }
      jo.close();

    } catch (IOException e) {
      e.printStackTrace();
    }
  }

  private static void addEntries(JarOutputStream jo, File[] files, String baseDir, String rootDir) {
    for (File file : files) {

      if (!file.isDirectory()) {
        addEntry(jo, file, baseDir, rootDir);
      } else {
        File dir = new File(file.getAbsolutePath());
        addEntries(jo, dir.listFiles(), baseDir, rootDir);
      }
    }
  }

  private static void addEntry(JarOutputStream jo, File file, String baseDir, String rootDir) {
    try {
      BufferedInputStream bi = new BufferedInputStream(new FileInputStream(file));

      String path = file.getAbsolutePath().replaceFirst(baseDir, rootDir);
      jo.putNextEntry(new ZipEntry(path));

      byte[] buf = new byte[1024];
      int anz;
      while ((anz = bi.read(buf)) != -1) {
        jo.write(buf, 0, anz);
      }
      bi.close();
    } catch (IOException e) {
      e.printStackTrace();
    }
  }

  public static Manifest createManifest() {
    Manifest manifest = new Manifest();
    manifest.getMainAttributes().put(Attributes.Name.MANIFEST_VERSION, "1.0");
    manifest.getMainAttributes().put(Attributes.Name.IMPLEMENTATION_URL, "http://samoa.yahoo.com");
    manifest.getMainAttributes().put(Attributes.Name.IMPLEMENTATION_VERSION, "0.1");
    manifest.getMainAttributes().put(Attributes.Name.IMPLEMENTATION_VENDOR, "Yahoo");
    manifest.getMainAttributes().put(Attributes.Name.IMPLEMENTATION_VENDOR_ID, "SAMOA");
    Attributes s4Attributes = new Attributes();
    s4Attributes.putValue("S4-App-Class", "path.to.Class");
    Attributes.Name name = new Attributes.Name("S4-App-Class");
    Attributes.Name S4Version = new Attributes.Name("S4-Version");
    manifest.getMainAttributes().put(name, "samoa.topology.impl.DoTaskApp");
    manifest.getMainAttributes().put(S4Version, "0.6.0-incubating");
    return manifest;
  }

  public static Object getInstance(String className) {
    Class<?> cls;
    Object obj = null;
    try {
      cls = Class.forName(className);
      obj = cls.newInstance();
    } catch (ClassNotFoundException | InstantiationException | IllegalAccessException e) {
      e.printStackTrace();
    }
    return obj;
  }
}