"""
Other validators
================

Collection of validators that require more functionality than JSON Schema.
"""

from ows_accounting import response
from ows_accounting.constants import error
from ows_accounting.constants import header
from ows_accounting.logic import period


def validate_periods(request):
    """Checks given periods are active.

    Args:
        request (Flask.request): the request.

    Returns:
        response.Response: On success, a list of periods in the DB.
            On error, code and message corresponding to error triggered.
    """

    # Check if passed account type is valid
    account_id, account_type = get_account_info_from_request(request)

    response_account_type = validate_account_type(account_type)

    if not response_account_type:
        return response_account_type

    # Check if account type is present in DB or has periods associated with it
    response_available_periods = period.get_available_periods(
        account_id, account_type)

    if not response_available_periods:
        return response_available_periods

    # Check if periods from DB correspond to request
    db_periods = sorted(response_available_periods.message)

    request_periods = get_period_from_request(request)

    if db_periods and request_periods in ','.join(
            map(str, db_periods)):
        return response.Response(message=db_periods)

    return response.create_error_response(
        code=error.ERROR_CODE_INVALID_REQUEST,
        message=error.ERROR_MESSAGE_INVALID_PERIOD)


def validate_account_type(account_type):
    """Checks if account type for DynamoDB lookup is valid.

        Args:
            account_type (str): Input value to check.

        Returns:
            response.Response: Returns status 200 and account type on success.
    """

    if account_type not in [
        header.GRASS_ACCOUNT_TYPE_VENDOR,
            header.GRASS_ACCOUNT_TYPE_SUBACCOUNT]:

        message = '{error} {account_type}'.format(
            error=error.ERROR_MESSAGE_INVALID_ACCOUNT,
            account_type=account_type)

        return response.create_error_response(
            code=error.ERROR_CODE_INVALID_REQUEST,
            message=message)

    return response.Response(message=account_type)


def get_period_from_request(request):
    """Gets period from request args or body.

        Args:
            request (Flask.request): the request.

        Returns:
            request_period(str): Retrieved period.
    """

    if request.method == 'POST':
        data = request.get_json()
        request_period = data.get('periods')
    else:
        request_period = request.args.get('periods', '')
        request_period = ','.join(sorted(request_period.split(',')))

    return request_period


def get_account_info_from_request(request):
    """Gets account info from request header or args.

        Args:
            request (Flask.request): the request.

        Returns:
            account_id, account_type(tuple): Retrieved account info.
    """

    account_id = request.headers.get(
        header.GRASS_ACCOUNT_ID) or request.args.get('account_id')
    account_type = request.headers.get(
        header.GRASS_ACCOUNT_TYPE) or request.args.get('account_type')

    return account_id, account_type