#!/usr/bin/env python
# Sweep.py
#   Copyright (C) 2006 CCLRC, Graeme Winter
#
#   This code is distributed under the BSD license, a copy of which is
#   included in the root directory of this package.
#
# 15th June 2006
#
# A class to represent a sweep of frames collected under the same conditions.
# This pertains to the dataset object in the early phases of processing.
#
# Update history:
#
# 21/JUN/06 added imagename(i) method.
# 22/JUN/06 added storage of user provided details

import os
import sys
import copy
import time

if not os.environ.has_key('XIA2_ROOT'):
  raise RuntimeError, 'XIA2_ROOT not defined'
if not os.environ.has_key('XIA2CORE_ROOT'):
  raise RuntimeError, 'XIA2CORE_ROOT not defined'

if not os.environ['XIA2_ROOT'] in sys.path:
  sys.path.append(os.path.join(os.environ['XIA2_ROOT']))

from Experts.FindImages import image2template, find_matching_images, \
     template_directory_number2image, image2template_directory, \
     headers2sweeps, headers2sweep_ids

# image header reading functionality
from Wrappers.XIA.Diffdump import Diffdump

def SweepFactory(template, directory, beam = None):
  '''A factory which will return a list of sweep objects which match
  the input template and directory.'''

  sweeps = []

  from Schema import load_imagesets
  imagesets = load_imagesets(template, directory)

  for imageset in imagesets:
    scan = imageset.get_scan()
    if scan is not None:
      sweeps.append(
        Sweep(template, directory,
              imageset=imageset,
              id_image=scan.get_image_range()[0],
              beam=beam))

  return sweeps

class Sweep(object):
  '''A class to represent a single sweep of frames.'''

  def __init__(self,
               template,
               directory,
               imageset=None,
               id_image=None,
               beam=None):

    '''Initialise the sweep by inspecting the images. id_image
    defines the first image in this sweep, and hence the identity of
    the sweep of more than one are found which match.'''

    self._identity_attributes = ['_collect_start', '_collect_end',
                                 '_template', '_id_image']

    if not id_image is None:
      self._id_image = id_image
    else:
      self._id_image = -1

    # populate the attributes of this object

    self._template = template
    self._directory = directory

    # populate the rest of the structure
    self._images = []

    if imageset is not None:
      self._imageset = imageset
      image_range = imageset.get_scan().get_image_range()
      self._images = list(range(image_range[0], image_range[1]+1))

    # if the beam has been specified, then this will
    # override the headers
    self._beam_centre = beam

    self.update()

    return

  def get_template(self):
    return self._imageset.get_template()

  def get_directory(self):
    return os.path.split(self.get_template())[0]

  def get_imageset(self):
    return self._imageset

  def get_images(self):
    # check if any more images have appeared
    self.update()
    image_range = self._imageset.get_scan().get_image_range()
    return list(range(image_range[0], image_range[1]+1))

  def get_distance(self):
    return self._imageset.get_detector()[0].get_distance()

  def get_wavelength(self):
    return self._imageset.get_beam().get_wavelength()

  def get_beam_centre(self):
    detector = self._imageset.get_detector()
    beam = self._imageset.get_beam()
    return tuple(reversed(detector.get_ray_intersection(beam.get_s0())[1]))

  def imagename(self, number):
    '''Compute an image name from an image number.'''

    return template_directory_number2image(self._template,
                                           self._directory,
                                           number)

  def _read_headers(self):
    '''Get the image headers for all of the images - this is not designed
    to be called exernally.'''

    # FIXME 23/AUG/06 there needs to be a "fast" version of this
    # which will read the headers more quickly, or not bother
    # or something, so that the xia2find function will work
    # reasonably quickly in cases where there are large numbers of
    # images - caching isn't good enough in those circumstances!

    self._headers = { }

    t = time.time()

    for i in self._images:
      dd = Diffdump()
      image = self.imagename(i)
      dd.set_image(image)
      header = dd.readheader()
      self._headers[i] = header

    return

  def update(self):
    '''Check to see if any more frames have appeared - if they
    have update myself and reset.'''

    images = find_matching_images(self._template,
                                  self._directory)

    if len(images) > len(self._images):

      self._images = images

      from Schema import load_imagesets
      imagesets = load_imagesets(template, directory, use_cache=False)

      max_images = 0
      best_sweep = None
      for imageset in imagesets:
        scan = imageset.get_scan()
        if scan is None: continue
        if imageset.get_scan().get_num_images() > max_images:
          best_sweep = imageset

      self._imageset = best_sweep

    return

if __name__ == '__main__':

  if len(sys.argv) < 2:
    image = os.path.join(os.environ['XIA2_ROOT'],
                         'Data', 'Test', 'Images', '12287_1_E1_001.img')
  else:
    image = sys.argv[1]

  template, directory = image2template_directory(image)

  sl = SweepFactory(template, directory)

  for s in sl:

    t = s.get_collect()
    print 'Data collection took %s seconds' % (t[1] - t[0])
    print 'For a total of %s seconds of exposure' % \
          (s.get_exposure_time() * \
           len(s.get_images()))
    print 'Images: %d to %d' % (min(s.get_images()), max(s.get_images()))
    print 'Template: %s' % s.get_template()
    print ''