"""
Django settings for talerbank.

For more information on this file, see
https://docs.djangoproject.com/en/1.9/topics/settings/

For the full list of settings and their values, see
https://docs.djangoproject.com/en/1.9/ref/settings/
"""

import base64
import logging
import os
import re
import sys
import urllib.parse
from .talerconfig import TalerConfig, ConfigurationError

LOGGER = logging.getLogger(__name__)

LOGGER.info("DJANGO_SETTINGS_MODULE: %s" \
            % os.environ.get("DJANGO_SETTINGS_MODULE"))

TC = TalerConfig.from_file(os.environ.get("TALER_CONFIG_FILE"))

# Build paths inside the project like this:
# os.path.join(BASE_DIR, ...)
BASE_DIR = os.path.dirname(
    os.path.dirname(os.path.abspath(__file__)))

# Quick-start development settings - unsuitable for production
# See https://docs.djangoproject.com/en/1.9/howto/deployment/checklist/


SECRET_KEY = os.environ.get("TALER_BANK_SECRET_KEY", None)

if not SECRET_KEY:
    LOGGER.info("secret key not configured in"
                " TALER_BANK_SECRET_KEY env variable,"
                " generating random secret")
    SECRET_KEY = base64.b64encode(os.urandom(32)).decode('utf-8')

# SECURITY WARNING: don't run with debug turned on in production!

if "demo" == os.environ.get("TALER_ENV_NAME"):
    DEBUG = False
else:
    DEBUG = True

ADMIN_ENABLED = False

ALLOWED_HOSTS = ["*"]

LOGIN_URL = "login"

LOGIN_REDIRECT_URL = "index"


# Application definition

INSTALLED_APPS = [
    'django.contrib.auth',
    'django.contrib.contenttypes',
    'django.contrib.sessions',
    'django.contrib.messages',
    'django.contrib.staticfiles',
    'talerbank.app'
]

MIDDLEWARE = [
    'django.middleware.security.SecurityMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.middleware.common.CommonMiddleware',
    'django.middleware.csrf.CsrfViewMiddleware',
    'django.contrib.auth.middleware.AuthenticationMiddleware',
    'django.contrib.sessions.middleware.SessionMiddleware',
    'django.contrib.messages.middleware.MessageMiddleware',
    'django.middleware.clickjacking.XFrameOptionsMiddleware',
    'talerbank.app.middleware.ExceptionMiddleware',
]

TEMPLATES = [
    {'BACKEND': 'django.template.backends.jinja2.Jinja2',
     'DIRS': [os.path.join(BASE_DIR,
                           "talerbank/app/static/web-common/"),
              os.path.join(BASE_DIR,
                           "talerbank/app/templates")],
     'OPTIONS': {
         'environment': 'talerbank.jinja2.environment'}}]

# Disable those, since they don't work with
# jinja2 anyways.
TEMPLATE_CONTEXT_PROCESSORS = []

WSGI_APPLICATION = 'talerbank.wsgi.application'


# Database
# https://docs.djangoproject.com/en/1.9/ref/settings/#databases

DATABASES = {}

DBNAME = TC.value_string("bank", "database", required=True)
DBNAME = os.environ.get("TALER_BANK_ALTDB", DBNAME)

if not DBNAME:
    raise Exception("DB not specified (neither in config or as" \
                    "cli argument)")

LOGGER.info("dbname: %s" % DBNAME)

CHECK_DBSTRING_FORMAT = re.search(
    r"[a-z]+:///[a-z]+([\?][a-z]+=[a-z/]+)?", DBNAME)
if not CHECK_DBSTRING_FORMAT:
    LOGGER.error("Bad db string given '%s', respect the format" \
                 "'dbtype:///dbname'" % DBNAME)
    sys.exit(2)

DBCONFIG = {}
# Maybe trust the parsing from urlparse?
DB_URL = urllib.parse.urlparse(DBNAME)

if DB_URL.scheme not in ("postgres") or DB_URL.scheme == "":
    LOGGER.error("DB '%s' is not supported" % DB_URL.scheme)
    sys.exit(1)
if DB_URL.scheme == "postgres":
    DBCONFIG["ENGINE"] = 'django.db.backends.postgresql_psycopg2'
    DBCONFIG["NAME"] = DB_URL.path.lstrip("/")

if not DB_URL.netloc:
    P = urllib.parse.parse_qs(DB_URL.query)
    if ("host" not in P) or P["host"] == "":
        HOST = None
    else:
        HOST = P["host"][0]
else:
    HOST = DB_URL.netloc

if HOST:
    DBCONFIG["HOST"] = HOST # Sockets directory.

DATABASES["default"] = DBCONFIG

# Password validation
# https://docs.djangoproject.com/en/1.9/ref/settings/#auth-password-validators

AUTH_PASSWORD_VALIDATORS = [
    {'NAME': 'django.contrib.auth.password_validation' \
             '.UserAttributeSimilarityValidator'},
    {'NAME': 'django.contrib.auth.password_validation' \
             '.MinimumLengthValidator'},
    {'NAME': 'django.contrib.auth.password_validation' \
             '.CommonPasswordValidator'},
    {'NAME': 'django.contrib.auth.password_validation' \
             '.NumericPasswordValidator'}]


# Internationalization
# https://docs.djangoproject.com/en/1.9/topics/i18n/

LANGUAGE_CODE = 'en-us'

TIME_ZONE = 'UTC'

USE_I18N = True

USE_L10N = True

##
# Set to False to silence this error:
# https://stackoverflow.com/questions/18622007/runtimewarning-datetimefield-received-a-naive-datetime
USE_TZ = False

# Static files (CSS, JavaScript, Images)
# https://docs.djangoproject.com/en/1.9/howto/static-files/

STATIC_URL = '/static/'

STATICFILES_DIRS = [
    os.path.join(BASE_DIR, "talerbank/app/static"),
    os.path.join(BASE_DIR, "talerbank/app/static/web-common"),
]

STATIC_ROOT = '/tmp/talerbankstatic/'
ROOT_URLCONF = "talerbank.app.urls"

try:
    TALER_CURRENCY = TC.value_string(
        "taler", "currency", required=True)
except ConfigurationError as exc:
    LOGGER.error(exc)
    sys.exit(3)

TALER_MAX_DEBT = TC.value_string(
    "bank", "MAX_DEBT",
    default="%s:50.0" % TALER_CURRENCY)
TALER_MAX_DEBT_BANK = TC.value_string(
    "bank", "MAX_DEBT_BANK",
    default="%s:0.0" % TALER_CURRENCY)

TALER_DIGITS = TC.value_int(
    "bank", "NDIGITS", default=2)
# Order matters
TALER_PREDEFINED_ACCOUNTS = [
    'Bank', 'Exchange', 'Tor', 'GNUnet',
    'Taler', 'FSF', 'Tutorial', 'Survey']
TALER_EXPECTS_DONATIONS = [
    'Tor', 'GNUnet', 'Taler', 'FSF']
TALER_SUGGESTED_EXCHANGE = TC.value_string(
    "bank", "suggested_exchange")