/*
 *
 *   Copyright (c) 1999 - 2011 my-Channels Ltd
 *   Copyright (c) 2012 - 2017 Software AG, Darmstadt, Germany and/or Software AG USA Inc., Reston, VA, USA, and/or its subsidiaries and/or its affiliates and/or their licensors.
 *
 *   Use, reproduction, transfer, publication or disclosure is prohibited except as specifically provided for in your License Agreement with Software AG.
 *
 */
package com.pcbsys.nirvana.nAdminAPI.apps;

import com.pcbsys.nirvana.apps.nSampleApp;
import com.pcbsys.nirvana.client.nSessionAttributes;
import com.pcbsys.nirvana.nAdminAPI.nACL;
import com.pcbsys.nirvana.nAdminAPI.nContainer;
import com.pcbsys.nirvana.nAdminAPI.nRealmACLEntry;
import com.pcbsys.nirvana.nAdminAPI.nRealmNode;
import java.util.Enumeration;

/**
 * This application can be used to remove a subject from a realm
 * You can also specify to remove an acl entry from all known realms within a namespace, by
 * recursively searching through looking for other realm nodes and removing the acl entry
 * This is achieved by specifying -r as a command line parameter.
 */

public class nDelRealmAclEntry extends nSampleApp {

  /**
   * Private variables used in this application
   */
  private String realm = null;
  private String name = null;
  private String host = null;
  private boolean recursive = false;
  private nSessionAttributes attr = null;
  private nRealmNode node = null;

  /**
   * Construct and instance of this class using the command line arguments passed
   * when it is executed.
   */
  public nDelRealmAclEntry(String args[]) {
    try {
      // set the parameters required for this operation
      processArgs(args);
      System.out.println("Connecting to " + realm);
      // construct the session attributes from the realm
      attr = new nSessionAttributes(realm);
      // get the root realm node from the realm admin
      node = new nRealmNode(attr);
      if (!node.isAuthorised()) {
        System.out.println("User not authorised on this node " + realm);
        return;
      }

      // wait for the entire node namespace to be constructed if
      // the operation is recursive
      node.waitForEntireNameSpace();
      System.out.println("Removing entry for " + name + "@" + host);
      // remove the entry from the acl
      node.removeRealmACLEntry(new nRealmACLEntry(name + "@" + host));
      System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
      System.out.println("Removed ACL entry for " + node.getName());
      System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
      dump();
      // if you specify -r as a command line parameter, you can choose to traverse the entire
      // realm namespace, including any realms that have been added to the root realm node
      if (recursive) {
        traverse(node);
      }
      node.close();
    } catch (Exception e) {
      e.printStackTrace();
    }
  }

  /**
   * recursively search through the nodes from a realm node looking for other realm nodes
   */
  public nRealmNode traverse(nRealmNode p_node) {
    // get the enumeration of child nodes from p_node
    Enumeration enum1 = p_node.getNodes();
    while (enum1.hasMoreElements()) {
      Object obj = enum1.nextElement();
      // only deal with realm nodes
      if (obj instanceof nRealmNode) {
        nRealmNode node = (nRealmNode) obj;
        try {
          node.removeRealmACLEntry(new nRealmACLEntry(name + "@" + host));
        } catch (Exception e) {
          e.printStackTrace();
        }
        System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
        System.out.println("Removed ACL entry for " + node.getName());
        System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
        dump();
        // now traverse the child nodes
        return traverse(node);
      } else if (obj instanceof nContainer) {
        nContainer cont = (nContainer) obj;
        searchNode(cont.getNodes());
      }
    }
    return null;
  }

  /**
   * Search the enumeration of nodes passed as a parameter
   */
  private void searchNode(Enumeration p_nodes) {
    try {
      while (p_nodes.hasMoreElements()) {
        Object obj = p_nodes.nextElement();
        if (obj instanceof nRealmNode) {
          nRealmNode node = (nRealmNode) obj;
          try {
            // get the acl for this realm node
            nACL acl = node.getACLs();
            // remove the entry from the acl
            acl.remove(name + "@" + host);
            // set the node acl to the acl list with the removed entry
            node.setACLs(acl);
          } catch (Exception e) {
            e.printStackTrace();
          }
          System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
          System.out.println("Removed ACL entry for " + node.getName());
          System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
          dump();
        } else if (obj instanceof nContainer) {
          searchNode(((nContainer) obj).getNodes());
        }
      }
    } catch (Exception ex) {
      ex.printStackTrace();
    }
  }

  /**
   * If you construct an instance of this class from another class, you can set the name
   * and host for the subject to remove.
   */
  public void setSubject(String p_name, String p_host) {
    name = p_name;
    host = p_host;
  }

  /**
   * Output to system.out the permissions that have been set
   */
  public void dump() {
    System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
    System.out.println("NAME                   : " + name);
    System.out.println("HOST                   : " + host);
    System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
  }

  /**
   * Set the program variables and flags based on command line args
   */
  public void getOptions(String args[]) {
    realm = System.getProperty("RNAME", null);
    if (realm == null) {
      Usage();
      System.exit(1);
    }
    name = System.getProperty("NAME", null);
    if (name == null) {
      Usage();
      System.exit(1);
    }
    host = System.getProperty("HOST", null);
    if (host == null) {
      Usage();
      System.exit(1);
    }
    for (int i = 0; i < args.length; i++) {
      if (args[i].equalsIgnoreCase("-r")) {
        recursive = true;
      }
    }
  }

  protected void processArgs(String[] args) {
    if (args.length == 0) {
      Usage();
      System.exit(1);
    }
    switch (args.length) {
      case 1:
        if (args[0].equals("-?")) {
          UsageEnv();
        }
        System.setProperty("NAME", args[0]);
        getOptions(null);
        break;
      default:
        System.setProperty("NAME", args[0]);
        System.setProperty("HOST", args[1]);
        getOptions(args);
    }
  }

  /**
   * Run this as a command line program passing the command line args.
   * Or construct one of these classes from another class ensuring you have added :
   * RNAME
   * NAME
   * HOST
   * as system properties
   */
  public static void main(String[] args) {
    processEnvironmentVariables();

    nDelRealmAclEntry setAcl = new nDelRealmAclEntry(args);
    System.exit(0);
  }

  /**
   * Prints the usage message for this class
   */
  private static void Usage() {

    System.out.println("Usage ...\n");
    System.out.println("ndelrealmacl <user> <host> [-r] \n");
    System.out.println("<Required Arguments> \n");
    System.out.println("<user> - User name parameter to delete the realm ACL entry from");
    System.out.println("<host> - Host name parameter to delete the realm ACL entry from");
    System.out.println("\n[Optional Arguments] \n");
    System.out.println("[-r] - Specifies whether recursive traversal of the namespace should be done");
    System.out.println("\n\nNote: -? provides help on environment variables \n");
  }
}