# ===============================================================================
# Copyright (C) 2010 Diego Duclos
#
# This file is part of eos.
#
# eos is free software: you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published by
# the Free Software Foundation, either version 2 of the License, or
# (at your option) any later version.
#
# eos is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with eos.  If not, see <http://www.gnu.org/licenses/>.
# ===============================================================================

import threading

from sqlalchemy import MetaData, create_engine
from sqlalchemy.orm import sessionmaker, scoped_session
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy import pool


import migration
from eos import config


class ReadOnlyException(Exception):
    pass


gamedata_connectionstring = config.gamedata_connectionstring
if callable(gamedata_connectionstring):
    gamedata_engine = create_engine("sqlite://", creator=gamedata_connectionstring, echo=config.debug)
else:
    gamedata_engine = create_engine(gamedata_connectionstring, echo=config.debug)

gamedata_meta = MetaData()
gamedata_meta.bind = gamedata_engine
gamedata_session = sessionmaker(bind=gamedata_engine, autoflush=False, expire_on_commit=False)()

# This should be moved elsewhere, maybe as an actual query. Current, without try-except, it breaks when making a new
# game db because we haven't reached gamedata_meta.create_all()
try:
    config.gamedata_version = gamedata_session.execute(
        "SELECT `field_value` FROM `metadata` WHERE `field_name` LIKE 'client_build'"
    ).fetchone()[0]
except:
    config.gamedata_version = None

saveddata_connectionstring = config.saveddata_connectionstring
if saveddata_connectionstring is not None:
    if callable(saveddata_connectionstring):
        saveddata_engine = create_engine(creator=saveddata_connectionstring, echo=config.debug)
    else:
        saveddata_engine = create_engine(saveddata_connectionstring, echo=config.debug)

    saveddata_meta = MetaData()
    saveddata_meta.bind = saveddata_engine
    saveddata_session = sessionmaker(bind=saveddata_engine, autoflush=False, expire_on_commit=False)()
else:
    saveddata_meta = None

# Lock controlling any changes introduced to session
sd_lock = threading.Lock()

# Import all the definitions for all our database stuff
from eos.db.gamedata import alphaClones, attribute, category, effect, group, icon, item, marketGroup, metaData, metaGroup, queries, traits, unit
from eos.db.saveddata import booster, cargo, character, crest, damagePattern, databaseRepair, drone, fighter, fit, implant, implantSet, loadDefaultDatabaseValues, miscData, module, override, price, queries, skill, targetResists, user

# Import queries
from eos.db.gamedata.queries import *
from eos.db.saveddata.queries import *

# If using in memory saveddata, you'll want to reflect it so the data structure is good.
if config.saveddata_connectionstring == "sqlite:///:memory:":
    saveddata_meta.create_all()


def rollback():
    with sd_lock:
        saveddata_session.rollback()