"""
Widget for datetime split, with calendar for date, and drop-downs for times.
"""
from django import forms
from django.db import models
from django.template.loader import render_to_string
from django.forms.widgets import Select, MultiWidget, DateInput, TextInput, Widget, SelectDateWidget
from time import strftime
import re
from django.utils.safestring import mark_safe
__all__ = ('SelectTimeWidget', 'SplitSelectDateTimeWidget')
# Attempt to match many time formats:
# Example: "12:34:56 P.M." matches:
# ('12', '34', ':56', '56', 'P.M.', 'P', '.', 'M', '.')
# ('12', '34', ':56', '56', 'P.M.')
# Note that the colon ":" before seconds is optional, but only if seconds are omitted
time_pattern = r'(\d\d?):(\d\d)(:(\d\d))? *([aApP]\.?[mM]\.?)?$'
RE_TIME = re.compile(time_pattern)
# The following are just more readable ways to access re.matched groups:
HOURS = 0
MINUTES = 1
SECONDS = 3
MERIDIEM = 4
class SelectTimeWidget(Widget):
"""
A Widget that splits time input into <select> elements.
Allows form to show as 24hr: <hour>:<minute>:<second>, (default)
or as 12hr: <hour>:<minute>:<second> <am|pm>
Also allows user-defined increments for minutes/seconds
"""
template_name = ''
hour_field = '%s_hour'
minute_field = '%s_minute'
meridiem_field = '%s_meridiem'
twelve_hr = False # Default to 24hr.
def __init__(self, attrs=None, hour_step=None, minute_step=None, twelve_hr=False):
"""
hour_step, minute_step, second_step are optional step values for
for the range of values for the associated select element
twelve_hr: If True, forces the output to be in 12-hr format (rather than 24-hr)
"""
super(SelectTimeWidget, self).__init__(attrs)
if twelve_hr:
self.twelve_hr = True # Do 12hr (rather than 24hr)
self.meridiem_val = 'a.m.' # Default to Morning (A.M.)
if hour_step and twelve_hr:
self.hours = list(range(1,13,hour_step))
elif hour_step: # 24hr, with stepping.
self.hours = list(range(0,24,hour_step))
elif twelve_hr: # 12hr, no stepping
self.hours = list(range(1,13))
else: # 24hr, no stepping
self.hours = list(range(0,24))
if minute_step:
self.minutes = list(range(0,60,minute_step))
else:
self.minutes = list(range(0,60))
def render(self, name, value, attrs=None, renderer=None):
try: # try to get time values from a datetime.time object (value)
hour_val, minute_val = value.hour, value.minute
if self.twelve_hr:
if hour_val >= 12:
self.meridiem_val = 'p.m.'
else:
self.meridiem_val = 'a.m.'
except AttributeError:
hour_val = minute_val = 0
if isinstance(value, str):
match = RE_TIME.match(value)
if match:
time_groups = match.groups()
hour_val = int(time_groups[HOURS]) % 24 # force to range(0-24)
minute_val = int(time_groups[MINUTES])
# check to see if meridiem was passed in
if time_groups[MERIDIEM] is not None:
self.meridiem_val = time_groups[MERIDIEM]
else: # otherwise, set the meridiem based on the time
if self.twelve_hr:
if hour_val >= 12:
self.meridiem_val = 'p.m.'
else:
self.meridiem_val = 'a.m.'
else:
self.meridiem_val = None
# If we're doing a 12-hr clock, there will be a meridiem value, so make sure the
# hours get printed correctly
if self.twelve_hr and self.meridiem_val:
if self.meridiem_val.lower().startswith('p') and hour_val > 12 and hour_val < 24:
hour_val = hour_val % 12
elif hour_val == 0:
hour_val = 12
output = []
if 'id' in self.attrs:
id_ = self.attrs['id']
else:
id_ = 'id_%s' % name
# For times to get displayed correctly, the values MUST be converted to unicode
# When Select builds a list of options, it checks against Unicode values
hour_val = "%.2d" % hour_val
minute_val = "%.2d" % minute_val
hour_choices = [("%.2d"%i, "%.2d"%i) for i in self.hours]
local_attrs = self.build_attrs({'id': self.hour_field % id_})
select_html = Select(choices=hour_choices).render(self.hour_field % name, hour_val, local_attrs)
output.append(select_html)
minute_choices = [("%.2d"%i, "%.2d"%i) for i in self.minutes]
local_attrs['id'] = self.minute_field % id_
select_html = Select(choices=minute_choices).render(self.minute_field % name, minute_val, local_attrs)
output.append(select_html)
if self.twelve_hr:
# If we were given an initial value, make sure the correct meridiem gets selected.
if self.meridiem_val is not None and self.meridiem_val.startswith('p'):
meridiem_choices = [('p.m.','p.m.'), ('a.m.','a.m.')]
else:
meridiem_choices = [('a.m.','a.m.'), ('p.m.','p.m.')]
local_attrs['id'] = local_attrs['id'] = self.meridiem_field % id_
select_html = Select(choices=meridiem_choices).render(self.meridiem_field % name, self.meridiem_val, local_attrs)
output.append(select_html)
return mark_safe('\n'.join(output))
def id_for_label(self, id_):
return '%s_hour' % id_
id_for_label = classmethod(id_for_label)
def value_from_datadict(self, data, files, name):
# if there's not h:m:s data, assume zero:
h = data.get(self.hour_field % name, 0) # hour
m = data.get(self.minute_field % name, 0) # minute
meridiem = data.get(self.meridiem_field % name, None)
#NOTE: if meridiem is None, assume 24-hr
if meridiem is not None:
if meridiem.lower().startswith('p') and int(h) != 12:
h = (int(h)+12)%24
elif meridiem.lower().startswith('a') and int(h) == 12:
h = 0
if (int(h) == 0 or h) and m:
return '%s:%s' % (h, m)
return data.get(name, None)
class SplitSelectDateTimeWidget(MultiWidget):
"""
MultiWidget = A widget that is composed of multiple widgets.
This class combines SelectTimeWidget and SelectDateWidget so we have something
like SpliteDateTimeWidget (in django.forms.widgets), but with Select elements.
"""
template_name = ''
def __init__(self, attrs=None, hour_step=None, minute_step=None, twelve_hr=None, years=None):
""" pass all these parameters to their respective widget constructors..."""
widgets = (SelectDateWidget(attrs=attrs, years=years), SelectTimeWidget(attrs=attrs, hour_step=hour_step, minute_step=minute_step, twelve_hr=twelve_hr))
super(SplitSelectDateTimeWidget, self).__init__(widgets, attrs)
# See https://stackoverflow.com/questions/4324676/django-multiwidget-subclass-not-calling-decompress
def value_from_datadict(self, data, files, name):
if data.get(name, None) is None:
return [widget.value_from_datadict(data, files, name ) for widget in self.widgets]
return self.decompress(data.get(name, None))
def decompress(self, value):
if value:
return [value.date(), value.time().replace(microsecond=0)]
return [None, None]
def compress(self, data_list):
"""
Takes the values from the MultiWidget and passes them as a
list to this function. This function needs to compress the
list into a single object in order to be correctly rendered by the widget.
For instace, django.forms.widgets.SelectDateWidget.format_value(value)
expects a date object or a string, not a list.
This method was taken from helios/fields.py
"""
if data_list:
import datetime
if not (data_list[0] and data_list[1]):
return None
return datetime.datetime.combine(*data_list)
return None
def render(self, name, value, attrs=None, renderer=None):
value = self.compress(value)
rendered_widgets = list(widget.render(name, value, attrs=attrs, renderer=renderer) for widget in self.widgets)
return '<br/>'.join(rendered_widgets)