"""
img_to_path_outline.py
Andrew Lorimer, November 2024
Monash University

Extracts contours (outlines) from a monochrome image, converts to a series of 
points representing straight lines, and outputs these points in the 
appropriate format for laser writing with the confocal setup. For use with 
LabView script.
"""

import cv2
import numpy as np
import sys

SPEED = 100         # um/s
REAL_DIM = 100.0    # um
Z = 0.0             # um

np.set_printoptions(threshold=sys.maxsize)

def row(x, y, z, on, t):
    return "1\t{:.3f}\t{:.3f}\t{:.3f}\t{:.3f}\t{:d}\n".format(x, y, z, on, t)


im = cv2.imread('test_img/test_img_1.png', cv2.IMREAD_GRAYSCALE)
dim = im.shape

if (dim[0] != dim[1]):
    print("Error: image must be square")
    sys.exit()

output = ""

# Go to origin point (laser off)
output += row(0.0, 0.0, Z, 0.0, SPEED)

result_fill = np.ones(dim, np.uint8) * 255
result_borders = np.zeros(dim, np.uint8)

# the '[:-1]' is used to skip the contour at the outer border of the image
contours = cv2.findContours(im, cv2.RETR_LIST,
                            cv2.CHAIN_APPROX_SIMPLE)[0][:-1]

print(len(contours))
print(contours[-1][:10])
print(contours[0].shape)

cv2.drawContours(result_fill, contours, -1, 0, -1)
cv2.drawContours(result_borders, contours, -1, 255, 1)

for contour in contours:
    for i, point in enumerate(contour):
        point_real = point[0] / dim[0] * REAL_DIM
        laser_on = 0.0 if i == 0 else 1.0
        output += row(point_real[0], point_real[1], Z, laser_on, SPEED)

output += row(0.0, 0.0, Z, 0.0, SPEED)

with open('path.txt', 'w') as f:
    f.write(output)


# Questions
# Thickness of lines
# Stage uncertainty/increment
# Sample dimensions
# Dwell time