/**
 * Copyright (c) 2010, Sebastian Sdorra All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * 1. Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the following disclaimer. 2. Redistributions in
 * binary form must reproduce the above copyright notice, this list of
 * conditions and the following disclaimer in the documentation and/or other
 * materials provided with the distribution. 3. Neither the name of SCM-Manager;
 * nor the names of its contributors may be used to endorse or promote products
 * derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * http://bitbucket.org/sdorra/scm-manager
 *
 */



package sonia.scm.security;

//~--- non-JDK imports --------------------------------------------------------

import com.google.common.base.Splitter;

import org.apache.shiro.authz.Permission;
import org.apache.shiro.authz.permission.PermissionResolver;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import sonia.scm.repository.PermissionType;

//~--- JDK imports ------------------------------------------------------------

import java.util.Iterator;

/**
 *
 * @author Sebastian Sdorra
 */
public class RepositoryPermissionResolver implements PermissionResolver
{

  /** Field description */
  private static final String TYPE_REPOSITORY = "repository";

  /**
   * the logger for RepositoryPermissionResolver
   */
  private static final Logger logger =
    LoggerFactory.getLogger(RepositoryPermissionResolver.class);

  //~--- methods --------------------------------------------------------------

  /**
   * Method description
   *
   *
   * @param permissionString
   *
   * @return
   */
  @Override
  public Permission resolvePermission(String permissionString)
  {
    RepositoryPermission permission = null;
    Iterator<String> permissionIt =
      Splitter.on(':').omitEmptyStrings().trimResults().split(
        permissionString).iterator();

    if (permissionIt.hasNext())
    {
      String type = permissionIt.next();

      if (type.equals(TYPE_REPOSITORY))
      {
        permission = createRepositoryPermission(permissionIt);
      }
      else if (logger.isWarnEnabled())
      {
        logger.warn("permission '{}' is not a repository permission",
          permissionString);
      }
    }

    return permission;
  }

  /**
   * Method description
   *
   *
   * @param permissionIt
   *
   * @return
   */
  private RepositoryPermission createRepositoryPermission(
    Iterator<String> permissionIt)
  {
    RepositoryPermission permission = null;

    if (permissionIt.hasNext())
    {
      String repositoryId = permissionIt.next();

      if (permissionIt.hasNext())
      {
        try
        {
          PermissionType type = PermissionType.valueOf(permissionIt.next());

          permission = new RepositoryPermission(repositoryId, type);
        }
        catch (IllegalArgumentException ex)
        {
          logger.warn("type is not a valid permission type", ex);
        }
      }
      else if (logger.isWarnEnabled())
      {
        logger.warn("permission type is missing");
      }
    }
    else if (logger.isWarnEnabled())
    {
      logger.warn("repository id and permission type is missing");
    }

    return permission;
  }
}