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#
#ein orm
#noch laengst nit fertig
#
#die erste spalte einer tabelle muss die primary key sein!!
#

#import cherrypy as ch
import sqlite3

conn = sqlite3.connect(':memory:')
def debug():
	while True:
		print eval(raw_input('>>>'))

#class cursor:
#	@staticmethod
#	def execute(*args):
#		print args


def cursor2result_objects(find, cursor):
	return [find(i[0]) for i in cursor.fetchall()] #die methode find wird erst in der methode fusion "hinzugefuegt"
def cursor2plain(cursor):
	return cursor.fetchone()[0]

class BasicSQLQueries(object):
	def __init__(self, primary_key_name, table_name):
		self.primary_key = primary_key_name
		self.table_name = table_name

	def exe(self, *args):
		query = args[0].replace('*table*', self.table_name).replace('*primary_key*', self.primary_key)
		print 'EXECUTING:', query, args[1:]
		cursor = conn.cursor() #conn muss vorgegeben sein
		cursor.execute(query, args[1:])
		return cursor

	def all(self):
		return cursor2result_objects(cursor=self.exe("SELECT *primary_key* FROM *table*"), find=self.find)
		
class BasicSQLResult(object):
	def __init__(self, QueryObject, primary_key, create):
		self.QueryObject = QueryObject
		self.primary_key = primary_key
		if create:
			self.QueryObject.exe('INSERT INTO *table* (*primary_key*) VALUES (?)', self.primary_key)
	def __getitem__(self, item):
		return cursor2plain(self.QueryObject.exe('SELECT ? FROM *table* WHERE *primary_key*=?', item, self.primary_key))
	def __setitem__(self, item, value):
		return self.update(**{item: value})
		#KLAPPT NICH self.QueryObject.exe('UPDATE *table* SET ? = ? WHERE *primary_key* = ?', item, value, self.primary_key)
	def update(self, **data):
		arg = data.values()
		arg.append(self.primary_key)
		self.QueryObject.exe('UPDATE *table* SET ' + ''.join([key + ' = ?, ' for key in data])[:-2] + ' WHERE *primary_key*=?', *arg)# why is foo(1, *t, 6) invalid?


		
def fusion(QueryObject, ResultClass):
	class Tmp(QueryObject):
		def __init__(self):
			QueryObject.__init__(self)
		def create(self, primary_key_val):
			return ResultClass(QueryObject=self, primary_key=primary_key_val, create=True)
		def find(self, primary_key_val):#exactly like create but did not create the row
			return ResultClass(QueryObject=self, primary_key=primary_key_val, create=False)
	return Tmp()

#==========================TEST================		


conn.cursor().execute('''CREATE TABLE users
(nickname char(50),
firstname char(50),
lastname char(50),
age int)''')
class UsersResult(BasicSQLResult):
	def __init__(self, **kw):
		BasicSQLResult.__init__(self, **kw)
	def write_post(self, text):
		post = Posts.create('foo goes bike')
		post['text'] = text
class UsersQueries(BasicSQLQueries):
	def __init__(self):
		BasicSQLQueries.__init__(self, primary_key_name='nickname', table_name='users')
	def bla(self):
		self.exe('FROM users do bullshit AND FUCK SQL')
Users = fusion(UsersQueries, UsersResult)



horst = Users.create('Horst')
horst['lastname'] = 'Allendorf'

a_user = Users.all()[0]
print a_user.QueryObject.exe('SELECT * FROM *table* where *primary_key*=?', a_user.primary_key).fetchone() #hat funktional kein sinn, gibt aber ein guten einblick

print horst['lastname'] #-> "lastname"  (WTF?)
print horst['X'] #-> "X" (und warum kein  ``OperationalError``?)

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C:\Dokumente und Einstellungen\sc>"C:\Dokumente und Einstellungen\sc\Desktop\ira
e\domino.py"
EXECUTING: INSERT INTO users (nickname) VALUES (?) ('Horst',)
EXECUTING: UPDATE users SET lastname = ? WHERE nickname=? ('Allendorf', 'Horst')

EXECUTING: SELECT nickname FROM users ()
EXECUTING: SELECT * FROM users where nickname=? (u'Horst',)
(u'Horst', None, u'Allendorf', None)
EXECUTING: SELECT ? FROM users WHERE nickname=? ('lastname', 'Horst')
lastname
EXECUTING: SELECT ? FROM users WHERE nickname=? ('X', 'Horst')
X

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("SELECT ? FROM users WHERE nickname=?" ('X', 'Horst'))

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$ wc -l `find sqlalchemy-0.4.0beta3 -regex '.*py$' -printf '%p '`
[...]
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