# Copyright 2017 The TensorFlow Authors. All Rights Reserved.
#
# 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.
# ==============================================================================

"""A set of functions that are used for visualization.
These functions often receive an image, perform some visualization on the image.
The functions do not return a value, instead they modify the image itself.
"""
import abc
import collections
# Set headless-friendly backend.
# import matplotlib;

# matplotlib.use('Agg')  # pylint: disable=multiple-statements
# import matplotlib.pyplot as plt  # pylint: disable=g-import-not-at-top
import numpy as np
import PIL.Image as Image
import PIL.ImageColor as ImageColor
import PIL.ImageDraw as ImageDraw
import PIL.ImageFont as ImageFont
import six
from six.moves import range
from six.moves import zip
import tensorflow as tf

_TITLE_LEFT_MARGIN = 10
_TITLE_TOP_MARGIN = 10
STANDARD_COLORS = [
    'AliceBlue', 'Chartreuse', 'Aqua', 'Aquamarine', 'Azure', 'Beige', 'Bisque',
    'BlanchedAlmond', 'BlueViolet', 'BurlyWood', 'CadetBlue', 'AntiqueWhite',
    'Chocolate', 'Coral', 'CornflowerBlue', 'Cornsilk', 'Crimson', 'Cyan',
    'DarkCyan', 'DarkGoldenRod', 'DarkGrey', 'DarkKhaki', 'DarkOrange',
    'DarkOrchid', 'DarkSalmon', 'DarkSeaGreen', 'DarkTurquoise', 'DarkViolet',
    'DeepPink', 'DeepSkyBlue', 'DodgerBlue', 'FireBrick', 'FloralWhite',
    'ForestGreen', 'Fuchsia', 'Gainsboro', 'GhostWhite', 'Gold', 'GoldenRod',
    'Salmon', 'Tan', 'HoneyDew', 'HotPink', 'IndianRed', 'Ivory', 'Khaki',
    'Lavender', 'LavenderBlush', 'LawnGreen', 'LemonChiffon', 'LightBlue',
    'LightCoral', 'LightCyan', 'LightGoldenRodYellow', 'LightGray', 'LightGrey',
    'LightGreen', 'LightPink', 'LightSalmon', 'LightSeaGreen', 'LightSkyBlue',
    'LightSlateGray', 'LightSlateGrey', 'LightSteelBlue', 'LightYellow', 'Lime',
    'LimeGreen', 'Linen', 'Magenta', 'MediumAquaMarine', 'MediumOrchid',
    'MediumPurple', 'MediumSeaGreen', 'MediumSlateBlue', 'MediumSpringGreen',
    'MediumTurquoise', 'MediumVioletRed', 'MintCream', 'MistyRose', 'Moccasin',
    'NavajoWhite', 'OldLace', 'Olive', 'OliveDrab', 'Orange', 'OrangeRed',
    'Orchid', 'PaleGoldenRod', 'PaleGreen', 'PaleTurquoise', 'PaleVioletRed',
    'PapayaWhip', 'PeachPuff', 'Peru', 'Pink', 'Plum', 'PowderBlue', 'Purple',
    'Red', 'RosyBrown', 'RoyalBlue', 'SaddleBrown', 'Green', 'SandyBrown',
    'SeaGreen', 'SeaShell', 'Sienna', 'Silver', 'SkyBlue', 'SlateBlue',
    'SlateGray', 'SlateGrey', 'Snow', 'SpringGreen', 'SteelBlue', 'GreenYellow',
    'Teal', 'Thistle', 'Tomato', 'Turquoise', 'Violet', 'Wheat', 'White',
    'WhiteSmoke', 'Yellow', 'YellowGreen'
]


def _get_multiplier_for_color_randomness():
    """Returns a multiplier to get semi-random colors from successive indices.
  This function computes a prime number, p, in the range [2, 17] that:
  - is closest to len(STANDARD_COLORS) / 10
  - does not divide len(STANDARD_COLORS)
  If no prime numbers in that range satisfy the constraints, p is returned as 1.
  Once p is established, it can be used as a multiplier to select
  non-consecutive colors from STANDARD_COLORS:
  colors = [(p * i) % len(STANDARD_COLORS) for i in range(20)]
  """
    num_colors = len(STANDARD_COLORS)
    prime_candidates = [5, 7, 11, 13, 17]

    # Remove all prime candidates that divide the number of colors.
    prime_candidates = [p for p in prime_candidates if num_colors % p]
    if not prime_candidates:
        return 1

    # Return the closest prime number to num_colors / 10.
    abs_distance = [np.abs(num_colors / 10. - p) for p in prime_candidates]
    num_candidates = len(abs_distance)
    inds = [i for _, i in sorted(zip(abs_distance, range(num_candidates)))]
    return prime_candidates[inds[0]]


def draw_bounding_box_on_image_array(image,
                                     ymin,
                                     xmin,
                                     ymax,
                                     xmax,
                                     color='red',
                                     thickness=4,
                                     display_str_list=(),
                                     use_normalized_coordinates=True):
    """Adds a bounding box to an image (numpy array).
  Bounding box coordinates can be specified in either absolute (pixel) or
  normalized coordinates by setting the use_normalized_coordinates argument.
  Args:
    image: a numpy array with shape [height, width, 3].
    ymin: ymin of bounding box.
    xmin: xmin of bounding box.
    ymax: ymax of bounding box.
    xmax: xmax of bounding box.
    color: color to draw bounding box. Default is red.
    thickness: line thickness. Default value is 4.
    display_str_list: list of strings to display in box
                      (each to be shown on its own line).
    use_normalized_coordinates: If True (default), treat coordinates
      ymin, xmin, ymax, xmax as relative to the image.  Otherwise treat
      coordinates as absolute.
  """
    image_pil = Image.fromarray(np.uint8(image)).convert('RGB')
    draw_bounding_box_on_image(image_pil, ymin, xmin, ymax, xmax, color,
                               thickness, display_str_list,
                               use_normalized_coordinates)
    np.copyto(image, np.array(image_pil))


def draw_bounding_box_on_image(image,
                               ymin,
                               xmin,
                               ymax,
                               xmax,
                               color='red',
                               thickness=4,
                               display_str_list=(),
                               use_normalized_coordinates=True):
    """Adds a bounding box to an image.
  Bounding box coordinates can be specified in either absolute (pixel) or
  normalized coordinates by setting the use_normalized_coordinates argument.
  Each string in display_str_list is displayed on a separate line above the
  bounding box in black text on a rectangle filled with the input 'color'.
  If the top of the bounding box extends to the edge of the image, the strings
  are displayed below the bounding box.
  Args:
    image: a PIL.Image object.
    ymin: ymin of bounding box.
    xmin: xmin of bounding box.
    ymax: ymax of bounding box.
    xmax: xmax of bounding box.
    color: color to draw bounding box. Default is red.
    thickness: line thickness. Default value is 4.
    display_str_list: list of strings to display in box
                      (each to be shown on its own line).
    use_normalized_coordinates: If True (default), treat coordinates
      ymin, xmin, ymax, xmax as relative to the image.  Otherwise treat
      coordinates as absolute.
  """
    draw = ImageDraw.Draw(image)
    im_width, im_height = image.size
    if use_normalized_coordinates:
        (left, right, top, bottom) = (xmin * im_width, xmax * im_width,
                                      ymin * im_height, ymax * im_height)
    else:
        (left, right, top, bottom) = (xmin, xmax, ymin, ymax)
    if thickness > 0:
        draw.line([(left, top), (left, bottom), (right, bottom), (right, top),
                   (left, top)],
                  width=thickness,
                  fill=color)
    try:
        font = ImageFont.truetype('arial.ttf', 24)
    except IOError:
        font = ImageFont.load_default()

    # If the total height of the display strings added to the top of the bounding
    # box exceeds the top of the image, stack the strings below the bounding box
    # instead of above.
    display_str_heights = [font.getsize(ds)[1] for ds in display_str_list]
    # Each display_str has a top and bottom margin of 0.05x.
    total_display_str_height = (1 + 2 * 0.05) * sum(display_str_heights)

    if top > total_display_str_height:
        text_bottom = top
    else:
        text_bottom = bottom + total_display_str_height
    # Reverse list and print from bottom to top.
    for display_str in display_str_list[::-1]:
        text_width, text_height = font.getsize(display_str)
        margin = np.ceil(0.05 * text_height)
        draw.rectangle(
            [(left, text_bottom - text_height - 2 * margin), (left + text_width,
                                                              text_bottom)],
            fill=color)
        draw.text(
            (left + margin, text_bottom - text_height - margin),
            display_str,
            fill='black',
            font=font)
        text_bottom -= text_height - 2 * margin


def draw_keypoints_on_image_array(image,
                                  key_points,
                                  keypoint_scores=None,
                                  min_score_thresh=0.5,
                                  color='red',
                                  radius=2,
                                  use_normalized_coordinates=True,
                                  keypoint_edges=None,
                                  keypoint_edge_color='green',
                                  keypoint_edge_width=2):
    """Draws keypoints on an image (numpy array).
  Args:
    image: a numpy array with shape [height, width, 3].
    key_points: a numpy array with shape [num_keypoints, 2].
    keypoint_scores: a numpy array with shape [num_keypoints]. If provided, only
      those keypoints with a score above score_threshold will be visualized.
    min_score_thresh: A scalar indicating the minimum keypoint score required
      for a keypoint to be visualized. Note that keypoint_scores must be
      provided for this threshold to take effect.
    color: color to draw the keypoints with. Default is red.
    radius: keypoint radius. Default value is 2.
    use_normalized_coordinates: if True (default), treat keypoint values as
      relative to the image.  Otherwise treat them as absolute.
    keypoint_edges: A list of tuples with keypoint indices that specify which
      keypoints should be connected by an edge, e.g. [(0, 1), (2, 4)] draws
      edges from keypoint 0 to 1 and from keypoint 2 to 4.
    keypoint_edge_color: color to draw the keypoint edges with. Default is red.
    keypoint_edge_width: width of the edges drawn between keypoints. Default
      value is 2.
  """
    image_pil = Image.fromarray(np.uint8(image)).convert('RGB')
    draw_keypoints_on_image(image_pil,
                            key_points,
                            keypoint_scores=keypoint_scores,
                            min_score_thresh=min_score_thresh,
                            color=color,
                            radius=radius,
                            use_normalized_coordinates=use_normalized_coordinates,
                            keypoint_edges=keypoint_edges,
                            keypoint_edge_color=keypoint_edge_color,
                            keypoint_edge_width=keypoint_edge_width)
    np.copyto(image, np.array(image_pil))


def draw_keypoints_on_image(image,
                            key_points,
                            keypoint_scores=None,
                            min_score_thresh=0.5,
                            color='red',
                            radius=2,
                            use_normalized_coordinates=True,
                            keypoint_edges=None,
                            keypoint_edge_color='green',
                            keypoint_edge_width=2):
    """Draws keypoints on an image.
  Args:
    image: a PIL.Image object.
    key_points: a numpy array with shape [num_keypoints, 2].
    keypoint_scores: a numpy array with shape [num_keypoints].
    min_score_thresh: a score threshold for visualizing keypoints. Only used if
      keypoint_scores is provided.
    color: color to draw the keypoints with. Default is red.
    radius: keypoint radius. Default value is 2.
    use_normalized_coordinates: if True (default), treat keypoint values as
      relative to the image.  Otherwise treat them as absolute.
    keypoint_edges: A list of tuples with keypoint indices that specify which
      keypoints should be connected by an edge, e.g. [(0, 1), (2, 4)] draws
      edges from keypoint 0 to 1 and from keypoint 2 to 4.
    keypoint_edge_color: color to draw the keypoint edges with. Default is red.
    keypoint_edge_width: width of the edges drawn between keypoints. Default
      value is 2.
  """
    draw = ImageDraw.Draw(image)
    im_width, im_height = image.size
    key_points = np.array(key_points)
    key_points_x = [k[1] for k in key_points]
    key_points_y = [k[0] for k in key_points]
    if use_normalized_coordinates:
        key_points_x = tuple([im_width * x for x in key_points_x])
        key_points_y = tuple([im_height * y for y in key_points_y])
    if keypoint_scores is not None:
        keypoint_scores = np.array(keypoint_scores)
        valid_kpt = np.greater(keypoint_scores, min_score_thresh)
    else:
        valid_kpt = np.where(np.any(np.isnan(key_points), axis=1),
                             np.zeros_like(key_points[:, 0]),
                             np.ones_like(key_points[:, 0]))
    valid_kpt = [v for v in valid_kpt]

    for keypoint_x, keypoint_y, valid in zip(key_points_x, key_points_y, valid_kpt):
        if valid:
            draw.ellipse([(keypoint_x - radius, keypoint_y - radius),
                          (keypoint_x + radius, keypoint_y + radius)],
                         outline=color, fill=color)
    if keypoint_edges is not None:
        for keypoint_start, keypoint_end in keypoint_edges:
            if (keypoint_start < 0 or keypoint_start >= len(key_points) or
                    keypoint_end < 0 or keypoint_end >= len(key_points)):
                continue
            if not (valid_kpt[keypoint_start] and valid_kpt[keypoint_end]):
                continue
            edge_coordinates = [
                key_points_x[keypoint_start], key_points_y[keypoint_start],
                key_points_x[keypoint_end], key_points_y[keypoint_end]
            ]
            draw.line(
                edge_coordinates, fill=keypoint_edge_color, width=keypoint_edge_width)


def draw_mask_on_image_array(image, mask, color='red', alpha=0.4):
    """Draws mask on an image.
  Args:
    image: uint8 numpy array with shape (img_height, img_height, 3)
    mask: a uint8 numpy array of shape (img_height, img_height) with
      values between either 0 or 1.
    color: color to draw the keypoints with. Default is red.
    alpha: transparency value between 0 and 1. (default: 0.4)
  Raises:
    ValueError: On incorrect data type for image or masks.
  """
    if image.dtype != np.uint8:
        raise ValueError('`image` not of type np.uint8')
    if mask.dtype != np.uint8:
        raise ValueError('`mask` not of type np.uint8')
    if np.any(np.logical_and(mask != 1, mask != 0)):
        raise ValueError('`mask` elements should be in [0, 1]')
    if image.shape[:2] != mask.shape:
        raise ValueError('The image has spatial dimensions %s but the mask has '
                         'dimensions %s' % (image.shape[:2], mask.shape))
    rgb = ImageColor.getrgb(color)
    pil_image = Image.fromarray(image)

    solid_color = np.expand_dims(
        np.ones_like(mask), axis=2) * np.reshape(list(rgb), [1, 1, 3])
    pil_solid_color = Image.fromarray(np.uint8(solid_color)).convert('RGBA')
    pil_mask = Image.fromarray(np.uint8(255.0 * alpha * mask)).convert('L')
    pil_image = Image.composite(pil_solid_color, pil_image, pil_mask)
    np.copyto(image, np.array(pil_image.convert('RGB')))


def visualize_boxes_and_labels_on_image_array(
        image,
        boxes,
        classes,
        scores,
        category_index,
        instance_masks=None,
        instance_boundaries=None,
        keypoints=None,
        keypoint_scores=None,
        keypoint_edges=None,
        track_ids=None,
        use_normalized_coordinates=False,
        max_boxes_to_draw=20,
        min_score_thresh=.5,
        agnostic_mode=False,
        line_thickness=4,
        groundtruth_box_visualization_color='black',
        skip_boxes=False,
        skip_scores=False,
        skip_labels=False,
        skip_track_ids=False):
    """Overlay labeled boxes on an image with formatted scores and label names.
  This function groups boxes that correspond to the same location
  and creates a display string for each detection and overlays these
  on the image. Note that this function modifies the image in place, and returns
  that same image.
  Args:
    image: uint8 numpy array with shape (img_height, img_width, 3)
    boxes: a numpy array of shape [N, 4]
    classes: a numpy array of shape [N]. Note that class indices are 1-based,
      and match the keys in the label map.
    scores: a numpy array of shape [N] or None.  If scores=None, then
      this function assumes that the boxes to be plotted are groundtruth
      boxes and plot all boxes as black with no classes or scores.
    category_index: a dict containing category dictionaries (each holding
      category index `id` and category name `name`) keyed by category indices.
    instance_masks: a numpy array of shape [N, image_height, image_width] with
      values ranging between 0 and 1, can be None.
    instance_boundaries: a numpy array of shape [N, image_height, image_width]
      with values ranging between 0 and 1, can be None.
    keypoints: a numpy array of shape [N, num_keypoints, 2], can
      be None.
    keypoint_scores: a numpy array of shape [N, num_keypoints], can be None.
    keypoint_edges: A list of tuples with keypoint indices that specify which
      keypoints should be connected by an edge, e.g. [(0, 1), (2, 4)] draws
      edges from keypoint 0 to 1 and from keypoint 2 to 4.
    track_ids: a numpy array of shape [N] with unique track ids. If provided,
      color-coding of boxes will be determined by these ids, and not the class
      indices.
    use_normalized_coordinates: whether boxes is to be interpreted as
      normalized coordinates or not.
    max_boxes_to_draw: maximum number of boxes to visualize.  If None, draw
      all boxes.
    min_score_thresh: minimum score threshold for a box or keypoint to be
      visualized.
    agnostic_mode: boolean (default: False) controlling whether to evaluate in
      class-agnostic mode or not.  This mode will display scores but ignore
      classes.
    line_thickness: integer (default: 4) controlling line width of the boxes.
    groundtruth_box_visualization_color: box color for visualizing groundtruth
      boxes
    skip_boxes: whether to skip the drawing of bounding boxes.
    skip_scores: whether to skip score when drawing a single detection
    skip_labels: whether to skip label when drawing a single detection
    skip_track_ids: whether to skip track id when drawing a single detection
  Returns:
    uint8 numpy array with shape (img_height, img_width, 3) with overlaid boxes.
  """
    # Create a display string (and color) for every box location, group any boxes
    # that correspond to the same location.
    box_to_display_str_map = collections.defaultdict(list)
    box_to_color_map = collections.defaultdict(str)
    box_to_instance_masks_map = {}
    box_to_instance_boundaries_map = {}
    box_to_keypoints_map = collections.defaultdict(list)
    box_to_keypoint_scores_map = collections.defaultdict(list)
    box_to_track_ids_map = {}
    is_crack = False
    if not max_boxes_to_draw:
        max_boxes_to_draw = boxes.shape[0]
    for i in range(boxes.shape[0]):
        if max_boxes_to_draw == len(box_to_color_map):
            break
        if scores is None or scores[i] > min_score_thresh:
            box = tuple(boxes[i].tolist())
            if instance_masks is not None:
                box_to_instance_masks_map[box] = instance_masks[i]
            if instance_boundaries is not None:
                box_to_instance_boundaries_map[box] = instance_boundaries[i]
            if keypoints is not None:
                box_to_keypoints_map[box].extend(keypoints[i])
            if keypoint_scores is not None:
                box_to_keypoint_scores_map[box].extend(keypoint_scores[i])
            if track_ids is not None:
                box_to_track_ids_map[box] = track_ids[i]
            if scores is None:
                box_to_color_map[box] = groundtruth_box_visualization_color
            else:
                display_str = ''
                if not skip_labels:
                    if not agnostic_mode:
                        if classes[i] in six.viewkeys(category_index):
                            class_name = category_index[classes[i]]['name']
                        else:
                            class_name = 'N/A'
                        display_str = str(class_name)
                if not skip_scores:
                    if not display_str:
                        display_str = '{}%'.format(round(100 * scores[i]))
                    else:
                        display_str = '{}: {}%'.format(display_str, round(100 * scores[i]))
                if not skip_track_ids and track_ids is not None:
                    if not display_str:
                        display_str = 'ID {}'.format(track_ids[i])
                    else:
                        display_str = '{}: ID {}'.format(display_str, track_ids[i])
                box_to_display_str_map[box].append(display_str)
                if agnostic_mode:
                    box_to_color_map[box] = 'DarkOrange'
                elif track_ids is not None:
                    prime_multipler = _get_multiplier_for_color_randomness()
                    box_to_color_map[box] = STANDARD_COLORS[
                        (prime_multipler * track_ids[i]) % len(STANDARD_COLORS)]
                else:
                    box_to_color_map[box] = STANDARD_COLORS[
                        classes[i] % len(STANDARD_COLORS)]
    is_crack = len(box_to_color_map) > 0
    # Draw all boxes onto image.
    for box, color in box_to_color_map.items():
        ymin, xmin, ymax, xmax = box
        if instance_masks is not None:
            draw_mask_on_image_array(
                image,
                box_to_instance_masks_map[box],
                color=color
            )
        if instance_boundaries is not None:
            draw_mask_on_image_array(
                image,
                box_to_instance_boundaries_map[box],
                color='red',
                alpha=1.0
            )
        draw_bounding_box_on_image_array(
            image,
            ymin,
            xmin,
            ymax,
            xmax,
            color=color,
            thickness=0 if skip_boxes else line_thickness,
            display_str_list=box_to_display_str_map[box],
            use_normalized_coordinates=use_normalized_coordinates)
        if keypoints is not None:
            keypoint_scores_for_box = None
            if box_to_keypoint_scores_map:
                keypoint_scores_for_box = box_to_keypoint_scores_map[box]
            draw_keypoints_on_image_array(
                image,
                box_to_keypoints_map[box],
                keypoint_scores_for_box,
                min_score_thresh=min_score_thresh,
                color=color,
                radius=line_thickness / 2,
                use_normalized_coordinates=use_normalized_coordinates,
                keypoint_edges=keypoint_edges,
                keypoint_edge_color=color,
                keypoint_edge_width=line_thickness // 2)

    return image, is_crack
