import helper,gnugo
import pgdb,sys,time

DEBUG = 1

dbusername="webgouser"
dbpassword="webgopassword"
dbname="webgo"



#pgdb.connect(connect_string) -> connection
#connect_string = 'host:database:user:password:opt:tty'
connect_string='localhost:'+dbname+':'+dbusername+':'+dbpassword
db=pgdb.connect(connect_string)

################# table creation and removal #######################################################################
def create_table(name,layout=""):
	"""
	create_table(name:string, layout:string)
	returns name if successfull, None if not.
	
	
	simple function to create a table. the function itself would just
	create an empty table with the command 'CREATE TABLE ();'.
	The real layout is given to the function as an argument of type 
	string. This string contains all column declarations in SQL syntax:
	"var1	real, var2	int"
	name is the name of the table
	
	"""
	executestring = "CREATE TABLE %s ( %s );" % (name,layout)
	sql_one_liner(executestring)

def create_goban_table(player1,player2,size,description=""):
	"""
	gets:player1, player2, size of goban.
	creates postgresql table containing goban data.
	returns: name of created table.
	
	the table looks like this:
	line 			x1 
	turn_number
	size
	name
	description
	player1
	player2
	sgf
	created
	lastmove
	
	and the meaning of these fields:
	(turn_number,x1) is the current turn,
	(size,x1) is the length of a side of the goban,
	(name,x1) is the name of this goban.
	(description,x1) is the user-given name of this goban.
	(player1,x1) is the name of one player.
	(player2,x1) is the name of the other player.
	(sgf,x1) contains a sgf file with the current board.
	(created,x1) is the time of creation of the table
	(lastmove,x1) is the time of the last player move
	"""
	tablename = helper.generate_game_name()
	data="line text, x1 text"
	create_table(tablename,data)
	#now insert additional variables
	insert_into_table(tablename,strtuple("turn_number","1"))
	#size of goban
	insert_into_table(tablename,strtuple("size",size))
	#name of goban (=name of table in database)
	insert_into_table(tablename,strtuple("name",tablename))
	#description of goban (=user-given name)
	insert_into_table(tablename,strtuple("description",description))
	#name of player1 
	insert_into_table(tablename,strtuple("player1",player1))
	#name of player2 
	insert_into_table(tablename,strtuple("player2",player2))
	#empty sgf file as string
	sgf = gnugo.create_sgf_file(size)
	insert_into_table(tablename,strtuple("sgf",sgf))
	#time of creation
	insert_into_table(tablename,strtuple("created",str(int(time.time()))))
	#time of last move
	insert_into_table(tablename,strtuple("lastmove",str(int(time.time()))))

	return tablename

def strtuple(s1,s2):
	"""
	creating a string looking like a tuple.
	gets 2 strings.
	useful for inserting something into a table.
	"""
	tmplist = []
	tmplist.append(s1)
	tmplist.append(s2)
	return str(tuple(tmplist))

def create_user_table():
	"""
	creates a table named users with following columns:
	name - name of user
	password - passsword of user
	game1 - the 10 game slots of this user contain names
	...      of goban tables
	game10
	sessionid - id of current session
	timeout -  when does session time out?
	"""
	data = "username varchar(15)"
	data += ", password text"
	for i in range(1,11):
		data += ", game"+str(i)+" text"
	data += ", sessionid text"
	data += ", timeout int"
	create_table("users",data)

def drop_table(name):
	"""
	gets: name of table.
	executes DROP TABLE <name>
	"""
	executestring = "DROP TABLE %s;" % (name)
	sql_one_liner(executestring)



################# generic functions ############################################################################

def insert_into_table(table, content):
	"""
	gets the name of a table and a content string.
	executes INSERT INTO name VALUES content;
	"""
	executestring = "INSERT INTO %s VALUES %s" % (table,content)
	sql_one_liner(executestring)
	
	
def sql_one_liner(data):
	"""
	gets:SQL statement
	creates a cursor, executes <statement>, closes cursor.
	"""
	cursor=db.cursor()
	cursor.execute(data)
	# Commit the changes 	
	db.commit()
	cursor.close()

def read_table(table):
	"""
	gets the name of a table, does a 
	SELECT * FROM table;
	returns output.
	"""
	cursor=db.cursor()
	data="SELECT * FROM %s;" % (table)
	cursor.execute(data)
	# Commit the changes 	
	db.commit()
	ret = cursor.fetchall()
	cursor.close()
	return ret



def update_database_field(table,column,new_value,uniqname,uniqvalue):
	"""
	wrapper for SQL UPDATE.
	gets:	table name
			name of column containing field to be updated
			new value of field in column
			name of unique identifier and
			value of unique identifier for field (e.g. 'username' and 'testuser')
	"""
	if new_value == "":
		executestring ="UPDATE %s SET %s = DEFAULT WHERE %s = '%s'" % (table,column,uniqname,uniqvalue)
	else:
		executestring ="UPDATE %s SET %s = '%s' WHERE %s = '%s'" % (table,column,new_value,uniqname,uniqvalue)
	sql_one_liner(executestring)

################# access of users table #####################################################################

def get_user_game_list(name):
	"""
	gets a username, returns the list of games for user.
	"""
	cursor=db.cursor()
	ret = []
	for x in range(1,11):
		data="SELECT game%s FROM users WHERE username = '%s'" % (x,name)
		try:
			cursor.execute(data)
			# Commit the changes 	
			db.commit()
			ret.append(cursor.fetchone()[0]) #[0], because return is a list
		except:
			ret = "could not get info of all games -- table corrupt?"
	cursor.close()
	return ret

def get_user_info(name,infotype):
	"""
	gets the name of a user and the type of requested info.
	returns info from database.
	"""
	cursor=db.cursor()
	if infotype in ("password","sessionid","timeout"):
		
		data="SELECT %s FROM users WHERE username = '%s'" % (infotype,name)
		try:
			cursor.execute(data)
			# Commit the changes 	
			db.commit()
			ret = cursor.fetchone()[0]
		except:
			ret = "no such user"
		cursor.close()
	else:
		ret = "Are your sure about the infotype?"
	return ret

def set_user_sessionid(username,sessionid):
	"""
	gets username and sessionid, writes sessid into database
	"""
	update_users_table_field(username,"sessionid",sessionid)

def set_user_timeout(username,timeout=None):
	"""
	gets username, sets timeout to time.time + 30min
	"""
	import time
	if timeout == None:
		timeout = int(time.time()) + 900 #current time in seconds + seconds for session
	update_users_table_field(username,"timeout",timeout)

def update_users_table_field(username,column,new_value):
	"""
	gets: username,column name, new content for field in column.
	executes an update_database_field with uniqname = "username"
	"""
	update_database_field("users",column,new_value,"username",username)


def delete_user(username):
	"""
	gets username.
	deletes user from database.
	"""
	#TODO: delete all games of user before delting user?
	executestring ="DELETE FROM users WHERE username='%s'" %(username)
	sql_one_liner(executestring)
	return executestring




def add_webgo_user(name,password):
	"""
	adds a database entry for a user.
	gets: username and password
	"""
	#size of goban
	tmplist=[]
	tmplist.append(name)
	tmplist.append(password)
	insert_into_table("users",str(tuple(tmplist)))	

def get_users_with_free_game_slots():
	"""
	gets nothing.
	returns a list of all users who have at least one game slot free.
	"""
	cursor=db.cursor()
	data = """select username from users where 
	(game1 IS NULL) OR (game2 IS NULL) OR (game3 IS NULL) OR 
	(game4 IS NULL) OR (game5 IS NULL) OR (game6 IS NULL) OR 
	(game7 IS NULL) OR (game8 IS NULL) OR (game9 IS NULL) OR 
	(game10 IS NULL)"""
	cursor.execute(data)
	# Commit the changes 	
	db.commit()
	tmplist = cursor.fetchall()
	ret = [item[0] for item in tmplist]
	return ret	

def get_free_game_slot(username):
	"""
	gets a username
	returns the name of a free game slot or "" if none found.
	"""
	ret = ""
	for i in range(1,11):
		cursor=db.cursor()
		data = "SELECT username FROM users WHERE username='%s' AND game%i IS NULL" % (username,i)
		cursor.execute(data)
		# Commit the changes 	
		db.commit()
		tmp = [item[0] for item in cursor.fetchall()]
		if (tmp != []):
			ret = "game"+str(i)
	return ret


def set_game_slot(username,gameslot,gamename):
	"""
	gets username,game slot,game name.
	sets the game slot for user username to game name ;>
	"""
	if (gamename == "") or (gamename == None) or (gamename == "NULL") :
		executestring ="UPDATE users SET %s = DEFAULT WHERE username = '%s'" %(gameslot, username)
	else:
		executestring ="UPDATE users SET %s = '%s' WHERE username = '%s'" %(gameslot,gamename, username)
	sql_one_liner(executestring)




################# access of goban tables ####################################################################

def get_players_for_game(tablename):
	"""
	gets the name of a goban table, returns player1 and player2 as tuple.
	"""
	cursor=db.cursor()
	data="select x1 from %s where line='player1' OR line='player2';" % (tablename)
	cursor.execute(data)
	# Commit the changes 	
	db.commit()
	players = [item[0] for item in cursor.fetchall()]
	cursor.close()
	return tuple(players)


def update_goban_table_field(table,column,line,new_value):
	"""
	gets: table name, column name, line name, new content for field.
	executes an update_database_field with uniqname = "line"
	"""
	update_database_field(table,column,new_value,"line",line)

def update_turn_number(table,new_number):
	"""
	gets: name of table,new turn number
	modifies 'turn_number' in table
	"""
	update_goban_table_field(table,"x1","turn_number",new_number)

def get_sgf(table):
	"""
	gets a table name,
	returns content of "sgf" field.
	"""
	cursor=db.cursor()
	data="select x1 from %s where line='sgf';" % (table)
	cursor.execute(data)
	# Commit the changes 	
	db.commit()
	sgf = cursor.fetchone()[0]
	cursor.close()
	return sgf

def get_description(table):
	"""
	gets table name,
	returns content of "description" field.
	"""
	cursor=db.cursor()
	data="select x1 from %s where line='description';" % (table)
	cursor.execute(data)
	# Commit the changes 	
	db.commit()
	sgf = cursor.fetchone()[0]
	cursor.close()
	return sgf


def fetchall_list_to_goban_dict(list):
	"""
	gets the output from read_table (a list),
	returns a goban dictionary.
	"""
	#create dictionary
	ret = {}
	#get size of goban
	for item in list:
		if item[0] == "size":
			size=int(item[1])
			ret["size"] = size
	#populate dictionary with goban field
	for item in list:
		if item[0][0] == "y": #goban fields
			#get current y coordinate
			y = int(item[0][1:])
			#fill dictionary for current y coordinate
			for x in range(1,size+1):
				ret[(x,y)]=helper.check_for_int(item[x])
		else: #other variables
			ret[item[0]]=helper.check_for_int(item[1])
	return ret


def get_time(table,whichtime):
	"""
	gets:
	- a table name,
	- a string equal "created" or "lastmove".
	returns either the time of creation or the time of the last player move for
	the table, depending of whichtime.
	"""
	cursor=db.cursor()
	data="select x1 from %s where line='%s';" % (table,whichtime)
	cursor.execute(data)
	# Commit the changes 	
	db.commit()
	try:
		time = int(cursor.fetchone()[0])
	except:
		time = None
	cursor.close()
	return time

def set_time(tablename):
	"""
	gets name of goban table, sets lastmove to current time.
	"""
	update_goban_table_field(tablename,"x1","lastmove",int(time.time()))



def test():
	#create_table("test")
	drop_table("test")
	create_goban_table(9)
	update_goban_table_field("test","x1","turn_number",4)
	list = read_table("test")
	print list
	dict = fetchall_list_to_goban_dict(list)
	print dict
	print dict["turn_number"]
	print dict["name"]
	print type(dict["turn_number"])
	


#test()