from __future__ import division
from dxtbx.format.Format import Format
from dxtbx.format.FormatHDF5 import FormatHDF5

class FormatHDF5Dectris(FormatHDF5):
  """ This is a placeholder implementation only.  Open example dataset
      provided by Dectris Ltd, Jan 2013.  Read the first image only.
      Later replace this with a sweep-oriented implementation that
      reads the whole dataset."""
  @staticmethod
  def understand(image_file):
    return False
    try:
      tag = FormatHDF5Dectris.open_file(image_file, 'rb').read(8)
    except IOError,e:
      return False

    return tag == "\211HDF\r\n\032\n"

  def __init__(self, image_file):

    assert(self.understand(image_file))

    FormatHDF5.__init__(self, image_file)

  def _start(self):
    from iotbx.detectors.eiger import EIGERImage
    self.detectorbase = EIGERImage(self._image_file)
    self.detectorbase.readHeader()

  def _goniometer(self):

    return self._goniometer_factory.single_axis()

  def _detector(self):
    '''Return a model for a simple detector'''

    return self._detector_factory.simple(
        sensor = 'PAD',
        distance = self.detectorbase.distance,
        beam_centre = (self.detectorbase.beamx,
                       self.detectorbase.beamy),
        fast_direction = '+x',
        slow_direction = '-y',
        pixel_size = (self.detectorbase.pixel_size,
                      self.detectorbase.pixel_size),
        image_size = (self.detectorbase.size1,
                      self.detectorbase.size2),
        trusted_range = (-1, self.detectorbase.saturation),
        mask = [])  # a list of dead rectangles

  def _beam(self):
    '''Return a simple model for the beam.'''

    return self._beam_factory.simple(self.detectorbase.wavelength)

  def _scan(self):
    '''Replace this with true values later
       when HDF5 sweep support is implemented.'''

    return self._scan_factory.make_scan(
      image_range = (1,1),
      #dummy value--return to this later please
      exposure_time = 1,
      oscillation = (self.detectorbase.osc_start,
        self.detectorbase.osc_start + self.detectorbase.deltaphi),
      epochs = {1:0.} # Later get the true time values from HDF5 file
      )

  def get_num_images(self):
    return self.detectorbase.image_count()

  def get_goniometer(self, index=None):
    return Format.get_goniometer(self)

  def get_detector(self, index=None):
    return Format.get_detector(self)

  def get_beam(self, index=None):
    return Format.get_beam(self)

  def get_scan(self, index=None):
    return Format.get_scan(self)

  def get_raw_data(self, index=None):
    return Format.get_raw_data(self)

  def get_detectorbase(self, index=None):
    self.detectorbase.img_number = index
    return self.detectorbase

  def get_image_file(self, index=None):
    return self.detectorbase.get_data_link(index)

if __name__ == '__main__':

  import sys

  for arg in sys.argv[1:]:
    print FormatHDF5Dectris.understand(arg)