#!/usr/bin/python
# coding:utf-8
# renju:五子棋游戏
# author:zhazh

import sys
import pygame
from collections import namedtuple
from collections import deque
import random

Position = namedtuple('Position', ['x', 'y'])

class Renju(object):
	
	background_filename = 'chessboard.png'
	white_chessball_filename = 'white_chessball.png'
	black_chessball_filename = 'black_chessball.png'
	top, left, space, lines = (20, 20, 36, 15)	# 棋盘格子位置相关???
	color  = (0, 0, 0)	# 棋盘格子线颜色
	
	black_turn = True	# 黑子先手
	ball_coord  = []	# 记录黑子和白子逻辑位置
	
	def init(self):
		try:
			self._chessboard = pygame.image.load(self.background_filename)
			self._white_chessball = pygame.image.load(self.white_chessball_filename).convert_alpha()
			self._black_chessball = pygame.image.load(self.black_chessball_filename).convert_alpha()
			self.font = pygame.font.SysFont('arial', 16)
			self.ball_rect = self._white_chessball.get_rect()
			self.points = [[] for i in range(self.lines)]
			for i in range(self.lines):
				for j in range(self.lines):
					self.points[i].append(Position(self.left + i*self.space, self.top + j*self.space))
			self._draw_board()
		except pygame.error as e:
			print(e)
			sys.exit()
	
	def chessboard(self):
		return self._chessboard
	
	# 在(i,j)位置落子	
	def drop_at(self, i, j):
		pos_x = self.points[i][j].x - int(self.ball_rect.width/2)
		pos_y = self.points[i][j].y - int(self.ball_rect.height/2)

		ball_pos = {'type':0 if self.black_turn else 1, 'coord':Position(i,j)}
		if self.black_turn:	# 轮到黑子下
			self._chessboard.blit(self._black_chessball, (pos_x, pos_y))
		else:
			self._chessboard.blit(self._white_chessball, (pos_x, pos_y))	
			
		self.ball_coord.append(ball_pos)	# 记录已落子信息
		self.black_turn = not self.black_turn	# 切换黑白子顺序
	
	# 画棋盘上的格子线，如果棋盘背景图做的足够精确，可省略此步骤
	def _draw_board(self):	
		# 画坐标数字
		for i in range(1, self.lines):
			coord_text = self.font.render(str(i), True, self.color)
			self._chessboard.blit(coord_text, (self.points[i][0].x-round(coord_text.get_width()/2), self.points[i][0].y-coord_text.get_height()))
			self._chessboard.blit(coord_text, (self.points[0][i].x-coord_text.get_width(), self.points[0][i].y-round(coord_text.get_height()/2)))
			
		for x in range(self.lines):
			# 画横线
			pygame.draw.line(self._chessboard, self.color, self.points[0][x], self.points[self.lines-1][x])
			# 画竖线
			pygame.draw.line(self._chessboard, self.color, self.points[x][0], self.points[x][self.lines-1])
	
	# 判断是否已产生胜方
	def check_over(self):
		if len(self.ball_coord)>8:	# 只有黑白子已下4枚以上才判断
			direct = [(1,0),(0,1),(1,1),(1,-1)]	#横、竖、斜、反斜 四个方向检查
			for d in direct:
				if self._check_direct(d):
					return True
		return False
	
	# 判断最后一个棋子某个方向是否连成5子，direct:(1,0),(0,1),(1,1),(1,-1)
	def _check_direct(self, direct):
		dt_x, dt_y = direct	
		last = self.ball_coord[-1]
		line_ball = []	# 存放在一条线上的棋子
		for ball in self.ball_coord:
			if ball['type'] == last['type']:
				x = ball['coord'].x - last['coord'].x 
				y = ball['coord'].y - last['coord'].y
				if dt_x == 0:
					if x == 0:
						line_ball.append(ball['coord'])
						continue
				if dt_y == 0:
					if y == 0:
						line_ball.append(ball['coord'])
						continue
				if x*dt_y == y*dt_x:
					line_ball.append(ball['coord'])

		if len(line_ball) >= 5:	# 只有5子及以上才继续判断
			sorted_line = sorted(line_ball)
			for i,item in enumerate(sorted_line): 
				index = i+4
				if index < len(sorted_line):
					if dt_x == 0:
						y1 = item.y
						y2 = sorted_line[index].y
						if abs(y1-y2) == 4:	# 此点和第5个点比较y值，如相差为4则连成5子
							return True
					else:
						x1 = item.x
						x2 = sorted_line[index].x
						if abs(x1-x2) == 4: # 此点和第5个点比较x值，如相差为4则连成5子
							return True
				else:
					break
		return False
		
	# 检查(i,j)位置是否已占用	
	def check_at(self, i, j):
		for item in self.ball_coord:
			if (i,j) == item['coord']:
				return False
		return True
	
	# 通过物理坐标获取逻辑坐标		
	def get_coord(self, pos):
		x, y = pos
		i, j = (0, 0)
		oppo_x = x - self.left
		if oppo_x > 0:
			i = round(oppo_x / self.space)	# 四舍五入取整
		oppo_y = y - self.top
		if oppo_y > 0:
			j = round(oppo_y / self.space)
		return (i, j)
			

def main():
	pygame.init()
	size = width,height = 544,544
	screen = pygame.display.set_mode(size, 0, 32)
	pygame.display.set_caption('五子棋')
	font = pygame.font.Font('simhei.ttf', 48)
	clock = pygame.time.Clock()	#设置时钟
	
	
	game_over = False
	renju = Renju()	
	renju.init()

	while True:
		clock.tick(20)	# 设置帧率
		for event in pygame.event.get():
			if event.type == pygame.QUIT:
				sys.exit()
			if event.type == pygame.MOUSEBUTTONDOWN and (not game_over):
				if event.button == 1:	# 按下的是鼠标左键
					i,j = renju.get_coord(event.pos)
					if renju.check_at(i, j):
						renju.drop_at(i, j)
						if renju.check_over():	# 已产生胜方
							text = ''
							if renju.black_turn:
								text = '白方获胜，游戏结束！'
							else:
								text = '黑方获胜，游戏结束！'
							gameover_text = font.render(text, True, (255,0,0))
							renju.chessboard().blit(gameover_text, (round(width/2-gameover_text.get_width()/2), round(height/2-gameover_text.get_height()/2)))
							game_over = True
					else:
						print('此位置已占用，不能在此落子')
		
		screen.blit(renju.chessboard(),(0,0))
		pygame.display.update()
	pygame.quit()

main()