OpmParser.java

/* Copyright 2002-2021 CS GROUP
 * Licensed to CS GROUP (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.ccsds.ndm.odm.opm;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

import org.orekit.data.DataContext;
import org.orekit.files.ccsds.ndm.ParsedUnitsBehavior;
import org.orekit.files.ccsds.ndm.odm.CartesianCovariance;
import org.orekit.files.ccsds.ndm.odm.CartesianCovarianceKey;
import org.orekit.files.ccsds.ndm.odm.CommonMetadata;
import org.orekit.files.ccsds.ndm.odm.CommonMetadataKey;
import org.orekit.files.ccsds.ndm.odm.OdmParser;
import org.orekit.files.ccsds.ndm.odm.KeplerianElements;
import org.orekit.files.ccsds.ndm.odm.KeplerianElementsKey;
import org.orekit.files.ccsds.ndm.odm.OdmMetadataKey;
import org.orekit.files.ccsds.ndm.odm.SpacecraftParameters;
import org.orekit.files.ccsds.ndm.odm.SpacecraftParametersKey;
import org.orekit.files.ccsds.ndm.odm.StateVector;
import org.orekit.files.ccsds.ndm.odm.StateVectorKey;
import org.orekit.files.ccsds.ndm.odm.UserDefined;
import org.orekit.files.ccsds.section.CommentsContainer;
import org.orekit.files.ccsds.section.Header;
import org.orekit.files.ccsds.section.HeaderProcessingState;
import org.orekit.files.ccsds.section.MetadataKey;
import org.orekit.files.ccsds.section.Segment;
import org.orekit.files.ccsds.section.XmlStructureProcessingState;
import org.orekit.files.ccsds.utils.ContextBinding;
import org.orekit.files.ccsds.utils.FileFormat;
import org.orekit.files.ccsds.utils.lexical.ParseToken;
import org.orekit.files.ccsds.utils.lexical.TokenType;
import org.orekit.files.ccsds.utils.lexical.UserDefinedXmlTokenBuilder;
import org.orekit.files.ccsds.utils.lexical.XmlTokenBuilder;
import org.orekit.files.ccsds.utils.parsing.ErrorState;
import org.orekit.files.ccsds.utils.parsing.ProcessingState;
import org.orekit.time.AbsoluteDate;
import org.orekit.utils.IERSConventions;

/** A parser for the CCSDS OPM (Orbit Parameter Message).
 * <p>
 * Note than starting with Orekit 11.0, CCSDS message parsers are
 * mutable objects that gather the data being parsed, until the
 * message is complete and the {@link #parseMessage(org.orekit.data.DataSource)
 * parseMessage} method has returned. This implies that parsers
 * should <em>not</em> be used in a multi-thread context. The recommended
 * way to use parsers is to either dedicate one parser for each message
 * and drop it afterwards, or to use a single-thread loop.
 * </p>
 * @author sports
 * @author Luc Maisonobe
 * @since 6.1
 */
public class OpmParser extends OdmParser<Opm, OpmParser> {

    /** Default mass to use if there are no spacecraft parameters block logical block in the file. */
    private final double defaultMass;

    /** File header. */
    private Header header;

    /** File segments. */
    private List<Segment<CommonMetadata, OpmData>> segments;

    /** OPM metadata being read. */
    private CommonMetadata metadata;

    /** Context binding valid for current metadata. */
    private ContextBinding context;

    /** State vector logical block being read. */
    private StateVector stateVectorBlock;

    /** Keplerian elements logical block being read. */
    private KeplerianElements keplerianElementsBlock;

    /** Spacecraft parameters logical block being read. */
    private SpacecraftParameters spacecraftParametersBlock;

    /** Covariance matrix logical block being read. */
    private CartesianCovariance covarianceBlock;

    /** Current maneuver. */
    private Maneuver currentManeuver;

    /** All maneuvers. */
    private List<Maneuver> maneuverBlocks;

    /** User defined parameters. */
    private UserDefined userDefinedBlock;

    /** Processor for global message structure. */
    private ProcessingState structureProcessor;

    /** Complete constructor.
     * <p>
     * Calling this constructor directly is not recommended. Users should rather use
     * {@link org.orekit.files.ccsds.ndm.ParserBuilder#buildOpmParser()
     * parserBuilder.buildOpmParser()}.
     * </p>
     * @param conventions IERS Conventions
     * @param simpleEOP if true, tidal effects are ignored when interpolating EOP
     * @param dataContext used to retrieve frames, time scales, etc.
     * @param missionReferenceDate reference date for Mission Elapsed Time or Mission Relative Time time systems
     * @param mu gravitational coefficient
     * @param defaultMass default mass to use if there are no spacecraft parameters block logical block in the file
     * @param parsedUnitsBehavior behavior to adopt for handling parsed units
     */
    public OpmParser(final IERSConventions conventions, final boolean simpleEOP,
                     final DataContext dataContext,
                     final AbsoluteDate missionReferenceDate, final double mu,
                     final double defaultMass, final ParsedUnitsBehavior parsedUnitsBehavior) {
        super(Opm.ROOT, Opm.FORMAT_VERSION_KEY, conventions, simpleEOP, dataContext,
              missionReferenceDate, mu, parsedUnitsBehavior);
        this.defaultMass = defaultMass;
    }

    /** {@inheritDoc} */
    @Override
    public Map<String, XmlTokenBuilder> getSpecialXmlElementsBuilders() {

        final Map<String, XmlTokenBuilder> builders = super.getSpecialXmlElementsBuilders();

        // special handling of user-defined parameters
        builders.put(UserDefined.USER_DEFINED_XML_TAG, new UserDefinedXmlTokenBuilder());

        return builders;

    }

    /** {@inheritDoc} */
    @Override
    public Header getHeader() {
        return header;
    }

    /** {@inheritDoc} */
    @Override
    public void reset(final FileFormat fileFormat) {
        header                    = new Header(3.0);
        segments                  = new ArrayList<>();
        metadata                  = null;
        context                   = null;
        stateVectorBlock          = null;
        keplerianElementsBlock    = null;
        spacecraftParametersBlock = null;
        covarianceBlock           = null;
        currentManeuver           = null;
        maneuverBlocks            = new ArrayList<>();
        userDefinedBlock          = null;
        if (fileFormat == FileFormat.XML) {
            structureProcessor = new XmlStructureProcessingState(Opm.ROOT, this);
            reset(fileFormat, structureProcessor);
        } else {
            structureProcessor = new ErrorState(); // should never be called
            reset(fileFormat, new HeaderProcessingState(this));
        }
    }

    /** {@inheritDoc} */
    @Override
    public boolean prepareHeader() {
        anticipateNext(new HeaderProcessingState(this));
        return true;
    }

    /** {@inheritDoc} */
    @Override
    public boolean inHeader() {
        anticipateNext(getFileFormat() == FileFormat.XML ? structureProcessor : this::processMetadataToken);
        return true;
    }

    /** {@inheritDoc} */
    @Override
    public boolean finalizeHeader() {
        header.validate(header.getFormatVersion());
        return true;
    }

    /** {@inheritDoc} */
    @Override
    public boolean prepareMetadata() {
        if (metadata != null) {
            return false;
        }
        metadata  = new CommonMetadata();
        context   = new ContextBinding(this::getConventions, this::isSimpleEOP,
                                       this::getDataContext, this::getParsedUnitsBehavior,
                                       this::getMissionReferenceDate,
                                       metadata::getTimeSystem, () -> 0.0, () -> 1.0);
        anticipateNext(this::processMetadataToken);
        return true;
    }

    /** {@inheritDoc} */
    @Override
    public boolean inMetadata() {
        anticipateNext(getFileFormat() == FileFormat.XML ? structureProcessor : this::processStateVectorToken);
        return true;
    }

    /** {@inheritDoc} */
    @Override
    public boolean finalizeMetadata() {
        metadata.finalizeMetadata(context);
        metadata.validate(header.getFormatVersion());
        if (metadata.getCenter().getBody() != null) {
            setMuCreated(metadata.getCenter().getBody().getGM());
        }
        return true;
    }

    /** {@inheritDoc} */
    @Override
    public boolean prepareData() {
        anticipateNext(getFileFormat() == FileFormat.XML ? this::processXmlSubStructureToken : this::processStateVectorToken);
        return true;
    }

    /** {@inheritDoc} */
    @Override
    public boolean inData() {
        return true;
    }

    /** {@inheritDoc} */
    @Override
    public boolean finalizeData() {
        if (metadata != null) {
            if (userDefinedBlock != null && userDefinedBlock.getParameters().isEmpty()) {
                userDefinedBlock = null;
            }
            if (keplerianElementsBlock != null) {
                keplerianElementsBlock.setEpoch(stateVectorBlock.getEpoch());
                if (Double.isNaN(keplerianElementsBlock.getMu())) {
                    keplerianElementsBlock.setMu(getSelectedMu());
                } else {
                    setMuParsed(keplerianElementsBlock.getMu());
                }
            }
            final double  mass = spacecraftParametersBlock == null ?
                                 defaultMass : spacecraftParametersBlock.getMass();
            final OpmData data = new OpmData(stateVectorBlock, keplerianElementsBlock,
                                             spacecraftParametersBlock, covarianceBlock,
                                             maneuverBlocks, userDefinedBlock,
                                             mass);
            data.validate(header.getFormatVersion());
            segments.add(new Segment<>(metadata, data));
        }
        metadata                  = null;
        context                   = null;
        stateVectorBlock          = null;
        keplerianElementsBlock    = null;
        spacecraftParametersBlock = null;
        covarianceBlock           = null;
        currentManeuver           = null;
        maneuverBlocks            = null;
        userDefinedBlock          = null;
        return true;
    }

    /** {@inheritDoc} */
    @Override
    public Opm build() {
        // OPM KVN file lack a DATA_STOP keyword, hence we can't call finalizeData()
        // automatically before the end of the file
        finalizeData();
        return new Opm(header, segments, getConventions(), getDataContext(), getSelectedMu());
    }

    /** Manage state vector section.
     * @param starting if true, parser is entering the section
     * otherwise it is leaving the section
     * @return always return true
     */
    boolean manageStateVectorSection(final boolean starting) {
        anticipateNext(starting ? this::processStateVectorToken : structureProcessor);
        return true;
    }

    /** Manage Keplerian elements section.
     * @param starting if true, parser is entering the section
     * otherwise it is leaving the section
     * @return always return true
     */
    boolean manageKeplerianElementsSection(final boolean starting) {
        anticipateNext(starting ? this::processKeplerianElementsToken : structureProcessor);
        return true;
    }

    /** Manage spacecraft parameters section.
     * @param starting if true, parser is entering the section
     * otherwise it is leaving the section
     * @return always return true
     */
    boolean manageSpacecraftParametersSection(final boolean starting) {
        anticipateNext(starting ? this::processSpacecraftParametersToken : structureProcessor);
        return true;
    }

    /** Manage covariance matrix section.
     * @param starting if true, parser is entering the section
     * otherwise it is leaving the section
     * @return always return true
     */
    boolean manageCovarianceSection(final boolean starting) {
        anticipateNext(starting ? this::processCovarianceToken : structureProcessor);
        return true;
    }

    /** Manage maneuvers section.
     * @param starting if true, parser is entering the section
     * otherwise it is leaving the section
     * @return always return true
     */
    boolean manageManeuversSection(final boolean starting) {
        anticipateNext(starting ? this::processManeuverToken : structureProcessor);
        return true;
    }

    /** Manage user-defined parameters section.
     * @param starting if true, parser is entering the section
     * otherwise it is leaving the section
     * @return always return true
     */
    boolean manageUserDefinedParametersSection(final boolean starting) {
        anticipateNext(starting ? this::processUserDefinedToken : structureProcessor);
        return true;
    }

    /** Process one metadata token.
     * @param token token to process
     * @return true if token was processed, false otherwise
     */
    private boolean processMetadataToken(final ParseToken token) {
        if (metadata == null) {
            // OPM KVN file lack a META_START keyword, hence we can't call prepareMetadata()
            // automatically before the first metadata token arrives
            prepareMetadata();
        }
        inMetadata();
        try {
            return token.getName() != null &&
                   MetadataKey.valueOf(token.getName()).process(token, context, metadata);
        } catch (IllegalArgumentException iaeM) {
            try {
                return OdmMetadataKey.valueOf(token.getName()).process(token, context, metadata);
            } catch (IllegalArgumentException iaeD) {
                try {
                    return CommonMetadataKey.valueOf(token.getName()).process(token, context, metadata);
                } catch (IllegalArgumentException iaeC) {
                    // token has not been recognized
                    return false;
                }
            }
        }
    }

    /** Process one XML data substructure token.
     * @param token token to process
     * @return true if token was processed, false otherwise
     */
    private boolean processXmlSubStructureToken(final ParseToken token) {
        try {
            return token.getName() != null &&
                   XmlSubStructureKey.valueOf(token.getName()).process(token, this);
        } catch (IllegalArgumentException iae) {
            // token has not been recognized
            return false;
        }
    }

    /** Process one state vector data token.
     * @param token token to process
     * @return true if token was processed, false otherwise
     */
    private boolean processStateVectorToken(final ParseToken token) {
        if (stateVectorBlock == null) {
            // OPM KVN file lack a META_STOP keyword, hence we can't call finalizeMetadata()
            // automatically before the first data token arrives
            finalizeMetadata();
            // OPM KVN file lack a DATA_START keyword, hence we can't call prepareData()
            // automatically before the first data token arrives
            prepareData();
            stateVectorBlock = new StateVector();
        }
        anticipateNext(getFileFormat() == FileFormat.XML ? this::processXmlSubStructureToken : this::processKeplerianElementsToken);
        try {
            return token.getName() != null &&
                   StateVectorKey.valueOf(token.getName()).process(token, context, stateVectorBlock);
        } catch (IllegalArgumentException iae) {
            // token has not been recognized
            return false;
        }
    }

    /** Process one Keplerian elements data token.
     * @param token token to process
     * @return true if token was processed, false otherwise
     */
    private boolean processKeplerianElementsToken(final ParseToken token) {
        if (keplerianElementsBlock == null) {
            keplerianElementsBlock = new KeplerianElements();
        }
        anticipateNext(getFileFormat() == FileFormat.XML ? this::processXmlSubStructureToken : this::processSpacecraftParametersToken);
        try {
            return token.getName() != null &&
                   KeplerianElementsKey.valueOf(token.getName()).process(token, context, keplerianElementsBlock);
        } catch (IllegalArgumentException iae) {
            // token has not been recognized
            return false;
        }
    }

    /** Process one spacecraft parameters data token.
     * @param token token to process
     * @return true if token was processed, false otherwise
     */
    private boolean processSpacecraftParametersToken(final ParseToken token) {
        if (spacecraftParametersBlock == null) {
            spacecraftParametersBlock = new SpacecraftParameters();
            if (moveCommentsIfEmpty(keplerianElementsBlock, spacecraftParametersBlock)) {
                // get rid of the empty logical block
                keplerianElementsBlock = null;
            }
        }
        anticipateNext(getFileFormat() == FileFormat.XML ? this::processXmlSubStructureToken : this::processCovarianceToken);
        try {
            return token.getName() != null &&
                   SpacecraftParametersKey.valueOf(token.getName()).process(token, context, spacecraftParametersBlock);
        } catch (IllegalArgumentException iae) {
            // token has not been recognized
            return false;
        }
    }

    /** Process one covariance matrix data token.
     * @param token token to process
     * @return true if token was processed, false otherwise
     */
    private boolean processCovarianceToken(final ParseToken token) {
        if (covarianceBlock == null) {
            // save the current metadata for later retrieval of reference frame
            final CommonMetadata savedMetadata = metadata;
            covarianceBlock = new CartesianCovariance(() -> savedMetadata.getReferenceFrame());
            if (moveCommentsIfEmpty(spacecraftParametersBlock, covarianceBlock)) {
                // get rid of the empty logical block
                spacecraftParametersBlock = null;
            }
        }
        anticipateNext(getFileFormat() == FileFormat.XML ? this::processXmlSubStructureToken : this::processManeuverToken);
        try {
            return token.getName() != null &&
                   CartesianCovarianceKey.valueOf(token.getName()).process(token, context, covarianceBlock);
        } catch (IllegalArgumentException iae) {
            // token has not been recognized
            return false;
        }
    }

    /** Process one maneuver data token.
     * @param token token to process
     * @return true if token was processed, false otherwise
     */
    private boolean processManeuverToken(final ParseToken token) {
        if (currentManeuver == null) {
            currentManeuver = new Maneuver();
            if (covarianceBlock != null && moveCommentsIfEmpty(covarianceBlock, currentManeuver)) {
                // get rid of the empty logical block
                covarianceBlock = null;
            }
        }
        anticipateNext(getFileFormat() == FileFormat.XML ? this::processXmlSubStructureToken : this::processUserDefinedToken);
        try {
            if (token.getName() != null &&
                ManeuverKey.valueOf(token.getName()).process(token, context, currentManeuver)) {
                // the token was processed properly
                if (currentManeuver.completed()) {
                    // current maneuver is completed
                    maneuverBlocks.add(currentManeuver);
                    currentManeuver = null;
                }
                return true;
            }
        } catch (IllegalArgumentException iae) {
            // ignored, delegate to next state below
        }
        // the token was not processed
        return false;
    }

    /** Process one maneuver data token.
     * @param token token to process
     * @return true if token was processed, false otherwise
     */
    private boolean processUserDefinedToken(final ParseToken token) {
        if (userDefinedBlock == null) {
            userDefinedBlock = new UserDefined();
            if (moveCommentsIfEmpty(currentManeuver, userDefinedBlock)) {
                // get rid of the empty logical block
                currentManeuver = null;
            }
        }
        anticipateNext(getFileFormat() == FileFormat.XML ? this::processXmlSubStructureToken : new ErrorState());
        if (token.getName().startsWith(UserDefined.USER_DEFINED_PREFIX)) {
            if (token.getType() == TokenType.ENTRY) {
                userDefinedBlock.addEntry(token.getName().substring(UserDefined.USER_DEFINED_PREFIX.length()),
                                          token.getContentAsNormalizedString());
            }
            return true;
        } else {
            // the token was not processed
            return false;
        }
    }

    /** Move comments from one empty logical block to another logical block.
     * @param origin origin block
     * @param destination destination block
     * @return true if origin block was empty
     */
    private boolean moveCommentsIfEmpty(final CommentsContainer origin, final CommentsContainer destination) {
        if (origin != null && origin.acceptComments()) {
            // origin block is empty, move the existing comments
            for (final String comment : origin.getComments()) {
                destination.addComment(comment);
            }
            return true;
        } else {
            return false;
        }
    }

}