import pygame

pygame.init()

height = 950
width = 1000
screen = pygame.display.set_mode([width, height])
pygame.display.set_caption('Checkers match')
font = pygame.font.SysFont('Arial', 20)
big_font = pygame.font.SysFont('calibri', 45)
timer = pygame.time.Clock()
fps = 60

# game variables and images

white_pieces = ['man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man']
white_locations = [(0, 7), (2, 7), (4, 7), (6, 7), (1, 6), (3, 6), (5, 6), (7, 6), (0, 5), (2, 5), (4, 5), (6, 5)]
black_pieces = ['man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man']
black_locations = [(1, 0), (3, 0), (5, 0), (7, 0), (0, 1), (2, 1), (4, 1), (6, 1), (1, 2), (3, 2), (5, 2), (7, 2)]

captured_pieces_white = []
captured_pieces_black = []

turn_step = 0
selection = 100
valid_moves = []

# piece images
white_man = pygame.image.load('Checkers Piece White(man).png')
white_man = pygame.transform.scale(white_man, (150, 150))
white_man_small = pygame.transform.scale(white_man, (45, 45))

white_king = pygame.image.load('Checkers Piece White(king).png')
white_king = pygame.transform.scale(white_king, (150, 150))
white_king_small = pygame.transform.scale(white_king, (45, 45))
white_images = [white_man, white_king]
small_white_images = [white_man_small, white_king_small]

black_man = pygame.image.load('Checkers Piece Black(man).png')
black_man = pygame.transform.scale(black_man, (150, 150))
black_man_small = pygame.transform.scale(black_man, (45, 45))
black_king = pygame.image.load('Checkers Piece Black(king).png')
black_king = pygame.transform.scale(black_king, (150, 150))
black_king_small = pygame.transform.scale(black_king, (45, 45))
black_images = [black_man, black_king]
small_black_images = [black_man_small, black_king_small]

piece_list = ['man', 'king']

# check variables
winner = ''
game_over = False


# draw main game board
def draw_board():
    for i in range(32):
        column = i % 4
        row = i // 4
        if row % 2 == 0:
            pygame.draw.rect(screen, 'light gray', [600 - (column * 200), row * 100, 100, 100])
        else:
            pygame.draw.rect(screen, 'light gray', [700 - (column * 200), row * 100, 100, 100])
        pygame.draw.rect(screen, 'gray', [0, 800, width, 200])
        pygame.draw.rect(screen, 'red', [0, 800, width, 150], 5)
        pygame.draw.rect(screen, 'red', [800, 0, 200, height], 5)
        status_text = ['WHITE: Select a piece to move', 'WHITE: Select a place to move to',
                       'BLACK: Select a piece to move', 'BLACK: Select a place to move to']
        screen.blit(big_font.render(status_text[turn_step], True, 'black'), (20, 820))
        for j in range(9):
            pygame.draw.line(screen, 'black', (0, 100 * j), (800, 100 * j), 2)
            pygame.draw.line(screen, 'black', (100 * j, 0), (100 * j, 800), 2)
        screen.blit(big_font.render('FORFEIT', True, 'black'), (825, 850))


# draw pieces
def draw_pieces():
    square_size = 100
    piece_size = 150
    offset = (square_size - piece_size) // 2
    for i in range(len(black_pieces)):
        index = piece_list.index(white_pieces[i])
        x_pos = white_locations[i][0] * square_size + offset
        y_pos = white_locations[i][1] * square_size + offset
        if white_pieces[i] == 'man':
            screen.blit(white_man, (x_pos, y_pos))
        else:
            screen.blit(white_images[index], (x_pos, y_pos))
        if turn_step < 2:
            if selection == i:
                pygame.draw.rect(screen, 'gold',
                                 [white_locations[i][0] * 100 + 1, white_locations[i][1] * 100 + 1, 100, 100], 2)

        if len(black_pieces) != len(black_locations):
            print(
                f"Error: Mismatch in lengths. black_pieces: {len(black_pieces)}, black_locations: {len(black_locations)}")
            return
    for i in range(len(black_pieces)):
        if i >= len(black_locations):  # Safety check
            print(f"Error: Index {i} is out of range for black_locations")
            break
        index = piece_list.index(black_pieces[i])
        x_pos = black_locations[i][0] * square_size + offset
        y_pos = black_locations[i][1] * square_size + offset
        if black_pieces[i] == 'man':
            screen.blit(black_man, (x_pos, y_pos))
        else:
            screen.blit(black_images[index], (x_pos, y_pos))
        if turn_step >= 2:
            if selection == i:
                pygame.draw.rect(screen, 'silver',
                                 [black_locations[i][0] * 100 + 1, black_locations[i][1] * 100 + 1, 100, 100], 2)


# check all valid piece options on board
def check_options(pieces, locations, turn):
    if len(pieces) != len(locations):
        print(f"Error: Mismatch in lengths. Pieces: {len(pieces)}, Locations: {len(locations)}")
        return []

    moves_list = []
    all_moves_list = []
    for i in range(len(pieces)):
        location = locations[i]
        piece = pieces[i]
        if piece == 'man':
            moves_list = check_man(location, turn)
        elif piece == 'king':
            moves_list = check_king(location, turn)
        all_moves_list.append(moves_list)
    return all_moves_list


# check valid man moves
def check_man(position, colour):
    moves_list = []
    if colour == 'white':
        if (position[0] - 1 >= 0 and position[1] - 1 >= 0 and (
        position[0] - 1, position[1] - 1) not in white_locations and (
        position[0] - 1, position[1] - 1) not in black_locations):
            moves_list.append((position[0] - 1, position[1] - 1))
        if (position[0] + 1 < 8 and position[1] - 1 >= 0 and (
        position[0] + 1, position[1] - 1) not in white_locations and (
        position[0] + 1, position[1] - 1) not in black_locations):
            moves_list.append((position[0] + 1, position[1] - 1))

        # Capture pieces
        if (position[0] - 2 >= 0 and position[1] - 2 >= 0 and (
        position[0] - 1, position[1] - 1) in black_locations and (
        position[0] - 2, position[1] - 2) not in white_locations and (
        position[0] - 2, position[1] - 2) not in black_locations):
            moves_list.append((position[0] - 2, position[1] - 2))
            black_locations.remove((position[0] - 1, position[1] - 1))
        if (position[0] + 2 < 8 and position[1] - 2 >= 0 and (position[0] + 1, position[1] - 1) in black_locations and (
        position[0] + 2, position[1] - 2) not in white_locations and (
        position[0] + 2, position[1] - 2) not in black_locations):
            moves_list.append((position[0] + 2, position[1] - 2))
            black_locations.remove((position[0] + 1, position[1] - 1))

    else:
        if (position[0] - 1 >= 0 and position[1] + 1 < 8 and (
        position[0] - 1, position[1] + 1) not in white_locations and (
        position[0] - 1, position[1] + 1) not in black_locations):
            moves_list.append((position[0] - 1, position[1] + 1))
        if (position[0] + 1 < 8 and position[1] + 1 < 8 and (
        position[0] + 1, position[1] + 1) not in white_locations and (
        position[0] + 1, position[1] + 1) not in black_locations):
            moves_list.append((position[0] + 1, position[1] + 1))

        # capture pieces
        if (position[0] - 2 >= 0 and position[1] + 2 < 8 and (position[0] - 1, position[1] + 1) in white_locations and (
        position[0] - 2, position[1] + 2) not in white_locations and (
        position[0] - 2, position[1] + 2) not in black_locations):
            moves_list.append((position[0] - 2, position[1] + 2))
            white_locations.remove((position[0] - 1, position[1] + 1))
        if (position[0] + 2 < 8 and position[1] + 2 < 8 and (position[0] + 1, position[1] + 1) in white_locations and (
        position[0] + 2, position[1] + 2) not in white_locations and (
        position[0] + 2, position[1] + 2) not in black_locations):
            moves_list.append((position[0] + 2, position[1] + 2))
            white_locations.remove((position[0] + 1, position[1] + 1))

    return moves_list


# check valid king moves
def check_king(position, colour):
    moves_list = []
    if colour == 'white':
        ally_list = white_locations
    else:
        ally_list = black_locations
    directions = [(-1, -1), (-1, 1), (1, -1), (1, 1)]
    for i in range(4):
        target = (position[0] + directions[i][0], position[1] + directions[i][1])
        if target not in ally_list and 0 <= target[0] <= 7 and 0 <= target[1] <= 7:
            moves_list.append(target)
    return moves_list


# check valid moves only for selected piece
def check_valid_moves():
    if turn_step < 2:
        options_list = white_options
    else:
        options_list = black_options
    valid_options = options_list[selection]
    return valid_options


# draw valid moves on screen
def draw_valid(moves):
    if turn_step < 2:
        colour = 'gold'
    else:
        colour = 'blue'
    for i in range(len(moves)):
        pygame.draw.circle(screen, colour, (moves[i][0] * 100 + 50, moves[i][1] * 100 + 50), 5)


# draw captured pieces on side of screen
def draw_captured():
    for i in range(len(captured_pieces_white)):
        captured_piece = captured_pieces_white[i]
        index = piece_list.index(captured_piece)
        screen.blit(small_black_images[index], (825, 5 + 50 + i))
    for i in range(len(captured_pieces_black)):
        captured_piece = captured_pieces_black[i]
        index = piece_list.index(captured_piece)
        screen.blit(small_white_images[index], (925, 5 + 50 + i))


def draw_game_over():
    pygame.draw.rect(screen, 'black', [200, 200, 400, 70])
    screen.blit(font.render(f'{winner} is victorious', True, 'yellow'), (210, 210))
    screen.blit(font.render(f'Press ENTER to start new game', True, 'green'), (210, 240))


# main game loop

black_options = check_options(black_pieces, black_locations, 'black')
white_options = check_options(white_pieces, white_locations, 'white')

run = True
while run:
    timer.tick(fps)
    screen.fill('dimgray')
    draw_board()
    draw_pieces()
    draw_captured()
    if selection != 100:
        valid_moves = check_valid_moves()
        draw_valid(valid_moves)

    # event handling
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            run = False
        if event.type == pygame.MOUSEBUTTONDOWN and event.button == 1 and not game_over:
            x_coord = event.pos[0] // 100
            y_coord = event.pos[1] // 100
            click_coords = (x_coord, y_coord)
            if turn_step <= 1:
                if click_coords == (8, 8) or click_coords == (9, 8):
                    winner = 'Black'
                    game_over = True
                if click_coords in white_locations:
                    selection = white_locations.index(click_coords)
                    if turn_step == 0:
                        turn_step = 1
                if click_coords in valid_moves and selection != 100:
                    white_locations[selection] = click_coords
                    if click_coords in black_locations:
                        black_piece = black_locations.index(click_coords)
                        captured_pieces_white.append(black_pieces[black_piece])
                        if black_pieces[black_piece] == 0:
                            winner = 'White'
                            game_over = True
                        black_pieces.pop(black_piece)
                        black_locations.pop(black_piece)
                    black_options = check_options(black_pieces, black_locations, 'black')
                    white_options = check_options(white_pieces, white_locations, 'white')
                    turn_step = 2
                    selection = 100
                    valid_moves = []
            if turn_step > 1:
                if len(black_pieces) == 0:
                    winner = 'White'
                    game_over = True
                if click_coords in black_locations:
                    selection = black_locations.index(click_coords)
                    if turn_step == 2:
                        turn_step = 3
                        black_piece = black_locations.index(click_coords)
                        captured_pieces_white.append(black_pieces[black_piece])
                        black_pieces.pop(black_piece)
                        black_locations.pop(black_piece)
                if click_coords in valid_moves and selection != 100:
                    black_locations[selection] = click_coords
                    if click_coords in white_locations:
                        white_piece = white_locations.index(click_coords)
                        captured_pieces_black.append(white_pieces[white_piece])
                        white_pieces.pop(white_piece)
                        white_locations.pop(white_piece)
                        if len(white_pieces) == 0:
                            winner = 'Black'
                            game_over = True
                    black_options = check_options(black_pieces, black_locations, 'black')
                    white_options = check_options(white_pieces, white_locations, 'white')
                    turn_step = 0
                    selection = 100
                    valid_moves = []
        if event.type == pygame.KEYDOWN and game_over:
            if event.key == pygame.K_RETURN:
                game_over = False
                winner = ''
                white_pieces = ['man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man']
                white_locations = [(0, 7), (2, 7), (4, 7), (6, 7), (1, 6), (3, 6), (5, 6), (7, 6), (0, 5), (2, 5),
                                   (4, 5), (6, 5)]
                black_pieces = ['man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man', 'man']
                black_locations = [(1, 0), (3, 0), (5, 0), (7, 0), (0, 1), (2, 1), (4, 1), (6, 1), (1, 2), (3, 2),
                                   (5, 2), (7, 2)]
                turn_step = 0
                selection = 100
                valid_moves = []
                black_options = check_options(black_pieces, black_locations, 'black')
                white_options = check_options(white_pieces, white_locations, 'white')
                captured_pieces_white = []
                captured_pieces_black = []
    if winner != '':
        game_over = True
        draw_game_over()
    pygame.display.flip()
pygame.quit()