#!/usr/bin/env python
# coding: utf-8

# In[ ]:


# requirements...

# !pip install python-sat
# !pip install opencv-python
# !pip install Pillow
# !pip install numpy


# In[1]:


from pysat.examples.hitman import Hitman
import numpy as np
import cv2
from PIL import Image
from IPython.display import display

def get_sat_clauses(n, d):
    clauses = []

    for y in range(n + 1):
        for x in range(n):
            neighbours = []
            for shift in range(d):
                neighbours.append((x - shift, y))
                neighbours.append((x - shift, y - d))
            
            neighbours_rev = [tuple(reversed(n)) for n in neighbours]
            clauses.append(neighbours)
            clauses.append(neighbours_rev)

    all_clauses = sorted({c for clist in clauses for c in clist})

    id_map = {i + 1: c for i, c in enumerate(all_clauses)}
    clause_map = {c: i for i,c in id_map.items()}

    clauses = [
        [clause_map[c] for c in clause] 
        for clause in clauses
    ]
    return clauses, id_map

def get_solution_helper(n, d, return_id_map=False):
    solver = Hitman(solver='m22', htype='lbx')
    clauses, id_map = get_sat_clauses(n, d)
    for c in clauses:
        solver.hit(c)
    out = solver.get()
    if return_id_map:
        return out, id_map
    return out
        
def get_solution(n):
    ds = list(range(1, n + 1))
    sols = [get_solution_helper(n, d) for d in ds]
    sol_sizes = [len(s) for s in sols]
    best_idx = np.argmin(sol_sizes)
    return ds[best_idx], sol_sizes[best_idx]
    
def plot_solution(n, d, solution, id_map):
    img = np.ones((3 * n * 100, 3 * n * 100, 3)) * 255

    for i in solution:
        left, top = id_map[i]
        left = left * 100 + n * 100
        top = top * 100 + n * 100
        left += np.random.randint(-7,7)
        top += np.random.randint(-7,7)
        right, bottom = left + d * 100, top + d * 100
        color = [int(x) for x in np.random.randint(0, 256, size=(3,))]
        img = cv2.rectangle(img, (left, top), (right, bottom), thickness=4, color=color)
        centre = (left + right) // 2,(top + bottom) // 2
        img = cv2.rectangle(img, (left, top), (right, bottom), thickness=4, color=color)
        img = cv2.circle(img, centre, radius=20, thickness=-1, color=(255, 0, 0))

    return Image.fromarray(img.astype(np.uint8))

# for n in range(10, 12):
#     d, _ = get_solution(n)
#     solution, id_map = get_solution_helper(n, d, return_id_map=True)
#     print(n, d, len(solution))

for n in range(10, 12):
    d, _ = get_solution(n)

    solution, id_map = get_solution_helper(n, d, return_id_map=True)

    print(n, d, len(solution))

    img = plot_solution(n, d, solution, id_map)
    
    display(img)