/*
    * Copyright (c) 2002-2025 Gargoyle Software Inc.
    *
    * 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
    * https://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.htmlunit.javascript.proxyautoconfig;
  
  import java.net.InetAddress;
  import java.text.SimpleDateFormat;
  import java.util.Calendar;
  import java.util.Locale;
  import java.util.TimeZone;
  
  import org.apache.commons.lang3.StringUtils;
  import org.htmlunit.javascript.HtmlUnitScriptable;
  import org.htmlunit.javascript.JavaScriptEngine;
  import org.htmlunit.javascript.configuration.JsxClass;
  import org.htmlunit.javascript.configuration.JsxFunction;
  import org.htmlunit.util.SubnetUtils;
  
  /**
   * Provides an implementation of Proxy Auto-Config (PAC).
   *
   * @see <a href=
   * "https://developer.mozilla.org/en-US/docs/Web/HTTP/Proxy_servers_and_tunneling/Proxy_Auto-Configuration_PAC_file">
   * Proxy Auto-Configuration (PAC) file</a>
   *
   * @author Ahmed Ashour
   * @author Ronald Brill
   */
  @JsxClass
  public final class ProxyAutoConfig extends HtmlUnitScriptable {
  
      private static final String TIMEZONE_GMT = "GMT";
  
      private ProxyAutoConfig() {
          super();
      }
  
      /**
       * Returns true if there is no domain name in the hostname (no dots).
       * @param host the hostname from the URL (excluding port number).
       * @return true if there is no domain name in the hostname (no dots).
       */
      @JsxFunction
      public static boolean isPlainHostName(final String host) {
          return host.indexOf('.') == -1;
      }
  
      /**
       * Returns true if the domain of hostname matches.
       * @param host the hostname from the URL
       * @param domain the domain name to test the hostname against
       * @return true if the domain of hostname matches.
       */
      @JsxFunction
      public static boolean dnsDomainIs(final String host, final String domain) {
          return host.endsWith(domain);
      }
  
      /**
       * Returns true if the hostname matches exactly the specified hostname,
       * or if there is no domain name part in the hostname, but the unqualified hostname matches.
       * @param host the hostname from the URL
       * @param hostdom fully qualified hostname to match against
       * @return true if the hostname matches exactly the specified hostname,
       *         or if there is no domain name part in the hostname, but the unqualified hostname matches.
       */
      @JsxFunction
      public static boolean localHostOrDomainIs(final String host, final String hostdom) {
          return host.length() > 1 && host.equals(hostdom) || host.indexOf('.') == -1 && hostdom.startsWith(host);
      }
  
      /**
       * Tries to resolve the hostname. Returns true if succeeds.
       * @param host the hostname from the URL.
       * @return true if the specific hostname is resolvable.
       */
      @JsxFunction
      public static boolean isResolvable(final String host) {
          return dnsResolve(host) != null;
      }
  
      /**
       * Returns true if the IP address of the host matches the specified IP address pattern.
       * @param host a DNS hostname, or IP address.
       *        If a hostname is passed, it will be resolved into an IP address by this function.
       * @param pattern an IP address pattern in the dot-separated format
       * @param mask mask for the IP address pattern informing which parts of the IP address should be matched against.
       *        0 means ignore, 255 means match
      * @return true if the IP address of the host matches the specified IP address pattern.
      */
     @JsxFunction
     public static boolean isInNet(final String host, final String pattern, final String mask) {
         final String dnsResolve = dnsResolve(host);
         if (null == dnsResolve) {
             return false;
         }
 
         final SubnetUtils subnetUtils = new SubnetUtils(pattern, mask);
         return subnetUtils.isInRange(dnsResolve);
     }
 
     /**
      * Resolves the given DNS hostname into an IP address, and returns it in the dot separated format as a string.
      * @param host the hostname to resolve
      * @return the resolved IP address
      */
     @JsxFunction
     public static String dnsResolve(final String host) {
         try {
             return InetAddress.getByName(host).getHostAddress();
         }
         catch (final Exception e) {
             return null;
         }
     }
 
     /**
      * Returns the IP address of the local host, as a string in the dot-separated integer format.
      * @return the IP address of the local host, as a string in the dot-separated integer format.
      */
     @JsxFunction
     public static String myIpAddress() {
         try {
             return InetAddress.getLocalHost().getHostAddress();
         }
         catch (final Exception e) {
             throw JavaScriptEngine.throwAsScriptRuntimeEx(e);
         }
     }
 
     /**
      * Returns the number (integer) of DNS domain levels (number of dots) in the hostname.
      * @param host the hostname from the URL
      * @return the number (integer) of DNS domain levels (number of dots) in the hostname.
      */
     @JsxFunction
     public static int dnsDomainLevels(final String host) {
         int levels = 0;
         for (int i = host.length() - 1; i >= 0; i--) {
             if (host.charAt(i) == '.') {
                 levels++;
             }
         }
         return levels;
     }
 
     /**
      * Matches the specified string against a shell expression, not regular expression.
      * @param str a string to match
      * @param shexp the shell expression
      * @return if the string matches
      */
     @JsxFunction
     public static boolean shExpMatch(final String str, final String shexp) {
         final String regexp = shexp.replace(".", "\\.").replace("*", ".*").replace("?", ".");
         return str.matches(regexp);
     }
 
     /**
      * Checks if today is included in the specified range.
      * @param wd1 week day 1
      * @param wd2 week day 2, optional
      * @param gmt string of "GMT", or not specified
      * @return if today is in range
      */
     @JsxFunction
     public static boolean weekdayRange(final String wd1, Object wd2, final Object gmt) {
         TimeZone timezone = TimeZone.getDefault();
         if (TIMEZONE_GMT.equals(JavaScriptEngine.toString(gmt))
                 || TIMEZONE_GMT.equals(JavaScriptEngine.toString(wd2))) {
             timezone = TimeZone.getTimeZone(TIMEZONE_GMT);
         }
         if (JavaScriptEngine.isUndefined(wd2) || TIMEZONE_GMT.equals(JavaScriptEngine.toString(wd2))) {
             wd2 = wd1;
         }
         final Calendar calendar = Calendar.getInstance(timezone);
         for (int i = 0; i < 7; i++) {
             final String day = new SimpleDateFormat("EEE", Locale.ROOT)
                     .format(calendar.getTime()).toUpperCase(Locale.ROOT);
             if (day.equals(wd2)) {
                 return true;
             }
             if (day.equals(wd1)) {
                 return i == 0;
             }
             calendar.add(Calendar.DAY_OF_WEEK, 1);
         }
         return false;
     }
 
     /**
      * Checks if today is included in the specified range.
      * @param value1 the value 1
      * @param value2 the value 2
      * @param value3 the value 3
      * @param value4 the value 4
      * @param value5 the value 5
      * @param value6 the value 6
      * @param value7 the value 7
      * @return if today is in range
      */
     @JsxFunction
     public static boolean dateRange(final String value1, final Object value2, final Object value3,
             final Object value4, final Object value5, final Object value6, final Object value7) {
         final Object[] values = {value1, value2, value3, value4, value5, value6, value7};
         TimeZone timezone = TimeZone.getDefault();
 
         //actual values length
         int length;
         for (length = values.length - 1; length >= 0; length--) {
             if (TIMEZONE_GMT.equals(JavaScriptEngine.toString(values[length]))) {
                 timezone = TimeZone.getTimeZone(TIMEZONE_GMT);
                 break;
             }
             else if (!JavaScriptEngine.isUndefined(values[length])) {
                 length++;
                 break;
             }
         }
 
         final int day1;
         final int day2;
         final int month1;
         final int month2;
         final int year1;
         final int year2;
         final Calendar cal1;
         final Calendar cal2;
         switch (length) {
             case 1:
                 final int day = getSmallInt(value1);
                 final int month = dateRange_getMonth(value1);
                 final int year = dateRange_getYear(value1);
                 cal1 = dateRange_createCalendar(timezone, day, month, year);
                 cal2 = (Calendar) cal1.clone();
                 break;
 
             case 2:
                 day1 = getSmallInt(value1);
                 month1 = dateRange_getMonth(value1);
                 year1 = dateRange_getYear(value1);
                 cal1 = dateRange_createCalendar(timezone, day1, month1, year1);
                 day2 = getSmallInt(value2);
                 month2 = dateRange_getMonth(value2);
                 year2 = dateRange_getYear(value2);
                 cal2 = dateRange_createCalendar(timezone, day2, month2, year2);
                 break;
 
             case 4:
                 day1 = getSmallInt(value1);
                 if (day1 != -1) {
                     month1 = dateRange_getMonth(value2);
                     day2 = getSmallInt(value3);
                     month2 = dateRange_getMonth(value4);
                     cal1 = dateRange_createCalendar(timezone, day1, month1, -1);
                     cal2 = dateRange_createCalendar(timezone, day2, month2, -1);
                 }
                 else {
                     month1 = dateRange_getMonth(value1);
                     year1 = dateRange_getMonth(value2);
                     month2 = getSmallInt(value3);
                     year2 = dateRange_getMonth(value4);
                     cal1 = dateRange_createCalendar(timezone, -1, month1, year1);
                     cal2 = dateRange_createCalendar(timezone, -1, month2, year2);
                 }
                 break;
 
             default:
                 day1 = getSmallInt(value1);
                 month1 = dateRange_getMonth(value2);
                 year1 = dateRange_getYear(value3);
                 day2 = getSmallInt(value4);
                 month2 = dateRange_getMonth(value5);
                 year2 = dateRange_getYear(value6);
                 cal1 = dateRange_createCalendar(timezone, day1, month1, year1);
                 cal2 = dateRange_createCalendar(timezone, day2, month2, year2);
         }
 
         final Calendar today = Calendar.getInstance(timezone);
         today.set(Calendar.MILLISECOND, 0);
         today.set(Calendar.SECOND, 0);
         cal1.set(Calendar.MILLISECOND, 0);
         cal1.set(Calendar.SECOND, 0);
         cal2.set(Calendar.MILLISECOND, 0);
         cal2.set(Calendar.SECOND, 0);
         return today.equals(cal1) || (today.after(cal1) && today.before(cal2)) || today.equals(cal2);
     }
 
     private static Calendar dateRange_createCalendar(final TimeZone timezone,
             final int day, final int month, final int year) {
         final Calendar calendar = Calendar.getInstance(timezone);
         if (day != -1) {
             calendar.set(Calendar.DAY_OF_MONTH, day);
         }
         if (month != -1) {
             calendar.set(Calendar.MONTH, month);
         }
         if (year != -1) {
             calendar.set(Calendar.YEAR, year);
         }
         return calendar;
     }
 
     private static int getSmallInt(final Object object) {
         final String s = JavaScriptEngine.toString(object);
         if (Character.isDigit(s.charAt(0))) {
             final int i = Integer.parseInt(s);
             if (i < 70) {
                 return i;
             }
         }
         return -1;
     }
 
     private static int dateRange_getMonth(final Object object) {
         final String s = JavaScriptEngine.toString(object);
         if (Character.isLetter(s.charAt(0))) {
             try {
                 final Calendar cal = Calendar.getInstance(Locale.ROOT);
                 cal.clear();
                 cal.setTime(new SimpleDateFormat("MMM", Locale.ROOT).parse(s));
                 return cal.get(Calendar.MONTH);
             }
             catch (final Exception ignored) {
                 // empty
             }
         }
         return -1;
     }
 
     private static int dateRange_getYear(final Object object) {
         final String s = JavaScriptEngine.toString(object);
         if (Character.isDigit(s.charAt(0))) {
             final int i = Integer.parseInt(s);
             if (i > 1000) {
                 return i;
             }
         }
         return -1;
     }
 
     /**
      * Checks if the time now is included in the specified range.
      * @param value1 the value 1
      * @param value2 the value 2
      * @param value3 the value 3
      * @param value4 the value 4
      * @param value5 the value 5
      * @param value6 the value 6
      * @param value7 the value 7
      * @return if the time now is in the range
      */
     @JsxFunction
     public static boolean timeRange(final String value1, final Object value2, final Object value3,
             final Object value4, final Object value5, final Object value6, final Object value7) {
         final Object[] values = {value1, value2, value3, value4, value5, value6, value7};
         TimeZone timezone = TimeZone.getDefault();
 
         //actual values length
         int length;
         for (length = values.length - 1; length >= 0; length--) {
             if (TIMEZONE_GMT.equals(JavaScriptEngine.toString(values[length]))) {
                 timezone = TimeZone.getTimeZone(TIMEZONE_GMT);
                 break;
             }
             else if (!JavaScriptEngine.isUndefined(values[length])) {
                 length++;
                 break;
             }
         }
 
         final int hour1;
         final int hour2;
         final int min1;
         final int min2;
         final int second1;
         final int second2;
         final Calendar cal1;
         final Calendar cal2;
         switch (length) {
             case 1:
                 hour1 = getSmallInt(value1);
                 cal1 = timeRange_createCalendar(timezone, hour1, -1, -1);
                 cal2 = (Calendar) cal1.clone();
                 cal2.add(Calendar.HOUR_OF_DAY, 1);
                 break;
 
             case 2:
                 hour1 = getSmallInt(value1);
                 cal1 = timeRange_createCalendar(timezone, hour1, -1, -1);
                 hour2 = getSmallInt(value2);
                 cal2 = timeRange_createCalendar(timezone, hour2, -1, -1);
                 break;
 
             case 4:
                 hour1 = getSmallInt(value1);
                 min1 = getSmallInt(value2);
                 hour2 = getSmallInt(value3);
                 min2 = getSmallInt(value4);
                 cal1 = dateRange_createCalendar(timezone, hour1, min1, -1);
                 cal2 = dateRange_createCalendar(timezone, hour2, min2, -1);
                 break;
 
             default:
                 hour1 = getSmallInt(value1);
                 min1 = getSmallInt(value2);
                 second1 = getSmallInt(value3);
                 hour2 = getSmallInt(value4);
                 min2 = getSmallInt(value5);
                 second2 = getSmallInt(value6);
                 cal1 = dateRange_createCalendar(timezone, hour1, min1, second1);
                 cal2 = dateRange_createCalendar(timezone, hour2, min2, second2);
         }
 
         final Calendar now = Calendar.getInstance(timezone);
         return now.equals(cal1) || now.after(cal1) && now.before(cal2) || now.equals(cal2);
     }
 
     private static Calendar timeRange_createCalendar(final TimeZone timezone,
             final int hour, final int minute, final int second) {
         final Calendar calendar = Calendar.getInstance(timezone);
         if (hour != -1) {
             calendar.set(Calendar.HOUR_OF_DAY, hour);
         }
         if (minute != -1) {
             calendar.set(Calendar.MINUTE, minute);
         }
         if (second != -1) {
             calendar.set(Calendar.SECOND, second);
         }
         return calendar;
     }
 
     /**
      * Concatenates the four dot-separated bytes into one 4-byte word and converts it to decimal.
      * @param ip any dotted address such as an IP address or mask.
      * @return concatenates the four dot-separated bytes into one 4-byte word and converts it to decimal.
      */
     @JsxFunction(functionName = "convert_addr")
     public static long convertAddr(final String ip) {
         final String[] parts = StringUtils.split(ip, '.');
 
         return
             ((Integer.parseInt(parts[0]) & 0xff) << 24)
                 | ((Integer.parseInt(parts[1]) & 0xff) << 16)
                 | ((Integer.parseInt(parts[2]) & 0xff) << 8)
                 | (Integer.parseInt(parts[3]) & 0xff);
     }
 }