from crontab import CronTab
import re
from ..calls.create import Task
import logging


def post(task_id=None, period=None, user=None, force=False):
    """

        Change schedule of the given task

    Parameters
    ----------
    task_id: str
        Id of task to be change
    period: str
        Cron formatted schedule string
    user: str
        Task user

    Returns
    -------
    result: str
        result[0]: message
        result[1]: bool if it is deleted or not
    Notes
    -----
    % in any of string make script falls.

    Examples
    --------
    >>> # Change stopped task
    >>> import requests
    >>> import json
    >>> params = {"user": 'test', "task_id": '8485#&', "period": 'minute.every(1)'}
    >>> requests.post(url='<IP:PORT>/MG/routines/change', json=params)
        ['8485#& succesfully changed', True]

    >>> # Change started task
    >>> params = {"user": 'test', "task_id": '8485#&'}
    >>> requests.post(url='<IP:PORT>/MG/routines/change', json=params)
         ['8485#& succesfully stopped', True]
    >>> params = {"user": 'test', "task_id": '8485#&', "period": 'minute.every(1)'}
    >>> requests.post(url='<IP:PORT>/MG/routines/change', json=params)
         ['8485#& succesfully changed', True]

    >>> # Wrong task_id
    >>> params = {"user": 'test', "task_id": '0000000'}
    >>> requests.post(url='<IP:PORT>/MG/routines/change', json=params)
         ['Wrong task id. This task does not exists.', False]
    """
    period = period
    user = Task.clean_string(user)
    task_id = Task.clean_string(task_id)
    user_cron = CronTab(user=True)
    jobs = [job for job in user_cron.find_comment('{}:{}'.format(user, task_id))]
    if len(jobs) > 1:
        logging.warning('There are two task with the same id, {}.'.format(task_id))
        result = 'There are two task with the same id.'
    elif len(jobs) == 0:
        result = ['Wrong task id. This task does not exists.', False]
    else:
        job = jobs[0]
        eval('job.{}'.format(period))
        job.enable(True)
        user_cron.write()
        result = ['{} successfully changed'.format(task_id), True]

    return result