from datetime import datetime, timedelta
import time
import math

from django.views.decorators.cache import cache_control
from django.views.generic.base import TemplateView
from django.views.generic.detail import DetailView
from django.views.decorators.csrf import csrf_exempt
from django.views.generic.dates import _date_from_string

from django.core.paginator import Paginator

from jsonresponse import to_json

from emissions.models import Category, Emission, Episode, Diffusion, SoundFile, \
        Schedule, Nonstop, NewsItem, NewsCategory

from emissions.utils import whatsonair, period_program


class EmissionMixin:
    def get_emission_context(self, emission):
        context = {}

        # get all episodes, with an additional attribute to get the date of
        # their first diffusion
        context['episodes'] = \
                Episode.objects.select_related().filter(emission=emission
                    ).extra(select={
                        'first_diffusion': 'emissions_diffusion.datetime',
                        },
                        select_params=(False, True),
                        where=['''datetime = (SELECT MIN(datetime)
                                                FROM emissions_diffusion
                                               WHERE episode_id = emissions_episode.id)'''],
                        tables=['emissions_diffusion'],
                    ).order_by('-first_diffusion')

        # get all related soundfiles in a single query
        soundfiles = {}
        for soundfile in SoundFile.objects.select_related().filter(podcastable=True,
                fragment=False, episode__emission=emission):
            soundfiles[soundfile.episode_id] = soundfile

        # replace dynamic property by a static attribute, to avoid database
        # lookups
        for episode in context['episodes']:
            episode.main_sound = soundfiles.get(episode.id)

        return context



class EmissionDetailView(DetailView, EmissionMixin):
    model = Emission

    def get_context_data(self, **kwargs):
        context = super(EmissionDetailView, self).get_context_data(**kwargs)
        context['sectionName'] = "Emissions"
        context['schedules'] = Schedule.objects.select_related().filter(emission=self.object).order_by('datetime')
        context.update(self.get_emission_context(self.object))
        return context
emission = EmissionDetailView.as_view()

class EpisodeDetailView(DetailView, EmissionMixin):
    model = Episode

    def get_context_data(self, **kwargs):
        context = super(EpisodeDetailView, self).get_context_data(**kwargs)
        context['sectionName'] = "Emissions"
        context['diffusions'] = Diffusion.objects.select_related().filter(episode=self.object.id)
        context['soundfiles'] = SoundFile.objects.select_related().filter(episode=self.object.id)
        context['emission'] = Emission.objects.get(slug=self.kwargs.get('emission_slug'))
        context.update(self.get_emission_context(context['emission']))
        return context
episode = EpisodeDetailView.as_view()


class ProgramView(TemplateView):
    template_name = 'program.html'

    def get_context_data(self, year=None, week=None, **kwargs):
        context = super(ProgramView, self).get_context_data(**kwargs)
        context['sectionName'] = "Emissions"
        schedules = Schedule.objects.select_related().order_by('datetime')
        days = []
        for day in range(7):
            days.append({'schedules': [x for x in schedules if x.is_on_weekday(day+1)],
                         'datetime': datetime(2007, 1, day+1)})
        context['days'] = days
        context['weekday'] = datetime.today().weekday()
        context['week'] = week = int(week) if week is not None else datetime.today().isocalendar()[1]-1
        context['year'] = year = int(year) if year is not None else datetime.today().year
        context['week_first_day'] = datetime.strptime(str(year)+' '+str(week)+' 1', '%Y %U %w')
        context['week_last_day'] = context['week_first_day'] + timedelta(days=+6)
        context['week_previous'] =  context['week_first_day'] + timedelta(days=-7)
        context['week_next'] = context['week_last_day']
        return context

program = ProgramView.as_view()

class TimeCell:
    nonstop = None
    w = 1
    h = 1
    time_label = None

    def __init__(self, i, j):
        self.x = i
        self.y = j
        self.schedules = []

    def add_schedule(self, schedule):
        end_time = schedule.datetime + timedelta(
                minutes=schedule.get_duration())
        self.time_label = '%02d:%02d-%02d:%02d' % (
                schedule.datetime.hour,
                schedule.datetime.minute,
                end_time.hour,
                end_time.minute)
        self.schedules.append(schedule)

    def __unicode__(self):
        if self.schedules:
            return ', '.join([x.emission.title for x in self.schedules])
        else:
            return self.nonstop

    def __eq__(self, other):
        return (unicode(self) == unicode(other) and self.time_label == other.time_label)


class Grid(TemplateView):
    template_name = 'grid.html'

    def get_context_data(self, **kwargs):
        context = super(Grid, self).get_context_data(**kwargs)
        context['sectionName'] = "Emissions"

        nb_lines = 2 * 24 # the cells are half hours
        grid = []

        times = ['%02d:%02d' % (x/2, x%2*30) for x in range(nb_lines)]
        # start grid after the night programs
        times = times[2*Schedule.DAY_HOUR_START:] + times[:2*Schedule.DAY_HOUR_START]

        nonstops = []
        for nonstop in Nonstop.objects.all():
            if nonstop.start < nonstop.end:
                nonstops.append([nonstop.start.hour + nonstop.start.minute/60.,
                                 nonstop.end.hour + nonstop.end.minute/60.,
                                 nonstop.title])
            else:
                # crossing midnight
                nonstops.append([nonstop.start.hour + nonstop.start.minute/60.,
                                 24,
                                 nonstop.title])
                nonstops.append([0,
                                 nonstop.end.hour + nonstop.end.minute/60.,
                                 nonstop.title])
        nonstops.sort()

        for i in range(nb_lines):
            grid.append([])
            for j in range(7):
                grid[-1].append(TimeCell(i, j))

            nonstop = [x for x in nonstops if i>=x[0]*2 and i<x[1]*2][0]
            for time_cell in grid[-1]:
                time_cell.nonstop = nonstop[2]
                if nonstop[1] == 5:
                    # the one ending at 5am will be cut down, so we inscribe
                    # its duration manually
                    time_cell.time_label = '%02d:00-%02d:00' % (
                            nonstop[0], nonstop[1])

        for schedule in Schedule.objects.select_related().order_by('datetime'):
            row_start = schedule.datetime.hour * 2 + \
                    int(math.ceil(schedule.datetime.minute / 30))
            day_no = schedule.get_weekday()

            for step in range(int(math.ceil(schedule.get_duration() / 30.))):
                if grid[(row_start+step)%nb_lines][day_no] is None:
                    grid[(row_start+step)%nb_lines][day_no] = TimeCell()
                grid[(row_start+step)%nb_lines][day_no].add_schedule(schedule)

        # start grid after the night programs
        grid = grid[2*Schedule.DAY_HOUR_START:] + grid[:2*Schedule.DAY_HOUR_START]

        # look for the case where the same emission has different schedules for
        # the same time cell, for example if it lasts one hour the first week,
        # and two hours the third week.
        for i in range(nb_lines):
            grid[i] = [x for x in grid[i] if x is not None]
            for j, cell in enumerate(grid[i]):
                if grid[i][j] is None:
                    continue
                if len(grid[i][j].schedules) > 1:
                    time_cell_emissions = {}
                    for schedule in grid[i][j].schedules:
                        if not schedule.emission.id in time_cell_emissions:
                            time_cell_emissions[schedule.emission.id] = []
                        time_cell_emissions[schedule.emission.id].append(schedule)
                    for schedule_list in time_cell_emissions.values():
                        if len(schedule_list) == 1:
                            continue
                        # here it is, same cell, same emission, several
                        # schedules
                        schedule_list.sort(lambda x,y: -cmp(x.get_duration(), y.get_duration()))
                        for schedule in schedule_list[1:]:
                            grid[i][j].schedules.remove(schedule)
                            end_time = schedule.datetime + timedelta(minutes=schedule.get_duration())
                            schedule_list[0].time_label_extra = ', -%02d:%02d %s' % (
                                    end_time.hour, end_time.minute, schedule.weeks_string)

        # merge adjacent

        # 1st thing is to merge cells on the same line, this will mostly catch
        # consecutive nonstop cells
        for i in range(nb_lines):
            for j, cell in enumerate(grid[i]):
                if grid[i][j] is None:
                    continue
                t = 1
                try:
                    # if the cells are identical, they are removed from the
                    # grid, and current cell width is increased
                    while grid[i][j+t] == cell:
                        cell.w += 1
                        grid[i][j+t] = None
                        t += 1
                except IndexError:
                    pass

            # once we're done we remove empty cells
            grid[i] = [x for x in grid[i] if x is not None]

        # 2nd thing is to merge cells vertically, this is emissions that last
        # for more than 30 minutes
        for i in range(nb_lines):
            grid[i] = [x for x in grid[i] if x is not None]
            for j, cell in enumerate(grid[i]):
                if grid[i][j] is None:
                    continue
                t = 1
                try:
                    while True:
                        # we look if the next time cell has the same emissions
                        same_cell_below = [(bj, x) for bj, x in enumerate(grid[i+cell.h])
                                           if x == cell and x.y == cell.y and x.w == cell.w]
                        if same_cell_below:
                            # if the cell was identical, we remove it and
                            # increase current cell height
                            bj, same_cell_below = same_cell_below[0]
                            del grid[i+cell.h][bj]
                            cell.h += 1
                        else:
                            # if the cell is different, we have a closer look
                            # to it, so we can remove emissions that will
                            # already be mentioned in the current cell.
                            #
                            # For example:
                            #  - 7am30, seuls contre tout, 1h30
                            #  - 8am, du pied gauche & la voix de la rue, 1h
                            # should produce: (this is case A)
                            #  |      7:30-9:00      |
                            #  |  seuls contre tout  |
                            #  |---------------------|
                            #  |      8:00-9:00      |
                            #  |   du pied gauche    |
                            #  |  la voix de la rue  |
                            #
                            # On the other hand, if all three emissions started
                            # at 7am30, we want: (this is case B)
                            #  |      7:30-9:00      |
                            #  |  seuls contre tout  |
                            #  |   du pied gauche    |
                            #  |  la voix de la rue  |
                            # that is we merge all of them, ignoring the fact
                            # that the other emissions will stop at 8am30
                            current_cell_schedules = set(grid[i][j].schedules)
                            cursor = 1
                            while True and current_cell_schedules:
                                same_cell_below = [x for x in grid[i+cursor] if x.y == grid[i][j].y]
                                if not same_cell_below:
                                    cursor += 1
                                    continue
                                same_cell_below = same_cell_below[0]
                                if current_cell_schedules.issubset(same_cell_below.schedules):
                                    # this handles case A (see comment above)
                                    for schedule in current_cell_schedules:
                                        if schedule in same_cell_below.schedules:
                                            same_cell_below.schedules.remove(schedule)
                                elif same_cell_below.schedules and \
                                        current_cell_schedules.issuperset(same_cell_below.schedules):
                                    # this handles case B (see comment above)
                                    # we set the cell time label to the longest
                                    # period
                                    grid[i][j].time_label = same_cell_below.time_label
                                    # then we sort emissions so the longest are
                                    # put first
                                    grid[i][j].schedules.sort(
                                            lambda x, y: -cmp(x.get_duration(), y.get_duration()))
                                    # then we add individual time labels to the
                                    # other schedules
                                    for schedule in current_cell_schedules:
                                        if schedule not in same_cell_below.schedules:
                                            end_time = schedule.datetime + timedelta(
                                                    minutes=schedule.get_duration())
                                            schedule.time_label = '%02d:%02d-%02d:%02d' % (
                                                    schedule.datetime.hour,
                                                    schedule.datetime.minute,
                                                    end_time.hour,
                                                    end_time.minute)
                                    grid[i][j].h += 1
                                    grid[i+cursor].remove(same_cell_below)
                                cursor += 1
                            break
                except IndexError:
                    pass

        # cut night at 3am
        grid = grid[:42]
        times = times[:42]

        context['grid'] = grid
        context['times'] = times
        context['categories'] = Category.objects.all()
        context['weekdays'] = ['Lundi', 'Mardi', 'Mercredi', 'Jeudi',
                'Vendredi', 'Samedi', 'Dimanche']

        return context

grid = Grid.as_view()


class Home(TemplateView):
    template_name = 'home.html'

    def get_context_data(self, **kwargs):
        context = super(Home, self).get_context_data(**kwargs)
        context['sectionName'] = "Home"
        context['news'] = list(NewsItem.objects.all().exclude(image__isnull=True).exclude(image__exact='').order_by('-datetime')[:6])
        context['emissions'] = list(Emission.objects.filter(archived=False).order_by('title'))
        schedules = Schedule.objects.select_related().order_by('datetime')
        days = []
        for day in range(7):
            days.append({'schedules': [x for x in schedules if x.is_on_weekday(day+1)],
                         'datetime': datetime(2007, 1, day+1)})
        context['days'] = days
        return context

home = Home.as_view()

class NewsItemDetailView(DetailView):
    model = NewsItem
    def get_context_data(self, **kwargs):
        context['sectionName'] = "News"
        context = super(NewsItemDetailView, self).get_context_data(**kwargs)
        context['news'] = list(NewsItem.objects.all().order_by('-datetime')[:60])
        context['categories'] = list(NewsCategory.objects.all())
        return context
newsitem = NewsItemDetailView.as_view()

class News(TemplateView):
    template_name = 'news.html'

    def get_context_data(self, **kwargs):
        context = super(News, self).get_context_data(**kwargs)
        context['sectionName'] = "News"
        context['newsImaged'] = list(NewsItem.objects.all().exclude(image__isnull=True).exclude(image__exact='').order_by('-datetime')[:3])
        context['news'] = list(NewsItem.objects.all().order_by('-datetime')[:60])
        context['categories'] = list(NewsCategory.objects.all())
        return context

news = News.as_view()

class Emissions(TemplateView):
    template_name = 'emissions.html'

    def get_context_data(self, **kwargs):
        context = super(Emissions, self).get_context_data(**kwargs)
        context['sectionName'] = "Emissions"
        context['emissions'] = Emission.objects.prefetch_related('categories').filter(archived=False).order_by('title')
        context['categories'] = Category.objects.all()
        return context

emissions = Emissions.as_view()

class Archives(TemplateView):
    template_name = 'archives.html'
    def get_context_data(self, **kwargs):
        context = super(Archives, self).get_context_data(**kwargs)
        context['sectionName'] = "Emissions"
        context['emissions'] = Emission.objects.all().filter(archived=True).order_by('title')
        return context

archives = Archives.as_view()

class Get(TemplateView):
    template_name = 'get.html'
    def get_context_data(self, **kwargs):
        context = super(Get, self).get_context_data(**kwargs)
        context['emissions'] = Emission.objects.all().order_by('title')
        return context

get = Get.as_view()

class Listen(TemplateView):
    template_name = 'listen.html'

    def get_context_data(self, **kwargs):
        context = super(Listen, self).get_context_data(**kwargs)
        context['sectionName'] = "Listen"
        context['episodes'] = Episode.objects.filter(
                soundfile__podcastable=True, soundfile__fragment=False) \
                .select_related().extra(select={
                    'first_diffusion': 'emissions_diffusion.datetime', },
                    select_params=(False, True),
                    where=['''datetime = (SELECT MIN(datetime)
                                            FROM emissions_diffusion
                                        WHERE episode_id = emissions_episode.id)'''],
                    tables=['emissions_diffusion'],).order_by('-first_diffusion') [:60]

        # get all related soundfiles in a single query
        soundfiles = {}
        for soundfile in SoundFile.objects.select_related().filter(podcastable=True,
                fragment=False, episode__in=[x.id for x in context['episodes']]):
            soundfiles[soundfile.episode_id] = soundfile

        # replace dynamic property by a static attribute, to avoid database
        # lookups
        for episode in context['episodes']:
            episode.main_sound = soundfiles.get(episode.id)

        return context

listen = Listen.as_view()


@cache_control(max_age=25)
@csrf_exempt
@to_json('api')
def onair(request):
    d = whatsonair()
    if d.get('episode'):
        d['episode'] = {
            'title': d['episode'].title,
            'url': d['episode'].get_absolute_url()
        }
    if d.get('emission'):
        d['emission'] = {
            'title': d['emission'].title,
            'url': d['emission'].get_absolute_url()
        }
    if d.get('nonstop'):
        d['nonstop'] = {
            'title': d['nonstop'].title,
        }
    if d.get('current_slot'):
        del d['current_slot']
    return d


class NewsItemDetailView(DetailView):
    model = NewsItem

newsitem = NewsItemDetailView.as_view()