/*
    * Copyright  2004-2005 Stefan Reuter
    *
    *  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 net.sf.asterisk.fastagi.impl;
  
  import java.io.Serializable;
  import java.io.UnsupportedEncodingException;
  import java.net.InetAddress;
  import java.net.URLDecoder;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.HashMap;
  import java.util.Iterator;
  import java.util.List;
  import java.util.Map;
  import java.util.StringTokenizer;
  import java.util.regex.Matcher;
  import java.util.regex.Pattern;
  
  import net.sf.asterisk.fastagi.AGIRequest;
  import net.sf.asterisk.util.Log;
  import net.sf.asterisk.util.LogFactory;
  
  /***
   * Default implementation of the AGIRequest interface.
   * 
   * @author srt
   * @version $Id: AGIRequestImpl.java,v 1.11 2005/11/27 16:08:17 srt Exp $
   */
  public class AGIRequestImpl implements Serializable, AGIRequest
  {
      private final Log logger = LogFactory.getLog(getClass());
      private static final Pattern SCRIPT_PATTERN = Pattern
              .compile("^([^//?]*)//?(.*)$");
      private static final Pattern PARAMETER_PATTERN = Pattern
              .compile("^(.*)=(.*)$");
  
      private String rawCallerId;
  
      /***
       * Serial version identifier.
       */
      private static final long serialVersionUID = 3257001047145789496L;
  
      private Map request;
  
      /***
       * A map assigning the values of a parameter (an array of Strings) to the
       * name of the parameter.
       */
      private Map parameterMap;
  
      private String parameters;
      private String script;
      private boolean callerIdCreated;
      private InetAddress localAddress;
      private int localPort;
      private InetAddress remoteAddress;
      private int remotePort;
  
      /***
       * Creates a new AGIRequestImpl.
       * 
       * @param environment the first lines as received from Asterisk containing
       *            the environment.
       */
      public AGIRequestImpl(final Collection environment)
      {
          if (environment == null)
          {
              throw new IllegalArgumentException("Environment must not be null.");
          }
          request = buildMap(environment);
      }
  
      /***
       * Builds a map containing variable names as key (with the "agi_" prefix
       * stripped) and the corresponding values.<br>
       * Syntactically invalid and empty variables are skipped.
       * 
       * @param lines the environment to transform.
       * @return a map with the variables set corresponding to the given
       *         environment.
       */
      private Map buildMap(final Collection lines)
      {
         Map map;
         Iterator lineIterator;
 
         map = new HashMap();
         lineIterator = lines.iterator();
 
         while (lineIterator.hasNext())
         {
             String line;
             int colonPosition;
             String key;
             String value;
 
             line = (String) lineIterator.next();
             colonPosition = line.indexOf(':');
 
             // no colon on the line?
             if (colonPosition < 0)
             {
                 continue;
             }
 
             // key doesn't start with agi_?
             if (!line.startsWith("agi_"))
             {
                 continue;
             }
 
             // first colon in line is last character -> no value present?
             if (line.length() < colonPosition + 2)
             {
                 continue;
             }
 
             key = line.substring(4, colonPosition).toLowerCase();
             value = line.substring(colonPosition + 2);
 
             if (value.length() != 0)
             {
                 map.put(key, value);
             }
         }
 
         return map;
     }
 
     public Map getRequest()
     {
         return request;
     }
 
     /***
      * Returns the name of the script to execute.
      * 
      * @return the name of the script to execute.
      */
     public synchronized String getScript()
     {
         if (script != null)
         {
             return script;
         }
 
         script = (String) request.get("network_script");
         if (script != null)
         {
             Matcher scriptMatcher = SCRIPT_PATTERN.matcher(script);
             if (scriptMatcher.matches())
             {
                 script = scriptMatcher.group(1);
                 parameters = scriptMatcher.group(2);
             }
         }
 
         return script;
     }
 
     /***
      * Returns the full URL of the request in the form
      * agi://host[:port][/script].
      * 
      * @return the full URL of the request in the form
      *         agi://host[:port][/script].
      */
     public String getRequestURL()
     {
         return (String) request.get("request");
     }
 
     /***
      * Returns the name of the channel.
      * 
      * @return the name of the channel.
      */
     public String getChannel()
     {
         return (String) request.get("channel");
     }
 
     /***
      * Returns the unqiue id of the channel.
      * 
      * @return the unqiue id of the channel.
      */
     public String getUniqueId()
     {
         return (String) request.get("uniqueid");
     }
 
     public String getType()
     {
         return (String) request.get("type");
     }
 
     public String getLanguage()
     {
         return (String) request.get("language");
     }
 
     public String getCallerId()
     {
         String callerIdName;
         String callerId;
 
         callerIdName = (String) request.get("calleridname");
         callerId = (String) request.get("callerid");
         if (callerIdName != null)
         {
             // Asterisk 1.2
             if (callerId == null || "unknown".equals(callerId))
             {
                 return null;
             }
 
             return callerId;
         }
         else
         {
             // Asterisk 1.0
             return getCallerId10();
         }
     }
 
     public String getCallerIdName()
     {
         String callerIdName;
 
         callerIdName = (String) request.get("calleridname");
         if (callerIdName != null)
         {
             // Asterisk 1.2
             if ("unknown".equals(callerIdName))
             {
                 return null;
             }
 
             return callerIdName;
         }
         else
         {
             // Asterisk 1.0
             return getCallerIdName10();
         }
     }
 
     /***
      * Returns the Caller*ID using Asterisk 1.0 logic.
      * 
      * @return the Caller*ID
      */
     private String getCallerId10()
     {
         int lbPosition;
         int rbPosition;
 
         if (!callerIdCreated)
         {
             rawCallerId = (String) request.get("callerid");
             callerIdCreated = true;
         }
 
         if (rawCallerId == null)
         {
             return null;
         }
 
         lbPosition = rawCallerId.indexOf('<');
         rbPosition = rawCallerId.indexOf('>');
 
         if (lbPosition < 0 || rbPosition < 0)
         {
             return rawCallerId;
         }
 
         return rawCallerId.substring(lbPosition + 1, rbPosition);
     }
 
     /***
      * Returns the Caller*ID using Asterisk 1.0 logic.
      * 
      * @return the Caller*ID Name
      */
     private String getCallerIdName10()
     {
         int lbPosition;
         String callerIdName;
 
         if (!callerIdCreated)
         {
             rawCallerId = (String) request.get("callerid");
             callerIdCreated = true;
         }
 
         if (rawCallerId == null)
         {
             return null;
         }
 
         lbPosition = rawCallerId.indexOf('<');
 
         if (lbPosition < 0)
         {
             return null;
         }
 
         callerIdName = rawCallerId.substring(0, lbPosition).trim();
         if (callerIdName.startsWith("\"") && callerIdName.endsWith("\""))
         {
             callerIdName = callerIdName.substring(1, callerIdName.length() - 1);
         }
 
         if (callerIdName.length() == 0)
         {
             return null;
         }
         else
         {
             return callerIdName;
         }
     }
 
     public String getDnid()
     {
         String dnid;
         
         dnid = (String) request.get("dnid");
         
         if (dnid == null || "unknown".equals(dnid))
         {
             return null;
         }
         
         return dnid; 
     }
 
     public String getRdnis()
     {
         String rdnis;
         
         rdnis = (String) request.get("rdnis");
         
         if (rdnis == null || "unknown".equals(rdnis))
         {
             return null;
         }
         
         return rdnis; 
     }
 
     public String getContext()
     {
         return (String) request.get("context");
     }
 
     public String getExtension()
     {
         return (String) request.get("extension");
     }
 
     public Integer getPriority()
     {
         if (request.get("priority") != null)
         {
             return new Integer((String) request.get("priority"));
         }
         return null;
     }
 
     public Boolean getEnhanced()
     {
         if (request.get("enhanced") != null)
         {
             if ("1.0".equals((String) request.get("enhanced")))
             {
                 return Boolean.TRUE;
             }
             else
             {
                 return Boolean.FALSE;
             }
         }
         return null;
     }
 
     public String getAccountCode()
     {
         return (String) request.get("accountCode");
     }
 
     public Integer getCallingAni2()
     {
         if (request.get("callingani2") == null)
         {
             return null;
         }
         
         try
         {
             return Integer.valueOf((String) request.get("callingani2"));
         }
         catch (NumberFormatException e)
         {
             return null;
         }
     }
 
     public Integer getCallingPres()
     {
         if (request.get("callingpres") == null)
         {
             return null;
         }
         
         try
         {
             return Integer.valueOf((String) request.get("callingpres"));
         }
         catch (NumberFormatException e)
         {
             return null;
         }
     }
 
     public Integer getCallingTns()
     {
         if (request.get("callingtns") == null)
         {
             return null;
         }
         
         try
         {
             return Integer.valueOf((String) request.get("callingtns"));
         }
         catch (NumberFormatException e)
         {
             return null;
         }
     }
 
     public Integer getCallingTon()
     {
         if (request.get("callington") == null)
         {
             return null;
         }
         
         try
         {
             return Integer.valueOf((String) request.get("callington"));
         }
         catch (NumberFormatException e)
         {
             return null;
         }
     }
 
     public String getParameter(String name)
     {
         String[] values;
 
         values = getParameterValues(name);
 
         if (values == null || values.length == 0)
         {
             return null;
         }
 
         return values[0];
     }
 
     public String[] getParameterValues(String name)
     {
         if (getParameterMap().isEmpty())
         {
             return null;
         }
 
         return (String[]) parameterMap.get(name);
     }
 
     public synchronized Map getParameterMap()
     {
         if (parameterMap == null)
         {
             parameterMap = parseParameters(parameters);
         }
         return parameterMap;
     }
 
     /***
      * Parses the given parameter string and caches the result.
      * 
      * @param s the parameter string to parse
      * @return a Map made up of parameter names their values
      */
     private synchronized Map parseParameters(String s)
     {
         Map parameterMap;
         Map result;
         Iterator parameterIterator;
         StringTokenizer st;
 
         parameterMap = new HashMap();
         if (s == null)
         {
             return parameterMap;
         }
 
         st = new StringTokenizer(s, "&");
         while (st.hasMoreTokens())
         {
             String parameter;
             Matcher parameterMatcher;
             String name;
             String value;
             List values;
 
             parameter = st.nextToken();
             parameterMatcher = PARAMETER_PATTERN.matcher(parameter);
             if (parameterMatcher.matches())
             {
                 try
                 {
                     name = URLDecoder
                             .decode(parameterMatcher.group(1), "UTF-8");
                     value = URLDecoder.decode(parameterMatcher.group(2),
                             "UTF-8");
                 }
                 catch (UnsupportedEncodingException e)
                 {
                     logger.error("Unable to decode parameter '" + parameter
                             + "'", e);
                     continue;
                 }
             }
             else
             {
                 try
                 {
                     name = URLDecoder.decode(parameter, "UTF-8");
                     value = "";
                 }
                 catch (UnsupportedEncodingException e)
                 {
                     logger.error("Unable to decode parameter '" + parameter
                             + "'", e);
                     continue;
                 }
             }
 
             if (parameterMap.get(name) == null)
             {
                 values = new ArrayList();
                 values.add(value);
                 parameterMap.put(name, values);
             }
             else
             {
                 values = (List) parameterMap.get(name);
                 values.add(value);
             }
         }
 
         result = new HashMap();
         parameterIterator = parameterMap.keySet().iterator();
         while (parameterIterator.hasNext())
         {
             String name;
             List values;
             String[] valueArray;
 
             name = (String) parameterIterator.next();
             values = (List) parameterMap.get(name);
 
             valueArray = new String[values.size()];
             result.put(name, values.toArray(valueArray));
         }
 
         return result;
     }
 
     public InetAddress getLocalAddress()
     {
         return localAddress;
     }
 
     public void setLocalAddress(InetAddress localAddress)
     {
         this.localAddress = localAddress;
     }
 
     public int getLocalPort()
     {
         return localPort;
     }
 
     public void setLocalPort(int localPort)
     {
         this.localPort = localPort;
     }
 
     public InetAddress getRemoteAddress()
     {
         return remoteAddress;
     }
 
     public void setRemoteAddress(InetAddress remoteAddress)
     {
         this.remoteAddress = remoteAddress;
     }
 
     public int getRemotePort()
     {
         return remotePort;
     }
 
     public void setRemotePort(int remotePort)
     {
         this.remotePort = remotePort;
     }
 
     public String toString()
     {
         StringBuffer sb;
 
         sb = new StringBuffer(getClass().getName() + ": ");
         sb.append("script='" + getScript() + "'; ");
         sb.append("requestURL='" + getRequestURL() + "'; ");
         sb.append("channel='" + getChannel() + "'; ");
         sb.append("uniqueId='" + getUniqueId() + "'; ");
         sb.append("type='" + getType() + "'; ");
         sb.append("language='" + getLanguage() + "'; ");
         sb.append("callerId='" + getCallerId() + "'; ");
         sb.append("callerIdName='" + getCallerIdName() + "'; ");
         sb.append("dnid='" + getDnid() + "'; ");
         sb.append("rdnis='" + getRdnis() + "'; ");
         sb.append("context='" + getContext() + "'; ");
         sb.append("extension='" + getExtension() + "'; ");
         sb.append("priority='" + getPriority() + "'; ");
         sb.append("enhanced='" + getEnhanced() + "'; ");
         sb.append("accountCode='" + getAccountCode() + "'; ");
         sb.append("systemHashcode=" + System.identityHashCode(this));
 
         return sb.toString();
     }
 }