# Importing the dependencies
import cv2
import numpy as np

# Defining variables to store coordinates where the second image has to be placed
positions = []
positions2 = []
count = 0

# Mouse callback function
def draw_circle(event, x, y, flags, param):
    global positions, count
    # If event is Left Button Click then store the coordinate in the lists, positions and positions2
    if event == cv2.EVENT_LBUTTONUP:
        cv2.circle(room_draw, (x, y), 2, (255, 0, 0), -1)
        positions.append([x, y])
        if count != 3:
            positions2.append([x, y])
        elif count == 3:
            positions2.insert(2, [x, y])
        count += 1


# Reading the two images and storing it in variables room and dp
room = cv2.imread("./data/room2.jpg")
room_draw = room.copy()

dp = cv2.imread("./data/carpet.jpeg")

# Defing a window named 'image' and set the callback to define the destination points
cv2.namedWindow("image")
cv2.setMouseCallback("image", draw_circle)

while True:
    cv2.imshow("image", room_draw)
    k = cv2.waitKey(20) & 0xFF
    if k == 27 or count > 3:
        break

cv2.destroyAllWindows()

height, width = room.shape[:2]
h1, w1 = dp.shape[:2]

pts1 = np.float32([[0, 0], [w1, 0], [0, h1], [w1, h1]])
pts2 = np.float32(positions)

# Calculate homography
h, mask = cv2.findHomography(pts1, pts2, cv2.RANSAC, 5.0)

height, width, channels = room.shape
im1Reg = cv2.warpPerspective(dp, h, (width, height))

# Masking and blending
mask2 = np.zeros(room.shape, dtype=np.uint8)

roi_corners2 = np.int32(positions2)

channel_count2 = room.shape[2]
ignore_mask_color2 = (255,) * channel_count2

cv2.fillConvexPoly(mask2, roi_corners2, ignore_mask_color2)

mask2 = cv2.bitwise_not(mask2)
masked_image2 = cv2.bitwise_and(room, mask2)

# Using Bitwise or to merge the two images
final = cv2.bitwise_or(im1Reg, masked_image2)

# Show results and write to file
cv2.imshow("Final", final)
cv2.imwrite("Final2.jpg", final)

cv2.waitKey(0) & 0xFF
cv2.destroyAllWindows()