import os
import shutil

from PIL import Image, ImageFilter, ImageDraw, ImageFont
import numpy
import imutils
import cv2
import dumper
import random as rng
from pathlib import Path

from .utils import cv2_rect, ensure_dir, set_file_perms, WORKDIR

# https://www.pyimagesearch.com/2014/10/20/finding-shapes-images-using-python-opencv/


def find_shapes(image_path):
    """Find shapes in the image, returning bounding boxes around each.
    Writes debug images next to the input image.
    """
    path = Path(image_path)

    img = Image.open(image_path, 'r')
    if not img.mode in ('RGBA', 'LA'):
        print('no alpha channel: {}'.format(img.mode))
        return None

    alpha_layer = img.convert('RGBA').split()[-1]

    alpha_layer = alpha_layer.filter(ImageFilter.GaussianBlur(5))

    threshold = 5
    alpha_layer = alpha_layer.point(lambda p: p > threshold and 255)
    threshold = numpy.array(alpha_layer)

    # alternate method
    # blurred = cv2.GaussianBlur(gray, (5, 5), 0)
    # thresh = cv2.threshold(blurred, 60, 255, cv2.THRESH_BINARY)[1]

    thresh_path = str(path.with_suffix('.thresh.png'))
    cv2.imwrite(thresh_path, threshold)
    os.chmod(thresh_path, 0o664)
    shutil.chown(thresh_path, group='procat')

    contours = cv2.findContours(threshold, cv2.RETR_EXTERNAL, cv2.CHAIN_APPROX_SIMPLE)
    contours = imutils.grab_contours(contours)

    bboxes = []
    for c in contours:
        # bounding rect
        x, y, w, h = cv2.boundingRect(c)
        # essentially center of mass
        # NOT center of the bbox!
        # M = cv2.moments(c)
        # if M["m00"] == 0: M["m00"] = 0.00001
        # cX = int(M["m10"] / M["m00"])
        # cY = int(M["m01"] / M["m00"])
        bboxes.append(cv2_rect(x, y, w, h))

    # draw contours
    contour_image = numpy.zeros((threshold.shape[0], threshold.shape[1], 3), dtype=numpy.uint8)
    for i in range(len(contours)):
        color = (rng.randint(0,512), rng.randint(0,512), rng.randint(0,512))
        cv2.drawContours(contour_image, contours, i, color)
        rect = bboxes[i]
        cv2.rectangle(contour_image, (rect.left, rect.top), (rect.right, rect.bottom), color, 1)
        # cv2.circle(contour_image, (cX, cY), 2, color, -1)
        # cv2.putText(contour_image, "center", (cX - 20, cY - 15),
        #             cv2.FONT_HERSHEY_SIMPLEX, 0.5, color, 1)

    contour_path = str(path.with_suffix('.contour.png'))
    cv2.imwrite(contour_path, contour_image)
    os.chmod(contour_path, 0o664)
    shutil.chown(contour_path, group='procat')

    return img.width, img.height, bboxes


def write_debug_image(workdir, page_num, prods, scribbles):
    """Draw an image with boxes for products, images, and shapes."""
    ensure_dir(workdir)
    path = os.path.join(workdir, f"debug-page{page_num:03d}.png")

    pagew = int(11*72)
    pageh = int(8.5*72)

    img = Image.new('RGBA', (pagew, pageh), 'white')
    draw = ImageDraw.Draw(img, 'RGBA')
    fnt = ImageFont.truetype('/usr/share/fonts/truetype/lato/Lato-Regular.ttf', 10)

    for prod in filter(lambda p: p['page'] == page_num, prods):
        rect = prod['rect']
        fill_color = "hsv(120, 22%, 100%)" if 'matched' in prod else None
        outline_color = "hsv(120, 50%, 100%)"
        draw.rectangle((rect.p1(pageh), rect.p2(pageh)),
                       fill=fill_color, outline=outline_color, width=2)
        bl = rect.p1(pageh)
        draw.text((bl[0] + 3, bl[1] + 3), prod['material'],
                  font=fnt, fill="hsv(120, 22%, 50%)")

    for scribble in filter(lambda s: s['page'] == page_num, scribbles):
        rect = scribble['rect']
        draw.rectangle((rect.p1(pageh), rect.p2(pageh)), outline="hsv(210, 22%, 100%)", width=2)
        for box in scribble['bboxes']:
            draw.rectangle((box.p1(pageh), box.p2(pageh)), outline="hsv(0, 22%, 100%)", width=2)

    img.save(path)
    set_file_perms(path)