moved datehelper in place

lms/lib/datehelper/README.md

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+datehelper
+==========
+
+This Python module contains some useful date-related methods inspired by rails.

lms/lib/datehelper/__init__.py

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+from time_ago_in_words import *

lms/lib/datehelper/time_ago_in_words.py

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+from datetime import datetime, timedelta
+from dateutil.tz import tzlocal
+import calendar
+
+# only used for testing
+def _timedelta(**kwargs):
+    kwargs['days'] = kwargs.get('days', 0)
+    if kwargs.get('years', False):
+        # not really a good solution since ignoring leap years
+        # but this is only for test anyways
+        kwargs['days'] += kwargs['years'] * 365
+        del kwargs['years']
+    if kwargs.get('months', False):
+        kwargs['days'] += kwargs['months'] * 30
+        del kwargs['months']
+    return timedelta(**kwargs)
+
+def time_ago_in_words(from_time, include_seconds=False):
+    return distance_of_time_in_words(from_time, datetime.now(tzlocal()), include_seconds=False)
+
+distance_of_time_in_words_to_now = time_ago_in_words
+
+def _time_in_words(before_text, unit):
+    if before_text:
+        before_text += ' '
+    def time_in_words_generator(count):
+        if count <= 1:
+            if before_text == 'less than ':
+                if unit == 'hour':
+                    count = 'an'
+                else:
+                    count = 'a'
+            return '{0}{1} {2}'.format(before_text, count, unit)
+        else:
+            return '{0}{1} {2}s'.format(before_text, count, unit)
+    return time_in_words_generator
+
+def distance_of_time_in_words(from_time, to_time=0, include_seconds=False, options = {}):
+    """Return a rough description of the time interval between from_time and to_time.
+       This is a direct translation from rails in ActionView::Helpers::DateHelper.
+       Reference:
+       http://api.rubyonrails.org/classes/ActionView/Helpers/DateHelper.html#method-i-distance_of_time_in_words
+
+    >>> from_time = datetime.now(tzlocal())
+    >>> distance_of_time_in_words(from_time, from_time + _timedelta(minutes=50))
+    'about 1 hour'
+    >>> distance_of_time_in_words(from_time, from_time + _timedelta(seconds=15))
+    'less than a minute'
+    >>> distance_of_time_in_words(from_time, from_time + _timedelta(seconds=15), True)
+    'less than 20 seconds'
+    >>> distance_of_time_in_words(from_time, from_time + _timedelta(years=3))
+    'about 3 years'
+    >>> distance_of_time_in_words(from_time, from_time + _timedelta(hours=60))
+    '3 days'
+    >>> distance_of_time_in_words(from_time, from_time + _timedelta(seconds=45), True)
+    'less than a minute'
+    >>> distance_of_time_in_words(from_time, from_time + _timedelta(seconds=-45), True)
+    'less than a minute'
+    >>> distance_of_time_in_words(from_time, from_time + _timedelta(seconds=76))
+    '1 minute'
+    >>> distance_of_time_in_words(from_time, from_time + _timedelta(years=1, days=3))
+    'about 1 year'
+    >>> distance_of_time_in_words(from_time, from_time + _timedelta(years=3, months=6))
+    'over 3 years'
+    >>> distance_of_time_in_words(from_time, from_time + _timedelta(years=4, days=9, minutes=30, seconds=5))
+    'about 4 years'
+    >>> to_time = from_time + _timedelta(years=6, days=19)
+    >>> distance_of_time_in_words(from_time, to_time, True)
+    'about 6 years'
+    >>> distance_of_time_in_words(to_time, from_time, True)
+    'about 6 years'
+    >>> distance_of_time_in_words(from_time, from_time)
+    'less than a minute'
+    """
+
+    if isinstance(from_time, int):
+        from_time = datetime.fromtimestamp(time.time()+from_time)
+    if isinstance(to_time, int):
+        to_time = datetime.fromtimestamp(time.time()+to_time)
+
+    distance_in_minutes = int(round(abs((to_time - from_time).total_seconds()) / 60))
+    distance_in_seconds = int(round(abs((to_time - from_time).total_seconds())))
+    
+    less_than_x_minutes = _time_in_words('less than', 'minute')
+    less_than_x_seconds = _time_in_words('less than', 'second')
+    half_a_minute       = 'half a minute'
+    x_minutes           = _time_in_words('', 'minute')
+    about_x_hours       = _time_in_words('about', 'hour')
+    x_days              = _time_in_words('', 'day')
+    about_x_months      = _time_in_words('about', 'month')
+    x_months            = _time_in_words('', 'month')
+    about_x_years       = _time_in_words('about', 'year')
+    over_x_years        = _time_in_words('over', 'year')
+    almost_x_years      = _time_in_words('almost', 'year')
+
+    if 0 <= distance_in_minutes <= 1:
+        if not include_seconds:
+            if distance_in_minutes == 0:
+                return less_than_x_minutes(1)
+            else:
+                return x_minutes(distance_in_minutes)
+        else:
+            if 0 <= distance_in_seconds <= 4:
+                return less_than_x_seconds(5)
+            elif 5 <= distance_in_seconds <= 9:
+                return less_than_x_seconds(10)
+            elif 10 <= distance_in_seconds <= 19:
+                return less_than_x_seconds(20)
+            elif 20 <= distance_in_seconds <= 39:
+                return half_a_minute
+            elif 40 <= distance_in_seconds <= 59:
+                return less_than_x_minutes(1)
+            else:
+                return x_minutes(1)
+    elif 2 <= distance_in_minutes <= 44:
+        return x_minutes(distance_in_minutes)
+    elif 45 <= distance_in_minutes <= 89:
+        return about_x_hours(1)
+    elif 90 <= distance_in_minutes <= 1439:
+        return about_x_hours(int(round(float(distance_in_minutes) / 60.0)))
+    elif 1440 <= distance_in_minutes <= 2519:
+        return x_days(1)
+    elif 2520 <= distance_in_minutes <= 43199:
+        return x_days(int(round(float(distance_in_minutes) / 1440.0)))
+    elif 43200 <= distance_in_minutes <= 86399:
+        return about_x_months(1)
+    elif 86400 <= distance_in_minutes <= 525599:
+        return x_months(int(round(float(distance_in_minutes) / 43200.0)))
+    else:
+        fyear = from_time.year
+        if from_time.month >= 3:
+            fyear += 1
+        tyear = to_time.year
+        if to_time.month < 3:
+            tyear -= 1
+        leap_years = 0 if fyear > tyear else len([x for x in range(fyear, tyear + 1) if calendar.isleap(x)])
+        minute_offset_for_leap_year = leap_years * 1440
+        # Discount the leap year days when calculating year distance.
+        # e.g. if there are 20 leap year days between 2 dates having the same day
+        # and month then the based on 365 days calculation
+        # the distance in years will come out to over 80 years when in written
+        # english it would read better as about 80 years.
+        minutes_with_offset         = distance_in_minutes - minute_offset_for_leap_year
+        remainder                   = (minutes_with_offset % 525600)
+        distance_in_years           = (minutes_with_offset / 525600)
+        if remainder < 131400:
+            return about_x_years(distance_in_years)
+        elif remainder < 394200:
+            return over_x_years(distance_in_years)
+        else:
+            return almost_x_years(distance_in_years + 1)