/* Copyright 2004, 2005, 2006 Acegi Technology Pty Limited

  *

  * 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.acegisecurity.intercept.web;

 import java.beans.PropertyEditorSupport;

 import java.io.BufferedReader;

 import java.io.IOException;

 import java.io.StringReader;

 import java.util.ArrayList;

 import java.util.List;

 import org.acegisecurity.util.StringSplitUtils;

 import org.apache.commons.logging.Log;

 import org.apache.commons.logging.LogFactory;

 import org.springframework.util.StringUtils;

 /**

  * Property editor to assist with the setup of a {@link FilterInvocationDefinitionSource}.<p>The class creates and

  * populates a {@link RegExpBasedFilterInvocationDefinitionMap} or {@link PathBasedFilterInvocationDefinitionMap}

  * (depending on the type of patterns presented).</p>

  *  <p>By default the class treats presented patterns as regular expressions. If the keyword

  * <code>PATTERN_TYPE_APACHE_ANT</code> is present (case sensitive), patterns will be treated as Apache Ant paths

  * rather than regular expressions.</p>

  *

  * @author Ben Alex

  * @version $Id: FilterInvocationDefinitionSourceEditor.java 1784 2007-02-24 21:00:24Z luke_t $

  */

 public class FilterInvocationDefinitionSourceEditor extends PropertyEditorSupport {

     //~ Static fields/initializers =====================================================================================

     private static final Log logger = LogFactory.getLog(FilterInvocationDefinitionSourceEditor.class);

     public static final String DIRECTIVE_CONVERT_URL_TO_LOWERCASE_BEFORE_COMPARISON =

             "CONVERT_URL_TO_LOWERCASE_BEFORE_COMPARISON";

     public static final String DIRECTIVE_PATTERN_TYPE_APACHE_ANT = "PATTERN_TYPE_APACHE_ANT";

     //~ Methods ========================================================================================================

     public void setAsText(String s) throws IllegalArgumentException {

         FilterInvocationDefinitionDecorator source = new FilterInvocationDefinitionDecorator();

         if ((s == null) || "".equals(s)) {

             // Leave target object empty

             source.setDecorated(new RegExpBasedFilterInvocationDefinitionMap());

         } else {

             // Check if we need to override the default definition map

             if (s.lastIndexOf(DIRECTIVE_PATTERN_TYPE_APACHE_ANT) != -1) {

                 source.setDecorated(new PathBasedFilterInvocationDefinitionMap());

                 if (logger.isDebugEnabled()) {

                     logger.debug(("Detected " + DIRECTIVE_PATTERN_TYPE_APACHE_ANT

                         + " directive; using Apache Ant style path expressions"));

                 }

             } else {

                 source.setDecorated(new RegExpBasedFilterInvocationDefinitionMap());

             }

             if (s.lastIndexOf(DIRECTIVE_CONVERT_URL_TO_LOWERCASE_BEFORE_COMPARISON) != -1) {

                 if (logger.isDebugEnabled()) {

                     logger.debug("Detected " + DIRECTIVE_CONVERT_URL_TO_LOWERCASE_BEFORE_COMPARISON

                         + " directive; Instructing mapper to convert URLs to lowercase before comparison");

                 }

                 source.setConvertUrlToLowercaseBeforeComparison(true);

             }

             BufferedReader br = new BufferedReader(new StringReader(s));

             int counter = 0;

             String line;

             List mappings = new ArrayList();

             while (true) {

                 counter++;

                 try {

                     line = br.readLine();

                 } catch (IOException ioe) {

                     throw new IllegalArgumentException(ioe.getMessage());

                 }

                 if (line == null) {

                     break;

                 }

                 line = line.trim();

                 if (logger.isDebugEnabled()) {

                     logger.debug("Line " + counter + ": " + line);

                 }

                 if (line.startsWith("//")) {

                     continue;

                 }

                 // Attempt to detect malformed lines (as per SEC-204)

                 if (line.lastIndexOf(DIRECTIVE_CONVERT_URL_TO_LOWERCASE_BEFORE_COMPARISON) != -1) {

                     // Directive found; check for second directive or name=value

                     if ((line.lastIndexOf(DIRECTIVE_PATTERN_TYPE_APACHE_ANT) != -1) || (line.lastIndexOf("=") != -1)) {

                         throw new IllegalArgumentException("Line appears to be malformed: " + line);

                     }

                 }

                 // Attempt to detect malformed lines (as per SEC-204)

                 if (line.lastIndexOf(DIRECTIVE_PATTERN_TYPE_APACHE_ANT) != -1) {

                     // Directive found; check for second directive or name=value

                     if ((line.lastIndexOf(DIRECTIVE_CONVERT_URL_TO_LOWERCASE_BEFORE_COMPARISON) != -1)

                         || (line.lastIndexOf("=") != -1)) {

                         throw new IllegalArgumentException("Line appears to be malformed: " + line);

                     }

                 }

                 // Skip lines that are not directives

                 if (line.lastIndexOf('=') == -1) {

                     continue;

                 }

                 if (line.lastIndexOf("==") != -1) {

                     throw new IllegalArgumentException("Only single equals should be used in line " + line);

                 }

                 // Tokenize the line into its name/value tokens

                 // As per SEC-219, use the LAST equals as the delimiter between LHS and RHS

                 String name = StringSplitUtils.substringBeforeLast(line, "=");

                 String value = StringSplitUtils.substringAfterLast(line, "=");

                 if (!StringUtils.hasText(name) || !StringUtils.hasText(value)) {

                     throw new IllegalArgumentException("Failed to parse a valid name/value pair from " + line);

                 }

                 // Attempt to detect malformed lines (as per SEC-204)

                 if (source.isConvertUrlToLowercaseBeforeComparison()

                     && source.getDecorated() instanceof PathBasedFilterInvocationDefinitionMap) {

                     // Should all be lowercase; check each character

                     // We only do this for Ant (regexp have control chars)

                     for (int i = 0; i < name.length(); i++) {

                         String character = name.substring(i, i + 1);

                         if (!character.toLowerCase().equals(character)) {

                             throw new IllegalArgumentException("You are using the "

                                 + DIRECTIVE_CONVERT_URL_TO_LOWERCASE_BEFORE_COMPARISON

                                 + " with Ant Paths, yet you have specified an uppercase character in line: " + line

                                 + " (character '" + character + "')");

                         }

                     }

                 }

                 FilterInvocationDefinitionSourceMapping mapping = new FilterInvocationDefinitionSourceMapping();

                 mapping.setUrl(name);

                 String[] tokens = org.springframework.util.StringUtils

                         .commaDelimitedListToStringArray(value);

                 for (int i = 0; i < tokens.length; i++) {

                     mapping.addConfigAttribute(tokens[i].trim());

                 }

                 mappings.add(mapping);

             }

             source.setMappings(mappings);

         }

         setValue(source.getDecorated());

     }

 }