/*
 *
 *   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.nChannelACLEntry;
import com.pcbsys.nirvana.nAdminAPI.nContainer;
import com.pcbsys.nirvana.nAdminAPI.nLeafNode;
import com.pcbsys.nirvana.nAdminAPI.nRealmNode;
import java.util.Enumeration;

/**
 * This application can be used to change permissions for a subject on a channel
 */

public class nChangeChanAclEntry extends nSampleApp {

  /**
   * Private variables used in this application
   */
  public static final String everyone = "everyone";
  public static final String everywhere = "everywhere";

  private String realm = null;
  private String name = null;
  private String host = null;
  private boolean pattern = false;
  private boolean factory = false;
  private boolean canListAcl = false;
  private boolean canModifyAcl = false;
  private boolean fullPrivileges = false;
  private boolean canGetLastEid = false;
  private boolean canRead = false;
  private boolean canWrite = false;
  private boolean canPurge = false;
  private boolean canNamed = false;
  private nSessionAttributes attr = null;
  private String channelName = null;
  private nRealmNode node = null;
  private nACL acl = null;
  private String changeArgs[] = null;

  /**
   * Construct an instance of this class using the command line arguments passed
   * when it is executed.
   */
  public nChangeChanAclEntry(String args[]) {
    try {
      changeArgs = args;
      // set the parameters required for this operation
      processArgs(changeArgs);
      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
      System.out.print("waiting for namepsace construction..... ");
      node.waitForEntireNameSpace();
      System.out.println("finished");
      // call the method to search from the root realm node
      searchNode(node);
      // close the realm node which will close all connections to child nodes
      node.close();
    } catch (Exception e) {
      e.printStackTrace();
    }
  }

  /**
   * set the permissions on the channel
   */
  public void setChannel(nLeafNode p_leaf) {
    try {
      // get the acl for the channel node
      acl = p_leaf.getACLs();
      System.out.println("Creating new entry for " + name + "@" + host);
      // create a new acl entry with the name and host
      nChannelACLEntry lookup = (nChannelACLEntry) acl.find(name + "@" + host);
      // set the current permissions from the acl entry
      setCurrent(lookup);
      System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
      System.out.println("Current ACL Settings for " + p_leaf.getName() + " on realm " + node.getName());
      System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
      dump(lookup);
      // now set those which have changed
      setChanges();
      // change the entry in the acl
      p_leaf.modACLEntry(changeACLEntry(lookup));
      // set the node acl to the new acl list
      System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
      System.out.println("New ACL Settings for " + p_leaf.getName() + " on realm " + node.getName());
      System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
      dump(lookup);
    } catch (Exception e) {
      e.printStackTrace();
    }
  }

  /**
   * search the enumeration of child nodes for other realms and channels
   */
  private void searchNodes(Enumeration enum1) {
    while (enum1.hasMoreElements()) {
      Object obj = enum1.nextElement();
      if (obj instanceof nLeafNode) {
        nLeafNode leaf = (nLeafNode) obj;
        String fullyQualifiedName = leaf.getAbsolutePath();
        System.out.println("Found channel " + fullyQualifiedName);
        if (pattern) {
          if ((leaf.isChannel()) && (fullyQualifiedName.indexOf(channelName) != -1)) {
            // we have found a channel that matches the name specified, so set the permissions
            setChannel(leaf);
          }
        } else if (factory) {
          if ((leaf.isChannel()) && (fullyQualifiedName.startsWith(channelName))) {
            // we have found a channel that matches the name specified, so set the permissions
            setChannel(leaf);
          }
        } else if ((leaf.isChannel()) && (fullyQualifiedName.equals(channelName))) {
          // we have found a channel that matches the name specified, so set the permissions
          setChannel(leaf);
        }
      } else if (obj instanceof nRealmNode) {
        // we have found another realm node, so search this node for channels
        searchNode((nRealmNode) obj);
      } else if (obj instanceof nContainer) {
        nContainer cont = (nContainer) obj;
        searchNodes(cont.getNodes());
      }
    }
  }

  /**
   * Search the children of the realm passed as a paremeter
   */
  private void searchNode(nRealmNode p_node) {
    try {
      System.out.println("Found node " + p_node.getName());
      searchNodes(p_node.getNodes());
    } catch (Exception ex) {
      ex.printStackTrace();
    }
  }

  /**
   * Change an acl entry and set the permissions based on the permissions flags
   */
  public nChannelACLEntry changeACLEntry(nChannelACLEntry aclEntry) {
    return this.setPermissions(aclEntry);
  }

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

  /**
   * This will set the permissions flags to what the current acl settings are
   * This is so that only those permissions that you wish to change are changed
   */
  public void setCurrent(nChannelACLEntry entry) {
    canListAcl = entry.canList();
    canModifyAcl = entry.canModify();
    fullPrivileges = entry.hasFullPrivileges();
    canGetLastEid = entry.canGetLastEID();
    canRead = entry.canRead();
    canWrite = entry.canWrite();
    canPurge = entry.canPurge();
    canNamed = entry.canUseNamedSubscription();
  }

  /**
   * Set the permissions on the channel acl entry
   */
  public nChannelACLEntry setPermissions(nChannelACLEntry aclEntry) {
    aclEntry.setList(canListAcl);
    aclEntry.setModify(canModifyAcl);
    aclEntry.setFullPrivileges(fullPrivileges);
    aclEntry.setGetLastEID(canGetLastEid);
    aclEntry.setRead(canRead);
    aclEntry.setWrite(canWrite);
    aclEntry.setPurge(canPurge);
    aclEntry.setUseNamedSubscription(canNamed);
    return aclEntry;
  }

  /**
   * Output to system.out the permissions the current permissions on the acl entry
   */
  public void dump(nChannelACLEntry entry) {
    System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
    System.out.println("List ACL               : " + entry.canList());
    System.out.println("Set ACL                : " + entry.canModify());
    System.out.println("Full Privileges        : " + entry.hasFullPrivileges());
    System.out.println("Get Last EID           : " + entry.canGetLastEID());
    System.out.println("Read channel           : " + entry.canRead());
    System.out.println("Write to channel       : " + entry.canWrite());
    System.out.println("Purge channel          : " + entry.canPurge());
    System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
  }

  /**
   * Output to system.out the permissions that will be set
   */
  public void dump() {
    System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
    System.out.println("ACL will be set to.... ");
    System.out.println("~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~");
    System.out.println("List ACL               : " + canListAcl);
    System.out.println("Set ACL                : " + canModifyAcl);
    System.out.println("Full Privileges        : " + fullPrivileges);
    System.out.println("Get Last EID           : " + canGetLastEid);
    System.out.println("Read channel           : " + canRead);
    System.out.println("Write to channel       : " + canWrite);
    System.out.println("Purge channel          : " + canPurge);
    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);
    } else if (name.equals(everyone)) {
      name = "*";
    }
    host = System.getProperty("HOST", null);
    if (host == null) {
      Usage();
      System.exit(1);
    } else if (host.equals(everywhere)) {
      host = "*";
    }
    channelName = System.getProperty("CHANNEL", null);
    if (channelName == null) {
      Usage();
      System.exit(1);
    }
    if (channelName.indexOf("%") != -1) {
      if (channelName.startsWith("%") && channelName.endsWith("%")) {
        channelName = channelName.substring(1);
        channelName = channelName.substring(0, channelName.length() - 1);
        pattern = true;
      }
      if (channelName.endsWith("%")) {
        channelName = channelName.substring(0, channelName.length() - 1);
        factory = true;
      }
    }
  }

  /**
   * This method will set the permissions flags, if the command line arguments have been
   * passed for specific permissions.
   * The command line arguments are + or - for either add or remove permission, followed
   * by the actual permission flag
   */
  public void setChanges() {
    for (int i = 0; i < changeArgs.length; i++) {
      boolean hasPermission;
      if (changeArgs[i].startsWith("+")) {
        hasPermission = true;
      } else if (changeArgs[i].startsWith("-")) {
        hasPermission = false;
      } else {
        continue;
      }
      String permission = changeArgs[i].substring(1);
      System.out.println("operation " + hasPermission + " for permission " + permission);
      if (permission.equalsIgnoreCase("list_acl")) {
        canListAcl = hasPermission;
      } else if (permission.equalsIgnoreCase("modify_acl")) {
        canModifyAcl = hasPermission;
      } else if (permission.equalsIgnoreCase("full")) {
        fullPrivileges = hasPermission;
      } else if (permission.equalsIgnoreCase("read")) {
        canRead = hasPermission;
      } else if (permission.equalsIgnoreCase("write")) {
        canWrite = hasPermission;
      } else if (permission.equalsIgnoreCase("purge")) {
        canPurge = hasPermission;
      } else if (permission.equalsIgnoreCase("named")) {
        canNamed = hasPermission;
      } else if (permission.equalsIgnoreCase("all_perms")) {
        canListAcl = hasPermission;
        canModifyAcl = hasPermission;
        canGetLastEid = hasPermission;
        canRead = hasPermission;
        canWrite = hasPermission;
        canPurge = hasPermission;
        canNamed = hasPermission;
      }
    }
  }

  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("CHANNEL", args[0]);
        getOptions(null);
        break;
      case 2:
        System.setProperty("CHANNEL", args[0]);
        System.setProperty("NAME", args[1]);
        getOptions(null);
        break;
      default:
        System.setProperty("CHANNEL", args[0]);
        System.setProperty("NAME", args[1]);
        System.setProperty("HOST", args[2]);
        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
   * CHANNEL
   * as system properties, and pass in a list of permissions in the constructor
   */
  public static void main(String[] args) {
    processEnvironmentVariables();

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

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

    System.out.println("Usage ...\n");
    System.out.println(
        "nchangechanacl <channel name> <user> <host> [+/-list_acl] [+/-modify_acl] [+/-full] [+/-last_eid] [+/-read] [+/-write] [+/-purge] [+/-named] [+/-all_perms]\n");
    System.out.println("<Required Arguments> \n");
    System.out.println("<channel name> - Channel name parameter for the channel to change the ACL entry for");
    System.out.println("<user> - User name parameter for the channel to change the ACL entry for");
    System.out.println("<host> - Host name parameter for the channel to change the ACL entry for");
    System.out.println("\n[Optional Arguments] \n");
    System.out.println("[+/-] - Prepending + or - specifies whether to add or remove a permission");
    System.out.println("[list_acl] - Specifies that the list acl permission should be added/removed");
    System.out.println("[modify_acl] - Specifies that the modify acl permission should be added/removed");
    System.out.println("[full] - Specifies that the full permission should be added/removed");
    System.out.println("[last_eid] - Specifies that the get last EID permission should be added/removed");
    System.out.println("[read] - Specifies that the read permission should be added/removed");
    System.out.println("[write] - Specifies that the write permission should be added/removed");
    System.out.println("[purge] - Specifies that the purge permission should be added/removed");
    System.out.println("[named] - Specifies that the used named subscriber permission should be added/removed");
    System.out.println("[all_perms] - Specifies that all permissions should be added/removed");
    System.out.println("\n\nNote: -? provides help on environment variables \n");
  }
}