Source code for schrodinger.test.stu.outcomes.custom.perceptual_diff

"""
Contains the workup is `perceptual_diff`

@copyright: Schrodinger, LLC. All rights reserved.
"""

import os
import socket
import sys

from schrodinger.test.stu import common
from schrodinger.test.stu.outcomes.standard_workups import WorkupFailure
from schrodinger.utils import subprocess

logger = common.logger


def _get_perceptual_diff_loc():
    perceptualdiff = 'perceptualdiff'
    platform = sys.platform.lower()
    if platform.startswith('win'):
        platform = 'WIN32-x86'
        perceptualdiff += '.exe'
    elif 'darwin' in platform:
        platform = 'Darwin-x86_64'
    else:
        platform = 'Linux-x86_64'
    return os.path.join(os.environ['SCHRODINGER_LIB'], platform,
                        'perceptualdiff-1.1.1', perceptualdiff)


def perceptual_diff(std_image, test_image):
    """
    Run Perceptual Diff to compare a test image to a standard.

    The workup requires access to the shared installation of Perceptual Diff
    in /nfs/software/lib/<platform>/. It expects host-specific std images to
    be located in a subdirectory of the test named references/<hostname>/.
    For example, for the host pdx-desk-l03.schrodinger.com, refeerences are
    expected in stu_<testid>/references/pdx-desk-l03.schrodinger.com/.

    usage: custom.perceptual_diff.perceptual_diff(std_image, test_image)
    """
    test_image_full_path = os.path.join(os.getcwd(), test_image)
    std_image_full_path = os.path.join(os.getcwd(), 'references',
                                       socket.gethostname(), std_image)
    if not os.path.isfile(test_image_full_path):
        raise WorkupFailure('Could not find test file: '
                            '{}'.format(test_image_full_path))
    elif not os.path.isfile(std_image_full_path):
        raise WorkupFailure('Could not find reference file: '
                            '{}'.format(std_image_full_path))
    else:
        per_diff = _get_perceptual_diff_loc()
        per_diff_cmd = [per_diff, std_image_full_path, test_image_full_path]
        try:
            exit_code = subprocess.call(per_diff_cmd)
        except Exception as err:
            raise WorkupFailure('ERROR: Perceptual Diff failed '
                                'with error {}'.format(err))
        if exit_code == 0:
            return True
        else:
            raise WorkupFailure('Perceptual Diff comparison failed. {} does '
                                'not match {}'.format(std_image_full_path,
                                                      test_image_full_path))