import PySimpleGUI as sg, random
import numpy as np
from typing import List, Any, Union, Tuple, Dict


"""
    Sudoku Puzzle Demo
    
    How to easily generate a GUI for a Sudoku puzzle.
    The Window definition and creation is a single line of code.
    
    Code to generate a playable puzzle was supplied from:
    https://github.com/MorvanZhou/sudoku
    
    Copyright 2020 PySimpleGUI.com
    
"""


def generate_sudoku(mask_rate):
    """
    Create a Sukoku board

    :param mask_rate: % of squares to hide
    :type mask_rate: float
    :rtype: List[numpy.ndarry, numpy.ndarry]
    """
    while True:
        n = 9
        solution = np.zeros((n, n), np.int)
        rg = np.arange(1, n + 1)
        solution[0, :] = np.random.choice(rg, n, replace=False)
        try:
            for r in range(1, n):
                for c in range(n):
                    col_rest = np.setdiff1d(rg, solution[:r, c])
                    row_rest = np.setdiff1d(rg, solution[r, :c])
                    avb1 = np.intersect1d(col_rest, row_rest)
                    sub_r, sub_c = r//3, c//3
                    avb2 = np.setdiff1d(np.arange(0, n+1), solution[sub_r*3:(sub_r+1)*3, sub_c*3:(sub_c+1)*3].ravel())
                    avb = np.intersect1d(avb1, avb2)
                    solution[r, c] = np.random.choice(avb, size=1)
            break
        except ValueError:
            pass
    puzzle = solution.copy()
    puzzle[np.random.choice([True, False], size=solution.shape, p=[mask_rate, 1 - mask_rate])] = 0
    return puzzle, solution



def check_progress(window, solution):
    """
    Gives you a visual hint on your progress.
    Red - You've got an incorrect number at the location
    Yellow - You're missing an anwer for that location

    :param window: The GUI's Window
    :type window: sg.Window
    :param solution: A 2D array containing the solution
    :type solution: numpy.ndarray
    :return: True if the puzzle has been solved correctly
    :rtype: bool
    """
    solved = True
    for r, row in enumerate(solution):
        for c, col in enumerate(row):
            value = window[r,c].get()
            if value:
                try:
                    value = int(value)
                except:
                    value = 0
                if value != solution[r][c]:
                    window[r,c].update(background_color='red')
                    solved = False
                else:
                    window[r,c].update(background_color=sg.theme_input_background_color())
            else:
                solved = False
                window[r, c].update(background_color='yellow')
    return solved


def create_and_show_puzzle(window):
    # create and display a puzzle by updating the Input elements
    rate = DEFAULT_MASK_RATE
    if window['-RATE-'].get():
        try:
            rate = float(window['-RATE-'].get())
        except:
            pass
    puzzle, solution = generate_sudoku(mask_rate=rate)
    for r, row in enumerate(puzzle):
        for c, col in enumerate(row):
            window[r, c].update(puzzle[r][c] if puzzle[r][c] else '', background_color=sg.theme_input_background_color())
    return puzzle, solution


def main(mask_rate=0.7):
    """"
    The Main GUI - It does it all.

    The "Board" is a grid that's 9 x 9.  Even though the layout is a grid of 9 Frames, the
    addressing of the individual squares is via a key that's a tuple (0,0) to (8,8)
    """




    # It's 1 line of code to make a Sudoku board.  If you don't like it, then replace it.
    # Dude (Dudette), it's 1-line of code.  If you don't like the board, write a line of code.
    # The keys for the inputs are tuples (0-8, 0-8) that reference each Input Element.
    # Get an input element for a position using:    window[row, col]
    # To get a better understanding, take it apart. Spread it out. You'll learn in the process.
    window = sg.Window('Sudoku',
                       [[sg.Frame('', [[sg.I(random.randint(1,9), justification='r', size=(3,1),enable_events=True, key=(fr*3+r,fc*3+c)) for c in range(3)] for r in range(3)]) for fc in range(3)] for fr in range(3)] +
                       [[sg.B('Solve'), sg.B('Check'), sg.B('Hint'), sg.B('New Game'), sg.T('Mask rate (0-1)'), sg.In(str(mask_rate), size=(3,1),key='-RATE-')],], finalize=True)

    # create and display a puzzle by updating the Input elements

    puzzle, solution = create_and_show_puzzle(window)
    check_showing = False
    while True:         # The Event Loop
        event, values = window.read()
        if event == sg.WIN_CLOSED:
            break

        if event == 'Solve':
            for r, row in enumerate(solution):
                for c, col in enumerate(row):
                    window[r, c].update(solution[r][c], background_color=sg.theme_input_background_color())
        elif event == 'Check':
            check_showing = True
            solved = check_progress(window, solution)
            if solved:
                sg.popup('Solved! You have solved the puzzle correctly.')
        elif event == 'Hint':
            elem = window.find_element_with_focus()
            try:
                elem.update(solution[elem.Key[0]][elem.Key[1]], background_color=sg.theme_input_background_color())
            except:
                pass        # Likely because an input element didn't have focus
        elif event == 'New Game':
            puzzle, solution = create_and_show_puzzle(window)
        elif check_showing:      # an input was changed, so clear any background colors from prior hints
            check_showing = False
            for r, row in enumerate(solution):
                for c, col in enumerate(row):
                    window[r, c].update(background_color=sg.theme_input_background_color())
    window.close()

if __name__ == "__main__":
    DEFAULT_MASK_RATE = 0.7     # % Of cells to hide
    main(DEFAULT_MASK_RATE)