webgo/goban.py

#!/usr/bin/python

"""
the main file for WebGo.
"""
import sys,string
import cgi
import pickle
import psql,helper

picklefile = "goban.pickledump"

###############################################################################



def display_goban(goban):
	"""
	gets: dictionary containing the layout of the used goban.
	returns: string containing the HTML code for a clickable goban.
	"""
	data = ""

	hoshis19x19 = [(4,4),(4,10),(4,16),(10,4),(10,10),(10,16),(16,4),(16,10),(16,16)]
	hoshis13x13 = [(4,4),(4,10),(7,7),(10,4),(10,10)]
	hoshis9x9 = [(3,3),(3,7),(5,5),(7,3),(7,7)]
	
	
	data += '<form method="post">'
	try:
		size = goban["size"]
	except:
		#TODO: proper error management
		raise "[EE] display_goban: got broken goban dictionary."
		sys.exit(1)
	for x in range(1,size+1):
		for y in range(1,size+1):
			# check for white or black stone
			if goban[(x,y)] == 1:
				stone = "_white"
			elif goban[(x,y)] == 2:					
				stone = "_black"
			else:
				stone = ""
			sx = str(x)
			sy = str(y)
			# check position:
			if (x == 1) and (y == 1): # upper left
				data += '<input type=image src="img/topleftline'+stone+'.png" name="('+sx+','+sy+')">'
			elif (x == 1) and (y == size): # upper right
				data += '<input type=image src="img/toprightline'+stone+'.png" name="('+sx+','+sy+')"><br>'
			elif (x == size) and (y == size): # lower right
				data += '<input type=image src="img/bottomrightline'+stone+'.png" name="('+sx+','+sy+')"><br>'	
			elif (x == size) and (y == 1): # lower left
				data += '<input type=image src="img/bottomleftline'+stone+'.png" name="('+sx+','+sy+')">'
			elif (y == 1): #left line
				data += '<input type=image src="img/leftline'+stone+'.png" name="('+sx+','+sy+')">'
			elif (x == 1): # top line
				data += '<input type=image src="img/topline'+stone+'.png" name="('+sx+','+sy+')">'
			elif (y == size): # right line
				data += '<input type=image src="img/rightline'+stone+'.png" name="('+sx+','+sy+')"><br>'
			elif (x == size): #bottom line 
				data += '<input type=image src="img/bottomline'+stone+'.png" name="('+sx+','+sy+')">'
			else: # hoshi or empty inner field
				defaultfield = '<input type=image src="img/centerline'+stone+'.png" name="('+sx+','+sy+')">'
				#too lazy to make special images for hoshi fields with stones:
				if goban[(x,y)] == 1:
					hoshifield = '<input type=image src="img/centerline_white.png" name="('+sx+','+sy+')">'
				elif goban[(x,y)] == 2:
					hoshifield = '<input type=image src="img/centerline_black.png" name="('+sx+','+sy+')">'
				else: #empty hoshi
					hoshifield = '<input type=image src="img/hoshi.png" name="('+sx+','+sy+')">'			
				if size == 19: # 9 hoshis
					if (x,y) in hoshis19x19:
						data += hoshifield
					else:
						data += defaultfield
				elif size == 13:
					if (x,y) in hoshis13x13:
						data += hoshifield
					else:
						data += defaultfield
				elif size == 9:
					if (x,y) in hoshis9x9:
						data += hoshifield
					else:
						data += defaultfield
	data += '</form>'		
	return data





def string_to_tuple(str):
	"""
	gets a string. If the string contains '(',')' and ',', then return
	a tuple processed from the string. If the partial string is empty, then 
	-1 will be returned for that value.
	"""
	if (str[0] =='(') and (str[-1] ==')') and (string.find(str,',')):
		splitlist = string.split(str[1:-1],",")
		returnlist = []
		for item in splitlist:
			try:
				returnlist.append(int(item))
			except: #empty string
				returnlist.append(-1)
		return tuple(returnlist)
				
		
def process_form(goban):
	"""
	gets a goban dictionary.
	
	reads out the returned CGI form.
	if the goban has been clicked, return a (x,y) tuple of the position.
	
	"""
	#get instance of fieldstorage
	form = cgi.FieldStorage()
	#if form == empty (which means if page is displayed for the first time):
	if form.keys() != []:
		#cut out the name of the clicked button
		namestring =  string.split(form.keys()[0],".x")[0]
		position =  string_to_tuple(namestring)
		ret = set_stone(goban, position)
		if (type(ret) == type("")):
			return (goban,ret) #return old goban and error string
		else:
			goban = ret
	return (goban,"") # return new goban and empty string
			
		
def set_stone(goban, position):
	"""gets a goban dictionary and a (x,y)-tuple. Returns a modified goban."""
	turn = goban["turn_number"]
	if (goban[position] == 0): #empty field
		goban[position] = (turn % 2) + 1 #even turn: white tone (1), else black stone(2)
		goban["turn_number"] += 1
		#now write changed values to database
		psql.update_goban_field(goban["name"],position[0],position[1],(turn % 2) + 1)
		psql.update_turn_number(goban["name"],goban["turn_number"])
		return goban
	else:
		return "Could not make move: Field not empty."
			
###############################################################################

def main():
	# Print the required header that tells the browser how to render the text.
	#(currently done by error logger)
	#print "Content-Type: text/plain\n\n"
	
	#do stuff
	data = 	helper.header()

	#read goban table from database
	tmplist = psql.read_table("test")
	#make a dictionary out of the list
	goban = psql.fetchall_list_to_goban_dict(tmplist)
	#print goban

	(goban,str) = process_form(goban)
	data += "<p> Turn number: %s, %s Player's Move.</p>" % (goban["turn_number"],("White","Black")[goban["turn_number"] % 2]) #eleet ;>
	data += display_goban(goban)
	if str != "":
		data +="\n<p>"+str+"</p>\n"

	
	data += helper.footer()
	print data