# copyright 2003-2010 LOGILAB S.A. (Paris, FRANCE), all rights reserved.

# contact http://www.logilab.fr/ -- mailto:contact@logilab.fr

#

# This file is part of CubicWeb.

#

# CubicWeb is free software: you can redistribute it and/or modify it under the

# terms of the GNU Lesser General Public License as published by the Free

# Software Foundation, either version 2.1 of the License, or (at your option)

# any later version.

#

# CubicWeb is distributed in the hope that it will be useful, but WITHOUT

# ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS

# FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License for more

# details.

#

# You should have received a copy of the GNU Lesser General Public License along

# with CubicWeb.  If not, see <http://www.gnu.org/licenses/>.

"""html calendar views"""

from datetime import date, time, timedelta

from logilab.mtconverter import xml_escape

from logilab.common.date import (ONEDAY, ONEWEEK, days_in_month, previous_month,

                                 next_month, first_day, last_day, date_range)

from cubicweb.interfaces import ICalendarViews

from cubicweb.selectors import implements, adaptable

from cubicweb.view import EntityView, EntityAdapter, implements_adapter_compat

class ICalendarViewsAdapter(EntityAdapter):

    """calendar views interface"""

    __regid__ = 'ICalendarViews'

    __select__ = implements(ICalendarViews, warn=False) # XXX for bw compat, should be abstract

    @implements_adapter_compat('ICalendarViews')

    def matching_dates(self, begin, end):

        """

        :param begin: day considered as begin of the range (`DateTime`)

        :param end: day considered as end of the range (`DateTime`)

        :return:

          a list of dates (`DateTime`) in the range [`begin`, `end`] on which

          this entity apply

        """

        raise NotImplementedError

# used by i18n tools

WEEKDAYS = [_("monday"), _("tuesday"), _("wednesday"), _("thursday"),

            _("friday"), _("saturday"), _("sunday")]

MONTHNAMES = [ _('january'), _('february'), _('march'), _('april'), _('may'),

               _('june'), _('july'), _('august'), _('september'), _('october'),

               _('november'), _('december')

               ]

class _CalendarView(EntityView):

    """base calendar view containing helpful methods to build calendar views"""

    __select__ = adaptable('ICalendarViews')

    paginable = False

    # Navigation building methods / views ####################################

    PREV = u'<a href="%s">&lt;&lt;</a>&#160;&#160;<a href="%s">&lt;</a>'

    NEXT = u'<a href="%s">&gt;</a>&#160;&#160;<a href="%s">&gt;&gt;</a>'

    NAV_HEADER = u"""<table class="calendarPageHeader">

<tr><td class="prev">%s</td><td class="next">%s</td></tr>

</table>

""" % (PREV, NEXT)

    def nav_header(self, date, smallshift=3, bigshift=9):

        """prints shortcut links to go to previous/next steps (month|week)"""

        prev1 = previous_month(date, smallshift)

        next1 = next_month(date, smallshift)

        prev2 = previous_month(date, bigshift)

        next2 = next_month(date, bigshift)

        rql = self.cw_rset.printable_rql()

        return self.NAV_HEADER % (

            xml_escape(self._cw.build_url(rql=rql, vid=self.__regid__, year=prev2.year,

                                          month=prev2.month)),

            xml_escape(self._cw.build_url(rql=rql, vid=self.__regid__, year=prev1.year,

                                          month=prev1.month)),

            xml_escape(self._cw.build_url(rql=rql, vid=self.__regid__, year=next1.year,

                                          month=next1.month)),

            xml_escape(self._cw.build_url(rql=rql, vid=self.__regid__, year=next2.year,

                                          month=next2.month)))

    # Calendar building methods ##############################################

    def build_calendars(self, schedule, begin, end):

        """build several HTML calendars at once, one for each month

        between begin and end

        """

        return [self.build_calendar(schedule, date)

                for date in date_range(begin, end, incmonth=1)]

    def build_calendar(self, schedule, first_day):

        """method responsible for building *one* HTML calendar"""

        # FIXME  iterates between [first_day-first_day.day_of_week ;

        #                          last_day+6-last_day.day_of_week]

        umonth = self._cw.format_date(first_day, '%B %Y') # localized month name

        rows = []

        current_row = [NO_CELL] * first_day.weekday()

        for daynum in xrange(0, days_in_month(first_day)):

            # build cell day

            day = first_day + timedelta(daynum)

            events = schedule.get(day)

            if events:

                events = [u'\n'.join(event) for event in events.values()]

                current_row.append(CELL % (daynum+1, '\n'.join(events)))

            else:

                current_row.append(EMPTY_CELL % (daynum+1))

            # store & reset current row on Sundays

            if day.weekday() == 6:

                rows.append(u'<tr>%s%s</tr>' % (WEEKNUM_CELL % day.isocalendar()[1], ''.join(current_row)))

                current_row = []

        current_row.extend([NO_CELL] * (6-day.weekday()))

        rql = self.cw_rset.printable_rql()

        if day.weekday() != 6:

            rows.append(u'<tr>%s%s</tr>' % (WEEKNUM_CELL % day.isocalendar()[1], ''.join(current_row)))

        url = self._cw.build_url(rql=rql, vid='calendarmonth',

                                 year=first_day.year, month=first_day.month)

        monthlink = u'<a href="%s">%s</a>' % (xml_escape(url), umonth)

        return CALENDAR(self._cw) % (monthlink, '\n'.join(rows))

    def _mk_schedule(self, begin, end, itemvid='calendaritem'):

        """private method that gathers information from resultset

        and builds calendars according to it

        :param begin: begin of date range

        :param end: end of date rangs

        :param itemvid: which view to call to render elements in cells

        returns { day1 : { hour : [views] },

                  day2 : { hour : [views] } ... }

        """

        # put this here since all sub views are calling this method

        self._cw.add_css('cubicweb.calendar.css')

        schedule = {}

        for row in xrange(len(self.cw_rset.rows)):

            entity = self.cw_rset.get_entity(row, 0)

            infos = u'<div class="event">'

            infos += self._cw.view(itemvid, self.cw_rset, row=row)

            infos += u'</div>'

            for date_ in entity.cw_adapt_to('ICalendarViews').matching_dates(begin, end):

                day = date(date_.year, date_.month, date_.day)

                try:

                    dt = time(date_.hour, date_.minute, date_.second)

                except AttributeError:

                    # date instance

                    dt = time(0, 0, 0)

                schedule.setdefault(day, {})

                schedule[day].setdefault(dt, []).append(infos)

        return schedule

    @staticmethod

    def get_date_range(day, shift=4):

        """returns a couple (begin, end)

        <begin> is the first day of current_month - shift

        <end> is the last day of current_month + (shift+1)

        """

        begin = first_day(previous_month(day, shift))

        end = last_day(next_month(day, shift))

        return begin, end

    def _build_ampm_cells(self, events):

        """create a view without any hourly details.

        :param events: dictionnary with all events classified by hours

        """

        # split events according am/pm

        am_events = [event for e_time, e_list in events.iteritems()

                     if 0 <= e_time.hour < 12

                     for event in e_list]

        pm_events = [event for e_time, e_list in events.iteritems()

                     if 12 <= e_time.hour < 24

                     for event in e_list]

        # format each am/pm cell

        if am_events:

            am_content = AMPM_CONTENT % ("amCell", "am", '\n'.join(am_events))

        else:

            am_content = AMPM_EMPTY % ("amCell", "am")

        if pm_events:

            pm_content = AMPM_CONTENT % ("pmCell", "pm", '\n'.join(pm_events))

        else:

            pm_content = AMPM_EMPTY % ("pmCell", "pm")

        return am_content, pm_content

class YearCalendarView(_CalendarView):

    __regid__ = 'calendaryear'

    title = _('calendar (year)')

    def call(self, year=None, month=None):

        """this view renders a 3x3 calendars' table"""

        year = year or int(self._cw.form.get('year', date.today().year))

        month = month or int(self._cw.form.get('month', date.today().month))

        center_date = date(year, month, 1)

        begin, end = self.get_date_range(day=center_date)

        schedule = self._mk_schedule(begin, end)

        self.w(self.nav_header(center_date))

        calendars = tuple(self.build_calendars(schedule, begin, end))

        self.w(SMALL_CALENDARS_PAGE % calendars)

class SemesterCalendarView(_CalendarView):

    """this view renders three semesters as three rows of six columns,

    one column per month

    """

    __regid__ = 'calendarsemester'

    title = _('calendar (semester)')

    def call(self, year=None, month=None):

        year = year or int(self._cw.form.get('year', date.today().year))

        month = month or int(self._cw.form.get('month', date.today().month))

        begin = previous_month(date(year, month, 1), 2)

        end = next_month(date(year, month, 1), 3)

        schedule = self._mk_schedule(begin, end)

        self.w(self.nav_header(date(year, month, 1), 1, 6))

        self.w(u'<table class="semesterCalendar">')

        self.build_calendars(schedule, begin, end)

        self.w(u'</table>')

        self.w(self.nav_header(date(year, month, 1), 1, 6))

    def build_calendars(self, schedule, begin, end):

        self.w(u'<tr>')

        rql = self.cw_rset.printable_rql()

        for cur_month in date_range(begin, end, incmonth=1):

            umonth = u'%s %s' % (self._cw.format_date(cur_month, '%B'), cur_month.year)

            url = self._cw.build_url(rql=rql, vid=self.__regid__,

                                     year=cur_month.year, month=cur_month.month)

            self.w(u'<th colspan="2"><a href="%s">%s</a></th>' % (xml_escape(url),

                                                                  umonth))

        self.w(u'</tr>')

        _ = self._cw._

        for day_num in xrange(31):

            self.w(u'<tr>')

            for cur_month in date_range(begin, end, incmonth=1):

                if day_num >= days_in_month(cur_month):

                    self.w(u'%s%s' % (NO_CELL, NO_CELL))

                else:

                    day = date(cur_month.year, cur_month.month, day_num+1)

                    events = schedule.get(day)

                    self.w(u'<td>%s&#160;%s</td>\n' % (_(WEEKDAYS[day.weekday()])[0].upper(), day_num+1))

                    self.format_day_events(day, events)

            self.w(u'</tr>')

    def format_day_events(self, day, events):

        if events:

            events = ['\n'.join(event) for event in events.values()]

            self.w(WEEK_CELL % '\n'.join(events))

        else:

            self.w(WEEK_EMPTY_CELL)

class MonthCalendarView(_CalendarView):

    """this view renders a 3x1 calendars' table"""

    __regid__ = 'calendarmonth'

    title = _('calendar (month)')

    def call(self, year=None, month=None):

        year = year or int(self._cw.form.get('year', date.today().year))

        month = month or int(self._cw.form.get('month', date.today().month))

        center_date = date(year, month, 1)

        begin, end = self.get_date_range(day=center_date, shift=1)

        schedule = self._mk_schedule(begin, end)

        calendars = self.build_calendars(schedule, begin, end)

        self.w(self.nav_header(center_date, 1, 3))

        self.w(BIG_CALENDARS_PAGE % tuple(calendars))

        self.w(self.nav_header(center_date, 1, 3))

class WeekCalendarView(_CalendarView):

    """this view renders a calendar for week events"""

    __regid__ = 'calendarweek'

    title = _('calendar (week)')

    def call(self, year=None, week=None):

        year = year or int(self._cw.form.get('year', date.today().year))

        week = week or int(self._cw.form.get('week', date.today().isocalendar()[1]))

        day0 = date(year, 1, 1)

        first_day_of_week = day0 - day0.weekday()*ONEDAY + ONEWEEK

        begin, end = first_day_of_week- ONEWEEK, first_day_of_week + 2*ONEWEEK

        schedule = self._mk_schedule(begin, end, itemvid='calendarlargeitem')

        self.w(self.nav_header(first_day_of_week))

        self.w(u'<table class="weekCalendar">')

        _weeks = [(first_day_of_week-ONEWEEK, first_day_of_week-ONEDAY),

                  (first_day_of_week, first_day_of_week+6*ONEDAY),

                  (first_day_of_week+ONEWEEK, first_day_of_week+13*ONEDAY)]

        self.build_calendar(schedule, _weeks)

        self.w(u'</table>')

        self.w(self.nav_header(first_day_of_week))

    def build_calendar(self, schedule, weeks):

        rql = self.cw_rset.printable_rql()

        _ = self._cw._

        for monday, sunday in weeks:

            umonth = self._cw.format_date(monday, '%B %Y')

            url = self._cw.build_url(rql=rql, vid='calendarmonth',

                                     year=monday.year, month=monday.month)

            monthlink = '<a href="%s">%s</a>' % (xml_escape(url), umonth)

            self.w(u'<tr><th colspan="3">%s %s (%s)</th></tr>' \

                  % (_('week'), monday.isocalendar()[1], monthlink))

            for day in date_range(monday, sunday+ONEDAY):

                self.w(u'<tr>')

                self.w(u'<td>%s</td>' % _(WEEKDAYS[day.weekday()]))

                self.w(u'<td>%s</td>' % (day.strftime('%Y-%m-%d')))

                events = schedule.get(day)

                if events:

                    events = ['\n'.join(event) for event in events.values()]

                    self.w(WEEK_CELL % '\n'.join(events))

                else:

                    self.w(WEEK_EMPTY_CELL)

                self.w(u'</tr>')

    def nav_header(self, date, smallshift=1, bigshift=3):

        """prints shortcut links to go to previous/next steps (month|week)"""

        prev1 = date - ONEWEEK * smallshift

        prev2 = date - ONEWEEK * bigshift

        next1 = date + ONEWEEK * smallshift

        next2 = date + ONEWEEK * bigshift

        rql = self.cw_rset.printable_rql()

        return self.NAV_HEADER % (

            xml_escape(self._cw.build_url(rql=rql, vid=self.__regid__, year=prev2.year, week=prev2.isocalendar()[1])),

            xml_escape(self._cw.build_url(rql=rql, vid=self.__regid__, year=prev1.year, week=prev1.isocalendar()[1])),

            xml_escape(self._cw.build_url(rql=rql, vid=self.__regid__, year=next1.year, week=next1.isocalendar()[1])),

            xml_escape(self._cw.build_url(rql=rql, vid=self.__regid__, year=next2.year, week=next2.isocalendar()[1])))

class AMPMYearCalendarView(YearCalendarView):

    __regid__ = 'ampmcalendaryear'

    title = _('am/pm calendar (year)')

    def build_calendar(self, schedule, first_day):

        """method responsible for building *one* HTML calendar"""

        umonth = self._cw.format_date(first_day, '%B %Y') # localized month name