/******************************************************************************
 * $Id: _gdal_array.cpp 10433 2006-12-02 05:18:17Z hobu $
 *
 * Project:  GDAL Python Bindings
 * Purpose:  Declarations of entry points in source files other than that
 *           generated from gdal.i.
 * Author:   Frank Warmerdam, warmerda@home.com
 *
 ******************************************************************************
 * Copyright (c) 2000, Frank Warmerdam
 *
 * Permission is hereby granted, free of charge, to any person obtaining a
 * copy of this software and associated documentation files (the "Software"),
 * to deal in the Software without restriction, including without limitation
 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
 * and/or sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included
 * in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
 * DEALINGS IN THE SOFTWARE.
 ******************************************************************************
 */

#include "Python.h"

#include "gdal_priv.h"
#include "gdal_array.h"



static PyObject *GDALArrayError;


/************************************************************************/
/*                          GetArrayFilename()                          */
/************************************************************************/

PyObject* GetArrayFilename(PyObject *self, PyObject *args){
    GDALRegister_NUMPY();
    char      szString[128];
    
    PyObject  *psArray;


    if(!PyArg_ParseTuple(args,"O:GetArrayFilename",&psArray) ) {
        PyErr_SetString(GDALArrayError, "Unable to read in array!");
        return NULL;
        }

    
    /* I wish I had a safe way of checking the type */        
    sprintf( szString, "NUMPY:::%p", psArray );
    return Py_BuildValue( "s", szString );

}
 

/************************************************************************/
/*                          GDALRegister_NUMPY()                        */
/************************************************************************/
   
PyObject* GDALRegister_NUMPY(void)

{
    GDALDriver	*poDriver;

    if( GDALGetDriverByName( "NUMPY" ) == NULL )
    {
        poDriver = new GDALDriver();
        
        poDriver->SetDescription( "NUMPY" );
        poDriver->SetMetadataItem( GDAL_DMD_LONGNAME, 
                                   "Numeric Python Array" );
        
        poDriver->pfnOpen = NUMPYDataset::Open;

        GetGDALDriverManager()->RegisterDriver( poDriver );

    }
    Py_INCREF(Py_None);
    return Py_None;
}


/************************************************************************/
/*                          Initialization()                            */
/************************************************************************/

static PyMethodDef GDALPythonArrayMethods[] = {

    {"GDALRegister_NUMPY", (PyCFunction)GDALRegister_NUMPY, METH_VARARGS,
        "Registers the NUMPY driver"},        
    {"GetArrayFilename", (PyCFunction)GetArrayFilename, METH_VARARGS,
        "Returns filename hack for GDALOpen"},  
    {NULL, NULL, 0, NULL}
};

PyMODINIT_FUNC
init_gdal_array(void)
{
    PyObject* module;
    module = Py_InitModule3("_gdal_array", GDALPythonArrayMethods,
                       "GDAL numpy helper module");
    import_array();
    if (module == NULL)
      return;
    GDALArrayError = PyErr_NewException("_gdal_array.GDALArrayError", NULL, NULL);
    Py_INCREF(GDALArrayError);
    PyModule_AddObject(module, "GDALArrayError", GDALArrayError);
    

}

/************************************************************************/
/*                            NUMPYDataset()                            */
/************************************************************************/

NUMPYDataset::NUMPYDataset()

{
    pszProjection = CPLStrdup("");
    adfGeoTransform[0] = 0.0;
    adfGeoTransform[1] = 1.0;
    adfGeoTransform[2] = 0.0;
    adfGeoTransform[3] = 0.0;
    adfGeoTransform[4] = 0.0;
    adfGeoTransform[5] = 1.0;

    nGCPCount = 0;
    pasGCPList = NULL;
    pszGCPProjection = CPLStrdup("");
}

/************************************************************************/
/*                            ~NUMPYDataset()                            */
/************************************************************************/

NUMPYDataset::~NUMPYDataset()

{
    CPLFree( pszProjection );

    CPLFree( pszGCPProjection );
    if( nGCPCount > 0 )
    {
        GDALDeinitGCPs( nGCPCount, pasGCPList );
        CPLFree( pasGCPList );
    }

    FlushCache();
    Py_DECREF( psArray );
}

/************************************************************************/
/*                          GetProjectionRef()                          */
/************************************************************************/

const char *NUMPYDataset::GetProjectionRef()

{
    return( pszProjection );
}

/************************************************************************/
/*                           SetProjection()                            */
/************************************************************************/

CPLErr NUMPYDataset::SetProjection( const char * pszNewProjection )

{
    CPLFree( pszProjection );
    pszProjection = CPLStrdup( pszNewProjection );

    return CE_None;
}

/************************************************************************/
/*                          GetGeoTransform()                           */
/************************************************************************/

CPLErr NUMPYDataset::GetGeoTransform( double * padfTransform )

{
    memcpy( padfTransform, adfGeoTransform, sizeof(double)*6 );
    return CE_None;
}

/************************************************************************/
/*                          SetGeoTransform()                           */
/************************************************************************/

CPLErr NUMPYDataset::SetGeoTransform( double * padfTransform )

{
    memcpy( adfGeoTransform, padfTransform, sizeof(double)*6 );
    return( CE_None );
}

/************************************************************************/
/*                            GetGCPCount()                             */
/************************************************************************/

int NUMPYDataset::GetGCPCount()

{
    return nGCPCount;
}

/************************************************************************/
/*                          GetGCPProjection()                          */
/************************************************************************/

const char *NUMPYDataset::GetGCPProjection()

{
    return pszGCPProjection;
}

/************************************************************************/
/*                               GetGCPs()                              */
/************************************************************************/

const GDAL_GCP *NUMPYDataset::GetGCPs()

{
    return pasGCPList;
}

/************************************************************************/
/*                              SetGCPs()                               */
/************************************************************************/

CPLErr NUMPYDataset::SetGCPs( int nGCPCount, const GDAL_GCP *pasGCPList,
                              const char *pszGCPProjection )

{
    CPLFree( this->pszGCPProjection );
    if( this->nGCPCount > 0 )
    {
        GDALDeinitGCPs( this->nGCPCount, this->pasGCPList );
        CPLFree( this->pasGCPList );
    }

    this->pszGCPProjection = CPLStrdup(pszGCPProjection);

    this->nGCPCount = nGCPCount;

    this->pasGCPList = GDALDuplicateGCPs( nGCPCount, pasGCPList );

    return CE_None;
}

/************************************************************************/
/*                                Open()                                */
/************************************************************************/

GDALDataset *NUMPYDataset::Open( GDALOpenInfo * poOpenInfo )

{
    PyArrayObject *psArray;
    GDALDataType  eType;
    int     nBands;

/* -------------------------------------------------------------------- */
/*      Is this a numpy dataset name?                                   */
/* -------------------------------------------------------------------- */
    if( !EQUALN(poOpenInfo->pszFilename,"NUMPY:::",8) 
        || poOpenInfo->fp != NULL )
        return NULL;

    psArray = NULL;
    sscanf( poOpenInfo->pszFilename+8, "%p", &(psArray) );
    if( psArray == NULL )
    {
        CPLError( CE_Failure, CPLE_AppDefined, 
                  "Failed to parse meaningful pointer value from NUMPY name\n"
                  "string: %s\n", 
                  poOpenInfo->pszFilename );
        return NULL;
    }

/* -------------------------------------------------------------------- */
/*      If we likely have corrupt definitions of the NUMPY stuff,       */
/*      then warn now.                                                  */
/* -------------------------------------------------------------------- */
#ifdef NUMPY_DEFS_WRONG
    CPLError( CE_Warning, CPLE_AppDefined, 
              "It would appear you have built GDAL without having it use\n"
              "the Numeric python include files.  Old definitions have\n"
              "been used instead at build time, and it is quite possible that\n"
              "the things will shortly fail or crash if they are wrong.\n"
              "Consider installing Numeric, and rebuilding with HAVE_NUMPY\n"
              "enabled in gdal\nmake.opt." );
#endif

/* -------------------------------------------------------------------- */
/*      Is this a directly mappable Python array?  Verify rank, and     */
/*      data type.                                                      */
/* -------------------------------------------------------------------- */

    if( psArray->nd < 2 || psArray->nd > 3 )
    {
        CPLError( CE_Failure, CPLE_AppDefined, 
                  "Illegal numpy array rank %d.\n", 
                  psArray->nd );
        return NULL;
    }

    switch( psArray->descr->type_num )
    {
      case NPY_CDOUBLE:
        eType = GDT_CFloat64;
        break;

      case NPY_CFLOAT:
        eType = GDT_CFloat32;
        break;

      case NPY_DOUBLE:
        eType = GDT_Float64;
        break;

      case NPY_FLOAT:
        eType = GDT_Float32;
        break;

      case NPY_INT:
      case NPY_LONG:
        eType = GDT_Int32;
        break;

      case NPY_UINT:
      case NPY_ULONG:
        eType = GDT_UInt32;
        break;

      case NPY_SHORT:
        eType = GDT_Int16;
        break;

      case NPY_USHORT:
        eType = GDT_UInt16;
        break;

      case NPY_BYTE:
      case NPY_UBYTE:
        eType = GDT_Byte;
        break;

      default:
        CPLError( CE_Failure, CPLE_AppDefined, 
                  "Unable to access numpy arrays of typecode `%c'.\n", 
                  psArray->descr->type );
        return NULL;
    }

/* -------------------------------------------------------------------- */
/*      Create the new NUMPYDataset object.                             */
/* -------------------------------------------------------------------- */
    NUMPYDataset *poDS;

    poDS = new NUMPYDataset();

    poDS->psArray = psArray;

    poDS->eAccess = GA_ReadOnly;

/* -------------------------------------------------------------------- */
/*      Add a reference to the array.                                   */
/* -------------------------------------------------------------------- */
    Py_INCREF( psArray );

/* -------------------------------------------------------------------- */
/*      Workout the data layout.                                        */
/* -------------------------------------------------------------------- */
    int    nBandOffset;
    int    nPixelOffset;
    int    nLineOffset;

    if( psArray->nd == 3 )
    {
        nBands = psArray->dimensions[0];
        nBandOffset = psArray->strides[0];
        poDS->nRasterXSize = psArray->dimensions[2];
        nPixelOffset = psArray->strides[2];
        poDS->nRasterYSize = psArray->dimensions[1];
        nLineOffset = psArray->strides[1];
    }
    else
    {
        nBands = 1;
        nBandOffset = 0;
        poDS->nRasterXSize = psArray->dimensions[1];
        nPixelOffset = psArray->strides[1];
        poDS->nRasterYSize = psArray->dimensions[0];
        nLineOffset = psArray->strides[0];
    }

/* -------------------------------------------------------------------- */
/*      Create band information objects.                                */
/* -------------------------------------------------------------------- */
    for( int iBand = 0; iBand < nBands; iBand++ )
    {
        poDS->SetBand( iBand+1, 
                       (GDALRasterBand *) 
                       MEMCreateRasterBand( poDS, iBand+1, 
                                (GByte *) psArray->data + nBandOffset*iBand,
                                          eType, nPixelOffset, nLineOffset,
                                          FALSE ) );
    }

/* -------------------------------------------------------------------- */
/*      Try to return a regular handle on the file.                     */
/* -------------------------------------------------------------------- */
    return poDS;
}