# corridors.py

# This script makes a random expert-sized .mbf board with corridors
# of lengths 1-MAX_CORRIDOR_LENGTH all around the border. The idea
# is you start in the top left and go right - down the right hand
# side - left across the bottom - then up the left hand side. The
# starts of each of these straights are always safe (except with the
# side ones you have to start on the 3rd square from the edge)
# If you play the boards prior knowledge it is a good test of
# reaction time since if you go too fast you always blast when you
# get to a mine!

import sys
import random

MAX_CORRIDOR_LENGTH = 7

class msboard:
   def __init__(self, width, height):
      self.width  = width
      self.height = height
      self.grid = [[0 for x in xrange(width)] for y in xrange(height)]
   def alter(self, x,y):
      if (0 <= x < self.width) and (0 <= y < self.height):
         self.grid[y][x] ^= 1
      else:
         print "Error. Out of range."
         return 0
   def display(self):
      for y in xrange(self.height):
         line = ""
         for val in self.grid[y]:
            if val: line += "m "
            else: line += ". "
         print line
   def mine_count(self):
      return sum([sum(row) for row in self.grid])
   def mbf(self):
      body = ""
      body += chr(self.width) + chr(self.height)
      mines = self.mine_count()
      body += chr(mines/2**8) + chr(mines%2**8)
      for y in xrange(self.height):
         for x in xrange(self.width):
            if self.grid[y][x] == 1: body += chr(x)+chr(y)
      if len(body) != 4+2*mines:
         print "Error! Invalid mbf format."
         return -1
      else: return body

def main():
   argv = sys.argv
   argc = len(argv)

   file_name = "corridor.mbf"

   my_board = msboard(30, 16)
   for i in xrange(my_board.width):
      my_board.alter(i,1)
      my_board.alter(i,my_board.height-2)
   for i in xrange(2,my_board.height-2):
      my_board.alter(1,i)
      my_board.alter(my_board.width-2,i)

   # rand mines around edge
   #top
   counter = 0
   while 1:
      counter += random.randint(1,MAX_CORRIDOR_LENGTH)
      if counter >= my_board.width: break
      my_board.alter(counter,0)
      counter += 1
   #rhs
   counter = 2
   while 1:
      counter += random.randint(1,MAX_CORRIDOR_LENGTH)
      if counter >= my_board.height-2: break
      my_board.alter(my_board.width-1,counter)
      counter += 1
   #bottom
   counter = 0
   while 1:
      counter += random.randint(1,MAX_CORRIDOR_LENGTH)
      if counter >= my_board.width: break
      my_board.alter(my_board.width-1-counter,my_board.height-1)
      counter += 1
   #lhs
   counter = 2
   while 1:
      counter += random.randint(1,MAX_CORRIDOR_LENGTH)
      if counter >= my_board.height-2: break
      my_board.alter(0,my_board.height-1-counter)
      counter += 1


   file_obj = open(file_name, 'wb')
   file_obj.write(my_board.mbf())
   file_obj.close()

if __name__ == "__main__":
   main()