from couchdb import schema as from couchdb client import Server import

from couchdb import schema as s
from couchdb.client import Server

import settings

DB = None

class Manager(object):
    def __init__(self, cls):
        self.cls = cls
        self.type = cls.TYPE

    def all(self):
        args = {'type': self.type}
        mapf = """function(doc) { if (doc.type == '%(type)s') { emit(doc._id, doc); } }""" % args
        return DB.query(mapf)



class Model(s.Document):
    @classmethod
    def objects(cls):
        return Manager(cls)

    def __init__(self, *args, **kwargs):
        super(Model, self).__init__(*args, **kwargs)
        if not hasattr(self, 'TYPE'):
            raise Exception('Model subclass should provide TYPE class attribute')

    def save(self):
        self.store(DB)
        


def connect(db_name, force=False):
    global DB

    if DB is None or Force:
        server = Server('http://localhost:5984/')
        try:
            DB = server[db_name]
        except Exception:
            DB = create_db(db_name)
    return DB


def create_db(db_name, force=False):
    try:
        server.create(db_name)
    except Exception:
        if force:
            del server[db_name]
            server.create(db_name)
    return server[db_name]

connect(settings.DATABASE_NAME)