/*
 * Copyright 1999-2005 The 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.
 */
package org.apache.log4j.lf5.viewer.categoryexplorer;

import org.apache.log4j.lf5.LogRecord;
import org.apache.log4j.lf5.LogRecordFilter;

import java.util.Enumeration;

/**
 * An implementation of LogRecordFilter based on a CategoryExplorerModel
 *
 * @author Richard Wan
 */

// Contributed by ThoughtWorks Inc.

public class CategoryExplorerLogRecordFilter implements LogRecordFilter {
  //--------------------------------------------------------------------------
  //   Constants:
  //--------------------------------------------------------------------------

  //--------------------------------------------------------------------------
  //   Protected Variables:
  //--------------------------------------------------------------------------

  protected CategoryExplorerModel _model;

  //--------------------------------------------------------------------------
  //   Private Variables:
  //--------------------------------------------------------------------------

  //--------------------------------------------------------------------------
  //   Constructors:
  //--------------------------------------------------------------------------

  public CategoryExplorerLogRecordFilter(CategoryExplorerModel model) {
    _model = model;
  }

  //--------------------------------------------------------------------------
  //   Public Methods:
  //--------------------------------------------------------------------------

  /**
   * @return true if the CategoryExplorer model specified at construction
   * is accepting the category of the specified LogRecord.  Has a side-effect
   * of adding the CategoryPath of the LogRecord to the explorer model
   * if the CategoryPath is new.
   */
  public boolean passes(LogRecord record) {
    CategoryPath path = new CategoryPath(record.getCategory());
    return _model.isCategoryPathActive(path);
  }

  /**
   * Resets the counters for the contained CategoryNodes to zero.
   */
  public void reset() {
    resetAllNodes();
  }

  //--------------------------------------------------------------------------
  //   Protected Methods:
  //--------------------------------------------------------------------------

  protected void resetAllNodes() {
    Enumeration nodes = _model.getRootCategoryNode().depthFirstEnumeration();
    CategoryNode current;
    while (nodes.hasMoreElements()) {
      current = (CategoryNode) nodes.nextElement();
      current.resetNumberOfContainedRecords();
      _model.nodeChanged(current);
    }
  }
  //--------------------------------------------------------------------------
  //   Private Methods:
  //--------------------------------------------------------------------------

  //--------------------------------------------------------------------------
  //   Nested Top-Level Classes or Interfaces
  //--------------------------------------------------------------------------
}