/* Copyright 2002-2012 Space Applications Services
    * Licensed to CS Systèmes d'Information (CS) under one or more
    * contributor license agreements.  See the NOTICE file distributed with
    * this work for additional information regarding copyright ownership.
    * CS 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.orekit.files.sp3;
  
  import java.io.Serializable;
  import java.util.ArrayList;
  import java.util.Collection;
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.LinkedList;
  import java.util.List;
  import java.util.Map;
  
  import org.orekit.files.general.OrbitFile;
  import org.orekit.files.general.SatelliteInformation;
  import org.orekit.files.general.SatelliteTimeCoordinate;
  import org.orekit.time.AbsoluteDate;
  
  /** Represents a parsed SP3 orbit file.
   * @author Thomas Neidhart
   */
  public class SP3File implements OrbitFile, Serializable {
  
      /** Serializable UID. */
      private static final long serialVersionUID = 3333652174843017654L;
  
      /** File type indicator. */
      public enum SP3FileType {
          /** GPS only file. */
          GPS,
          /** Mixed file. */
          MIXED,
          /** GLONASS only file. */
          GLONASS,
          /** LEO only file. */
          LEO,
          /** Galileo only file. */
          GALILEO,
          /** COMPASS only file. */
          COMPASS,
          /** QZSS only file. */
          QZSS,
          /** undefined file format. */
          UNDEFINED
      }
  
      /** Orbit type indicator. */
      public enum SP3OrbitType {
          /** fitted. */
          FIT,
          /** extrapolated or predicted. */
          EXT,
          /** broadcast. */
          BCT,
          /** fitted after applying a Helmert transformation. */
          HLM;
  
          /** Parse a string to get the type.
           * @param s string to parse
           * @return the type corresponding to the string
           * @exception IllegalArgumentException if the string does not correspond to a type
           */
          public static SP3OrbitType parseType(final String s) {
              final String normalizedString = s.trim().toUpperCase();
              if ("EST".equals(normalizedString)) {
                  return FIT;
              } else {
                  return valueOf(normalizedString);
              }
          }
  
      }
  
      /** File type. */
      private SP3FileType type;
  
      /** Time system. */
      private TimeSystem timeSystem;
  
      /** Epoch of the file. */
      private AbsoluteDate epoch;
  
      /** GPS week. */
      private int gpsWeek;
  
     /** Seconds of the current GPS week. */
     private double secondsOfWeek;
 
     /** Julian day. */
     private int julianDay;
 
     /** Day fraction. */
     private double dayFraction;
 
     /** Time-interval between epochs. */
     private double epochInterval;
 
     /** Number of epochs. */
     private int numberOfEpochs;
 
     /** Coordinate system. */
     private String coordinateSystem;
 
     /** Data used indicator. */
     private String dataUsed;
 
     /** Orbit type. */
     private SP3OrbitType orbitType;
 
     /** Agency providing the file. */
     private String agency;
 
     /** A list containing additional satellite information. */
     private List<SatelliteInformation> satellites;
 
     /** A mapping of satellite id to its corresponding {@link SatelliteInformation} object. */
     private Map<String, SatelliteInformation> satelliteInfo;
 
     /** A map containing all satellite coordinates. */
     private Map<String, List<SatelliteTimeCoordinate>> satelliteCoords;
 
     /** Create a new SP3 file object. */
     public SP3File() {
         satellites = new ArrayList<SatelliteInformation>();
         satelliteInfo = new HashMap<String, SatelliteInformation>();
         satelliteCoords = new HashMap<String, List<SatelliteTimeCoordinate>>();
     }
 
     /** Returns the {@link SP3FileType} associated with this SP3 file.
      * @return the file type for this SP3 file
      */
     public SP3FileType getType() {
         return type;
     }
 
     /** Set the file type for this SP3 file.
      * @param fileType the file type to be set
      */
     public void setType(final SP3FileType fileType) {
         this.type = fileType;
     }
 
     /** {@inheritDoc} */
     public TimeSystem getTimeSystem() {
         return timeSystem;
     }
 
     /** Set the time system used in this SP3 file.
      * @param system the time system to be set
      */
     public void setTimeSystem(final TimeSystem system) {
         this.timeSystem = system;
     }
 
     /** Returns the data used indicator from the SP3 file.
      * @return the data used indicator (unparsed)
      */
     public String getDataUsed() {
         return dataUsed;
     }
 
     /** Set the data used indicator for this SP3 file.
      * @param data the data used indicator to be set
      */
     public void setDataUsed(final String data) {
         this.dataUsed = data;
     }
 
     /** {@inheritDoc} */
     public AbsoluteDate getEpoch() {
         return epoch;
     }
 
     /** Set the epoch of the SP3 file.
      * @param time the epoch to be set
      */
     public void setEpoch(final AbsoluteDate time) {
         this.epoch = time;
     }
 
     /** Returns the GPS week as contained in the SP3 file.
      * @return the GPS week of the SP3 file
      */
     public int getGpsWeek() {
         return gpsWeek;
     }
 
     /** Set the GPS week of the SP3 file.
      * @param week the GPS week to be set
      */
     public void setGpsWeek(final int week) {
         this.gpsWeek = week;
     }
 
     /** Returns the seconds of the GPS week as contained in the SP3 file.
      * @return the seconds of the GPS week
      */
     public double getSecondsOfWeek() {
         return secondsOfWeek;
     }
 
     /** Set the seconds of the GPS week for this SP3 file.
      * @param seconds the seconds to be set
      */
     public void setSecondsOfWeek(final double seconds) {
         this.secondsOfWeek = seconds;
     }
 
     /** Returns the julian day for this SP3 file.
      * @return the julian day
      */
     public int getJulianDay() {
         return julianDay;
     }
 
     /** Set the julian day for this SP3 file.
      * @param day the julian day to be set
      */
     public void setJulianDay(final int day) {
         this.julianDay = day;
     }
 
     /** Returns the day fraction for this SP3 file.
      * @return the day fraction
      */
     public double getDayFraction() {
         return dayFraction;
     }
 
     /** Set the day fraction for this SP3 file.
      * @param fraction the day fraction to be set
      */
     public void setDayFraction(final double fraction) {
         this.dayFraction = fraction;
     }
 
     /** {@inheritDoc} */
     public double getEpochInterval() {
         return epochInterval;
     }
 
     /** Set the epoch interval for this SP3 file.
      * @param interval the interval between orbit entries
      */
     public void setEpochInterval(final double interval) {
         this.epochInterval = interval;
     }
 
     /** {@inheritDoc} */
     public int getNumberOfEpochs() {
         return numberOfEpochs;
     }
 
     /** Set the number of epochs as contained in the SP3 file.
      * @param epochCount the number of epochs to be set
      */
     public void setNumberOfEpochs(final int epochCount) {
         this.numberOfEpochs = epochCount;
     }
 
     /** {@inheritDoc} */
     public String getCoordinateSystem() {
         return coordinateSystem;
     }
 
     /** Set the coordinate system used for the orbit entries.
      * @param system the coordinate system to be set
      */
     public void setCoordinateSystem(final String system) {
         this.coordinateSystem = system;
     }
 
     /** Returns the {@link SP3OrbitType} for this SP3 file.
      * @return the orbit type
      */
     public SP3OrbitType getOrbitType() {
         return orbitType;
     }
 
     /** Set the {@link SP3OrbitType} for this SP3 file.
      * @param oType the orbit type to be set
      */
     public void setOrbitType(final SP3OrbitType oType) {
         this.orbitType = oType;
     }
 
     /** Returns the agency that prepared this SP3 file.
      * @return the agency
      */
     public String getAgency() {
         return agency;
     }
 
     /** Set the agency string for this SP3 file.
      * @param agencyStr the agency string to be set
      */
     public void setAgency(final String agencyStr) {
         this.agency = agencyStr;
     }
 
     /** Add a new satellite with a given identifier to the list of
      * stored satellites.
      * @param satId the satellite identifier
      */
     public void addSatellite(final String satId) {
         // only add satellites which have not been added before
         if (getSatellite(satId) == null) {
             final SatelliteInformation info = new SatelliteInformation(satId);
             satellites.add(info);
             satelliteInfo.put(satId, info);
             satelliteCoords.put(satId, new LinkedList<SatelliteTimeCoordinate>());
         }
     }
 
     /** {@inheritDoc} */
     public Collection<SatelliteInformation> getSatellites() {
         return Collections.unmodifiableCollection(satellites);
     }
 
     /** {@inheritDoc} */
     public int getSatelliteCount() {
         return satellites.size();
     }
 
     /** {@inheritDoc} */
     public SatelliteInformation getSatellite(final String satId) {
         if (satId == null) {
             return null;
         }
 
         return satelliteInfo.get(satId);
     }
 
     /** Returns the nth satellite as contained in the SP3 file.
      * @param n the index of the satellite
      * @return a {@link SatelliteInformation} object for the nth satellite
      */
     public SatelliteInformation getSatellite(final int n) {
         return satellites.get(n);
     }
 
     /** {@inheritDoc} */
     public boolean containsSatellite(final String satId) {
         return satelliteCoords.containsKey(satId);
     }
 
     /** {@inheritDoc} */
     public List<SatelliteTimeCoordinate> getSatelliteCoordinates(final String satId) {
         return satelliteCoords.get(satId);
     }
 
     /** Adds a new P/V coordinate for a given satellite.
      * @param satId the satellite identifier
      * @param coord the P/V coordinate of the satellite
      */
     public void addSatelliteCoordinate(final String satId, final SatelliteTimeCoordinate coord) {
         final List<SatelliteTimeCoordinate> coords = satelliteCoords.get(satId);
         if (coords != null) {
             coords.add(coord);
         }
     }
 }