from pygiftiio import *

from ctypes import *

import numpy

# setup

image = GiftiImage()

# CTypes provides constructors for pointer-based types.  This is important

# to the initialization of the various members of the structs we need

# to write via the library.

image.version = c_char_p("version_string")

image.darray = POINTER(POINTER(GiftiDataArray))()

image.data = c_void_p(None)

image.numDA = c_int(0)

image.swapped = c_int(0)

image.compressed = c_int(0)

# type(im) = GiftiImage

# type(ver) = str

def set_version(im, ver):

    image.version = c_char_p(ver)

# type(im) = GiftiImage

# type(numDA) = int

def set_numDA(im, numDA):

    im.numDA = c_int(numDA)

# type(im) = GiftiImage

# type(md) = GiftiMetaData

def set_meta_data(im, md):

    im.meta = md

# type(im) = GiftiImage

# type(da) = GiftiDataArray

def add_data_array(im, da):

    cur_numda = im.numDA

    # Create a pointer to the new dataarray

    da_ptr = pointer(da.data)

    # Grab the pointer to the image's dataarrays

    ptr = image.darray

    # Create a new dataarray array pointer

    ar = (POINTER(GiftiDataArray)*(cur_numda+1))()

    # We need to cast the resulting pointer for use by C

    ar = cast(ar, POINTER(POINTER(GiftiDataArray)))

    # Copy all of the current da's to the new array.  This just copies the pointers!

    for i in xrange(num_da):

        ar[i] = im.darray[i]

    # Add the new data array to the image's data

    ar[num_da] = da_ptr

    # Reassign the pointer

    im.darray = ar

    # Tell the image it has an extra DA now

    cur_numda += 1

    im.numDA = c_int(cur_numda)

# type(da) = GiftiDataArray

# type(axis) = int

# type(val) = int

def set_da_dim(da, axis, val):

    # Simple setter.  However, the axis variable here is a

    # python array index (as the da dims is an array)

    # To properly assign the value, the val variable must

    # be usable by C, so we must form a c_int type.

    # This is true for all Setters.

    da.dims[axis] = c_int(val)

# type(filename) = string

# type(im) = GiftiImage

def write_image(filename, im):

    return gifti_write_image, im, filename, 1)