Maze Solution Checker

mazechecker.py

import sys, os
from subprocess import Popen, PIPE

if sys.argv[1]=="-d":
	debug=True
	prog=sys.argv[2]
else:
	debug=False
	prog=sys.argv[1]

def solved():
	process.stdin.write('solved\n')
	process.stdin.flush()
	process.stdin.close()
	process.wait()
	print "Maze "+fname+" solved."

for fname in os.listdir("mazes"):
	with open(os.path.join('mazes', fname)) as f:
		maze=list(f)
	has_exit=False
	for i, l in enumerate(maze):
		if "S" in l:
			y=i
			x=l.index("S")
		if "X" in l: has_exit=True

	moves = set()
	dirs={"right":(1, 0), "left":(-1, 0), "up": (0, -1), "down": (0, 1)}

	process=Popen([prog], stdin=PIPE, stdout=PIPE)
	while True:
		move = process.stdout.readline()[:-1]
		if debug: print (x,y, move)

		if (x, y, move) in moves:
			print >> sys.stderr, "Repeat move"
			sys.exit(1)
		if move in dirs:
			newx=x+dirs[move][0]
			newy=y+dirs[move][1]
		elif move=="no exit":
			if has_exit==False:
				solved()
				break
			else:
				print >> sys.stderr, "There is an exit"
				sys.exit(1) 
		else:
			print >> sys.stderr, "Invalid move"
			sys.exit(1)

		moves.add((x, y, move))

		if maze[newy][newx]=="#":
			process.stdin.write('wall\n')
			process.stdin.flush()
		elif maze[newy][newx]=="X":
			solved()
			break
		else:
			x=newx
			y=newy
			process.stdin.write('ok\n')
			process.stdin.flush()