import template
import plugin
import string
import os

import locale
from datetime import datetime,timedelta,date
import jinja2
import json

class TabularCalendarPlugin:
    def __init__(self):
        calpath = os.path.join(template.path, 'calendar.json')

        with open(calpath, 'r') as calfile:
            events = json.load(calfile)
        for event in events:
            event['start'] = datetime.strptime(event['start'], '%Y-%m-%dT%H:%M:%S')
            event['end'] = datetime.strptime(event['end'], '%Y-%m-%dT%H:%M:%S')
            event['multiday'] = (event['end'] - event['start']) > timedelta(days=1)
        events = sorted(events, key=lambda x:x['start'])

        i = 0
        for event in events:
            event['id'] = i
            i += 1

        first = events[0]['start']
        last = events[-1]['end']

        calendar_start = first - timedelta(days=first.weekday())
        if calendar_start.month != first.month:
            calendar_start = date(first.year, first.month, 1)
        else:
            calendar_start = date(calendar_start.year,
                                  calendar_start.month,
                                  calendar_start.day)
        calendar_end = last + timedelta(days=6 - last.weekday())
        if calendar_end.month != last.month:
            calendar_end = date(last.year,last.month,last.day)
            while True:
                next_end = calendar_end + timedelta(days=1)
                if next_end.month != calendar_end.month:
                    break
                calendar_end = next_end
        else:
            calendar_end = date(calendar_end.year,
                                calendar_end.month,
                                calendar_end.day)

        months = []
        cur_day = calendar_start
        active_month = None
        active_week = None
        while cur_day <= calendar_end:
            cur_month = cur_day.month
            cur_week = cur_day.isocalendar()[1]

            if cur_month != active_month:
                months.append({
                    'year': cur_day.year,
                    'month': cur_day.month,
                    'date': date(cur_day.year, cur_day.month, 1),
                    'weeks': [[]]
                })
                active_week = cur_week
                active_month = cur_month
            if cur_week != active_week:
                months[-1]['weeks'].append([])
                active_week = cur_week

            week_list = months[-1]['weeks'][-1]
            week_list.append({
                    'year': cur_day.year,
                    'month': cur_day.month,
                    'day': cur_day.day,
                    'weekday': cur_day.weekday(),
                    'events': []
            })
            event_list = week_list[-1]['events']
            day_start = datetime(cur_day.year, cur_day.month, cur_day.day)
            day_end = day_start + timedelta(days=1)

            for event in events:
                if event['start'] >= day_end \
                   or event['end'] <= day_start:
                    continue
                event_list.append(event)

            cur_day += timedelta(days=1)

        self.months = months
        self.events = events
        template_loader = jinja2.FileSystemLoader(searchpath=os.path.join(template.path))
        self.template_env = jinja2.Environment(loader=template_loader)
        locale.setlocale(locale.LC_ALL, 'de_DE.UTF-8')

    def _get_calendar(self):
        return self.template_env.get_template('tabcalendar.j2').render({
            'months': self.months,
            'events': self.events,
        }).encode('utf-8')

    def process_content(self, page_content):
        return_value = {}
        for filename, content in page_content.iteritems():
            t = string.Template(content)
            return_value[filename] = t.safe_substitute(
                tabcalendar = self._get_calendar(),
            )
        return return_value

plugin.plugin_manager.register(TabularCalendarPlugin())