# Path: bitsd/persistence/engine.py
# @contextmanager
# def session_scope():
#     """Provide a transactional scope around a series of operations."""
#     session = Session()
#     try:
#         yield session
#         session.commit()
#     except IntegrityError as e:
#         LOG.error("Integrity error in DB, rolling back: %s", e)
#         session.rollback()
#     except:
#         LOG.error("Error in DB, rolling back.")
#         session.rollback()
#         raise
#     finally:
#         session.close()
# 
# Path: bitsd/persistence/models.py
# class Status(Base):
#     """Representation of a logged status change."""
#     __tablename__ = 'Status'
#     __table_args__ = {'mysql_engine': 'InnoDB', 'mysql_charset': 'utf8mb4'}
# 
#     OPEN = 'open'
#     CLOSED = 'closed'
#     AWAY = 'away'
# 
#     timestamp = Column(DateTime, primary_key=True, default=datetime.now)
#     value = Column(
#         Enum(OPEN, CLOSED, AWAY),
#         nullable=False
#     )
#     modified_by = Column(Enum('BITS', 'web'), nullable=False)
# 
#     def __init__(self, value, modified_by):
#         self.value = value
#         self.modified_by = modified_by
# 
#     def __str__(self):
#         return 'Status {.value}'.format(self)
# 
#     def jsondict(self, wrap=True):
#         """Return a JSON-serializable dictionary representing the object"""
#         data = {
#             "timestamp": self.timestamp.isoformat(' '),
#             "modifiedby": self.modified_by,
#             "value": self.value
#         }
#         if wrap:
#             return {'status': data}
#         else:
#             return data


from bitsd.persistence.engine import session_scope
from bitsd.persistence.models import Status
from sqlalchemy import asc
    def __init__(self, resolution=30, samples_cont=5000):
        if self.resolution_is_invalid(resolution):
            raise self.InvalidResolutionError()

        self.samples_count = samples_cont
        self.ticks_per_hour = 60 / resolution
        self.minutes_per_tick = resolution

    def forecast(self):
        #TODO caching
        return self.calculate_frequencies()

    def calculate_frequencies(self):
        samples = self.get_samples()
        buckets = self.count_presence_per_slot(samples)
        return self.normalize(buckets)

    def count_presence_per_slot(self, samples):
        buckets = self.init_buckets()

        # TODO algorithm here

        return buckets

    def init_buckets(self):
        return [[0] * (24 * self.ticks_per_hour) for i in range(7)]

    def get_samples(self):
        with session_scope() as session:
            samples = session \

# Path: bitsd/persistence/engine.py
# @contextmanager
# def session_scope():
#     """Provide a transactional scope around a series of operations."""
#     session = Session()
#     try:
#         yield session
#         session.commit()
#     except IntegrityError as e:
#         LOG.error("Integrity error in DB, rolling back: %s", e)
#         session.rollback()
#     except:
#         LOG.error("Error in DB, rolling back.")
#         session.rollback()
#         raise
#     finally:
#         session.close()
# 
# Path: bitsd/persistence/models.py
# class Status(Base):
#     """Representation of a logged status change."""
#     __tablename__ = 'Status'
#     __table_args__ = {'mysql_engine': 'InnoDB', 'mysql_charset': 'utf8mb4'}
# 
#     OPEN = 'open'
#     CLOSED = 'closed'
#     AWAY = 'away'
# 
#     timestamp = Column(DateTime, primary_key=True, default=datetime.now)
#     value = Column(
#         Enum(OPEN, CLOSED, AWAY),
#         nullable=False
#     )
#     modified_by = Column(Enum('BITS', 'web'), nullable=False)
# 
#     def __init__(self, value, modified_by):
#         self.value = value
#         self.modified_by = modified_by
# 
#     def __str__(self):
#         return 'Status {.value}'.format(self)
# 
#     def jsondict(self, wrap=True):
#         """Return a JSON-serializable dictionary representing the object"""
#         data = {
#             "timestamp": self.timestamp.isoformat(' '),
#             "modifiedby": self.modified_by,
#             "value": self.value
#         }
#         if wrap:
#             return {'status': data}
#         else:
#             return data


# Path: bitsd/server/presence.py
from bitsd.persistence.engine import session_scope
from bitsd.persistence.models import Status
from sqlalchemy import asc

    def __init__(self, resolution=30, samples_cont=5000):
        if self.resolution_is_invalid(resolution):
            raise self.InvalidResolutionError()

        self.samples_count = samples_cont
        self.ticks_per_hour = 60 / resolution
        self.minutes_per_tick = resolution

    def forecast(self):
        #TODO caching
        return self.calculate_frequencies()

    def calculate_frequencies(self):
        samples = self.get_samples()
        buckets = self.count_presence_per_slot(samples)
        return self.normalize(buckets)

    def count_presence_per_slot(self, samples):
        buckets = self.init_buckets()

        # TODO algorithm here

        return buckets

    def init_buckets(self):
        return [[0] * (24 * self.ticks_per_hour) for i in range(7)]

    def get_samples(self):
        with session_scope() as session:
            samples = session \

                .query(Status.timestamp, Status.value) \