frappe/frappe/utils/data.py

# Copyright (c) 2015, Frappe Technologies Pvt. Ltd. and Contributors
# MIT License. See license.txt

from __future__ import unicode_literals

import frappe
import operator
import json
import re, datetime, math, time
from six.moves.urllib.parse import quote, urljoin
from six import iteritems, text_type, string_types, integer_types
from frappe.desk.utils import slug

DATE_FORMAT = "%Y-%m-%d"
TIME_FORMAT = "%H:%M:%S.%f"
DATETIME_FORMAT = DATE_FORMAT + " " + TIME_FORMAT


def is_invalid_date_string(date_string):
	# dateutil parser does not agree with dates like "0001-01-01" or "0000-00-00"
	return (not date_string) or (date_string or "").startswith(("0001-01-01", "0000-00-00"))

# datetime functions
def getdate(string_date=None):
	"""
	Converts string date (yyyy-mm-dd) to datetime.date object.
	If no input is provided, current date is returned.
	"""
	from dateutil import parser
	from dateutil.parser._parser import ParserError

	if not string_date:
		return get_datetime().date()
	if isinstance(string_date, datetime.datetime):
		return string_date.date()

	elif isinstance(string_date, datetime.date):
		return string_date

	if is_invalid_date_string(string_date):
		return None
	try:
		return parser.parse(string_date).date()
	except ParserError:
		frappe.throw(frappe._('{} is not a valid date string.').format(
			frappe.bold(string_date)
		), title=frappe._('Invalid Date'))

def get_datetime(datetime_str=None):
	from dateutil import parser

	if datetime_str is None:
		return now_datetime()

	if isinstance(datetime_str, (datetime.datetime, datetime.timedelta)):
		return datetime_str

	elif isinstance(datetime_str, (list, tuple)):
		return datetime.datetime(datetime_str)

	elif isinstance(datetime_str, datetime.date):
		return datetime.datetime.combine(datetime_str, datetime.time())

	if is_invalid_date_string(datetime_str):
		return None

	try:
		return datetime.datetime.strptime(datetime_str, DATETIME_FORMAT)
	except ValueError:
		return parser.parse(datetime_str)

def to_timedelta(time_str):
	from dateutil import parser

	if isinstance(time_str, string_types):
		t = parser.parse(time_str)
		return datetime.timedelta(hours=t.hour, minutes=t.minute, seconds=t.second, microseconds=t.microsecond)

	else:
		return time_str

def add_to_date(date, years=0, months=0, weeks=0, days=0, hours=0, minutes=0, seconds=0, as_string=False, as_datetime=False):
	"""Adds `days` to the given date"""
	from dateutil import parser
	from dateutil.parser._parser import ParserError
	from dateutil.relativedelta import relativedelta

	if date==None:
		date = now_datetime()

	if hours:
		as_datetime = True

	if isinstance(date, string_types):
		as_string = True
		if " " in date:
			as_datetime = True
		try:
			date = parser.parse(date)
		except ParserError:
			frappe.throw(frappe._("Please select a valid date filter"), title=frappe._("Invalid Date"))

	date = date + relativedelta(years=years, months=months, weeks=weeks, days=days, hours=hours, minutes=minutes, seconds=seconds)

	if as_string:
		if as_datetime:
			return date.strftime(DATETIME_FORMAT)
		else:
			return date.strftime(DATE_FORMAT)
	else:
		return date

def add_days(date, days):
	return add_to_date(date, days=days)

def add_months(date, months):
	return add_to_date(date, months=months)

def add_years(date, years):
	return add_to_date(date, years=years)

def date_diff(string_ed_date, string_st_date):
	return (getdate(string_ed_date) - getdate(string_st_date)).days

def month_diff(string_ed_date, string_st_date):
	ed_date = getdate(string_ed_date)
	st_date = getdate(string_st_date)
	return (ed_date.year - st_date.year) * 12 + ed_date.month - st_date.month + 1

def time_diff(string_ed_date, string_st_date):
	return get_datetime(string_ed_date) - get_datetime(string_st_date)

def time_diff_in_seconds(string_ed_date, string_st_date):
	return time_diff(string_ed_date, string_st_date).total_seconds()

def time_diff_in_hours(string_ed_date, string_st_date):
	return round(float(time_diff(string_ed_date, string_st_date).total_seconds()) / 3600, 6)

def now_datetime():
	dt = convert_utc_to_user_timezone(datetime.datetime.utcnow())
	return dt.replace(tzinfo=None)

def get_timestamp(date):
	return time.mktime(getdate(date).timetuple())

def get_eta(from_time, percent_complete):
	diff = time_diff(now_datetime(), from_time).total_seconds()
	return str(datetime.timedelta(seconds=(100 - percent_complete) / percent_complete * diff))

def _get_time_zone():
	return frappe.db.get_system_setting('time_zone') or 'Asia/Kolkata' # Default to India ?!

def get_time_zone():
	if frappe.local.flags.in_test:
		return _get_time_zone()

	return frappe.cache().get_value("time_zone", _get_time_zone)

def convert_utc_to_timezone(utc_timestamp, time_zone):
	from pytz import timezone, UnknownTimeZoneError
	utcnow = timezone('UTC').localize(utc_timestamp)
	try:
		return utcnow.astimezone(timezone(time_zone))
	except UnknownTimeZoneError:
		return utcnow

def get_datetime_in_timezone(time_zone):
	utc_timestamp = datetime.datetime.utcnow()
	return convert_utc_to_timezone(utc_timestamp, time_zone)

def convert_utc_to_user_timezone(utc_timestamp):
	time_zone = get_time_zone()
	return convert_utc_to_timezone(utc_timestamp, time_zone)

def now():
	"""return current datetime as yyyy-mm-dd hh:mm:ss"""
	if frappe.flags.current_date:
		return getdate(frappe.flags.current_date).strftime(DATE_FORMAT) + " " + \
			now_datetime().strftime(TIME_FORMAT)
	else:
		return now_datetime().strftime(DATETIME_FORMAT)

def nowdate():
	"""return current date as yyyy-mm-dd"""
	return now_datetime().strftime(DATE_FORMAT)

def today():
	return nowdate()

def get_abbr(string, max_len=2):
	abbr=''
	for part in string.split(' '):
		if len(abbr) < max_len and part:
			abbr += part[0]

	return abbr or '?'

def nowtime():
	"""return current time in hh:mm"""
	return now_datetime().strftime(TIME_FORMAT)

def get_first_day(dt, d_years=0, d_months=0, as_str=False):
	"""
	 Returns the first day of the month for the date specified by date object
	 Also adds `d_years` and `d_months` if specified
	"""
	dt = getdate(dt)

	# d_years, d_months are "deltas" to apply to dt
	overflow_years, month = divmod(dt.month + d_months - 1, 12)
	year = dt.year + d_years + overflow_years

	return datetime.date(year, month + 1, 1).strftime(DATE_FORMAT) if as_str else datetime.date(year, month + 1, 1)

def get_quarter_start(dt, as_str=False):
	date = getdate(dt)
	quarter = (date.month - 1) // 3 + 1
	first_date_of_quarter = datetime.date(date.year, ((quarter - 1) * 3) + 1, 1)
	return first_date_of_quarter.strftime(DATE_FORMAT) if as_str else first_date_of_quarter

def get_first_day_of_week(dt, as_str=False):
	dt = getdate(dt)
	date = dt - datetime.timedelta(days=dt.weekday())
	return date.strftime(DATE_FORMAT) if as_str else date

def get_year_start(dt, as_str=False):
	dt = getdate(dt)
	date = datetime.date(dt.year, 1, 1)
	return date.strftime(DATE_FORMAT) if as_str else date

def get_last_day_of_week(dt):
	dt = get_first_day_of_week(dt)
	return dt + datetime.timedelta(days=6)

def get_last_day(dt):
	"""
	 Returns last day of the month using:
	 `get_first_day(dt, 0, 1) + datetime.timedelta(-1)`
	"""
	return get_first_day(dt, 0, 1) + datetime.timedelta(-1)

def get_quarter_ending(date):
	date = getdate(date)

	# find the earliest quarter ending date that is after
	# the given date
	for month in (3, 6, 9, 12):
		quarter_end_month = getdate('{}-{}-01'.format(date.year, month))
		quarter_end_date = getdate(get_last_day(quarter_end_month))
		if date <= quarter_end_date:
			date = quarter_end_date
			break

	return date

def get_year_ending(date):
	''' returns year ending of the given date '''
	date = getdate(date)
	# first day of next year (note year starts from 1)
	date = add_to_date('{}-01-01'.format(date.year), months = 12)
	# last day of this month
	return add_to_date(date, days=-1)

def get_time(time_str):
	from dateutil import parser

	if isinstance(time_str, datetime.datetime):
		return time_str.time()
	elif isinstance(time_str, datetime.time):
		return time_str
	else:
		if isinstance(time_str, datetime.timedelta):
			time_str = str(time_str)
		return parser.parse(time_str).time()

def get_datetime_str(datetime_obj):
	if isinstance(datetime_obj, string_types):
		datetime_obj = get_datetime(datetime_obj)
	return datetime_obj.strftime(DATETIME_FORMAT)

def get_date_str(date_obj):
	if isinstance(date_obj, string_types):
		date_obj = get_datetime(date_obj)
	return date_obj.strftime(DATE_FORMAT)

def get_time_str(timedelta_obj):
	if isinstance(timedelta_obj, string_types):
		timedelta_obj = to_timedelta(timedelta_obj)

	hours, remainder = divmod(timedelta_obj.seconds, 3600)
	minutes, seconds = divmod(remainder, 60)
	return "{0}:{1}:{2}".format(hours, minutes, seconds)

def get_user_date_format():
	"""Get the current user date format. The result will be cached."""
	if getattr(frappe.local, "user_date_format", None) is None:
		frappe.local.user_date_format = frappe.db.get_default("date_format")

	return frappe.local.user_date_format or "yyyy-mm-dd"

get_user_format = get_user_date_format  # for backwards compatibility

def get_user_time_format():
	"""Get the current user time format. The result will be cached."""
	if getattr(frappe.local, "user_time_format", None) is None:
		frappe.local.user_time_format = frappe.db.get_default("time_format")

	return frappe.local.user_time_format or "HH:mm:ss"

def format_date(string_date=None, format_string=None):
	"""Converts the given string date to :data:`user_date_format`
	User format specified in defaults

	Examples:

	* dd-mm-yyyy
	* mm-dd-yyyy
	* dd/mm/yyyy
	"""
	import babel.dates
	from babel.core import UnknownLocaleError

	if not string_date:
		return ''

	date = getdate(string_date)
	if not format_string:
		format_string = get_user_date_format()
	format_string = format_string.replace("mm", "MM")
	try:
		formatted_date = babel.dates.format_date(
			date, format_string,
			locale=(frappe.local.lang or "").replace("-", "_"))
	except UnknownLocaleError:
		format_string = format_string.replace("MM", "%m").replace("dd", "%d").replace("yyyy", "%Y")
		formatted_date = date.strftime(format_string)
	return formatted_date

formatdate = format_date  # For backwards compatibility

def format_time(time_string=None, format_string=None):
	"""Converts the given string time to :data:`user_time_format`
	User format specified in defaults

	Examples:

	* HH:mm:ss
	* HH:mm
	"""
	import babel.dates
	from babel.core import UnknownLocaleError

	if not time_string:
		return ''

	time_ = get_time(time_string)
	if not format_string:
		format_string = get_user_time_format()
	try:
		formatted_time = babel.dates.format_time(
			time_, format_string,
			locale=(frappe.local.lang or "").replace("-", "_"))
	except UnknownLocaleError:
		formatted_time = time_.strftime("%H:%M:%S")
	return formatted_time

def format_datetime(datetime_string, format_string=None):
	"""Converts the given string time to :data:`user_datetime_format`
	User format specified in defaults

	Examples:

	* dd-mm-yyyy HH:mm:ss
	* mm-dd-yyyy HH:mm
	"""
	import babel.dates
	from babel.core import UnknownLocaleError

	if not datetime_string:
		return

	datetime = get_datetime(datetime_string)
	if not format_string:
		format_string = (
			get_user_date_format().replace("mm", "MM")
			+ ' ' + get_user_time_format())

	try:
		formatted_datetime = babel.dates.format_datetime(datetime, format_string, locale=(frappe.local.lang or "").replace("-", "_"))
	except UnknownLocaleError:
		formatted_datetime = datetime.strftime('%Y-%m-%d %H:%M:%S')
	return formatted_datetime

def format_duration(seconds, hide_days=False):
	"""Converts the given duration value in float(seconds) to duration format

	example: converts 12885 to '3h 34m 45s' where 12885 = seconds in float
	"""

	seconds = cint(seconds)

	total_duration = {
		'days': math.floor(seconds / (3600 * 24)),
		'hours': math.floor(seconds % (3600 * 24) / 3600),
		'minutes': math.floor(seconds % 3600 / 60),
		'seconds': math.floor(seconds % 60)
	}

	if hide_days:
		total_duration['hours'] = math.floor(seconds / 3600)
		total_duration['days'] = 0

	duration = ''
	if total_duration:
		if total_duration.get('days'):
			duration += str(total_duration.get('days')) + 'd'
		if total_duration.get('hours'):
			duration += ' ' if len(duration) else ''
			duration += str(total_duration.get('hours')) + 'h'
		if total_duration.get('minutes'):
			duration += ' ' if len(duration) else ''
			duration += str(total_duration.get('minutes')) + 'm'
		if total_duration.get('seconds'):
			duration += ' ' if len(duration) else ''
			duration += str(total_duration.get('seconds')) + 's'

	return duration

def duration_to_seconds(duration):
	"""Converts the given duration formatted value to duration value in seconds

	example: converts '3h 34m 45s' to 12885 (value in seconds)
	"""
	validate_duration_format(duration)
	value = 0
	if 'd' in duration:
		val = duration.split('d')
		days = val[0]
		value += cint(days) * 24 * 60 * 60
		duration = val[1]
	if 'h' in duration:
		val = duration.split('h')
		hours = val[0]
		value += cint(hours) * 60 * 60
		duration = val[1]
	if 'm' in duration:
		val = duration.split('m')
		mins = val[0]
		value += cint(mins) * 60
		duration = val[1]
	if 's' in duration:
		val = duration.split('s')
		secs = val[0]
		value += cint(secs)

	return value

def validate_duration_format(duration):
	import re
	is_valid_duration = re.match("^(?:(\d+d)?((^|\s)\d+h)?((^|\s)\d+m)?((^|\s)\d+s)?)$", duration)
	if not is_valid_duration:
		frappe.throw(frappe._("Value {0} must be in the valid duration format: d h m s").format(frappe.bold(duration)))

def get_weekdays():
	return ['Monday', 'Tuesday', 'Wednesday', 'Thursday', 'Friday', 'Saturday', 'Sunday']

def get_weekday(datetime=None):
	if not datetime:
		datetime = now_datetime()
	weekdays = get_weekdays()
	return weekdays[datetime.weekday()]

def get_timespan_date_range(timespan):
	today = nowdate()
	date_range_map = {
		"last week": lambda: (get_first_day_of_week(add_to_date(today, days=-7)), get_last_day_of_week(add_to_date(today, days=-7))),
		"last month": lambda: (get_first_day(add_to_date(today, months=-1)), get_last_day(add_to_date(today, months=-1))),
		"last quarter": lambda: (get_quarter_start(add_to_date(today, months=-3)), get_quarter_ending(add_to_date(today, months=-3))),
		"last 6 months": lambda: (get_quarter_start(add_to_date(today, months=-6)), get_quarter_ending(add_to_date(today, months=-3))),
		"last year": lambda: (get_year_start(add_to_date(today, years=-1)), get_year_ending(add_to_date(today, years=-1))),
		"yesterday": lambda: (add_to_date(today, days=-1),) * 2,
		"today": lambda: (today, today),
		"tomorrow": lambda: (add_to_date(today, days=1),) * 2,
		"this week": lambda: (get_first_day_of_week(today), today),
		"this month": lambda: (get_first_day(today), today),
		"this quarter": lambda: (get_quarter_start(today), today),
		"this year": lambda: (get_year_start(today), today),
		"next week": lambda: (get_first_day_of_week(add_to_date(today, days=7)), get_last_day_of_week(add_to_date(today, days=7))),
		"next month": lambda: (get_first_day(add_to_date(today, months=1)), get_last_day(add_to_date(today, months=1))),
		"next quarter": lambda: (get_quarter_start(add_to_date(today, months=3)), get_quarter_ending(add_to_date(today, months=3))),
		"next 6 months": lambda: (get_quarter_start(add_to_date(today, months=3)), get_quarter_ending(add_to_date(today, months=6))),
		"next year": lambda: (get_year_start(add_to_date(today, years=1)), get_year_ending(add_to_date(today, years=1))),
	}

	if timespan in date_range_map:
		return date_range_map[timespan]()

def global_date_format(date, format="long"):
	"""returns localized date in the form of January 1, 2012"""
	import babel.dates

	date = getdate(date)
	formatted_date = babel.dates.format_date(date, locale=(frappe.local.lang or "en").replace("-", "_"), format=format)
	return formatted_date

def has_common(l1, l2):
	"""Returns truthy value if there are common elements in lists l1 and l2"""
	return set(l1) & set(l2)

def cast_fieldtype(fieldtype, value):
	if fieldtype in ("Currency", "Float", "Percent"):
		value = flt(value)

	elif fieldtype in ("Int", "Check"):
		value = cint(value)

	elif fieldtype in ("Data", "Text", "Small Text", "Long Text",
		"Text Editor", "Select", "Link", "Dynamic Link"):
		value = cstr(value)

	elif fieldtype == "Date":
		value = getdate(value)

	elif fieldtype == "Datetime":
		value = get_datetime(value)

	elif fieldtype == "Time":
		value = to_timedelta(value)

	return value

def flt(s, precision=None):
	"""Convert to float (ignoring commas in string)

		:param s: Number in string or other numeric format.
		:param precision: optional argument to specify precision for rounding.
		:returns: Converted number in python float type.

		Returns 0 if input can not be converted to float.

		Examples:

		>>> flt("43.5", precision=0)
		44
		>>> flt("42.5", precision=0)
		42
		>>> flt("10,500.5666", precision=2)
		10500.57
		>>> flt("a")
		0.0
	"""
	if isinstance(s, string_types):
		s = s.replace(',','')

	try:
		num = float(s)
		if precision is not None:
			num = rounded(num, precision)
	except Exception:
		num = 0.0

	return num

def cint(s, default=0):
	"""Convert to integer

		:param s: Number in string or other numeric format.
		:returns: Converted number in python integer type.

		Returns default if input can not be converted to integer.

		Examples:
		>>> cint("100")
		100
		>>> cint("a")
		0

	"""
	try:
		return int(float(s))
	except Exception:
		return default

def floor(s):
	"""
	A number representing the largest integer less than or equal to the specified number

	Parameters
	----------
	s : int or str or Decimal object
		The mathematical value to be floored

	Returns
	-------
	int
		number representing the largest integer less than or equal to the specified number

	"""
	try: num = cint(math.floor(flt(s)))
	except: num = 0
	return num

def ceil(s):
	"""
	The smallest integer greater than or equal to the given number

	Parameters
	----------
	s : int or str or Decimal object
		The mathematical value to be ceiled

	Returns
	-------
	int
		smallest integer greater than or equal to the given number

	"""
	try: num = cint(math.ceil(flt(s)))
	except: num = 0
	return num

def cstr(s, encoding='utf-8'):
	return frappe.as_unicode(s, encoding)

def rounded(num, precision=0):
	"""round method for round halfs to nearest even algorithm aka banker's rounding - compatible with python3"""
	precision = cint(precision)
	multiplier = 10 ** precision

	# avoid rounding errors
	num = round(num * multiplier if precision else num, 8)

	floor_num = math.floor(num)
	decimal_part = num - floor_num

	if not precision and decimal_part == 0.5:
		num = floor_num if (floor_num % 2 == 0) else floor_num + 1
	else:
		if decimal_part == 0.5:
			num = floor_num + 1
		else:
			num = round(num)

	return (num / multiplier) if precision else num

def remainder(numerator, denominator, precision=2):
	precision = cint(precision)
	multiplier = 10 ** precision

	if precision:
		_remainder = ((numerator * multiplier) % (denominator * multiplier)) / multiplier
	else:
		_remainder = numerator % denominator

	return flt(_remainder, precision)

def safe_div(numerator, denominator, precision=2):
	"""
	SafeMath division that returns zero when divided by zero.
	"""
	precision = cint(precision)

	if denominator == 0:
		_res = 0.0
	else:
		_res = float(numerator) / denominator

	return flt(_res, precision)

def round_based_on_smallest_currency_fraction(value, currency, precision=2):
	smallest_currency_fraction_value = flt(frappe.db.get_value("Currency",
		currency, "smallest_currency_fraction_value", cache=True))

	if smallest_currency_fraction_value:
		remainder_val = remainder(value, smallest_currency_fraction_value, precision)
		if remainder_val > (smallest_currency_fraction_value / 2):
			value += smallest_currency_fraction_value - remainder_val
		else:
			value -= remainder_val
	else:
		value = rounded(value)

	return flt(value, precision)

def encode(obj, encoding="utf-8"):
	if isinstance(obj, list):
		out = []
		for o in obj:
			if isinstance(o, text_type):
				out.append(o.encode(encoding))
			else:
				out.append(o)
		return out
	elif isinstance(obj, text_type):
		return obj.encode(encoding)
	else:
		return obj

def parse_val(v):
	"""Converts to simple datatypes from SQL query results"""
	if isinstance(v, (datetime.date, datetime.datetime)):
		v = text_type(v)
	elif isinstance(v, datetime.timedelta):
		v = ":".join(text_type(v).split(":")[:2])
	elif isinstance(v, integer_types):
		v = int(v)
	return v

def fmt_money(amount, precision=None, currency=None):
	"""
	Convert to string with commas for thousands, millions etc
	"""
	number_format = frappe.db.get_default("number_format") or "#,###.##"
	if precision is None:
		precision = cint(frappe.db.get_default('currency_precision')) or None

	decimal_str, comma_str, number_format_precision = get_number_format_info(number_format)

	if precision is None:
		precision = number_format_precision

	# 40,000 -> 40,000.00
	# 40,000.00000 -> 40,000.00
	# 40,000.23000 -> 40,000.23

	if isinstance(amount, string_types):
		amount = flt(amount, precision)

	if decimal_str:
		decimals_after = str(round(amount % 1, precision))
		parts = decimals_after.split('.')
		parts = parts[1] if len(parts) > 1 else parts[0]
		decimals = parts
		if precision > 2:
			if len(decimals) < 3:
				if currency:
					fraction  = frappe.db.get_value("Currency", currency, "fraction_units", cache=True) or 100
					precision = len(cstr(fraction)) - 1
				else:
					precision = number_format_precision
			elif len(decimals) < precision:
				precision = len(decimals)

	amount = '%.*f' % (precision, round(flt(amount), precision))

	if amount.find('.') == -1:
		decimals = ''
	else:
		decimals = amount.split('.')[1]

	parts = []
	minus = ''
	if flt(amount) < 0:
		minus = '-'

	amount = cstr(abs(flt(amount))).split('.')[0]

	if len(amount) > 3:
		parts.append(amount[-3:])
		amount = amount[:-3]

		val = number_format=="#,##,###.##" and 2 or 3

		while len(amount) > val:
			parts.append(amount[-val:])
			amount = amount[:-val]

	parts.append(amount)

	parts.reverse()

	amount = comma_str.join(parts) + ((precision and decimal_str) and (decimal_str + decimals) or "")
	if amount != '0':
		amount = minus + amount

	if currency and frappe.defaults.get_global_default("hide_currency_symbol") != "Yes":
		symbol = frappe.db.get_value("Currency", currency, "symbol", cache=True) or currency
		amount = symbol + " " + amount

	return amount

number_format_info = {
	"#,###.##": (".", ",", 2),
	"#.###,##": (",", ".", 2),
	"# ###.##": (".", " ", 2),
	"# ###,##": (",", " ", 2),
	"#'###.##": (".", "'", 2),
	"#, ###.##": (".", ", ", 2),
	"#,##,###.##": (".", ",", 2),
	"#,###.###": (".", ",", 3),
	"#.###": ("", ".", 0),
	"#,###": ("", ",", 0)
}

def get_number_format_info(format):
	return number_format_info.get(format) or (".", ",", 2)

#
# convert currency to words
#
def money_in_words(number, main_currency = None, fraction_currency=None):
	"""
	Returns string in words with currency and fraction currency.
	"""
	from frappe.utils import get_defaults
	_ = frappe._

	try:
		# note: `flt` returns 0 for invalid input and we don't want that
		number = float(number)
	except ValueError:
		return ""

	number = flt(number)
	if number < 0:
		return ""

	d = get_defaults()
	if not main_currency:
		main_currency = d.get('currency', 'INR')
	if not fraction_currency:
		fraction_currency = frappe.db.get_value("Currency", main_currency, "fraction", cache=True) or _("Cent")

	number_format = frappe.db.get_value("Currency", main_currency, "number_format", cache=True) or \
		frappe.db.get_default("number_format") or "#,###.##"

	fraction_length = get_number_format_info(number_format)[2]

	n = "%.{0}f".format(fraction_length) % number

	numbers = n.split('.')
	main, fraction =  numbers if len(numbers) > 1 else [n, '00']

	if len(fraction) < fraction_length:
		zeros = '0' * (fraction_length - len(fraction))
		fraction += zeros

	in_million = True
	if number_format == "#,##,###.##": in_million = False

	# 0.00
	if main == '0' and fraction in ['00', '000']:
		out = "{0} {1}".format(main_currency, _('Zero'))
	# 0.XX
	elif main == '0':
		out = _(in_words(fraction, in_million).title()) + ' ' + fraction_currency
	else:
		out = main_currency + ' ' + _(in_words(main, in_million).title())
		if cint(fraction):
			out = out + ' ' + _('and') + ' ' + _(in_words(fraction, in_million).title()) + ' ' + fraction_currency

	return out + ' ' + _('only.')

#
# convert number to words
#
def in_words(integer, in_million=True):
	"""
	Returns string in words for the given integer.
	"""
	from num2words import num2words

	locale = 'en_IN' if not in_million else frappe.local.lang
	integer = int(integer)
	try:
		ret = num2words(integer, lang=locale)
	except NotImplementedError:
		ret = num2words(integer, lang='en')
	except OverflowError:
		ret = num2words(integer, lang='en')
	return ret.replace('-', ' ')

def is_html(text):
	if not isinstance(text, str):
		return False
	return re.search('<[^>]+>', text)

def is_image(filepath):
	from mimetypes import guess_type

	# filepath can be https://example.com/bed.jpg?v=129
	filepath = (filepath or "").split('?')[0]
	return (guess_type(filepath)[0] or "").startswith("image/")

def get_thumbnail_base64_for_image(src):
	from os.path import exists as file_exists
	from PIL import Image
	from frappe.core.doctype.file.file import get_local_image
	from frappe import safe_decode, cache

	if not src:
		frappe.throw('Invalid source for image: {0}'.format(src))

	if not src.startswith('/files') or '..' in src:
		return

	if src.endswith('.svg'):
		return

	def _get_base64():
		file_path = frappe.get_site_path("public", src.lstrip("/"))
		if not file_exists(file_path):
			return

		try:
			image, unused_filename, extn = get_local_image(src)
		except IOError:
			return

		original_size = image.size
		size = 50, 50
		image.thumbnail(size, Image.ANTIALIAS)

		base64_string = image_to_base64(image, extn)
		return {
			'base64': 'data:image/{0};base64,{1}'.format(extn, safe_decode(base64_string)),
			'width': original_size[0],
			'height': original_size[1]
		}

	return cache().hget('thumbnail_base64', src, generator=_get_base64)

def image_to_base64(image, extn):
	import base64
	from io import BytesIO

	buffered = BytesIO()
	if extn.lower() in ('jpg', 'jpe'):
		extn = 'JPEG'
	image.save(buffered, extn)
	img_str = base64.b64encode(buffered.getvalue())
	return img_str


# from Jinja2 code
_striptags_re = re.compile(r'(<!--.*?-->|<[^>]*>)')
def strip_html(text):
	"""removes anything enclosed in and including <>"""
	return _striptags_re.sub("", text)

def escape_html(text):
	if not isinstance(text, string_types):
		return text

	html_escape_table = {
		"&": "&amp;",
		'"': "&quot;",
		"'": "&apos;",
		">": "&gt;",
		"<": "&lt;",
	}

	return "".join(html_escape_table.get(c,c) for c in text)

def pretty_date(iso_datetime):
	"""
		Takes an ISO time and returns a string representing how
		long ago the date represents.
		Ported from PrettyDate by John Resig
	"""
	from frappe import _
	if not iso_datetime: return ''
	import math

	if isinstance(iso_datetime, string_types):
		iso_datetime = datetime.datetime.strptime(iso_datetime, DATETIME_FORMAT)
	now_dt = datetime.datetime.strptime(now(), DATETIME_FORMAT)
	dt_diff = now_dt - iso_datetime

	# available only in python 2.7+
	# dt_diff_seconds = dt_diff.total_seconds()

	dt_diff_seconds = dt_diff.days * 86400.0 + dt_diff.seconds

	dt_diff_days = math.floor(dt_diff_seconds / 86400.0)

	# differnt cases
	if dt_diff_seconds < 60.0:
		return _('just now')
	elif dt_diff_seconds < 120.0:
		return _('1 minute ago')
	elif dt_diff_seconds < 3600.0:
		return _('{0} minutes ago').format(cint(math.floor(dt_diff_seconds / 60.0)))
	elif dt_diff_seconds < 7200.0:
		return _('1 hour ago')
	elif dt_diff_seconds < 86400.0:
		return _('{0} hours ago').format(cint(math.floor(dt_diff_seconds / 3600.0)))
	elif dt_diff_days == 1.0:
		return _('Yesterday')
	elif dt_diff_days < 7.0:
		return _('{0} days ago').format(cint(dt_diff_days))
	elif dt_diff_days < 12:
		return _('1 week ago')
	elif dt_diff_days < 31.0:
		return _('{0} weeks ago').format(cint(math.ceil(dt_diff_days / 7.0)))
	elif dt_diff_days < 46:
		return _('1 month ago')
	elif dt_diff_days < 365.0:
		return _('{0} months ago').format(cint(math.ceil(dt_diff_days / 30.0)))
	elif dt_diff_days < 550.0:
		return _('1 year ago')
	else:
		return '{0} years ago'.format(cint(math.floor(dt_diff_days / 365.0)))

def comma_or(some_list, add_quotes=True):
	return comma_sep(some_list, frappe._("{0} or {1}"), add_quotes)

def comma_and(some_list ,add_quotes=True):
	return comma_sep(some_list, frappe._("{0} and {1}"), add_quotes)

def comma_sep(some_list, pattern, add_quotes=True):
	if isinstance(some_list, (list, tuple)):
		# list(some_list) is done to preserve the existing list
		some_list = [text_type(s) for s in list(some_list)]
		if not some_list:
			return ""
		elif len(some_list) == 1:
			return some_list[0]
		else:
			some_list = ["'%s'" % s for s in some_list] if add_quotes else ["%s" % s for s in some_list]
			return pattern.format(", ".join(frappe._(s) for s in some_list[:-1]), some_list[-1])
	else:
		return some_list

def new_line_sep(some_list):
	if isinstance(some_list, (list, tuple)):
		# list(some_list) is done to preserve the existing list
		some_list = [text_type(s) for s in list(some_list)]
		if not some_list:
			return ""
		elif len(some_list) == 1:
			return some_list[0]
		else:
			some_list = ["%s" % s for s in some_list]
			return format("\n ".join(some_list))
	else:
		return some_list


def filter_strip_join(some_list, sep):
	"""given a list, filter None values, strip spaces and join"""
	return (cstr(sep)).join((cstr(a).strip() for a in filter(None, some_list)))

def get_url(uri=None, full_address=False):
	"""get app url from request"""
	host_name = frappe.local.conf.host_name or frappe.local.conf.hostname

	if uri and (uri.startswith("http://") or uri.startswith("https://")):
		return uri

	if not host_name:
		request_host_name = get_host_name_from_request()

		if request_host_name:
			host_name = request_host_name

		elif frappe.local.site:
			protocol = 'http://'

			if frappe.local.conf.ssl_certificate:
				protocol = 'https://'

			elif frappe.local.conf.wildcard:
				domain = frappe.local.conf.wildcard.get('domain')
				if domain and frappe.local.site.endswith(domain) and frappe.local.conf.wildcard.get('ssl_certificate'):
					protocol = 'https://'

			host_name = protocol + frappe.local.site

		else:
			host_name = frappe.db.get_value("Website Settings", "Website Settings",
				"subdomain")

			if not host_name:
				host_name = "http://localhost"

	if host_name and not (host_name.startswith("http://") or host_name.startswith("https://")):
		host_name = "http://" + host_name

	if not uri and full_address:
		uri = frappe.get_request_header("REQUEST_URI", "")

	port = frappe.conf.http_port or frappe.conf.webserver_port

	if not (frappe.conf.restart_supervisor_on_update or frappe.conf.restart_systemd_on_update) and host_name and not url_contains_port(host_name) and port:
		host_name = host_name + ':' + str(port)

	url = urljoin(host_name, uri) if uri else host_name

	return url

def get_host_name_from_request():
	if hasattr(frappe.local, "request") and frappe.local.request and frappe.local.request.host:
		protocol = 'https://' if 'https' == frappe.get_request_header('X-Forwarded-Proto', "") else 'http://'
		return protocol + frappe.local.request.host

def url_contains_port(url):
	parts = url.split(':')
	return len(parts) > 2

def get_host_name():
	return get_url().rsplit("//", 1)[-1]

def get_link_to_form(doctype, name, label=None):
	if not label: label = name

	return """<a href="{0}">{1}</a>""".format(get_url_to_form(doctype, name), label)

def get_link_to_report(name, label=None, report_type=None, doctype=None, filters=None):
	if not label: label = name

	if filters:
		conditions = []
		for k,v in iteritems(filters):
			if isinstance(v, list):
				for value in v:
					conditions.append(str(k)+'='+'["'+str(value[0]+'"'+','+'"'+str(value[1])+'"]'))
			else:
				conditions.append(str(k)+"="+str(v))

		filters = "&".join(conditions)

		return """<a href='{0}'>{1}</a>""".format(get_url_to_report_with_filters(name, filters, report_type, doctype), label)
	else:
		return """<a href='{0}'>{1}</a>""".format(get_url_to_report(name, report_type, doctype), label)

def get_absolute_url(doctype, name):
	return "/app/{0}/{1}".format(quoted(slug(doctype)), quoted(name))

def get_url_to_form(doctype, name):
	return get_url(uri = "/app/{0}/{1}".format(quoted(slug(doctype)), quoted(name)))

def get_url_to_list(doctype):
	return get_url(uri = "/app/{0}".format(quoted(slug(doctype))))

def get_url_to_report(name, report_type = None, doctype = None):
	if report_type == "Report Builder":
		return get_url(uri = "/app/{0}/view/report/{1}".format(quoted(slug(doctype)), quoted(name)))
	else:
		return get_url(uri = "/app/query-report/{0}".format(quoted(name)))

def get_url_to_report_with_filters(name, filters, report_type = None, doctype = None):
	if report_type == "Report Builder":
		return get_url(uri = "/app/{0}/view/report?{1}".format(quoted(doctype), filters))
	else:
		return get_url(uri = "/app/query-report/{0}?{1}".format(quoted(name), filters))

operator_map = {
	# startswith
	"^": lambda a, b: (a or "").startswith(b),

	# in or not in a list
	"in": lambda a, b: operator.contains(b, a),
	"not in": lambda a, b: not operator.contains(b, a),

	# comparison operators
	"=": lambda a, b: operator.eq(a, b),
	"!=": lambda a, b: operator.ne(a, b),
	">": lambda a, b: operator.gt(a, b),
	"<": lambda a, b: operator.lt(a, b),
	">=": lambda a, b: operator.ge(a, b),
	"<=": lambda a, b: operator.le(a, b),
	"not None": lambda a, b: a and True or False,
	"None": lambda a, b: (not a) and True or False
}

def evaluate_filters(doc, filters):
	'''Returns true if doc matches filters'''
	if isinstance(filters, dict):
		for key, value in iteritems(filters):
			f = get_filter(None, {key:value})
			if not compare(doc.get(f.fieldname), f.operator, f.value, f.fieldtype):
				return False

	elif isinstance(filters, (list, tuple)):
		for d in filters:
			f = get_filter(None, d)
			if not compare(doc.get(f.fieldname), f.operator, f.value, f.fieldtype):
				return False

	return True


def compare(val1, condition, val2, fieldtype=None):
	ret = False
	if fieldtype:
		val2 = cast_fieldtype(fieldtype, val2)
	if condition in operator_map:
		ret = operator_map[condition](val1, val2)

	return ret

def get_filter(doctype, f, filters_config=None):
	"""Returns a _dict like

		{
			"doctype":
			"fieldname":
			"operator":
			"value":
			"fieldtype":
		}
	"""
	from frappe.model import default_fields, optional_fields

	if isinstance(f, dict):
		key, value = next(iter(f.items()))
		f = make_filter_tuple(doctype, key, value)

	if not isinstance(f, (list, tuple)):
		frappe.throw(frappe._("Filter must be a tuple or list (in a list)"))

	if len(f) == 3:
		f = (doctype, f[0], f[1], f[2])
	elif len(f) > 4:
		f = f[0:4]
	elif len(f) != 4:
		frappe.throw(frappe._("Filter must have 4 values (doctype, fieldname, operator, value): {0}").format(str(f)))

	f = frappe._dict(doctype=f[0], fieldname=f[1], operator=f[2], value=f[3])

	sanitize_column(f.fieldname)

	if not f.operator:
		# if operator is missing
		f.operator = "="

	valid_operators = ("=", "!=", ">", "<", ">=", "<=", "like", "not like", "in", "not in", "is",
		"between", "descendants of", "ancestors of", "not descendants of", "not ancestors of",
		"timespan", "previous", "next")

	if filters_config:
		additional_operators = []
		for key in filters_config:
			additional_operators.append(key.lower())
		valid_operators = tuple(set(valid_operators + tuple(additional_operators)))

	if f.operator.lower() not in valid_operators:
		frappe.throw(frappe._("Operator must be one of {0}").format(", ".join(valid_operators)))


	if f.doctype and (f.fieldname not in default_fields + optional_fields):
		# verify fieldname belongs to the doctype
		meta = frappe.get_meta(f.doctype)
		if not meta.has_field(f.fieldname):

			# try and match the doctype name from child tables
			for df in meta.get_table_fields():
				if frappe.get_meta(df.options).has_field(f.fieldname):
					f.doctype = df.options
					break

	try:
		df = frappe.get_meta(f.doctype).get_field(f.fieldname)
	except frappe.exceptions.DoesNotExistError:
		df = None

	f.fieldtype = df.fieldtype if df else None

	return f

def make_filter_tuple(doctype, key, value):
	'''return a filter tuple like [doctype, key, operator, value]'''
	if isinstance(value, (list, tuple)):
		return [doctype, key, value[0], value[1]]
	else:
		return [doctype, key, "=", value]

def make_filter_dict(filters):
	'''convert this [[doctype, key, operator, value], ..]
	to this { key: (operator, value), .. }
	'''
	_filter = frappe._dict()
	for f in filters:
		_filter[f[1]] = (f[2], f[3])

	return _filter

def sanitize_column(column_name):
	from frappe import _
	import sqlparse
	regex = re.compile("^.*[,'();].*")
	column_name = sqlparse.format(column_name, strip_comments=True, keyword_case="lower")
	blacklisted_keywords = ['select', 'create', 'insert', 'delete', 'drop', 'update', 'case', 'and', 'or']

	def _raise_exception():
		frappe.throw(_("Invalid field name {0}").format(column_name), frappe.DataError)

	if 'ifnull' in column_name:
		if regex.match(column_name):
			# to avoid and, or
			if any(' {0} '.format(keyword) in column_name.split() for keyword in blacklisted_keywords):
				_raise_exception()

			# to avoid select, delete, drop, update and case
			elif any(keyword in column_name.split() for keyword in blacklisted_keywords):
				_raise_exception()

	elif regex.match(column_name):
		_raise_exception()

def scrub_urls(html):
	html = expand_relative_urls(html)
	# encoding should be responsibility of the composer
	# html = quote_urls(html)
	return html

def expand_relative_urls(html):
	# expand relative urls
	url = get_url()
	if url.endswith("/"): url = url[:-1]

	def _expand_relative_urls(match):
		to_expand = list(match.groups())

		if not to_expand[2].startswith('mailto') and not to_expand[2].startswith('data:'):
			if not to_expand[2].startswith("/"):
				to_expand[2] = "/" + to_expand[2]
			to_expand.insert(2, url)

		if 'url' in to_expand[0] and to_expand[1].startswith('(') and to_expand[-1].endswith(')'):
			# background-image: url('/assets/...') - workaround for wkhtmltopdf print-media-type
			to_expand.append(' !important')

		return "".join(to_expand)

	html = re.sub('(href|src){1}([\s]*=[\s]*[\'"]?)((?!http)[^\'" >]+)([\'"]?)', _expand_relative_urls, html)

	# background-image: url('/assets/...')
	html = re.sub('(:[\s]?url)(\([\'"]?)((?!http)[^\'" >]+)([\'"]?\))', _expand_relative_urls, html)
	return html

def quoted(url):
	return cstr(quote(encode(url), safe=b"~@#$&()*!+=:;,.?/'"))

def quote_urls(html):
	def _quote_url(match):
		groups = list(match.groups())
		groups[2] = quoted(groups[2])
		return "".join(groups)
	return re.sub('(href|src){1}([\s]*=[\s]*[\'"]?)((?:http)[^\'">]+)([\'"]?)',
		_quote_url, html)

def unique(seq):
	"""use this instead of list(set()) to preserve order of the original list.
	Thanks to Stackoverflow: http://stackoverflow.com/questions/480214/how-do-you-remove-duplicates-from-a-list-in-python-whilst-preserving-order"""

	seen = set()
	seen_add = seen.add
	return [ x for x in seq if not (x in seen or seen_add(x)) ]

def strip(val, chars=None):
	# \ufeff is no-width-break, \u200b is no-width-space
	return (val or "").replace("\ufeff", "").replace("\u200b", "").strip(chars)

def to_markdown(html):
	from html2text import html2text
	from six.moves import html_parser as HTMLParser

	text = None
	try:
		text = html2text(html or '')
	except HTMLParser.HTMLParseError:
		pass

	return text

def md_to_html(markdown_text):
	from markdown2 import markdown as _markdown, MarkdownError

	extras = {
		'fenced-code-blocks': None,
		'tables': None,
		'header-ids': None,
		'toc': None,
		'highlightjs-lang': None,
		'html-classes': {
			'table': 'table table-bordered',
			'img': 'screenshot'
		}
	}

	html = None
	try:
		html = UnicodeWithAttrs(_markdown(markdown_text or '', extras=extras))
	except MarkdownError:
		pass

	return html

def markdown(markdown_text):
	return md_to_html(markdown_text)

def is_subset(list_a, list_b):
	'''Returns whether list_a is a subset of list_b'''
	return len(list(set(list_a) & set(list_b))) == len(list_a)

def generate_hash(*args, **kwargs):
	return frappe.generate_hash(*args, **kwargs)

def guess_date_format(date_string):
	DATE_FORMATS = [
		r"%d/%b/%y",
		r"%d-%m-%Y",
		r"%m-%d-%Y",
		r"%Y-%m-%d",
		r"%d-%m-%y",
		r"%m-%d-%y",
		r"%y-%m-%d",
		r"%y-%b-%d",
		r"%d/%m/%Y",
		r"%m/%d/%Y",
		r"%Y/%m/%d",
		r"%d/%m/%y",
		r"%m/%d/%y",
		r"%y/%m/%d",
		r"%d.%m.%Y",
		r"%m.%d.%Y",
		r"%Y.%m.%d",
		r"%d.%m.%y",
		r"%m.%d.%y",
		r"%y.%m.%d",
		r"%d %b %Y",
		r"%d %B %Y",
	]

	TIME_FORMATS = [
		r"%H:%M:%S.%f",
		r"%H:%M:%S",
		r"%H:%M",
		r"%I:%M:%S.%f %p",
		r"%I:%M:%S %p",
		r"%I:%M %p",
	]

	def _get_date_format(date_str):
		for f in DATE_FORMATS:
			try:
				# if date is parsed without any exception
				# capture the date format
				datetime.datetime.strptime(date_str, f)
				return f
			except ValueError:
				pass

	def _get_time_format(time_str):
		for f in TIME_FORMATS:
			try:
				# if time is parsed without any exception
				# capture the time format
				datetime.datetime.strptime(time_str, f)
				return f
			except ValueError:
				pass

	date_format = None
	time_format = None
	date_string = date_string.strip()

	# check if date format can be guessed
	date_format = _get_date_format(date_string)
	if date_format:
		return date_format

	# date_string doesnt look like date, it can have a time part too
	# split the date string into date and time parts
	if " " in date_string:
		date_str, time_str = date_string.split(" ", 1)

		date_format = _get_date_format(date_str) or ''
		time_format = _get_time_format(time_str) or ''

		if date_format and time_format:
			return (date_format + ' ' + time_format).strip()

def validate_json_string(string):
	try:
		json.loads(string)
	except (TypeError, ValueError):
		raise frappe.ValidationError

def get_user_info_for_avatar(user_id):
	user_info = {
		"email": user_id,
		"image": "",
		"name": user_id
	}
	try:
		user_info["email"] = frappe.get_cached_value("User", user_id, "email")
		user_info["name"] = frappe.get_cached_value("User", user_id, "fullname")
		user_info["image"] = frappe.get_cached_value("User", user_id, "user_image")
	except Exception:
		frappe.local.message_log = []
	return user_info


class UnicodeWithAttrs(text_type):
	def __init__(self, text):
		self.toc_html = text.toc_html
		self.metadata = text.metadata