ChessMain.py

"""
This is our driver file, responsible for handling user input and displaying current GameState object.
"""

import pygame as p
from Chess import ChessEngine

WIDTH = HEIGHT = 512 #400 is another good option
DIMENSION = 8 #dimensions of chess board are 8x8
SQ_SIZE = HEIGHT // DIMENSION
MAX_FPS = 15 # for animation later on
IMAGES = {}


# Initialize a global dictionary of images. This will be called exactly once in the main

def loadImages():
    pieces = ['wp', 'wR', 'wN', 'wB', 'wK', 'wQ', 'bp', 'bR', 'bN', 'bB', 'bK', 'bQ']
    for piece in pieces:
        IMAGES[piece] = p.transform.scale(p.image.load("Chess/images/" + piece + ".png"), (SQ_SIZE, SQ_SIZE))
    # Note: we can access an image by saying 'IMAGES['wp']'


'''
The main driver for our code. This will handle user input and updating the graphics.
'''

def main():
    p.init()
    screen = p.display.set_mode((WIDTH, HEIGHT))
    clock = p.time.Clock()
    screen.fill(p.Color("white"))
    gs = ChessEngine.GameState()
    validMoves = gs.getValidMoves()
    moveMade = False # flag variable for when a move is made
    animate = False # flag variable for when we should animate a move
    loadImages() # only do this once, before the while loop
    running = True
    sqSelected = () # no square is selected initially
    # keeps track of the last click of the user in form od a tuple: (row, col)
    playerClicks = [] # keeps track of player clicks(two tuples: [(6, 4), (4, 4)]
    gameOver = False
    while running:
        for e in p.event.get():
            if e.type == p.QUIT:
                running = False
            #mouse handler
            elif e.type == p.MOUSEBUTTONDOWN:
                if not gameOver:
                    location = p.mouse.get_pos() # (x, y) location of mouse
                    col = location[0] // SQ_SIZE
                    row = location[1] // SQ_SIZE
                    if sqSelected == (row, col):    # user clicked the same square twice
                        sqSelected = () # deselect
                        playerClicks = [] # clear player clicks
                    else:
                        sqSelected = (row, col)
                        playerClicks.append(sqSelected) #append for both 1st and 2nd clicks
                    if len(playerClicks) == 2: # after 2nd click
                        move = ChessEngine.Move(playerClicks[0], playerClicks[1], gs.board)
                        print(move.getChessNotation())
                        for i in range(len(validMoves)):
                            if move == validMoves[i]:
                                gs.makeMove(validMoves[i])
                                moveMade = True
                                animate = True
                                sqSelected = () #reset user clicks
                                playerClicks = []
                        if not moveMade:
                            playerClicks = [sqSelected]
            # key handler
            elif e.type == p.KEYDOWN:
                if e.key == p.K_z:  # undo move when 'z' is pressed
                    gs.undoMove()
                    moveMade = True
                    animate = False
                if e.key == p.K_r: #reset the board when 'r' is pressed
                    gs = ChessEngine.GameState()
                    validMoves = gs.getValidMoves()
                    sqSelected = ()
                    playerClicks = []
                    moveMade = False
                    animate = False

        if moveMade:
            if animate:
                animateMove(gs.moveLog[-1], screen, gs.board, clock)
            validMoves = gs.getValidMoves()
            moveMade = False

        drawGameState(screen, gs, validMoves, sqSelected)

        if gs.checkMate:
            gameOver = True
            if gs.whiteToMove:
                drawText(screen, 'Black wins by CheckMate')
            else:
                drawText(screen, 'White wins by CheckMate')
        elif gs.staleMate:
            gameOver = True
            drawText(screen, 'StaleMate')

        clock.tick(MAX_FPS)
        p.display.flip()

'''
Highlight the square selected and moves for the piece selected
'''
def highlightSquare(screen, gs, validMoves, sqSelected):
    if sqSelected != ():
        r, c = sqSelected
        if gs.board[r][c][0] == ('w' if gs.whiteToMove else 'b'): # sqSelected is a piece that can be moved
            # highlight selected square
            s = p.Surface((SQ_SIZE, SQ_SIZE))
            s.set_alpha(100) # transparency value -> 0 transparent, 255 opaque
            s.fill(p.Color('blue'))
            screen.blit(s, (c * SQ_SIZE, r * SQ_SIZE))
            # highlight moves from this square
            s.fill(p.Color('yellow'))
            for move in validMoves:
                if move.startRow == r and move.startCol == c:
                    screen.blit(s, (move.endCol * SQ_SIZE, move.endRow * SQ_SIZE))

'''
Responsible for all the graphics within a current game state.
'''
def drawGameState(screen, gs, validMoves, sqSelected):
    drawBoard(screen) # draw aquares on the board
    highlightSquare(screen, gs, validMoves, sqSelected)
    drawPieces(screen, gs.board)    # draw pieces on top of those squares



'''
Draw the squares on the board. Top left square is always light.
'''
def drawBoard(screen):
    global colors
    colors = [p.Color("light gray"), p.Color("dark gray")]
    for r in range(DIMENSION):
        for c in range(DIMENSION):
            color = colors[(r + c) % 2]
            p.draw.rect(screen, color, p.Rect(c * SQ_SIZE, r * SQ_SIZE, SQ_SIZE, SQ_SIZE))


'''
Draw the pieces on the board using the current GameState.board
'''
def drawPieces(screen, board):
    for r in range(DIMENSION):
        for c in range(DIMENSION):
            piece = board[r][c]
            if piece != "--":
                screen.blit(IMAGES[piece], p.Rect(c * SQ_SIZE, r * SQ_SIZE, SQ_SIZE, SQ_SIZE))

'''
Animating a move
'''
def animateMove(move, screen, board, clock):
    global colors
    coords = [] # list of coordinates that the animation will move through
    dR = move.endRow - move.startRow
    dC = move.endCol - move.startCol
    framesPerSquare = 10 # frames to move one square
    frameCount = (abs(dR) + abs(dC)) * framesPerSquare
    for frame in range(frameCount + 1):
        r, c = (move.startRow + dR * frame / frameCount, move.startCol + dC * frame / frameCount)
        drawBoard(screen)
        drawPieces(screen, board)
        # erase the piece moves from it's ending square
        color = colors[(move.endRow + move.endCol) % 2]
        endSquare = p.Rect(move.endCol * SQ_SIZE, move.endRow * SQ_SIZE, SQ_SIZE, SQ_SIZE)
        p.draw.rect(screen, color, endSquare)
        #draw captured piece onto rectsngle
        if move.pieceCaptured != "--":
            screen.blit(IMAGES[move.pieceCaptured], endSquare)
        #draw moving piece
        screen.blit(IMAGES[move.pieceMoved], p.Rect(c * SQ_SIZE, r * SQ_SIZE, SQ_SIZE, SQ_SIZE))
        p.display.flip()
        clock.tick(60)


def drawText(screen, text):
    font = p.font.SysFont("Helvicta", 32, True, False)
    textObject = font.render(text, 0, p.Color("White"))
    textLocation = p.Rect(0, 0, WIDTH, HEIGHT).move(WIDTH / 2 - textObject.get_width() / 2, HEIGHT / 2 - textObject.get_height() / 2)
    screen.blit(textObject, textLocation)
    textObject = font.render(text, 0, p.Color("Black"))
    screen.blit(textObject, textLocation.move(2, 2))

# change to commit
if __name__ == "__main__":
    main()