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 django.conf import settings

from .utils import cv2_rect

WORKDIR = os.path.join(settings.ASSET_DIR, 'markup', 'work')

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


def find_shapes(image_path):
    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'))
    # print('write to', thresh_path)
    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)
    # print("{} shapes".format(len(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"])
        #print('add contour rect: {}'.format(cv2_rect(x, y, w, h)))
        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)):
        # compute the center of the contour
        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'))
    #print('write to', contour_path)
    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(cat_name, page_num, prods, scribbles):
    path = os.path.join(WORKDIR, "debug-{}-{}.png".format(cat_name, page_num))

    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)