import cv2
import numpy as np
import os
import shutil


def transform(pos):
    # This function is used to find the corners of the object and the dimensions of the object
    pts = []
    n = len(pos)
    for i in range(n):
        pts.append(list(pos[i][0]))

    sums = {}
    diffs = {}
    tl = tr = bl = br = 0
    for i in pts:
        x = i[0]
        y = i[1]
        sum = x + y
        diff = y - x
        sums[sum] = i
        diffs[diff] = i
    sums = sorted(sums.items())
    diffs = sorted(diffs.items())
    n = len(sums)
    rect = [sums[0][1], diffs[0][1], diffs[n - 1][1], sums[n - 1][1]]
    #      top-left   top-right   bottom-left   bottom-right

    h1 = np.sqrt((rect[0][0] - rect[2][0]) ** 2 + (rect[0][1] - rect[2][1]) ** 2)  # height of left side
    h2 = np.sqrt((rect[1][0] - rect[3][0]) ** 2 + (rect[1][1] - rect[3][1]) ** 2)  # height of right side
    h = max(h1, h2)

    w1 = np.sqrt((rect[0][0] - rect[1][0]) ** 2 + (rect[0][1] - rect[1][1]) ** 2)  # width of upper side
    w2 = np.sqrt((rect[2][0] - rect[3][0]) ** 2 + (rect[2][1] - rect[3][1]) ** 2)  # width of lower side
    w = max(w1, w2)

    return int(w), int(h), rect


img1 = cv2.imread('images.jpg')

dim = (4952, 6824)  # Original Image size
dim = (2476, 3412)  # Resized
img = cv2.resize(img1, dim, interpolation=cv2.INTER_AREA)  # Commet this line to stop resize
edge = cv2.Canny(img, 100, 100)
_, contours, _ = cv2.findContours(edge.copy(), 1, 1)
# n=len(contours)
max_area = 0
pos = 0
for i in contours:
    area = cv2.contourArea(i)
    if area > max_area:
        max_area = area
        pos = i

peri = cv2.arcLength(pos, True)
approx = cv2.approxPolyDP(pos, 0.02 * peri, True)

size = img.shape
w, h, arr = transform(approx)
pts2 = np.float32([[0, 0], [w, 0], [0, h], [w, h]])
pts1 = np.float32(arr)
print('pt',pts1,'\npt2',pts2)

M = cv2.getPerspectiveTransform(pts1*2, pts2*2)
dst = cv2.warpPerspective(img1, M, (w*2, h*2))

# cv2.namedWindow('dst',cv2.WINDOW_NORMAL)
cv2.imshow('dst',dst)
# image=cv2.cvtColor(dst,cv2.COLOR_BGR2GRAY)
image = cv2.resize(dst, (w*2, h*2), interpolation=cv2.INTER_AREA)

cv2.namedWindow('OUTPUT',cv2.WINDOW_NORMAL)
cv2.imshow('OUTPUT', image)
# cv2.namedWindow('edge',cv2.WINDOW_NORMAL)
# cv2.imshow('edge',edge)
cv2.imwrite('crop.jpg',image)
cv2.waitKey(0)
cv2.destroyAllWindows()