# Implementation of an ImageFormat class to read MarIP-format image

from __future__ import division

from dxtbx.format.Format import Format

class FormatMarIP(Format):
  '''An image reading class for MarIP-format images
  Positive identification:  first 140 bytes contain the string "mar research"
  '''

  @staticmethod
  def understand(image_file):
    try:
      tag = FormatMarIP.open_file(image_file, 'rb').read(140)
    except IOError:
      return False
    return tag.find("mar research")>0

  def __init__(self, image_file):
    '''Initialise the image structure from the given file.'''

    assert(self.understand(image_file))

    Format.__init__(self, image_file)

  def _start(self):
    '''Open the image file, read the image header, copy the key / value
    pairs into an internal dictionary self._header_dictionary along with
    the length of the header in bytes self._header_size.'''
    from iotbx.detectors.marIP import MARIPImage
    self.detectorbase = MARIPImage(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, which at the moment insists
    that the offsets and rotations are all 0.0.'''

    assert self.detectorbase.parameters["TWOTHETA"] == 0.0

    return self._detector_factory.simple(
        sensor = 'IMAGE_PLATE',
        distance = self.detectorbase.parameters["DISTANCE"],
        beam_centre = (self.detectorbase.parameters["BEAM_CENTER_X"],
                       self.detectorbase.parameters["BEAM_CENTER_Y"]),
        fast_direction = '+x',
        slow_direction = '-y',
        pixel_size = (self.detectorbase.parameters["PIXEL_SIZE"],
                      self.detectorbase.parameters["PIXEL_SIZE"]),
        image_size = (self.detectorbase.parameters["SIZE1"],
                      self.detectorbase.parameters["SIZE2"]),
        trusted_range = (0, self.detectorbase.parameters["CCD_IMAGE_SATURATION"]),
        mask = [])

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

    return self._beam_factory.simple(self.detectorbase.parameters["WAVELENGTH"])

  def _scan(self):
    '''Return the scan information for this image.'''

    return self._scan_factory.single(
      filename = self._image_file,
      format = "MARIP",
      exposure_times = self.detectorbase.adaptor.exposure_time(),
      osc_start = self.detectorbase.parameters["OSC_START"],
      osc_width = self.detectorbase.parameters["OSC_RANGE"],
      epoch = None)

if __name__ == '__main__':

  import sys

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