TypeSvMessage.java

/* Copyright 2022-2025 Luc Maisonobe
 * 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.rinex.navigation;

import org.orekit.errors.OrekitInternalError;
import org.orekit.gnss.SatelliteSystem;
import org.orekit.propagation.analytical.gnss.data.NavigationMessage;
import org.orekit.utils.formatting.FastLongFormatter;

import java.io.IOException;

/** Container for data shared by several navigation messages.
 * @author Luc Maisonobe
 * @since 12.0
 */
public abstract class TypeSvMessage implements NavigationMessage {

    /** Formatter for identifier.
     * @since 14.0
     */
    private static final FastLongFormatter TWO_DIGITS = new FastLongFormatter(2, true);

    /** Satellite system. */
    private final SatelliteSystem system;

    /** Satellite number. */
    private final int prn;

    /** Navigation message type. */
    private final String type;

    /** Navigation message subtype. */
    private final String subType;

    /** Simple constructor.
     * @param system satellite system
     * @param prn satellite number
     * @param type navigation message type
     * @param subType navigation message subtype
     */
    protected TypeSvMessage(final SatelliteSystem system, final int prn,
                            final String type, final String subType) {
        this.system  = system;
        this.prn     = prn;
        this.type    = type;
        this.subType = subType;
    }

    /** Get the satellite system.
     * @return the system
     */
    public SatelliteSystem getSystem() {
        return system;
    }

    /** Get satellite number.
     * @return the prn
     */
    public int getPrn() {
        return prn;
    }

    /** Get the identifier.
     * @return identifier
     * @since 14.0
     */
    public String getIdentifier() {
        try {
            final StringBuilder sb = new StringBuilder();
            sb.append(system.getKey());
            TWO_DIGITS.appendTo(sb, prn);
            return sb.toString();
        } catch (IOException ioe) {
            // this should never happen
            throw new OrekitInternalError(ioe);
        }
    }

    /** {@inheritDoc} */
    @Override
    public String getNavigationMessageType() {
        return type;
    }

    /** {@inheritDoc} */
    @Override
    public String getNavigationMessageSubType() {
        return subType;
    }

}