rsspice 0.1.0

//
// GENERATED FILE
//

use super::*;
use crate::SpiceContext;
use f2rust_std::*;

const NGRAVS: i32 = 3;
const NGRAVC: i32 = 8;
const WGS721: i32 = 1;
const WGS72: i32 = 2;
const WGS84: i32 = 3;
const P_RAD: i32 = 1;
const P_XKE: i32 = 2;
const P_MU: i32 = 3;
const P_TUMN: i32 = 4;
const P_J2: i32 = 5;
const P_J3: i32 = 6;
const P_J4: i32 = 7;
const P_J3J2: i32 = 8;
const K_J2: i32 = 1;
const K_J3: i32 = 2;
const K_J4: i32 = 3;
const K_KE: i32 = 4;
const K_QO: i32 = 5;
const K_SO: i32 = 6;
const K_ER: i32 = 7;
const K_AE: i32 = 8;
const NGEO: i32 = K_AE;
const AFSPC: i32 = 1;
const IMPRVD: i32 = 2;
const KNDT20: i32 = 1;
const KNDD60: i32 = 2;
const KBSTAR: i32 = 3;
const KINCL: i32 = 4;
const KNODE0: i32 = 5;
const KECC: i32 = 6;
const KOMEGA: i32 = 7;
const KMO: i32 = 8;
const KNO: i32 = 9;
const KEPOCH: i32 = 10;
const NELEMS: i32 = KEPOCH;

/// Evaluate "two-line" element data
///
/// Evaluate NORAD two-line element data for earth orbiting
/// spacecraft. This evaluator uses algorithms as described
/// in Vallado 2006 \[4].
///
/// This routine supersedes SPICELIB routines EV2LIN and DPSPCE.
///
/// # Brief I/O
///
/// ```text
///  VARIABLE  I/O  DESCRIPTION
///  --------  ---  --------------------------------------------------
///  ET         I   Epoch in seconds past ephemeris epoch J2000.
///  GEOPHS     I   Geophysical constants
///  ELEMS      I   Two-line element data
///  STATE      O   Evaluated state
/// ```
///
/// # Detailed Input
///
/// ```text
///  ET       is the epoch in seconds past ephemeris epoch J2000
///           at which a state should be produced from the
///           input elements.
///
///  GEOPHS   is a collection of 8 geophysical constants needed
///           for computing a state. The order of these
///           constants must be:
///
///              GEOPHS(1) = J2 gravitational harmonic for Earth.
///              GEOPHS(2) = J3 gravitational harmonic for Earth.
///              GEOPHS(3) = J4 gravitational harmonic for Earth.
///
///           These first three constants are dimensionless.
///
///              GEOPHS(4) = KE: Square root of the GM for Earth where
///                          GM is expressed in Earth radii cubed per
///                          minutes squared.
///
///              GEOPHS(5) = QO: High altitude bound for atmospheric
///                          model in km.
///
///              GEOPHS(6) = SO: Low altitude bound for atmospheric
///                          model in km.
///
///              GEOPHS(7) = RE: Equatorial radius of the earth in km.
///
///              GEOPHS(8) = AE: Distance units/earth radius
///                          (normally 1)
///
///           Below are currently recommended values for these
///           items:
///
///              J2 =    1.082616D-3
///              J3 =   -2.53881D-6
///              J4 =   -1.65597D-6
///
///           The next item is the square root of GM for the Earth
///           given in units of earth-radii**1.5/Minute
///
///              KE =    7.43669161D-2
///
///           The next two items define the top and bottom of the
///           atmospheric drag model used by the type 10 ephemeris
///           type. Don't adjust these unless you understand the full
///           implications of such changes.
///
///              QO =  120.0D0
///              SO =   78.0D0
///
///           The ER value is the equatorial radius in km of the Earth
///           as used by NORAD.
///
///              ER = 6378.135D0
///
///           The value of AE is the number of distance units per
///           Earth radii used by the NORAD state propagation
///           software. The value should be 1 unless you've got a very
///           good understanding of the NORAD routine SGP4 and the
///           affect of changing this value.
///
///              AE =    1.0D0
///
///  ELEMS    is an array containing two-line element data
///           as prescribed below. The elements NDD6O and BSTAR
///           must already be scaled by the proper exponent stored
///           in the two line elements set. Moreover, the
///           various items must be converted to the units shown
///           here.
///
///              ELEMS (  1 ) = NDT20 in radians/minute**2
///              ELEMS (  2 ) = NDD60 in radians/minute**3
///              ELEMS (  3 ) = BSTAR
///              ELEMS (  4 ) = INCL  in radians
///              ELEMS (  5 ) = NODE0 in radians
///              ELEMS (  6 ) = ECC
///              ELEMS (  7 ) = OMEGA in radians
///              ELEMS (  8 ) = M0    in radians
///              ELEMS (  9 ) = N0    in radians/minute
///              ELEMS ( 10 ) = EPOCH of the elements in seconds
///                             past ephemeris epoch J2000.
/// ```
///
/// # Detailed Output
///
/// ```text
///  STATE    is the state produced by evaluating the input elements
///           at the input epoch ET. Units are km and km/sec relative
///           to the TEME reference frame.
/// ```
///
/// # Parameters
///
/// ```text
///  AFSPC    set the SGP4 propagator to use the original
///           Space Track #3 GST algorithm as described in Hoots [1];
///           value defined in zzsgp4.inc.
/// ```
///
/// # Exceptions
///
/// ```text
///  1)  No checks are made on the reasonableness of the inputs.
///
///  2)  If a problem occurs when evaluating the elements, an
///      error is signaled by a routine in the call tree of this
///      routine.
/// ```
///
/// # Particulars
///
/// ```text
///  This routine evaluates any NORAD two-line element sets for
///  near-earth orbiting satellites using the algorithms described in
///  Vallado 2006 [4].
/// ```
///
/// # Examples
///
/// ```text
///  The numerical results shown for this example may differ across
///  platforms. The results depend on the SPICE kernels used as
///  input, the compiler and supporting libraries, and the machine
///  specific arithmetic implementation.
///
///  1) Suppose you have a set of two-line elements for the LUME 1
///     cubesat. This example shows how you can use this routine
///     together with the routine GETELM to propagate a state to an
///     epoch of interest.
///
///     Use the meta-kernel shown below to load the required SPICE
///     kernels.
///
///
///        KPL/MK
///
///        File name: evsgp4_ex1.tm
///
///        This meta-kernel is intended to support operation of SPICE
///        example programs. The kernels shown here should not be
///        assumed to contain adequate or correct versions of data
///        required by SPICE-based user applications.
///
///        In order for an application to use this meta-kernel, the
///        kernels referenced here must be present in the user's
///        current working directory.
///
///        The names and contents of the kernels referenced
///        by this meta-kernel are as follows:
///
///           File name           Contents
///           ---------           ------------------------------------
///           naif0012.tls        Leapseconds
///           geophysical.ker     geophysical constants for evaluation
///                               of two-line element sets.
///
///        The geophysical.ker is a PCK file that is provided with the
///        SPICE toolkit under the "/data" directory.
///
///        \begindata
///
///           KERNELS_TO_LOAD = ( 'naif0012.tls',
///                               'geophysical.ker'  )
///
///        \begintext
///
///        End of meta-kernel
///
///
///     Example code begins here.
///
///
///           PROGRAM EVSGP4_EX1
///           IMPLICIT NONE
///
///     C
///     C     Local parameters.
///     C
///           CHARACTER*(*)         TIMSTR
///           PARAMETER           ( TIMSTR = '2020-05-26 02:25:00' )
///
///           INTEGER               PNAMLN
///           PARAMETER           ( PNAMLN = 2  )
///
///           INTEGER               TLELLN
///           PARAMETER           ( TLELLN = 69 )
///
///     C
///     C     The LUME-1 cubesat is an Earth orbiting object; set
///     C     the center ID to the Earth ID.
///     C
///           INTEGER               CENTER
///           PARAMETER           ( CENTER  = 399     )
///
///     C
///     C     Local variables.
///     C
///           CHARACTER*(PNAMLN)    NOADPN ( 8  )
///           CHARACTER*(TLELLN)    TLE    ( 2  )
///
///           DOUBLE PRECISION      ELEMS  ( 10 )
///           DOUBLE PRECISION      EPOCH
///           DOUBLE PRECISION      ET
///           DOUBLE PRECISION      GEOPHS ( 8  )
///           DOUBLE PRECISION      STATE  ( 6  )
///
///           INTEGER               I
///           INTEGER               N
///
///     C
///     C     These are the variables that will hold the constants
///     C     required by EVSGP4. These constants are available from
///     C     the loaded PCK file, which provides the actual values
///     C     and units as used by NORAD propagation model.
///     C
///     C     Constant   Meaning
///     C     --------   ------------------------------------------
///     C     J2         J2 gravitational harmonic for Earth.
///     C     J3         J3 gravitational harmonic for Earth.
///     C     J4         J4 gravitational harmonic for Earth.
///     C     KE         Square root of the GM for Earth.
///     C     QO         High altitude bound for atmospheric model.
///     C     SO         Low altitude bound for atmospheric model.
///     C     ER         Equatorial radius of the Earth.
///     C     AE         Distance units/earth radius.
///     C
///           DATA          NOADPN  /  'J2', 'J3', 'J4', 'KE',
///          .                         'QO', 'SO', 'ER', 'AE'  /
///
///     C
///     C     Define the Two-Line Element set for LUME-1.
///     C
///           TLE(1)  = '1 43908U 18111AJ  20146.60805006  .00000806'
///          .      //                   '  00000-0  34965-4 0  9999'
///           TLE(2)  = '2 43908  97.2676  47.2136 0020001 220.6050 '
///          .      //                   '139.3698 15.24999521 78544'
///
///     C
///     C     Load the MK file that includes the PCK file that provides
///     C     the geophysical constants required for the evaluation of
///     C     the two-line elements sets and the LSK, as it is required
///     C     by GETELM to perform time conversions.
///     C
///           CALL FURNSH ( 'evsgp4_ex1.tm' )
///
///     C
///     C     Retrieve the data from the kernel, and place it on
///     C     the GEOPHS array.
///     C
///           DO I = 1, 8
///              CALL BODVCD ( CENTER, NOADPN(I), 1, N, GEOPHS(I) )
///           END DO
///
///     C
///     C     Convert the Two Line Elements lines to the element sets.
///     C     Set the lower bound for the years to be the beginning
///     C     of the space age.
///     C
///           CALL GETELM ( 1957, TLE, EPOCH, ELEMS )
///
///     C
///     C     Now propagate the state using EVSGP4 to the epoch of
///     C     interest.
///     C
///           CALL STR2ET ( TIMSTR, ET )
///           CALL EVSGP4 ( ET, GEOPHS, ELEMS, STATE )
///
///     C
///     C     Display the results.
///     C
///           WRITE(*,'(2A)')       'Epoch   : ', TIMSTR
///           WRITE(*,'(A,3F16.8)') 'Position:', (STATE(I), I=1,3)
///           WRITE(*,'(A,3F16.8)') 'Velocity:', (STATE(I), I=4,6)
///
///
///           END
///
///
///     When this program was executed on a PC/Linux/gfortran/64-bit
///     platform, the output was:
///
///
///     Epoch   : 2020-05-26 02:25:00
///     Position:  -4644.60403398  -5038.95025539   -337.27141116
///     Velocity:     -0.45719025      0.92884817     -7.55917355
/// ```
///
/// # Literature References
///
/// ```text
///  [1]  F. Hoots and R. Roehrich, "Spacetrack Report #3: Models for
///       Propagation of the NORAD Element Sets," U.S. Air Force
///       Aerospace Defense Command, Colorado Springs, CO, 1980.
///
///  [2]  F. Hoots, "Spacetrack Report #6: Models for Propagation of
///       Space Command Element Sets,"  U.S. Air Force Aerospace
///       Defense Command, Colorado Springs, CO, 1986.
///
///  [3]  F. Hoots, P. Schumacher and R. Glover, "History of Analytical
///       Orbit Modeling in the U. S. Space Surveillance System,"
///       Journal of Guidance, Control, and Dynamics. 27(2):174-185,
///       2004.
///
///  [4]  D. Vallado, P. Crawford, R. Hujsak and T. Kelso, "Revisiting
///       Spacetrack Report #3," paper AIAA 2006-6753 presented at the
///       AIAA/AAS Astrodynamics Specialist Conference, Keystone, CO.,
///       August 21-24, 2006.
/// ```
///
/// # Author and Institution
///
/// ```text
///  M. Costa Sitja     (JPL)
///  E.D. Wright        (JPL)
/// ```
///
/// # Version
///
/// ```text
/// -    SPICELIB Version 1.0.0, 02-NOV-2021 (EDW) (MCS)
/// ```
pub fn evsgp4(
    ctx: &mut SpiceContext,
    et: f64,
    geophs: &[f64; 8],
    elems: &[f64; 10],
    state: &mut [f64; 6],
) -> crate::Result<()> {
    EVSGP4(et, geophs, elems, state, ctx.raw_context())?;
    ctx.handle_errors()?;
    Ok(())
}

//$Procedure EVSGP4 ( Evaluate "two-line" element data )
pub fn EVSGP4(
    ET: f64,
    GEOPHS: &[f64],
    ELEMS: &[f64],
    STATE: &mut [f64],
    ctx: &mut Context,
) -> f2rust_std::Result<()> {
    let GEOPHS = DummyArray::new(GEOPHS, 1..=8);
    let ELEMS = DummyArray::new(ELEMS, 1..=10);
    let mut STATE = DummyArrayMut::new(STATE, 1..=6);
    let mut T1: f64 = 0.0;

    //
    // Standard SPICE error handling.
    //
    if RETURN(ctx) {
        return Ok(());
    }

    CHKIN(b"EVSGP4", ctx)?;

    //
    // Evaluate TLE.
    //

    //
    // Initialize.
    //
    XXSGP4I(GEOPHS.as_slice(), ELEMS.as_slice(), AFSPC, ctx)?;

    if FAILED(ctx) {
        CHKOUT(b"EVSGP4", ctx)?;
        return Ok(());
    }

    //
    // Calculate time from epoch in minutes.
    //
    T1 = ELEMS[KEPOCH];
    T1 = ((ET - T1) / 60.0);

    //
    // Compute state.
    //
    XXSGP4E(T1, STATE.as_slice_mut(), ctx)?;

    if FAILED(ctx) {
        CHKOUT(b"EVSGP4", ctx)?;
        return Ok(());
    }

    //
    // Checkout, then return.
    //
    CHKOUT(b"EVSGP4", ctx)?;
    Ok(())
}