package au.gov.amsa.ais.message;
   
   import static au.gov.amsa.ais.Util.areEqual;
   import static au.gov.amsa.ais.Util.checkMessageId;
   import static au.gov.amsa.ais.Util.getAisExtractorFactory;
   
   import au.gov.amsa.ais.AisExtractor;
   import au.gov.amsa.ais.AisExtractorFactory;
   import au.gov.amsa.ais.AisMessageType;
  import au.gov.amsa.ais.AisParseException;
  import au.gov.amsa.ais.Communications;
  import au.gov.amsa.ais.HasCommunications;
  import au.gov.amsa.ais.Util;
  
  public class AisPositionB implements AisPosition, HasCommunications {
  
      private static final Integer TRUE_HEADING_NOT_AVAILABLE = 511;
      private static final Integer COG_NOT_AVAILABLE = 3600;
      private static final Integer SOG_NOT_AVAILABLE = 1023;
      private static final Integer LONGITUDE_NOT_AVAILABLE = 181 * 600000; // 108600000;
      private static final Integer LATITUDE_NOT_AVAILABLE = 91 * 600000; // 54600000;
      private final AisExtractor extractor;
      private final String source;
      private final int messageId;
      private final int mmsi;
      private final Double longitude;
      private final Double latitude;
  
      public AisPositionB(String message, String source, int padBits) {
          this(getAisExtractorFactory(), message, source, padBits);
      }
  
      public AisPositionB(String message, int padBits) {
          this(getAisExtractorFactory(), message, null, padBits);
      }
  
      public AisPositionB(AisExtractorFactory factory, String message, String source, int padBits) {
          this.source = source;
          this.extractor = factory.create(message, 133, padBits);
          messageId = extractor.getMessageId();
          checkMessageId(getMessageId(), AisMessageType.POSITION_REPORT_CLASS_B);
  
          mmsi = extractor.getValue(8, 38);
          longitude = extractLongitude(extractor);
          latitude = extractLatitude(extractor);
      }
  
      static Integer extractTrueHeading(AisExtractor extractor) {
          try {
              int val = extractor.getValue(124, 133);
              if (val == TRUE_HEADING_NOT_AVAILABLE)
                  return null;
              else if (val > 359) {
                  // have seen 404, might be corrupted message
                  return null;
              } else
                  return val;
          } catch (AisParseException e) {
              return null;
          }
      }
  
      static Double extractCourseOverGround(AisExtractor extractor) {
          try {
              int val = extractor.getValue(112, 124);
              if (val == COG_NOT_AVAILABLE || val >= 3600)
                  return null;
              else
                  return val / 10.0;
          } catch (AisParseException e) {
              return null;
          }
      }
  
      static Double extractSpeedOverGround(AisExtractor extractor) {
          int val = extractor.getValue(46, 56);
          if (val == SOG_NOT_AVAILABLE)
              return null;
          else
              return val / 10.0;
      }
  
      static Double extractLongitude(AisExtractor extractor) {
          int val = extractor.getSignedValue(57, 85);
          if (val == LONGITUDE_NOT_AVAILABLE) {
              return null;
          } else {
              Util.checkLong(val / 600000.0);
              return val / 600000.0;
          }
      }
  
      static Double extractLatitude(AisExtractor extractor) {
          int val = extractor.getSignedValue(85, 112);
          if (val == LATITUDE_NOT_AVAILABLE) {
              return null;
          } else {
              Util.checkLat(val / 600000.0);
              return val / 600000.0;
         }
     }
 
     @Override
     public int getMessageId() {
         return messageId;
     }
 
     @Override
     public int getRepeatIndicator() {
         return extractor.getValue(6, 8);
     }
 
     @Override
     public int getMmsi() {
         return mmsi;
     }
 
     public int getSpare() {
         return extractor.getValue(38, 46);
     }
 
     @Override
     public Double getSpeedOverGroundKnots() {
         return extractSpeedOverGround(extractor);
     }
 
     @Override
     public boolean isHighAccuracyPosition() {
         return areEqual(extractor.getValue(56, 57), 1);
     }
 
     @Override
     public Double getLongitude() {
         return longitude;
     }
 
     @Override
     public Double getLatitude() {
         return latitude;
     }
 
     @Override
     public Double getCourseOverGround() {
         return extractCourseOverGround(extractor);
     }
 
     @Override
     public Integer getTrueHeading() {
         return extractTrueHeading(extractor);
     }
 
     @Override
     public int getTimeSecondsOnly() {
         return extractor.getValue(133, 139);
     }
 
     public int getSpare2() {
         return extractor.getValue(139, 141);
     }
 
     public boolean isSotdmaUnit() {
         return areEqual(extractor.getValue(141, 142), 0);
     }
 
     public boolean isEquippedWithIntegratedDisplayForMessages12And14() {
         return areEqual(extractor.getValue(142, 143), 1);
     }
 
     public boolean isEquippedWithDscFunction() {
         return areEqual(extractor.getValue(143, 144), 1);
     }
 
     public boolean canOperateOverWholeMarineBand() {
         return areEqual(extractor.getValue(144, 145), 1);
     }
 
     public boolean canManageFrequenciesViaMessage22() {
         return areEqual(extractor.getValue(145, 146), 1);
     }
 
     public boolean isStationOperatingInAssignedMode() {
         return areEqual(extractor.getValue(146, 147), 1);
     }
 
     @Override
     public boolean isUsingRAIM() {
         return areEqual(extractor.getValue(147, 148), 1);
     }
 
     public boolean isITDMACommunicationState() {
         return areEqual(extractor.getValue(148, 149), 1);
     }
 
     @Override
     public Communications getCommunications() {
         return new Communications(extractor, 149);
     }
 
     @Override
     public String getSource() {
         return source;
     }
 
     @Override
     public String toString() {
         StringBuilder builder = new StringBuilder();
         builder.append("AisPositionB [source=");
         builder.append(source);
         builder.append(", messageId=");
         builder.append(messageId);
         builder.append(", repeatIndicator=");
         builder.append(getRepeatIndicator());
         builder.append(", mmsi=");
         builder.append(mmsi);
         builder.append(", spare=");
         builder.append(getSpare());
         builder.append(", speedOverGroundKnots=");
         builder.append(getSpeedOverGroundKnots());
         builder.append(", isHighAccuracyPosition=");
         builder.append(isHighAccuracyPosition());
         builder.append(", longitude=");
         builder.append(longitude);
         builder.append(", latitude=");
         builder.append(latitude);
         builder.append(", courseOverGround=");
         builder.append(getCourseOverGround());
         builder.append(", trueHeading=");
         builder.append(getTrueHeading());
         builder.append(", timeSecondsOnly=");
         builder.append(getTimeSecondsOnly());
         builder.append(", spare2=");
         builder.append(getSpare2());
         builder.append(", isSotdmaUnit=");
         builder.append(isSotdmaUnit());
         builder.append(", isEquippedWithIntegratedDisplayForMessages12And14=");
         builder.append(isEquippedWithIntegratedDisplayForMessages12And14());
         builder.append(", isEquippedWithDscFunction=");
         builder.append(isEquippedWithDscFunction());
         builder.append(", canOperateOverWholeMarineBand=");
         builder.append(canOperateOverWholeMarineBand());
         builder.append(", canManageFrequenciesViaMessage22=");
         builder.append(canManageFrequenciesViaMessage22());
         builder.append(", isStationOperatingInAssignedMode=");
         builder.append(isStationOperatingInAssignedMode());
         builder.append(", isUsingRAIM=");
         builder.append(isUsingRAIM());
         builder.append(", isITDMACommunicationState=");
         builder.append(isITDMACommunicationState());
         builder.append(", communications=");
         builder.append(getCommunications());
         builder.append("]");
         return builder.toString();
     }
 
 }