MediaMath/t1-python

# -*- coding: utf-8 -*-
"""Provides field type conversion functions T1 data classes."""

from datetime import datetime
from terminalone.utils import FixedOffset
import re


def int_to_bool(value):
    """Convert integer string {"0","1"} to its corresponding bool"""
    try:
        return bool(int(value))
    except ValueError:
        raise TypeError('must supply integer string')


def none_to_empty(val):
    """Convert None to empty string.

    Necessary for fields that are required POST but have no logical value.
    """
    if val is None:
        return ""
    return val


def enum(all_vars, default):
    """Check input against accepted set or return a default."""

    def get_value(test_value):
        if test_value in all_vars:
            return test_value
        else:
            return default

    return get_value


def default_empty(default):
    """Check an input against its falsy value or return a default."""

    def get_value(test_value):
        if test_value:
            return test_value
        else:
            return default

    return get_value


def strpt(dt_string):
    """Convert ISO string time to datetime.datetime. No-op on datetimes"""
    # 2016-11-07T09:07:57
    # 2016-11-07T09:07:57+0000
    # 2016-11-16T12:31:10+00:00
    offset_re = re.compile('([-+][0-9:]+$)')
    if isinstance(dt_string, datetime):
        return dt_string
    if dt_string == 'now':
        return datetime.now()

    matches = re.split(offset_re, dt_string)
    dt_string = matches[0]
    if len(matches) > 1:
        offset_str = matches[1].replace(':', '')
        offset = int(offset_str[-4:-2]) * 60 + int(offset_str[-2:])
        if offset_str[0] == "-":
            offset = -offset
    else:
        offset = 0

    return datetime.strptime(dt_string, "%Y-%m-%dT%H:%M:%S").replace(tzinfo=FixedOffset(offset))


def strft(dt_obj, null_on_none=False, offset=False):
    """Convert datetime.datetime to ISO string.

    :param null_on_none: bool Occasionally, we will actually want to send an
        empty string where a datetime would typically go. For instance, if a
        strategy has an end_date set, but then wants to change to use
        campaign end date, the POST will normally omit the end_date field
        (because you cannot send it with use_campaign_end).
        However, this will cause an error because there was an end_date set
        previously. So, we need to send an empty string to indicate that it
        should be nulled out. In cases like this, null_on_none should be set
        to True in the entity's _push dict using a partial to make it a
        single-argument function. See strategy.py
    :param offset: bool Whether to add the timezone offset
    :raise AttributeError: if not provided a datetime
    :return: str
    """

    try:
        dt_str = dt_obj.strftime("%Y-%m-%dT%H:%M:%S")
        if offset:
            dt_str += dt_obj.strftime("%z")
        return dt_str
    except AttributeError:
        if dt_obj is None and null_on_none:
            return ""
        raise


def float_or_none(value, null_on_none=False):
    if value is not None:
        if isinstance(value, int):
            value = float(value)
        if not isinstance(value, float):
            raise TypeError('must supply float')
        return value
    else:
        if null_on_none:
            return ""
        else:
            raise TypeError('must supply float')


def int_or_none(value, null_on_none=False):
    if value is not None:
        if not isinstance(value, int):
            raise TypeError('must supply int')
        return value
    else:
        if null_on_none:
            return ""
        else:
            raise TypeError('must supply int')


class Deleted:
    """used for when un-setting a field"""

    def __init__(self, original_value):
        self.original_value = original_value

    @staticmethod
    def get_value():
        return ""

    def get_original_value(self):
        return self.original_value