#!/usr/bin/env python
# Copyright 2016 The PDFium Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.

import functools
import multiprocessing
import optparse
import os
import re
import shutil
import subprocess
import sys

import common
import gold
import pngdiffer
import suppressor

class KeyboardInterruptError(Exception): pass

# Nomenclature:
#   x_root - "x"
#   x_filename - "x.ext"
#   x_path - "path/to/a/b/c/x.ext"
#   c_dir - "path/to/a/b/c"

def TestOneFileParallel(this, test_case):
  """Wrapper to call GenerateAndTest() and redirect output to stdout."""
  try:
    input_filename, source_dir = test_case
    result = this.GenerateAndTest(input_filename, source_dir);
    return (result, input_filename, source_dir)
  except KeyboardInterrupt:
    raise KeyboardInterruptError()


class TestRunner:
  def __init__(self, dirname):
    # Currently the only used directories are corpus, javascript, and pixel,
    # which all correspond directly to the type for the test being run. In the
    # future if there are tests that don't have this clean correspondence, then
    # an argument for the type will need to be added.
    self.test_dir = dirname
    self.test_type = dirname
    self.enforce_expected_images = False
    self.oneshot_renderer = False

  # GenerateAndTest returns a tuple <success, outputfiles> where
  # success is a boolean indicating whether the tests passed comparison
  # tests and outputfiles is a list tuples:
  #          (path_to_image, md5_hash_of_pixelbuffer)
  def GenerateAndTest(self, input_filename, source_dir):
    use_ahem = 'use_ahem' in source_dir

    input_root, _ = os.path.splitext(input_filename)
    expected_txt_path = os.path.join(source_dir, input_root + '_expected.txt')

    pdf_path = os.path.join(self.working_dir, input_root + '.pdf')

    # Remove any existing generated images from previous runs.
    actual_images = self.image_differ.GetActualFiles(input_filename, source_dir,
                                                     self.working_dir)
    for image in actual_images:
      if os.path.exists(image):
        os.remove(image)

    sys.stdout.flush()

    raised_exception = self.Generate(source_dir, input_filename, input_root,
                                     pdf_path)

    if raised_exception is not None:
      print 'FAILURE: %s; %s' % (input_filename, raised_exception)
      return False, []

    results = []
    if os.path.exists(expected_txt_path):
      raised_exception = self.TestText(input_root, expected_txt_path, pdf_path)
    else:
      raised_exception, results = self.TestPixel(input_root, pdf_path, use_ahem)

    if raised_exception is not None:
      print 'FAILURE: %s; %s' % (input_filename, raised_exception)
      return False, results

    if actual_images:
      if self.image_differ.HasDifferences(input_filename, source_dir,
                                          self.working_dir):
        self.RegenerateIfNeeded_(input_filename, source_dir)
        return False, results
    else:
      if (self.enforce_expected_images
          and not self.test_suppressor.IsImageDiffSuppressed(input_filename)):
        self.RegenerateIfNeeded_(input_filename, source_dir)
        print 'FAILURE: %s; Missing expected images' % input_filename
        return False, results

    return True, results

  def RegenerateIfNeeded_(self, input_filename, source_dir):
    if (not self.options.regenerate_expected
        or self.test_suppressor.IsResultSuppressed(input_filename)
        or self.test_suppressor.IsImageDiffSuppressed(input_filename)):
      return

    platform_only = (self.options.regenerate_expected == 'platform')
    self.image_differ.Regenerate(input_filename, source_dir,
                                 self.working_dir, platform_only)

  def Generate(self, source_dir, input_filename, input_root, pdf_path):
    original_path = os.path.join(source_dir, input_filename)
    input_path = os.path.join(source_dir, input_root + '.in')

    input_event_path = os.path.join(source_dir, input_root + '.evt')
    if os.path.exists(input_event_path):
      output_event_path = os.path.splitext(pdf_path)[0] + '.evt'
      shutil.copyfile(input_event_path, output_event_path)

    if not os.path.exists(input_path):
      if os.path.exists(original_path):
        shutil.copyfile(original_path, pdf_path)
      return None

    sys.stdout.flush()

    return common.RunCommand(
        [sys.executable, self.fixup_path, '--output-dir=' + self.working_dir,
            input_path])

  def TestText(self, input_root, expected_txt_path, pdf_path):
    txt_path = os.path.join(self.working_dir, input_root + '.txt')

    with open(txt_path, 'w') as outfile:
      cmd_to_run = [self.pdfium_test_path, '--send-events', pdf_path]
      subprocess.check_call(cmd_to_run, stdout=outfile)

    cmd = [sys.executable, self.text_diff_path, expected_txt_path, txt_path]
    return common.RunCommand(cmd)

  def TestPixel(self, input_root, pdf_path, use_ahem):
    cmd_to_run = [self.pdfium_test_path, '--send-events', '--png', '--md5']

    if self.oneshot_renderer:
      cmd_to_run.append('--render-oneshot')

    if use_ahem:
      cmd_to_run.append('--font-dir=%s' % self.font_dir)

    cmd_to_run.append(pdf_path)
    return common.RunCommandExtractHashedFiles(cmd_to_run)

  def HandleResult(self, input_filename, input_path, result):
    success, image_paths = result

    if image_paths:
      for img_path, md5_hash in image_paths:
        # The output filename without image extension becomes the test name.
        # For example, "/path/to/.../testing/corpus/example_005.pdf.0.png"
        # becomes "example_005.pdf.0".
        test_name = os.path.splitext(os.path.split(img_path)[1])[0]

        if not self.test_suppressor.IsResultSuppressed(input_filename):
          matched = self.gold_baseline.MatchLocalResult(test_name, md5_hash)
          if matched == gold.GoldBaseline.MISMATCH:
            print 'Skia Gold hash mismatch for test case: %s' % test_name
          elif matched ==  gold.GoldBaseline.NO_BASELINE:
            print 'No Skia Gold baseline found for test case: %s' % test_name

        if self.gold_results:
          self.gold_results.AddTestResult(test_name, md5_hash, img_path)

    if self.test_suppressor.IsResultSuppressed(input_filename):
      self.result_suppressed_cases.append(input_filename)
      if success:
        self.surprises.append(input_path)
    else:
      if not success:
        self.failures.append(input_path)

  def Run(self):
    parser = optparse.OptionParser()

    parser.add_option('--build-dir', default=os.path.join('out', 'Debug'),
                      help='relative path from the base source directory')

    parser.add_option('-j', default=multiprocessing.cpu_count(),
                      dest='num_workers', type='int',
                      help='run NUM_WORKERS jobs in parallel')

    parser.add_option('--gold_properties', default='', dest="gold_properties",
                      help='Key value pairs that are written to the top level '
                           'of the JSON file that is ingested by Gold.')

    parser.add_option('--gold_key', default='', dest="gold_key",
                      help='Key value pairs that are added to the "key" field '
                           'of the JSON file that is ingested by Gold.')

    parser.add_option('--gold_output_dir', default='', dest="gold_output_dir",
                      help='Path of where to write the JSON output to be '
                           'uploaded to Gold.')

    parser.add_option('--gold_ignore_hashes', default='',
                      dest="gold_ignore_hashes",
                      help='Path to a file with MD5 hashes we wish to ignore.')

    parser.add_option('--regenerate_expected', default='',
                      dest="regenerate_expected",
                      help='Regenerates expected images. Valid values are '
                           '"all" to regenerate all expected pngs, and '
                           '"platform" to regenerate only platform-specific '
                           'expected pngs.')

    parser.add_option('--ignore_errors', action="store_true",
                      dest="ignore_errors",
                      help='Prevents the return value from being non-zero '
                           'when image comparison fails.')

    self.options, self.args = parser.parse_args()

    if (self.options.regenerate_expected
        and self.options.regenerate_expected not in ['all', 'platform']) :
      print 'FAILURE: --regenerate_expected must be "all" or "platform"'
      return 1

    finder = common.DirectoryFinder(self.options.build_dir)
    self.fixup_path = finder.ScriptPath('fixup_pdf_template.py')
    self.text_diff_path = finder.ScriptPath('text_diff.py')
    self.font_dir = os.path.join(finder.TestingDir(), 'resources', 'fonts')

    self.source_dir = finder.TestingDir()
    if self.test_dir != 'corpus':
      test_dir = finder.TestingDir(os.path.join('resources', self.test_dir))
    else:
      test_dir = finder.TestingDir(self.test_dir)

    self.pdfium_test_path = finder.ExecutablePath('pdfium_test')
    if not os.path.exists(self.pdfium_test_path):
      print "FAILURE: Can't find test executable '%s'" % self.pdfium_test_path
      print 'Use --build-dir to specify its location.'
      return 1

    self.working_dir = finder.WorkingDir(os.path.join('testing', self.test_dir))
    if not os.path.exists(self.working_dir):
      os.makedirs(self.working_dir)

    self.feature_string = subprocess.check_output([self.pdfium_test_path,
                                                   '--show-config'])
    self.test_suppressor = suppressor.Suppressor(finder, self.feature_string)
    self.image_differ = pngdiffer.PNGDiffer(finder)

    self.gold_baseline = gold.GoldBaseline(self.options.gold_properties)

    walk_from_dir = finder.TestingDir(test_dir);

    self.test_cases = []
    self.execution_suppressed_cases = []
    input_file_re = re.compile('^.+[.](in|pdf)$')
    if self.args:
      for file_name in self.args:
        file_name.replace('.pdf', '.in')
        input_path = os.path.join(walk_from_dir, file_name)
        if not os.path.isfile(input_path):
          print "Can't find test file '%s'" % file_name
          return 1

        self.test_cases.append((os.path.basename(input_path),
                           os.path.dirname(input_path)))
    else:
      for file_dir, _, filename_list in os.walk(walk_from_dir):
        for input_filename in filename_list:
          if input_file_re.match(input_filename):
            input_path = os.path.join(file_dir, input_filename)
            if self.test_suppressor.IsExecutionSuppressed(input_path):
              self.execution_suppressed_cases.append(input_path)
            else:
              if os.path.isfile(input_path):
                self.test_cases.append((input_filename, file_dir))

    self.test_cases.sort()
    self.failures = []
    self.surprises = []
    self.result_suppressed_cases = []

    # Collect Gold results if an output directory was named.
    self.gold_results = None
    if self.options.gold_output_dir:
      self.gold_results = gold.GoldResults(self.test_type,
                                           self.options.gold_output_dir,
                                           self.options.gold_properties,
                                           self.options.gold_key,
                                           self.options.gold_ignore_hashes)

    if self.options.num_workers > 1 and len(self.test_cases) > 1:
      try:
        pool = multiprocessing.Pool(self.options.num_workers)
        worker_func = functools.partial(TestOneFileParallel, self)

        worker_results = pool.imap(worker_func, self.test_cases)
        for worker_result in worker_results:
          result, input_filename, source_dir = worker_result
          input_path = os.path.join(source_dir, input_filename)

          self.HandleResult(input_filename, input_path, result)

      except KeyboardInterrupt:
        pool.terminate()
      finally:
        pool.close()
        pool.join()
    else:
      for test_case in self.test_cases:
        input_filename, input_file_dir = test_case
        result = self.GenerateAndTest(input_filename, input_file_dir)
        self.HandleResult(input_filename,
                          os.path.join(input_file_dir, input_filename), result)

    if self.gold_results:
      self.gold_results.WriteResults()

    if self.surprises:
      self.surprises.sort()
      print '\n\nUnexpected Successes:'
      for surprise in self.surprises:
        print surprise

    if self.failures:
      self.failures.sort()
      print '\n\nSummary of Failures:'
      for failure in self.failures:
        print failure

    self._PrintSummary()

    if self.failures:
      if not self.options.ignore_errors:
        return 1

    return 0

  def _PrintSummary(self):
    number_test_cases = len(self.test_cases)
    number_failures = len(self.failures)
    number_suppressed = len(self.result_suppressed_cases)
    number_successes = number_test_cases - number_failures - number_suppressed
    number_surprises = len(self.surprises)
    print
    print 'Test cases executed: %d' % number_test_cases
    print '  Successes: %d' % number_successes
    print '  Suppressed: %d' % number_suppressed
    print '    Surprises: %d' % number_surprises
    print '  Failures: %d' % number_failures
    print
    print 'Test cases not executed: %d' % len(self.execution_suppressed_cases)

  def SetEnforceExpectedImages(self, new_value):
    """Set whether to enforce that each test case provide an expected image."""
    self.enforce_expected_images = new_value

  def SetOneShotRenderer(self, new_value):
    """Set whether to use the oneshot renderer. """
    self.oneshot_renderer = new_value