# Copyright 2019 The Android Open Source Project
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#      http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""Verifies camera will produce full black & full white images."""


import logging
import math
import os.path
import matplotlib
from matplotlib import pylab


from mobly import test_runner
import numpy as np

import its_base_test
import camera_properties_utils
import capture_request_utils
import image_processing_utils
import its_session_utils

_ANDROID10_API_LEVEL = 29
_CH_FULL_SCALE = 255
_CH_THRESH_BLACK = 6
_CH_THRESH_WHITE = _CH_FULL_SCALE - 6
_CH_ATOL_WHITE = 2
_COLOR_PLANES = ['R', 'G', 'B']
_NAME = os.path.splitext(os.path.basename(__file__))[0]
_PATCH_H = 0.1
_PATCH_W = 0.1
_PATCH_X = 0.5 - _PATCH_W/2
_PATCH_Y = 0.5 - _PATCH_H/2
_VGA_WIDTH, _VGA_HEIGHT = 640, 480


def do_img_capture(cam, s, e, fmt, latency, cap_name, name_with_log_path):
  """Do the image captures with the defined parameters.

  Args:
    cam: its_session open for camera
    s: sensitivity for request
    e: exposure in ns for request
    fmt: format of request
    latency: number of frames for sync latency of request
    cap_name: string to define the capture
    name_with_log_path: NAME with path for plot directory

  Returns:
    means values of center patch from capture
  """

  req = capture_request_utils.manual_capture_request(s, e)
  cap = its_session_utils.do_capture_with_latency(cam, req, latency, fmt)
  img = image_processing_utils.convert_capture_to_rgb_image(cap)
  image_processing_utils.write_image(
      img, f'{name_with_log_path}_{cap_name}.jpg')
  patch = image_processing_utils.get_image_patch(
      img, _PATCH_X, _PATCH_Y, _PATCH_W, _PATCH_H)
  means = image_processing_utils.compute_image_means(patch)
  means = [m * _CH_FULL_SCALE for m in means]
  logging.debug('%s pixel means: %s', cap_name, str(means))
  r_exp = cap['metadata']['android.sensor.exposureTime']
  r_iso = cap['metadata']['android.sensor.sensitivity']
  logging.debug('%s shot write values: sens = %d, exp time = %.4fms',
                cap_name, s, (e / 1000000.0))
  logging.debug('%s shot read values: sens = %d, exp time = %.4fms',
                cap_name, r_iso, (r_exp / 1000000.0))
  return means


class BlackWhiteTest(its_base_test.ItsBaseTest):
  """Test that device will prodoce full black + white images.
  """

  def test_black_white(self):
    r_means = []
    g_means = []
    b_means = []

    with its_session_utils.ItsSession(
        device_id=self.dut.serial,
        camera_id=self.camera_id,
        hidden_physical_id=self.hidden_physical_id) as cam:
      props = cam.get_camera_properties()
      props = cam.override_with_hidden_physical_camera_props(props)
      name_with_log_path = os.path.join(self.log_path, _NAME)

      # Check SKIP conditions
      camera_properties_utils.skip_unless(
          camera_properties_utils.manual_sensor(props))

      # Load chart for scene
      its_session_utils.load_scene(
          cam, props, self.scene, self.tablet,
          its_session_utils.CHART_DISTANCE_NO_SCALING)

      # Initialize params for requests
      latency = camera_properties_utils.sync_latency(props)
      fmt = {'format': 'yuv', 'width': _VGA_WIDTH, 'height': _VGA_HEIGHT}
      expt_range = props['android.sensor.info.exposureTimeRange']
      sens_range = props['android.sensor.info.sensitivityRange']

      # Take shot with very low ISO and exp time: expect it to be black
      s = sens_range[0]
      e = expt_range[0]
      black_means = do_img_capture(
          cam, s, e, fmt, latency, 'black', name_with_log_path)
      r_means.append(black_means[0])
      g_means.append(black_means[1])
      b_means.append(black_means[2])

      # Take shot with very high ISO and exp time: expect it to be white.
      s = sens_range[1]
      e = expt_range[1]
      white_means = do_img_capture(
          cam, s, e, fmt, latency, 'white', name_with_log_path)
      r_means.append(white_means[0])
      g_means.append(white_means[1])
      b_means.append(white_means[2])

      # Draw plot
      pylab.title('test_black_white')
      pylab.plot([0, 1], r_means, '-ro')
      pylab.plot([0, 1], g_means, '-go')
      pylab.plot([0, 1], b_means, '-bo')
      pylab.xlabel('Capture Number')
      pylab.ylabel('Output Values [0:255]')
      pylab.ylim([0, 255])
      matplotlib.pyplot.savefig(f'{name_with_log_path}_plot_means.png')

      # Assert blacks below CH_THRESH_BLACK
      for ch, mean in enumerate(black_means):
        if mean >= _CH_THRESH_BLACK:
          raise AssertionError(f'{_COLOR_PLANES[ch]} black: {mean:.1f}, '
                               f'THRESH: {_CH_THRESH_BLACK}')

      # Assert whites above CH_THRESH_WHITE
      for ch, mean in enumerate(white_means):
        if mean <= _CH_THRESH_WHITE:
          raise AssertionError(f'{_COLOR_PLANES[ch]} white: {mean:.1f}, '
                               f'THRESH: {_CH_THRESH_WHITE}')

      # Assert channels saturate evenly (was test_channel_saturation)
      first_api_level = its_session_utils.get_first_api_level(self.dut.serial)
      if first_api_level > _ANDROID10_API_LEVEL:
        if not math.isclose(
            np.amin(white_means), np.amax(white_means), abs_tol=_CH_ATOL_WHITE):
          raise AssertionError('channel saturation not equal! '
                               f'RGB: {white_means}, ATOL: {_CH_ATOL_WHITE}')

if __name__ == '__main__':
  test_runner.main()