from sqlalchemy import create_engine, Column, Integer, String, DateTime, Text, Index, ForeignKey
from sqlalchemy.ext.declarative import declarative_base
from sqlalchemy.orm import sessionmaker, relation, backref
from sqlalchemy.orm.exc import NoResultFound
from sqlalchemy.exc import IntegrityError
from sqlalchemy.sql import and_
import settings, os, mimetypes

engine = create_engine(settings.db_path)

Base = declarative_base(bind = engine)

class User(Base):
	__tablename__ = 'users'

	id = Column(Integer, primary_key = True)
	username = Column(String, unique = True, index = True)
	password = Column(String)
	files = relation('File', backref = 'user', order_by = 'File.date.desc()')

	def __init__(self, username, password):
		self.username = username
		self.password = password

class File(Base):
	__tablename__ = 'files'

	id = Column(Integer, primary_key = True)
	hash = Column(String, unique = True, index = True)
	file_hash = Column(String, unique = True, index = True)
	filename = Column(String)
	date = Column(DateTime)
	user_id = Column(Integer, ForeignKey('users.id'), nullable = True)

	def __init__(self, hash, file_hash, filename, date, user_id = None):
		self.hash = hash
		self.file_hash = file_hash
		self.filename = filename
		self.date = date
		self.user_id = user_id

	@staticmethod
	def pretty_size(size):
		suffixes = (('B', 2**10), ('KiB', 2**20), ('MiB', 2**30), ('GiB', 2**40), ('TiB', 2**50))
		for suf, lim in suffixes:
			if size > lim:
				continue
			else:
				return '%s %s' % (str(round(size/float(lim/2**10), 2)), suf)

	def get_path(self):
		return os.path.join(settings.file_directory, self.hash + os.path.splitext(self.filename)[1])

	def html(self):
		return u'<a href="/f/{hash}/{filename}">{filename}</a> <sup><a href="/f/{hash}">1</a> <a href="/f/{hash}{ext}">2</a></sup> ({size}) on {date}'.format(
			hash = self.hash, filename = self.filename, ext = os.path.splitext(self.filename)[1],
			size = self.pretty_size(os.path.getsize(self.get_path())), date = self.date.strftime('%Y-%m-%d %H:%M:%S UTC'))

	def get_mime_type(self):
		return mimetypes.guess_type(self.filename, strict = False)[0] or 'application/octet-stream'

	def is_image(self):
		return self.get_mime_type().startswith('image')

	def image_html(self):
		return u'<a href="/f/{hash}{ext}" title="{filename}"><img src="/t/{hash}" alt="{filename}" /></a>'.format(
			hash = self.hash, filename = self.filename, ext = os.path.splitext(self.filename)[1])

Base.metadata.create_all()
Session = sessionmaker(bind = engine, autoflush = True, autocommit = False)