#!flask/bin/python
#compares app.db to app/models
import imp
from migrate.versioning import api
from app import db
from config import SQLALCHEMY_DATABASE_URI
from config import SQLALCHEMY_MIGRATE_REPO
#set the location for version 
v = api.db_version(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO)
#gets new version number
migration = SQLALCHEMY_MIGRATE_REPO + ('/versions/%03d_migration.py' % (v+1))

tmp_module = imp.new_module('old_model')
#creates model?
old_model = api.create_model(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO)
#executes the two modules
exec(old_model, tmp_module.__dict__)

script = api.make_update_script_for_model(SQLALCHEMY_DATABASE_URI, 
					SQLALCHEMY_MIGRATE_REPO,
					tmp_module.meta, db.metadata)
#opens the new version template then writes the update into it
open(migration, "wt").write(script)
api.upgrade(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO)
v = api.db_version(SQLALCHEMY_DATABASE_URI, SQLALCHEMY_MIGRATE_REPO)
print('New migration saved as ' + migration)
print('Current database version: ' + str(v))

