"""Garcon tasks and utils for Feed Ingestion workflows."""

from datetime import date as date_module
import sys

from decorator import decorator
from garcon_contrib.dynamo_feed_status import garcon_feed_status

from feed_ingestion.util import task_status

STOP_RESPONSE = {'stop': True}


def _resolve_arg_values(func, args, feed_name, required_arg_names):
    """Dynamically resolve argument values.

    Takes function arguments and resolves required arguments' values.
    If `feed_name` is not specified
    we will try to resolve it from arguments as well.
    Function arguments should match `required_arg_names`,
    otherwise exception will be raised.

    Args:
        func (func): Function.
        args (tuple): Function arguments.
        feed_name (str): Feed name.
        required_arg_names (list): Required arguments list.

    Returns:
        list: List with resolved values.
    """
    if feed_name:
        resolved_values = [feed_name]
    else:
        required_arg_names.append('feed_name')
        resolved_values = []
    orig_func_arg_names = (
        func.__code__.co_varnames[:func.__code__.co_argcount])
    for req_arg_name in reversed(required_arg_names):
        if req_arg_name in orig_func_arg_names:
            value = args[orig_func_arg_names.index(req_arg_name)]
            resolved_values.insert(0, value)
        else:
            raise Exception('Argument not provided: %s', req_arg_name)
    return resolved_values


def assert_valid_str_bool(value):
    """Assert that value is a valid string boolean.

    It should be either 'True' or 'False'.

    Args:
        value (str): Value.

    Returns:
        str: validated value.
    """
    if value not in ['True', 'False']:
        raise ValueError(f'Invalid boolean value: "{value}"')
    return value


def check_status(feed_name=None, task_id=None):
    """Check DynamoDB status.

    We expect that some of the wrapped function args are: activity and date.
    If `feed_name` is not specified we will try to resolve it dynamically
    from arguments as well. The names should be exactly:
        activity, date, feed_name.
    Otherwise an exception will be raised.

    Args:
        feed_name (str): Feed name.
        task_id (str): Task id.

    Returns:
        func: Decorated task function.
    """
    @decorator
    def wrapper(orig_func, *args, **kwargs):
        resolved_values = _resolve_arg_values(
            orig_func, args, feed_name, ['activity', 'date'])

        activity, date, effect_feed_name = resolved_values

        effect_task_id = task_id or orig_func.__name__

        if task_status.is_completed_task(
                effect_feed_name, date, effect_task_id):
            activity.logger.info(
                'feed: {feed_name} task: {task_id} '
                'date: {date} status: COMPLETE'.format(
                    feed_name=effect_feed_name, task_id=effect_task_id,
                    date=date))
            return

        result = orig_func(*args, **kwargs)

        if result and result.get('stop') is True:
            return result
        else:
            task_status.mark_completed_task(
                effect_feed_name, date, effect_task_id)
            activity.logger.info(
                'feed: {feed_name} task: {task_id} '
                'date: {date} status: COMPLETE'.format(
                    feed_name=effect_feed_name, task_id=effect_task_id,
                    date=date))

            return result

    return wrapper


def check_ingested_status(
        feed_name=None,
        skip_check=getattr(sys, '_called_from_test', False)):
    """Check INGESTED status.

    Check if flow for some date has been already ingested.

    Args:
        feed_name (str): Feed name.
        skip_check (bool): Skip check.

    Returns:
        func: Decorated task function.
    """

    @decorator
    def wrapper(orig_func, *args, **kwargs):
        if skip_check:
            return orig_func(*args, **kwargs)

        date, effect_feed_name = _resolve_arg_values(
            orig_func, args, feed_name, ['date'])
        date = date or date_module.today().strftime('%Y-%m-%d')

        overall_status = garcon_feed_status.get_overall_status(
            effect_feed_name, date)

        if overall_status == garcon_feed_status.STATUS_INGESTED:
            return STOP_RESPONSE

        return orig_func(*args, **kwargs)

    return wrapper