/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you 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
 *
 *   https://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.
 */
package org.apache.accumulo.shell.commands;

import java.util.Map;
import java.util.Set;

import org.apache.accumulo.core.security.NamespacePermission;
import org.apache.accumulo.core.security.SystemPermission;
import org.apache.accumulo.core.security.TablePermission;
import org.apache.accumulo.core.util.BadArgumentException;
import org.apache.accumulo.shell.Shell;
import org.apache.accumulo.shell.Shell.Command;
import org.apache.accumulo.shell.ShellOptions;
import org.apache.accumulo.shell.Token;
import org.apache.commons.cli.CommandLine;
import org.apache.commons.cli.Option;
import org.apache.commons.cli.OptionGroup;
import org.apache.commons.cli.Options;

public class RevokeCommand extends TableOperation {
  {
    disableUnflaggedTableOptions();
  }

  private Option systemOpt;
  private Option userOpt;
  private String user;
  private String[] permission;

  @Override
  public int execute(final String fullCommand, final CommandLine cl, final Shell shellState)
      throws Exception {
    user = cl.hasOption(userOpt.getOpt()) ? cl.getOptionValue(userOpt.getOpt())
        : shellState.getAccumuloClient().whoami();

    permission = cl.getArgs()[0].split("\\.", 2);
    if (permission[0].equalsIgnoreCase("System")) {
      if (cl.hasOption(systemOpt.getOpt())) {
        try {
          shellState.getAccumuloClient().securityOperations().revokeSystemPermission(user,
              SystemPermission.valueOf(permission[1]));
          Shell.log.debug("Revoked from {} the {} permission", user, permission[1]);
        } catch (IllegalArgumentException e) {
          throw new BadArgumentException("No such system permission", fullCommand,
              fullCommand.indexOf(cl.getArgs()[0]));
        }
      } else {
        throw new BadArgumentException(
            "Missing required option for granting System Permission: -s ", fullCommand,
            fullCommand.indexOf(cl.getArgs()[0]));
      }
    } else if (permission[0].equalsIgnoreCase("Table")) {
      super.execute(fullCommand, cl, shellState);
    } else if (permission[0].equalsIgnoreCase("Namespace")) {
      if (cl.hasOption(optNamespace.getOpt())) {
        try {
          shellState.getAccumuloClient().securityOperations().revokeNamespacePermission(user,
              cl.getOptionValue(optNamespace.getOpt()), NamespacePermission.valueOf(permission[1]));
        } catch (IllegalArgumentException e) {
          throw new BadArgumentException("No such namespace permission", fullCommand,
              fullCommand.indexOf(cl.getArgs()[0]));
        }
      } else {
        throw new BadArgumentException("No namespace specified to apply permission to", fullCommand,
            fullCommand.indexOf(cl.getArgs()[0]));
      }
    } else {
      throw new BadArgumentException("Unrecognized permission", fullCommand,
          fullCommand.indexOf(cl.getArgs()[0]));
    }
    return 0;
  }

  @Override
  protected void doTableOp(final Shell shellState, final String tableName) throws Exception {
    try {
      shellState.getAccumuloClient().securityOperations().revokeTablePermission(user, tableName,
          TablePermission.valueOf(permission[1]));
      Shell.log.debug("Revoked from {} the {} permission on table {}", user, permission[1],
          tableName);
    } catch (IllegalArgumentException e) {
      throw new IllegalArgumentException("No such table permission", e);
    }
  }

  @Override
  public String description() {
    return "revokes system or table permissions from a user";
  }

  @Override
  public String usage() {
    return getName() + " <permission>";
  }

  @Override
  public void registerCompletion(final Token root,
      final Map<Command.CompletionSet,Set<String>> completionSet) {
    final Token cmd = new Token(getName());
    cmd.addSubcommand(new Token(TablePermission.printableValues()));
    cmd.addSubcommand(new Token(SystemPermission.printableValues()));
    cmd.addSubcommand(new Token(NamespacePermission.printableValues()));
    root.addSubcommand(cmd);
  }

  @Override
  public Options getOptions() {
    super.getOptions();
    final Options o = new Options();

    final OptionGroup group = new OptionGroup();

    systemOpt = new Option("s", "system", false, "revoke a system permission");

    optNamespace = new Option(ShellOptions.namespaceOption, "namespace", true,
        "name of a namespace to operate on");
    optNamespace.setArgName("namespace");

    group.addOption(systemOpt);
    group.addOption(optTableName);
    group.addOption(optTablePattern);
    group.addOption(optNamespace);

    o.addOptionGroup(group);
    userOpt = new Option(ShellOptions.userOption, "user", true, "user to operate on");
    userOpt.setArgName("username");
    userOpt.setRequired(true);
    o.addOption(userOpt);

    return o;
  }

  @Override
  public int numArgs() {
    return 1;
  }
}
