#!/usr/bin/env python

import os

import boto.s3
import json
import swiftclient
from boto import config as botoconfig
from boto.exception import S3CreateError
from boto.s3.connection import S3Connection, OrdinaryCallingFormat
from oauth2client.service_account import ServiceAccountCredentials
from gcloud.storage.client import Client
from gcloud import exceptions
from azure.storage.blob import BlobService

def bucket_exists(conn, name):
    bucket = conn.lookup(name)
    if not bucket:
        return False
    return True

bucket_name = os.getenv('BUCKET_NAME')
region = os.getenv('AWS_REGION')

if os.getenv('DATABASE_STORAGE') == "s3":
    conn = boto.s3.connect_to_region(region)
    if not bucket_exists(conn, bucket_name):
        try:
            conn.create_bucket(bucket_name, location=region)
        except S3CreateError as err:
            # try again in the default S3 region before giving up
            default_region = 'us-east-1'
            if region != default_region:
                print('Failed to create bucket in {}, trying default region {}...'.format(
                    region, default_region))
                conn = boto.s3.connect_to_region(default_region)
                if not bucket_exists(conn, bucket_name):
                    conn.create_bucket(bucket_name, location=default_region)
                # TODO: if we got here, somehow we need to propagate "us-east-1"
                # into WALE_S3_ENDPOINT...

elif os.getenv('DATABASE_STORAGE') == "gcs":
    scopes = ['https://www.googleapis.com/auth/devstorage.full_control']
    credentials = ServiceAccountCredentials.from_json_keyfile_name(os.getenv('GOOGLE_APPLICATION_CREDENTIALS'), scopes=scopes)
    with open(os.getenv('GOOGLE_APPLICATION_CREDENTIALS')) as data_file:
        data = json.load(data_file)
    conn = Client(credentials=credentials, project=data['project_id'])
    exists = True
    try:
        conn.get_bucket(bucket_name)
    except exceptions.NotFound:
        exists = False
    except:
        raise
    if not exists:
        conn.create_bucket(bucket_name)

elif os.getenv('DATABASE_STORAGE') == "azure":
    conn = BlobService(account_name=os.getenv('WABS_ACCOUNT_NAME'), account_key=os.getenv('WABS_ACCESS_KEY'))
    #It doesn't throw an exception if the container exists by default(https://github.com/Azure/azure-storage-python/blob/master/azure/storage/blob/baseblobservice.py#L504).
    conn.create_container(bucket_name)

elif os.getenv('DATABASE_STORAGE') == "swift":
    conn = swiftclient.Connection(
        user=os.getenv('SWIFT_USER'),
        key=os.getenv('SWIFT_PASSWORD'),
        authurl=os.getenv('SWIFT_AUTHURL'),
        auth_version=os.getenv('SWIFT_AUTH_VERSION'),
        tenant_name=os.getenv('SWIFT_TENANT')
    )
    # swift also does not throw exception if container already exists.
    conn.put_container(os.getenv('BUCKET_NAME'))

else:
    botoconfig.add_section('s3')
    botoconfig.set('s3', 'use-sigv4', 'True')
    botoconfig.add_section('Boto')
    botoconfig.set('Boto', 'is_secure', 'False')
    conn = S3Connection(
        host=os.getenv('S3_HOST'),
        port=int(os.getenv('S3_PORT')),
        calling_format=OrdinaryCallingFormat())
    # HACK(bacongobbler): allow boto to connect to minio by changing the region name for s3v4 auth
    conn.auth_region_name = os.getenv('AWS_REGION')
    if not bucket_exists(conn, bucket_name):
        conn.create_bucket(bucket_name)