import os
import sys
import transaction
from zope.app.appsetup import database, config
from zope.app.publication.zopepublication import ZopePublication
from waeup.kofa.app import University

#: The name under which any artificially created University instance
#: will be put into the root folder
APP_NAME = 'stress_app'

def open_zodb(instance_path=''):
    """Open a ZODB and configure it using a site.zcml file.

    If `instance_path` is not given, we assume to be in the root of
    some Zope instance and compute relative paths to
    'parts/etc/site.zcml' and 'var/filestorage/Data.fs'.

    If `instance_path` is given, these paths are os.path.joined with
    it.

    Returns a tuple containing a database object, an open connection
    to this DB and the root folder.
    """
    config_file = os.path.join(
        instance_path, 'parts', 'etc', 'site.zcml')
    zodb_file = os.path.join(
        instance_path, 'var', 'filestorage', 'Data.fs')
    print "WAEUP.STRESS: configuring ZODB from %s / %s" % (
        config_file, zodb_file)
    context = config(config_file)
    db = database(zodb_file)
    conn = db.open()
    root = conn.root()
    root_folder = root.get(ZopePublication.root_name, None)
    return db, conn, root_folder

def close_zodb(db):
    print "WAEUP.STRESS: closing ZODB"
    transaction.commit() # make sure changes are saved
    db.close()
    return

def zodb(func):
    """A decorator that does a ZODB setup and calls the decorated
    function with the ZODB root folder as first argument.
    """
    def wrapped(*args, **kw):
        instance_path = kw.get('instance_path', '')
        db, conn, root_folder = open_zodb(instance_path)
        try:
            func(root_folder, *args, **kw)
        finally:
            close_zodb(db)
    return wrapped

@zodb
def create_app(root_folder):
    """Create a University instance named 'stress_app' in ZODB.

    The `root_folder` arg is injected by the decorator and represents
    the root folder of an opened, writable ZODB.
    """
    print [x for x in root_folder]
    root_folder['stress_app'] = University()
    print "WAEUP.STRESS.SCRIPTS: created 'stress_app' in root folder."
    return

create_app()