/******************************************************************************
 *
 * Purpose:  Implementation of Prologue class. Parse the prologue of one
 *           repeat cycle and keep the interesting info.
 * Author:   Bas Retsios, retsios@itc.nl
 *
 ******************************************************************************
 * Copyright (c) 2004, ITC
 *
 * SPDX-License-Identifier: MIT
 ******************************************************************************/

#include "cpl_port.h"  // Must be first.

#include "prologue.h"

static int size_SatelliteStatus()
{
    int iSizePrimary = 1 + 4 + 1 + 1 + 4 + 4 + 1 + 1 + 4 + 4 + 1;

    int iSizeOrbitCoef = 4 + 4 + 8 * 8 + 8 * 8 + 8 * 8 + 8 * 8 + 8 * 8 + 8 * 8;
    int iSizeOrbit = 4 + 4 + 100 * iSizeOrbitCoef;
    int iSizeAttitudeCoef = 4 + 4 + 8 * 8 + 8 * 8 + 8 * 8;
    int iSizeAttitude = 4 + 4 + 8 + 100 * iSizeAttitudeCoef;
    int iSizeSpinRateatRCStart = 8;
    int iSizeUTCCorrelation = 4 + 4 + 4 * 4 * 3 + 8 + 8 + 8 + 8 + 8;

    int iTotalSize = iSizePrimary + iSizeOrbit + iSizeAttitude +
                     iSizeSpinRateatRCStart + iSizeUTCCorrelation;

    return iTotalSize;
}

static int size_ImageAcquisition()
{
    // up to  DHSSSynchSelection
    int iSize1 = 8 + 8 + 8 + 12 + 42 + 42 * 2 + 2 + 2 + 2 + 2 + 1;
    // up to RefocusingDirection
    int iSize2 = 42 * 2 + 42 + 42 * 2 + 42 * 2 + 42 * 2 + 27 * 2 + 15 * 2 +
                 6 * 2 + 1 + 2 + 1;
    // to end
    int iSize3 =
        2 + 1 + 2 + 4 + 2 + 2 + 2 + 1 + 4 + 1 + 4 + 4 + 1 + 1 + 2 + 2 + 2 + 2;

    int iTotalSize = iSize1 + iSize2 + iSize3;

    return iTotalSize;
}

static int size_CelestialEvents()
{
    int iSizeCelestialBodies = 2 + 2 + 4 + 4 +
                               3 * 100 * (2 + 2 + 8 * 8 + 8 * 8) +
                               100 * (20 * (2 + 2 + 2 + 8 * 8 + 8 * 8));

    int iSizeRelationToImage = 1 + 2 + 2 + 1 + 1 + 1;

    int iTotalSize = iSizeCelestialBodies + iSizeRelationToImage;

    return iTotalSize;
}

static int size_Correction()
{
    return 19229;
}

static double iReadDouble(std::ifstream &ifile)
{
    double rVal;
    ifile.read(reinterpret_cast<char *>(&rVal), 8);
    CPL_MSBPTR64(&rVal);
    return rVal;
}

static double iReadReal(std::ifstream &ifile)
{
    float fVal;
    ifile.read(reinterpret_cast<char *>(&fVal), 4);
    CPL_MSBPTR32(&fVal);
    return fVal;
}

static int iReadInt(std::ifstream &ifile)
{
    int iResult;
    ifile.read(reinterpret_cast<char *>(&iResult), 4);
    CPL_MSBPTR32(&iResult);
    return iResult;
}

static unsigned char iReadByte(std::ifstream &ifile)
{
    // will read 1 byte from the file
    char b;

    ifile.read(&b, 1);

    return b;
}

ReferenceGridRecord::ReferenceGridRecord(std::ifstream &ifile)
{
    NumberOfLines = iReadInt(ifile);
    NumberOfColumns = iReadInt(ifile);
    LineDirGridStep = iReadReal(ifile);
    ColumnDirGridStep = iReadReal(ifile);
    GridOrigin = iReadByte(ifile);
}

PlannedCoverageVIS_IRRecord::PlannedCoverageVIS_IRRecord(std::ifstream &ifile)
{
    SouthernLinePlanned = iReadInt(ifile);
    NorthernLinePlanned = iReadInt(ifile);
    EasternColumnPlanned = iReadInt(ifile);
    WesternColumnPlanned = iReadInt(ifile);
}

PlannedCoverageHRVRecord::PlannedCoverageHRVRecord(std::ifstream &ifile)
{
    LowerSouthLinePlanned = iReadInt(ifile);
    LowerNorthLinePlanned = iReadInt(ifile);
    LowerEastColumnPlanned = iReadInt(ifile);
    LowerWestColumnPlanned = iReadInt(ifile);
    UpperSouthLinePlanned = iReadInt(ifile);
    UpperNorthLinePlanned = iReadInt(ifile);
    UpperEastColumnPlanned = iReadInt(ifile);
    UpperWestColumnPlanned = iReadInt(ifile);
}

ImageDescriptionRecord::ImageDescriptionRecord(std::ifstream &ifile)
{
    TypeOfProjection = iReadByte(ifile);
    LongitudeOfSSP = iReadReal(ifile);
    ReferenceGridVIS_IR = new ReferenceGridRecord(ifile);
    ReferenceGridHRV = new ReferenceGridRecord(ifile);
    PlannedCoverageVIS_IR = new PlannedCoverageVIS_IRRecord(ifile);
    PlannedCoverageHRV = new PlannedCoverageHRVRecord(ifile);
    ImageProcDirection = iReadByte(ifile);
    PixelGenDirection = iReadByte(ifile);
    for (int i = 0; i < 12; ++i)
        PlannedChannelProcessing[i] = iReadByte(ifile);
}

ImageDescriptionRecord::~ImageDescriptionRecord()
{
    delete ReferenceGridVIS_IR;
    delete ReferenceGridHRV;
    delete PlannedCoverageVIS_IR;
    delete PlannedCoverageHRV;
}

RadiometricProcessingRecord::RadiometricProcessingRecord(std::ifstream &ifile)
{
    // skip a part that doesn't interest us
    unsigned char dummy[12];
    int i;
    for (i = 0; i < 6; ++i)
        ifile.read((char *)dummy, 12);

    for (i = 0; i < 12; ++i)
    {
        Cal_Slope[i] = iReadDouble(ifile);
        Cal_Offset[i] = iReadDouble(ifile);
    }
}

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

Prologue::Prologue() : m_idr(nullptr), m_rpr(nullptr)
{
}

Prologue::~Prologue()
{
    if (m_idr)
        delete m_idr;
    if (m_rpr)
        delete m_rpr;
}

void Prologue::read(std::ifstream &ifile)
{
    /*unsigned char version = */ iReadByte(ifile);

    int iSkipHeadersSize = size_SatelliteStatus() + size_ImageAcquisition() +
                           size_CelestialEvents() + size_Correction();

    ifile.seekg(iSkipHeadersSize, std::ios_base::cur);

    m_idr = new ImageDescriptionRecord(ifile);

    m_rpr = new RadiometricProcessingRecord(ifile);
    // TODO: file is not left at the end of the Radiometric Processing Record
}