"""Calendar printing functions



Note when comparing these calendars to the ones printed by cal(1): By

default, these calendars have Monday as the first day of the week, and

Sunday as the last (the European convention). Use setfirstweekday() to

set the first day of the week (0=Monday, 6=Sunday)."""



import sys

import datetime

import locale as _locale



__all__ = ["IllegalMonthError", "IllegalWeekdayError", "setfirstweekday",

           "firstweekday", "isleap", "leapdays", "weekday", "monthrange",

           "monthcalendar", "prmonth", "month", "prcal", "calendar",

           "timegm", "month_name", "month_abbr", "day_name", "day_abbr"]



# Exception raised for bad input (with string parameter for details)

error = ValueError



# Exceptions raised for bad input

class IllegalMonthError(ValueError):

    def __init__(self, month):

        self.month = month

    def __str__(self):

        return "bad month number %r; must be 1-12" % self.month





class IllegalWeekdayError(ValueError):

    def __init__(self, weekday):

        self.weekday = weekday

    def __str__(self):

        return "bad weekday number %r; must be 0 (Monday) to 6 (Sunday)" % self.weekday





# Constants for months referenced later

January = 1

February = 2



# Number of days per month (except for February in leap years)

mdays = [0, 31, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]



# This module used to have hard-coded lists of day and month names, as

# English strings.  The classes following emulate a read-only version of

# that, but supply localized names.  Note that the values are computed

# fresh on each call, in case the user changes locale between calls.



class _localized_month:



    _months = [datetime.date(2001, i+1, 1).strftime for i in range(12)]

    _months.insert(0, lambda x: "")



    def __init__(self, format):

        self.format = format



    def __getitem__(self, i):

        funcs = self._months[i]

        if isinstance(i, slice):

            return [f(self.format) for f in funcs]

        else:

            return funcs(self.format)



    def __len__(self):

        return 13





class _localized_day:



    # January 1, 2001, was a Monday.

    _days = [datetime.date(2001, 1, i+1).strftime for i in range(7)]



    def __init__(self, format):

        self.format = format



    def __getitem__(self, i):

        funcs = self._days[i]

        if isinstance(i, slice):

            return [f(self.format) for f in funcs]

        else:

            return funcs(self.format)



    def __len__(self):

        return 7





# Full and abbreviated names of weekdays

day_name = _localized_day('%A')

day_abbr = _localized_day('%a')



# Full and abbreviated names of months (1-based arrays!!!)

month_name = _localized_month('%B')

month_abbr = _localized_month('%b')



# Constants for weekdays

(MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY, SUNDAY) = range(7)





def isleap(year):

    """Return 1 for leap years, 0 for non-leap years."""

    return year % 4 == 0 and (year % 100 != 0 or year % 400 == 0)





def leapdays(y1, y2):

    """Return number of leap years in range [y1, y2).

       Assume y1 <= y2."""

    y1 -= 1

    y2 -= 1

    return (y2//4 - y1//4) - (y2//100 - y1//100) + (y2//400 - y1//400)





def weekday(year, month, day):

    """Return weekday (0-6 ~ Mon-Sun) for year (1970-...), month (1-12),

       day (1-31)."""

    return datetime.date(year, month, day).weekday()





def monthrange(year, month):

    """Return weekday (0-6 ~ Mon-Sun) and number of days (28-31) for

       year, month."""

    if not 1 <= month <= 12:

        raise IllegalMonthError(month)

    day1 = weekday(year, month, 1)

    ndays = mdays[month] + (month == February and isleap(year))

    return day1, ndays





class Calendar(object):

    """

    Base calendar class. This class doesn't do any formatting. It simply

    provides data to subclasses.

    """



    def __init__(self, firstweekday=0):

        self.firstweekday = firstweekday # 0 = Monday, 6 = Sunday



    def getfirstweekday(self):

        return self._firstweekday % 7



    def setfirstweekday(self, firstweekday):

        self._firstweekday = firstweekday



    firstweekday = property(getfirstweekday, setfirstweekday)



    def iterweekdays(self):

        """

        Return a iterator for one week of weekday numbers starting with the

        configured first one.

        """

        for i in range(self.firstweekday, self.firstweekday + 7):

            yield i%7



    def itermonthdates(self, year, month):

        """

        Return an iterator for one month. The iterator will yield datetime.date

        values and will always iterate through complete weeks, so it will yield

        dates outside the specified month.

        """

        date = datetime.date(year, month, 1)

        # Go back to the beginning of the week

        days = (date.weekday() - self.firstweekday) % 7

        date -= datetime.timedelta(days=days)

        oneday = datetime.timedelta(days=1)

        while True:

            yield date

            date += oneday

            if date.month != month and date.weekday() == self.firstweekday:

                break



    def itermonthdays2(self, year, month):

        """

        Like itermonthdates(), but will yield (day number, weekday number)

        tuples. For days outside the specified month the day number is 0.

        """

        for date in self.itermonthdates(year, month):

            if date.month != month:

                yield (0, date.weekday())

            else:

                yield (date.day, date.weekday())



    def itermonthdays(self, year, month):

        """

        Like itermonthdates(), but will yield day numbers. For days outside

        the specified month the day number is 0.

        """

        for date in self.itermonthdates(year, month):

            if date.month != month:

                yield 0

            else:

                yield date.day



    def monthdatescalendar(self, year, month):

        """

        Return a matrix (list of lists) representing a month's calendar.

        Each row represents a week; week entries are datetime.date values.

        """

        dates = list(self.itermonthdates(year, month))

        return [ dates[i:i+7] for i in range(0, len(dates), 7) ]



    def monthdays2calendar(self, year, month):

        """

        Return a matrix representing a month's calendar.

        Each row represents a week; week entries are

        (day number, weekday number) tuples. Day numbers outside this month

        are zero.

        """

        days = list(self.itermonthdays2(year, month))

        return [ days[i:i+7] for i in range(0, len(days), 7) ]



    def monthdayscalendar(self, year, month):

        """

        Return a matrix representing a month's calendar.

        Each row represents a week; days outside this month are zero.

        """

        days = list(self.itermonthdays(year, month))

        return [ days[i:i+7] for i in range(0, len(days), 7) ]



    def yeardatescalendar(self, year, width=3):

        """

        Return the data for the specified year ready for formatting. The return

        value is a list of month rows. Each month row contains upto width months.

        Each month contains between 4 and 6 weeks and each week contains 1-7

        days. Days are datetime.date objects.

        """

        months = [

            self.monthdatescalendar(year, i)

            for i in range(January, January+12)

        ]

        return [months[i:i+width] for i in range(0, len(months), width) ]



    def yeardays2calendar(self, year, width=3):

        """

        Return the data for the specified year ready for formatting (similar to

        yeardatescalendar()). Entries in the week lists are

        (day number, weekday number) tuples. Day numbers outside this month are

        zero.

        """

        months = [

            self.monthdays2calendar(year, i)

            for i in range(January, January+12)

        ]

        return [months[i:i+width] for i in range(0, len(months), width) ]



    def yeardayscalendar(self, year, width=3):

        """

        Return the data for the specified year ready for formatting (similar to

        yeardatescalendar()). Entries in the week lists are day numbers.

        Day numbers outside this month are zero.

        """

        months = [

            self.monthdayscalendar(year, i)

            for i in range(January, January+12)

        ]

        return [months[i:i+width] for i in range(0, len(months), width) ]





class TextCalendar(Calendar):

    """

    Subclass of Calendar that outputs a calendar as a simple plain text

    similar to the UNIX program cal.

    """



    def prweek(self, theweek, width):

        """

        Print a single week (no newline).

        """

        print self.formatweek(theweek, width),



    def formatday(self, day, weekday, width):

        """

        Returns a formatted day.

        """

        if day == 0:

            s = ''

        else:

            s = '%2i' % day             # right-align single-digit days

        return s.center(width)



    def formatweek(self, theweek, width):

        """

        Returns a single week in a string (no newline).

        """

        return ' '.join(self.formatday(d, wd, width) for (d, wd) in theweek)



    def formatweekday(self, day, width):

        """

        Returns a formatted week day name.

        """

        if width >= 9:

            names = day_name

        else:

            names = day_abbr

        return names[day][:width].center(width)



    def formatweekheader(self, width):

        """

        Return a header for a week.

        """

        return ' '.join(self.formatweekday(i, width) for i in self.iterweekdays())



    def formatmonthname(self, theyear, themonth, width, withyear=True):

        """

        Return a formatted month name.

        """

        s = month_name[themonth]

        if withyear:

            s = "%s %r" % (s, theyear)

        return s.center(width)



    def prmonth(self, theyear, themonth, w=0, l=0):

        """

        Print a month's calendar.

        """

        print self.formatmonth(theyear, themonth, w, l),



    def formatmonth(self, theyear, themonth, w=0, l=0):

        """

        Return a month's calendar string (multi-line).

        """

        w = max(2, w)

        l = max(1, l)

        s = self.formatmonthname(theyear, themonth, 7 * (w + 1) - 1)

        s = s.rstrip()

        s += '\n' * l

        s += self.formatweekheader(w).rstrip()

        s += '\n' * l

        for week in self.monthdays2calendar(theyear, themonth):

            s += self.formatweek(week, w).rstrip()

            s += '\n' * l

        return s



    def formatyear(self, theyear, w=2, l=1, c=6, m=3):

        """

        Returns a year's calendar as a multi-line string.

        """

        w = max(2, w)

        l = max(1, l)

        c = max(2, c)

        colwidth = (w + 1) * 7 - 1

        v = []

        a = v.append

        a(repr(theyear).center(colwidth*m+c*(m-1)).rstrip())

        a('\n'*l)

        header = self.formatweekheader(w)

        for (i, row) in enumerate(self.yeardays2calendar(theyear, m)):

            # months in this row

            months = range(m*i+1, min(m*(i+1)+1, 13))

            a('\n'*l)

            names = (self.formatmonthname(theyear, k, colwidth, False)

                     for k in months)

            a(formatstring(names, colwidth, c).rstrip())

            a('\n'*l)

            headers = (header for k in months)

            a(formatstring(headers, colwidth, c).rstrip())

            a('\n'*l)

            # max number of weeks for this row

            height = max(len(cal) for cal in row)

            for j in range(height):

                weeks = []

                for cal in row:

                    if j >= len(cal):

                        weeks.append('')

                    else:

                        weeks.append(self.formatweek(cal[j], w))

                a(formatstring(weeks, colwidth, c).rstrip())

                a('\n' * l)

        return ''.join(v)



    def pryear(self, theyear, w=0, l=0, c=6, m=3):

        """Print a year's calendar."""

        print self.formatyear(theyear, w, l, c, m)





class HTMLCalendar(Calendar):

    """

    This calendar returns complete HTML pages.

    """



    # CSS classes for the day <td>s

    cssclasses = ["mon", "tue", "wed", "thu", "fri", "sat", "sun"]



    def formatday(self, day, weekday):

        """

        Return a day as a table cell.

        """

        if day == 0:

            return '<td class="noday">&nbsp;</td>' # day outside month

        else:

            return '<td class="%s">%d</td>' % (self.cssclasses[weekday], day)



    def formatweek(self, theweek):

        """

        Return a complete week as a table row.

        """

        s = ''.join(self.formatday(d, wd) for (d, wd) in theweek)

        return '<tr>%s</tr>' % s



    def formatweekday(self, day):

        """

        Return a weekday name as a table header.

        """

        return '<th class="%s">%s</th>' % (self.cssclasses[day], day_abbr[day])



    def formatweekheader(self):

        """

        Return a header for a week as a table row.

        """

        s = ''.join(self.formatweekday(i) for i in self.iterweekdays())

        return '<tr>%s</tr>' % s



    def formatmonthname(self, theyear, themonth, withyear=True):

        """

        Return a month name as a table row.

        """

        if withyear:

            s = '%s %s' % (month_name[themonth], theyear)

        else:

            s = '%s' % month_name[themonth]

        return '<tr><th colspan="7" class="month">%s</th></tr>' % s



    def formatmonth(self, theyear, themonth, withyear=True):

        """

        Return a formatted month as a table.

        """

        v = []

        a = v.append

        a('<table border="0" cellpadding="0" cellspacing="0" class="month">')

        a('\n')

        a(self.formatmonthname(theyear, themonth, withyear=withyear))

        a('\n')

        a(self.formatweekheader())

        a('\n')

        for week in self.monthdays2calendar(theyear, themonth):

            a(self.formatweek(week))

            a('\n')

        a('</table>')

        a('\n')

        return ''.join(v)



    def formatyear(self, theyear, width=3):

        """

        Return a formatted year as a table of tables.

        """

        v = []

        a = v.append

        width = max(width, 1)

        a('<table border="0" cellpadding="0" cellspacing="0" class="year">')

        a('\n')

        a('<tr><th colspan="%d" class="year">%s</th></tr>' % (width, theyear))

        for i in range(January, January+12, width):

            # months in this row

            months = range(i, min(i+width, 13))

            a('<tr>')

            for m in months:

                a('<td>')

                a(self.formatmonth(theyear, m, withyear=False))

                a('</td>')

            a('</tr>')

        a('</table>')

        return ''.join(v)



    def formatyearpage(self, theyear, width=3, css='calendar.css', encoding=None):

        """

        Return a formatted year as a complete HTML page.

        """

        if encoding is None:

            encoding = sys.getdefaultencoding()

        v = []

        a = v.append

        a('<?xml version="1.0" encoding="%s"?>\n' % encoding)

        a('<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd">\n')

        a('<html>\n')

        a('<head>\n')

        a('<meta http-equiv="Content-Type" content="text/html; charset=%s" />\n' % encoding)

        if css is not None:

            a('<link rel="stylesheet" type="text/css" href="%s" />\n' % css)

        a('<title>Calendar for %d</title>\n' % theyear)

        a('</head>\n')

        a('<body>\n')

        a(self.formatyear(theyear, width))

        a('</body>\n')

        a('</html>\n')

        return ''.join(v).encode(encoding, "xmlcharrefreplace")





class TimeEncoding:

    def __init__(self, locale):

        self.locale = locale



    def __enter__(self):

        self.oldlocale = _locale.setlocale(_locale.LC_TIME, self.locale)

        return _locale.getlocale(_locale.LC_TIME)[1]



    def __exit__(self, *args):

        _locale.setlocale(_locale.LC_TIME, self.oldlocale)





class LocaleTextCalendar(TextCalendar):

    """

    This class can be passed a locale name in the constructor and will return

    month and weekday names in the specified locale. If this locale includes

    an encoding all strings containing month and weekday names will be returned

    as unicode.

    """



    def __init__(self, firstweekday=0, locale=None):

        TextCalendar.__init__(self, firstweekday)

        if locale is None:

            locale = _locale.getdefaultlocale()

        self.locale = locale



    def formatweekday(self, day, width):

        with TimeEncoding(self.locale) as encoding:

            if width >= 9:

                names = day_name

            else:

                names = day_abbr

            name = names[day]

            if encoding is not None:

                name = name.decode(encoding)

            return name[:width].center(width)



    def formatmonthname(self, theyear, themonth, width, withyear=True):

        with TimeEncoding(self.locale) as encoding:

            s = month_name[themonth]

            if encoding is not None:

                s = s.decode(encoding)

            if withyear:

                s = "%s %r" % (s, theyear)

            return s.center(width)





class LocaleHTMLCalendar(HTMLCalendar):

    """

    This class can be passed a locale name in the constructor and will return

    month and weekday names in the specified locale. If this locale includes

    an encoding all strings containing month and weekday names will be returned

    as unicode.

    """

    def __init__(self, firstweekday=0, locale=None):

        HTMLCalendar.__init__(self, firstweekday)

        if locale is None:

            locale = _locale.getdefaultlocale()

        self.locale = locale



    def formatweekday(self, day):

        with TimeEncoding(self.locale) as encoding:

            s = day_abbr[day]

            if encoding is not None:

                s = s.decode(encoding)

            return '<th class="%s">%s</th>' % (self.cssclasses[day], s)



    def formatmonthname(self, theyear, themonth, withyear=True):

        with TimeEncoding(self.locale) as encoding:

            s = month_name[themonth]

            if encoding is not None:

                s = s.decode(encoding)

            if withyear:

                s = '%s %s' % (s, theyear)

            return '<tr><th colspan="7" class="month">%s</th></tr>' % s





# Support for old module level interface

c = TextCalendar()



firstweekday = c.getfirstweekday



def setfirstweekday(firstweekday):

    if not MONDAY <= firstweekday <= SUNDAY:

        raise IllegalWeekdayError(firstweekday)

    c.firstweekday = firstweekday



monthcalendar = c.monthdayscalendar

prweek = c.prweek

week = c.formatweek

weekheader = c.formatweekheader

prmonth = c.prmonth

month = c.formatmonth

calendar = c.formatyear

prcal = c.pryear





# Spacing of month columns for multi-column year calendar

_colwidth = 7*3 - 1         # Amount printed by prweek()

_spacing = 6                # Number of spaces between columns





def format(cols, colwidth=_colwidth, spacing=_spacing):

    """Prints multi-column formatting for year calendars"""

    print formatstring(cols, colwidth, spacing)





def formatstring(cols, colwidth=_colwidth, spacing=_spacing):

    """Returns a string formatted from n strings, centered within n columns."""

    spacing *= ' '

    return spacing.join(c.center(colwidth) for c in cols)





EPOCH = 1970

_EPOCH_ORD = datetime.date(EPOCH, 1, 1).toordinal()





def timegm(tuple):

    """Unrelated but handy function to calculate Unix timestamp from GMT."""

    year, month, day, hour, minute, second = tuple[:6]

    days = datetime.date(year, month, 1).toordinal() - _EPOCH_ORD + day - 1

    hours = days*24 + hour

    minutes = hours*60 + minute

    seconds = minutes*60 + second

    return seconds





def main(args):

    import optparse

    parser = optparse.OptionParser(usage="usage: %prog [options] [year [month]]")

    parser.add_option(

        "-w", "--width",

        dest="width", type="int", default=2,

        help="width of date column (default 2, text only)"

    )

    parser.add_option(

        "-l", "--lines",

        dest="lines", type="int", default=1,

        help="number of lines for each week (default 1, text only)"

    )

    parser.add_option(

        "-s", "--spacing",

        dest="spacing", type="int", default=6,

        help="spacing between months (default 6, text only)"

    )

    parser.add_option(

        "-m", "--months",

        dest="months", type="int", default=3,

        help="months per row (default 3, text only)"

    )

    parser.add_option(

        "-c", "--css",

        dest="css", default="calendar.css",

        help="CSS to use for page (html only)"

    )

    parser.add_option(

        "-L", "--locale",

        dest="locale", default=None,

        help="locale to be used from month and weekday names"

    )

    parser.add_option(

        "-e", "--encoding",

        dest="encoding", default=None,

        help="Encoding to use for output"

    )

    parser.add_option(

        "-t", "--type",

        dest="type", default="text",

        choices=("text", "html"),

        help="output type (text or html)"

    )



    (options, args) = parser.parse_args(args)



    if options.locale and not options.encoding:

        parser.error("if --locale is specified --encoding is required")

        sys.exit(1)



    locale = options.locale, options.encoding



    if options.type == "html":

        if options.locale:

            cal = LocaleHTMLCalendar(locale=locale)

        else:

            cal = HTMLCalendar()

        encoding = options.encoding

        if encoding is None:

            encoding = sys.getdefaultencoding()

        optdict = dict(encoding=encoding, css=options.css)

        if len(args) == 1:

            print cal.formatyearpage(datetime.date.today().year, **optdict)

        elif len(args) == 2:

            print cal.formatyearpage(int(args[1]), **optdict)

        else:

            parser.error("incorrect number of arguments")

            sys.exit(1)

    else:

        if options.locale:

            cal = LocaleTextCalendar(locale=locale)

        else:

            cal = TextCalendar()

        optdict = dict(w=options.width, l=options.lines)

        if len(args) != 3:

            optdict["c"] = options.spacing

            optdict["m"] = options.months

        if len(args) == 1:

            result = cal.formatyear(datetime.date.today().year, **optdict)

        elif len(args) == 2:

            result = cal.formatyear(int(args[1]), **optdict)

        elif len(args) == 3:

            result = cal.formatmonth(int(args[1]), int(args[2]), **optdict)

        else:

            parser.error("incorrect number of arguments")

            sys.exit(1)

        if options.encoding:

            result = result.encode(options.encoding)

        print result





if __name__ == "__main__":

    main(sys.argv)

