/*
 * The Python Imaging Library.
 *
 * the imaging library bindings
 *
 * history:
 * 1995-09-24 fl   Created
 * 1996-03-24 fl   Ready for first public release (release 0.0)
 * 1996-03-25 fl   Added fromstring (for Jack's "img" library)
 * 1996-03-28 fl   Added channel operations
 * 1996-03-31 fl   Added point operation
 * 1996-04-08 fl   Added new/new_block/new_array factories
 * 1996-04-13 fl   Added decoders
 * 1996-05-04 fl   Added palette hack
 * 1996-05-12 fl   Compile cleanly as C++
 * 1996-05-19 fl   Added matrix conversions, gradient fills
 * 1996-05-27 fl   Added display_mode
 * 1996-07-22 fl   Added getbbox, offset
 * 1996-07-23 fl   Added sequence semantics
 * 1996-08-13 fl   Added logical operators, point mode
 * 1996-08-16 fl   Modified paste interface
 * 1996-09-06 fl   Added putdata methods, use abstract interface
 * 1996-11-01 fl   Added xbm encoder
 * 1996-11-04 fl   Added experimental path stuff, draw_lines, etc
 * 1996-12-10 fl   Added zip decoder, crc32 interface
 * 1996-12-14 fl   Added modulo arithmetics
 * 1996-12-29 fl   Added zip encoder
 * 1997-01-03 fl   Added fli and msp decoders
 * 1997-01-04 fl   Added experimental sun_rle and tga_rle decoders
 * 1997-01-05 fl   Added gif encoder, getpalette hack
 * 1997-02-23 fl   Added histogram mask
 * 1997-05-12 fl   Minor tweaks to match the IFUNC95 interface
 * 1997-05-21 fl   Added noise generator, spread effect
 * 1997-06-05 fl   Added mandelbrot generator
 * 1997-08-02 fl   Modified putpalette to coerce image mode if necessary
 * 1998-01-11 fl   Added INT32 support
 * 1998-01-22 fl   Fixed draw_points to draw the last point too
 * 1998-06-28 fl   Added getpixel, getink, draw_ink
 * 1998-07-12 fl   Added getextrema
 * 1998-07-17 fl   Added point conversion to arbitrary formats
 * 1998-09-21 fl   Added support for resampling filters
 * 1998-09-22 fl   Added support for quad transform
 * 1998-12-29 fl   Added support for arcs, chords, and pieslices
 * 1999-01-10 fl   Added some experimental arrow graphics stuff
 * 1999-02-06 fl   Added draw_bitmap, font acceleration stuff
 * 2001-04-17 fl   Fixed some egcs compiler nits
 * 2001-09-17 fl   Added screen grab primitives (win32)
 * 2002-03-09 fl   Added stretch primitive
 * 2002-03-10 fl   Fixed filter handling in rotate
 * 2002-06-06 fl   Added I, F, and RGB support to putdata
 * 2002-06-08 fl   Added rankfilter
 * 2002-06-09 fl   Added support for user-defined filter kernels
 * 2002-11-19 fl   Added clipboard grab primitives (win32)
 * 2002-12-11 fl   Added draw context
 * 2003-04-26 fl   Tweaks for Python 2.3 beta 1
 * 2003-05-21 fl   Added createwindow primitive (win32)
 * 2003-09-13 fl   Added thread section hooks
 * 2003-09-15 fl   Added expand helper
 * 2003-09-26 fl   Added experimental LA support
 * 2004-02-21 fl   Handle zero-size images in quantize
 * 2004-06-05 fl   Added ptr attribute (used to access Imaging objects)
 * 2004-06-05 fl   Don't crash when fetching pixels from zero-wide images
 * 2004-09-17 fl   Added getcolors
 * 2004-10-04 fl   Added modefilter
 * 2005-10-02 fl   Added access proxy
 * 2006-06-18 fl   Always draw last point in polyline
 *
 * Copyright (c) 1997-2006 by Secret Labs AB
 * Copyright (c) 1995-2006 by Fredrik Lundh
 *
 * See the README file for information on usage and redistribution.
 */

#include "Python.h"

#ifdef HAVE_LIBZ
#include "zlib.h"
#endif

#include "Imaging.h"

#include "py3.h"

/* Configuration stuff. Feel free to undef things you don't need. */
#define WITH_IMAGECHOPS /* ImageChops support */
#define WITH_IMAGEDRAW /* ImageDraw support */
#define WITH_MAPPING /* use memory mapping to read some file formats */
#define WITH_IMAGEPATH /* ImagePath stuff */
#define WITH_ARROW /* arrow graphics stuff (experimental) */
#define WITH_EFFECTS /* special effects */
#define WITH_QUANTIZE /* quantization support */
#define WITH_RANKFILTER /* rank filter */
#define WITH_MODEFILTER /* mode filter */
#define WITH_THREADING /* "friendly" threading support */
#define WITH_UNSHARPMASK /* Kevin Cazabon's unsharpmask module */

#undef    VERBOSE

#define B16(p, i) ((((int)p[(i)]) << 8) + p[(i)+1])
#define L16(p, i) ((((int)p[(i)+1]) << 8) + p[(i)])
#define S16(v) ((v) < 32768 ? (v) : ((v) - 65536))

/* -------------------------------------------------------------------- */
/* OBJECT ADMINISTRATION                        */
/* -------------------------------------------------------------------- */

typedef struct {
    PyObject_HEAD
    Imaging image;
    ImagingAccess access;
} ImagingObject;

static PyTypeObject Imaging_Type;

#ifdef WITH_IMAGEDRAW

typedef struct
{
    /* to write a character, cut out sxy from glyph data, place
       at current position plus dxy, and advance by (dx, dy) */
    int dx, dy;
    int dx0, dy0, dx1, dy1;
    int sx0, sy0, sx1, sy1;
} Glyph;

typedef struct {
    PyObject_HEAD
    ImagingObject* ref;
    Imaging bitmap;
    int ysize;
    int baseline;
    Glyph glyphs[256];
} ImagingFontObject;

static PyTypeObject ImagingFont_Type;

typedef struct {
    PyObject_HEAD
    ImagingObject* image;
    UINT8 ink[4];
    int blend;
} ImagingDrawObject;

static PyTypeObject ImagingDraw_Type;

#endif

typedef struct {
    PyObject_HEAD
    ImagingObject* image;
    int readonly;
} PixelAccessObject;

static PyTypeObject PixelAccess_Type;

PyObject*
PyImagingNew(Imaging imOut)
{
    ImagingObject* imagep;

    if (!imOut)
        return NULL;

    imagep = PyObject_New(ImagingObject, &Imaging_Type);
    if (imagep == NULL) {
        ImagingDelete(imOut);
        return NULL;
    }

#ifdef VERBOSE
    printf("imaging %p allocated\n", imagep);
#endif

    imagep->image = imOut;
    imagep->access = ImagingAccessNew(imOut);

    return (PyObject*) imagep;
}

static void
_dealloc(ImagingObject* imagep)
{

#ifdef VERBOSE
    printf("imaging %p deleted\n", imagep);
#endif

    if (imagep->access)
        ImagingAccessDelete(imagep->image, imagep->access);
    ImagingDelete(imagep->image);
    PyObject_Del(imagep);
}

#define PyImaging_Check(op) (Py_TYPE(op) == &Imaging_Type)

Imaging PyImaging_AsImaging(PyObject *op)
{
    if (!PyImaging_Check(op)) {
        PyErr_BadInternalCall();
        return NULL;
    }

    return ((ImagingObject *)op)->image;
}


/* -------------------------------------------------------------------- */
/* THREAD HANDLING                                                      */
/* -------------------------------------------------------------------- */

void ImagingSectionEnter(ImagingSectionCookie* cookie)
{
#ifdef WITH_THREADING
    *cookie = (PyThreadState *) PyEval_SaveThread();
#endif
}

void ImagingSectionLeave(ImagingSectionCookie* cookie)
{
#ifdef WITH_THREADING
    PyEval_RestoreThread((PyThreadState*) *cookie);
#endif
}

/* -------------------------------------------------------------------- */
/* BUFFER HANDLING                                                      */
/* -------------------------------------------------------------------- */
/* Python compatibility API */

int PyImaging_CheckBuffer(PyObject* buffer)
{
#if PY_VERSION_HEX >= 0x03000000
    return PyObject_CheckBuffer(buffer);
#else
    return PyObject_CheckBuffer(buffer) || PyObject_CheckReadBuffer(buffer);
#endif
}

int PyImaging_GetBuffer(PyObject* buffer, Py_buffer *view)
{
    /* must call check_buffer first! */
#if PY_VERSION_HEX >= 0x03000000
    return PyObject_GetBuffer(buffer, view, PyBUF_SIMPLE);
#else
    /* Use new buffer protocol if available
       (mmap doesn't support this in 2.7, go figure) */
    if (PyObject_CheckBuffer(buffer)) {
        int success = PyObject_GetBuffer(buffer, view, PyBUF_SIMPLE);
        if (!success) { return success; }
        PyErr_Clear();
    }

    /* Pretend we support the new protocol; PyBuffer_Release happily ignores
       calling bf_releasebuffer on objects that don't support it */
    view->buf = NULL;
    view->len = 0;
    view->readonly = 1;
    view->format = NULL;
    view->ndim = 0;
    view->shape = NULL;
    view->strides = NULL;
    view->suboffsets = NULL;
    view->itemsize = 0;
    view->internal = NULL;

    Py_INCREF(buffer);
    view->obj = buffer;

    return PyObject_AsReadBuffer(buffer, (void *) &view->buf, &view->len);
#endif
}

/* -------------------------------------------------------------------- */
/* EXCEPTION REROUTING                                                  */
/* -------------------------------------------------------------------- */

/* error messages */
static const char* must_be_sequence = "argument must be a sequence";
static const char* must_be_two_coordinates =
                     "coordinate list must contain exactly 2 coordinates";
static const char* wrong_mode = "unrecognized image mode";
static const char* wrong_raw_mode = "unrecognized raw mode";
static const char* outside_image = "image index out of range";
static const char* outside_palette = "palette index out of range";
static const char* wrong_palette_size = "invalid palette size";
static const char* no_palette = "image has no palette";
static const char* readonly = "image is readonly";
/* static const char* no_content = "image has no content"; */

void *
ImagingError_IOError(void)
{
    PyErr_SetString(PyExc_IOError, "error when accessing file");
    return NULL;
}

void *
ImagingError_MemoryError(void)
{
    return PyErr_NoMemory();
}

void *
ImagingError_Mismatch(void)
{
    PyErr_SetString(PyExc_ValueError, "images do not match");
    return NULL;
}

void *
ImagingError_ModeError(void)
{
    PyErr_SetString(PyExc_ValueError, "image has wrong mode");
    return NULL;
}

void *
ImagingError_ValueError(const char *message)
{
    PyErr_SetString(
        PyExc_ValueError,
        (message) ? (char*) message : "unrecognized argument value"
        );
    return NULL;
}

void
ImagingError_Clear(void)
{
    PyErr_Clear();
}

/* -------------------------------------------------------------------- */
/* HELPERS                                */
/* -------------------------------------------------------------------- */

static int
getbands(const char* mode)
{
    Imaging im;
    int bands;

    /* FIXME: add primitive to libImaging to avoid extra allocation */
    im = ImagingNew(mode, 0, 0);
    if (!im)