/**
 * 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
 *
 *     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.nutch.net;

import org.apache.nutch.plugin.Extension;
import org.apache.nutch.plugin.ExtensionPoint;
import org.apache.nutch.plugin.PluginRepository;

import org.apache.hadoop.conf.Configuration;

import org.apache.nutch.util.NutchConfiguration;

import java.io.BufferedReader;
import java.io.InputStreamReader;

/**
 * Checks one given filter or all filters.
 * 
 * @author John Xing
 */
public class URLFilterChecker {

  private Configuration conf;

  public URLFilterChecker(Configuration conf) {
    this.conf = conf;
  }

  private void checkOne(String filterName) throws Exception {
    URLFilter filter = null;

    ExtensionPoint point = PluginRepository.get(conf).getExtensionPoint(
        URLFilter.X_POINT_ID);

    if (point == null)
      throw new RuntimeException(URLFilter.X_POINT_ID + " not found.");

    Extension[] extensions = point.getExtensions();

    for (int i = 0; i < extensions.length; i++) {
      Extension extension = extensions[i];
      filter = (URLFilter) extension.getExtensionInstance();
      if (filter.getClass().getName().equals(filterName)) {
        break;
      } else {
        filter = null;
      }
    }

    if (filter == null)
      throw new RuntimeException("Filter " + filterName + " not found.");

    // jerome : should we keep this behavior?
    // if (LogFormatter.hasLoggedSevere())
    // throw new RuntimeException("Severe error encountered.");

    System.out.println("Checking URLFilter " + filterName);

    BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
    String line;
    while ((line = in.readLine()) != null) {
      String out = filter.filter(line);
      if (out != null) {
        System.out.print("+");
        System.out.println(out);
      } else {
        System.out.print("-");
        System.out.println(line);
      }
    }
  }

  private void checkAll() throws Exception {
    System.out.println("Checking combination of all URLFilters available");

    BufferedReader in = new BufferedReader(new InputStreamReader(System.in));
    String line;
    while ((line = in.readLine()) != null) {
      URLFilters filters = new URLFilters(this.conf);
      String out = filters.filter(line);
      if (out != null) {
        System.out.print("+");
        System.out.println(out);
      } else {
        System.out.print("-");
        System.out.println(line);
      }
    }
  }

  public static void main(String[] args) throws Exception {

    String usage = "Usage: URLFilterChecker (-filterName filterName | -allCombined)";

    if (args.length == 0) {
      System.err.println(usage);
      System.exit(-1);
    }

    String filterName = null;
    if (args[0].equals("-filterName")) {
      if (args.length != 2) {
        System.err.println(usage);
        System.exit(-1);
      }
      filterName = args[1];
    }

    URLFilterChecker checker = new URLFilterChecker(NutchConfiguration.create());
    if (filterName != null) {
      checker.checkOne(filterName);
    } else {
      checker.checkAll();
    }

    System.exit(0);
  }
}
