"""Support for performing TensorFlow classification on images."""
import logging
import os
import sys
import io
import voluptuous as vol
from PIL import Image, ImageDraw
import numpy as np

try:
    import cv2
except ImportError:
    cv2 = None

try:
    # Verify that the TensorFlow Object Detection API is pre-installed
    import tensorflow as tf  # noqa
    from object_detection.utils import label_map_util  # noqa
except ImportError:
    label_map_util = None

from homeassistant.components.image_processing import (
    CONF_CONFIDENCE,
    CONF_ENTITY_ID,
    CONF_NAME,
    CONF_SOURCE,
    PLATFORM_SCHEMA,
    ImageProcessingEntity,
    draw_box,
)
from homeassistant.core import split_entity_id
from homeassistant.helpers import template
import homeassistant.helpers.config_validation as cv

_LOGGER = logging.getLogger(__name__)

ATTR_MATCHES = "matches"
ATTR_SUMMARY = "summary"
ATTR_TOTAL_MATCHES = "total_matches"

CONF_AREA = "area"
CONF_BOTTOM = "bottom"
CONF_CATEGORIES = "categories"
CONF_CATEGORY = "category"
CONF_FILE_OUT = "file_out"
CONF_GRAPH = "graph"
CONF_LABELS = "labels"
CONF_LEFT = "left"
CONF_MODEL = "model"
CONF_MODEL_DIR = "model_dir"
CONF_RIGHT = "right"
CONF_TOP = "top"

AREA_SCHEMA = vol.Schema(
    {
        vol.Optional(CONF_BOTTOM, default=1): cv.small_float,
        vol.Optional(CONF_LEFT, default=0): cv.small_float,
        vol.Optional(CONF_RIGHT, default=1): cv.small_float,
        vol.Optional(CONF_TOP, default=0): cv.small_float,
    }
)

CATEGORY_SCHEMA = vol.Schema(
    {vol.Required(CONF_CATEGORY): cv.string, vol.Optional(CONF_AREA): AREA_SCHEMA}
)

PLATFORM_SCHEMA = PLATFORM_SCHEMA.extend(
    {
        vol.Optional(CONF_FILE_OUT, default=[]): vol.All(cv.ensure_list, [cv.template]),
        vol.Required(CONF_MODEL): vol.Schema(
            {
                vol.Required(CONF_GRAPH): cv.isfile,
                vol.Optional(CONF_AREA): AREA_SCHEMA,
                vol.Optional(CONF_CATEGORIES, default=[]): vol.All(
                    cv.ensure_list, [vol.Any(cv.string, CATEGORY_SCHEMA)]
                ),
                vol.Optional(CONF_LABELS): cv.isfile,
                vol.Optional(CONF_MODEL_DIR): cv.isdir,
            }
        ),
    }
)


def setup_platform(hass, config, add_entities, discovery_info=None):
    """Set up the TensorFlow image processing platform."""
    model_config = config.get(CONF_MODEL)
    model_dir = model_config.get(CONF_MODEL_DIR) or hass.config.path("tensorflow")
    labels = model_config.get(CONF_LABELS) or hass.config.path(
        "tensorflow", "object_detection", "data", "mscoco_label_map.pbtxt"
    )

    # Make sure locations exist
    if not os.path.isdir(model_dir) or not os.path.exists(labels):
        _LOGGER.error("Unable to locate tensorflow models or label map")
        return

    # append custom model path to sys.path
    sys.path.append(model_dir)

    os.environ["TF_CPP_MIN_LOG_LEVEL"] = "2"
    if label_map_util is None:
        _LOGGER.error(
            "No TensorFlow Object Detection library found! Install or compile "
            "for your system following instructions here: "
            "https://github.com/tensorflow/models/blob/master/research/object_detection/g3doc/installation.md"
        )  # noqa
        return

    if cv2 is None:
        _LOGGER.warning(
            "No OpenCV library found. TensorFlow will process image with "
            "PIL at reduced resolution"
        )

    # Set up Tensorflow graph, session, and label map to pass to processor
    # pylint: disable=no-member
    detection_graph = tf.Graph()
    with detection_graph.as_default():
        od_graph_def = tf.GraphDef()
        with tf.gfile.GFile(model_config.get(CONF_GRAPH), "rb") as fid:
            serialized_graph = fid.read()
            od_graph_def.ParseFromString(serialized_graph)
            tf.import_graph_def(od_graph_def, name="")

    session = tf.Session(graph=detection_graph)
    label_map = label_map_util.load_labelmap(labels)
    categories = label_map_util.convert_label_map_to_categories(
        label_map, max_num_classes=90, use_display_name=True
    )
    category_index = label_map_util.create_category_index(categories)

    entities = []

    for camera in config[CONF_SOURCE]:
        entities.append(
            TensorFlowImageProcessor(
                hass,
                camera[CONF_ENTITY_ID],
                camera.get(CONF_NAME),
                session,
                detection_graph,
                category_index,
                config,
            )
        )

    add_entities(entities)


class TensorFlowImageProcessor(ImageProcessingEntity):
    """Representation of an TensorFlow image processor."""

    def __init__(
        self,
        hass,
        camera_entity,
        name,
        session,
        detection_graph,
        category_index,
        config,
    ):
        """Initialize the TensorFlow entity."""
        model_config = config.get(CONF_MODEL)
        self.hass = hass
        self._camera_entity = camera_entity
        if name:
            self._name = name
        else:
            self._name = "TensorFlow {0}".format(split_entity_id(camera_entity)[1])
        self._session = session
        self._graph = detection_graph
        self._category_index = category_index
        self._min_confidence = config.get(CONF_CONFIDENCE)
        self._file_out = config.get(CONF_FILE_OUT)

        # handle categories and specific detection areas
        categories = model_config.get(CONF_CATEGORIES)
        self._include_categories = []
        self._category_areas = {}
        for category in categories:
            if isinstance(category, dict):
                category_name = category.get(CONF_CATEGORY)
                category_area = category.get(CONF_AREA)
                self._include_categories.append(category_name)
                self._category_areas[category_name] = [0, 0, 1, 1]
                if category_area:
                    self._category_areas[category_name] = [
                        category_area.get(CONF_TOP),
                        category_area.get(CONF_LEFT),
                        category_area.get(CONF_BOTTOM),
                        category_area.get(CONF_RIGHT),
                    ]
            else:
                self._include_categories.append(category)
                self._category_areas[category] = [0, 0, 1, 1]

        # Handle global detection area
        self._area = [0, 0, 1, 1]
        area_config = model_config.get(CONF_AREA)
        if area_config:
            self._area = [
                area_config.get(CONF_TOP),
                area_config.get(CONF_LEFT),
                area_config.get(CONF_BOTTOM),
                area_config.get(CONF_RIGHT),
            ]

        template.attach(hass, self._file_out)

        self._matches = {}
        self._total_matches = 0
        self._last_image = None

    @property
    def camera_entity(self):
        """Return camera entity id from process pictures."""
        return self._camera_entity

    @property
    def name(self):
        """Return the name of the image processor."""
        return self._name

    @property
    def state(self):
        """Return the state of the entity."""
        return self._total_matches

    @property
    def device_state_attributes(self):
        """Return device specific state attributes."""
        return {
            ATTR_MATCHES: self._matches,
            ATTR_SUMMARY: {
                category: len(values) for category, values in self._matches.items()
            },
            ATTR_TOTAL_MATCHES: self._total_matches,
        }

    def _save_image(self, image, matches, paths):
        img = Image.open(io.BytesIO(bytearray(image))).convert("RGB")
        img_width, img_height = img.size
        draw = ImageDraw.Draw(img)

        # Draw custom global region/area
        if self._area != [0, 0, 1, 1]:
            draw_box(
                draw, self._area, img_width, img_height, "Detection Area", (0, 255, 255)
            )

        for category, values in matches.items():
            # Draw custom category regions/areas
            if category in self._category_areas and self._category_areas[category] != [
                0,
                0,
                1,
                1,
            ]:
                label = "{} Detection Area".format(category.capitalize())
                draw_box(
                    draw,
                    self._category_areas[category],
                    img_width,
                    img_height,
                    label,
                    (0, 255, 0),
                )

            # Draw detected objects
            for instance in values:
                label = "{0} {1:.1f}%".format(category, instance["score"])
                draw_box(
                    draw, instance["box"], img_width, img_height, label, (255, 255, 0)
                )

        for path in paths:
            _LOGGER.info("Saving results image to %s", path)
            img.save(path)

    def process_image(self, image):
        """Process the image."""

        if cv2 is None:
            img = Image.open(io.BytesIO(bytearray(image))).convert("RGB")
            img.thumbnail((460, 460), Image.ANTIALIAS)
            img_width, img_height = img.size
            inp = (
                np.array(img.getdata())
                .reshape((img_height, img_width, 3))
                .astype(np.uint8)
            )
            inp_expanded = np.expand_dims(inp, axis=0)
        else:
            img = cv2.imdecode(np.asarray(bytearray(image)), cv2.IMREAD_UNCHANGED)
            inp = img[:, :, [2, 1, 0]]  # BGR->RGB
            inp_expanded = inp.reshape(1, inp.shape[0], inp.shape[1], 3)

        image_tensor = self._graph.get_tensor_by_name("image_tensor:0")
        boxes = self._graph.get_tensor_by_name("detection_boxes:0")
        scores = self._graph.get_tensor_by_name("detection_scores:0")
        classes = self._graph.get_tensor_by_name("detection_classes:0")
        boxes, scores, classes = self._session.run(
            [boxes, scores, classes], feed_dict={image_tensor: inp_expanded}
        )
        boxes, scores, classes = map(np.squeeze, [boxes, scores, classes])
        classes = classes.astype(int)

        matches = {}
        total_matches = 0
        for box, score, obj_class in zip(boxes, scores, classes):
            score = score * 100
            boxes = box.tolist()

            # Exclude matches below min confidence value
            if score < self._min_confidence:
                continue

            # Exclude matches outside global area definition
            if (
                boxes[0] < self._area[0]
                or boxes[1] < self._area[1]
                or boxes[2] > self._area[2]
                or boxes[3] > self._area[3]
            ):
                continue

            category = self._category_index[obj_class]["name"]

            # Exclude unlisted categories
            if self._include_categories and category not in self._include_categories:
                continue

            # Exclude matches outside category specific area definition
            if self._category_areas and (
                boxes[0] < self._category_areas[category][0]
                or boxes[1] < self._category_areas[category][1]
                or boxes[2] > self._category_areas[category][2]
                or boxes[3] > self._category_areas[category][3]
            ):
                continue

            # If we got here, we should include it
            if category not in matches.keys():
                matches[category] = []
            matches[category].append({"score": float(score), "box": boxes})
            total_matches += 1

        # Save Images
        if total_matches and self._file_out:
            paths = []
            for path_template in self._file_out:
                if isinstance(path_template, template.Template):
                    paths.append(
                        path_template.render(camera_entity=self._camera_entity)
                    )
                else:
                    paths.append(path_template)
            self._save_image(image, matches, paths)

        self._matches = matches
        self._total_matches = total_matches