import logging

from django import forms
from django.conf import settings
from django.contrib import messages
from django.db.models import Count, Q
from django.shortcuts import get_object_or_404, redirect
from django.urls import reverse
from django.utils.safestring import mark_safe
from django.views.generic import DetailView, ListView, TemplateView
from django.views.generic.edit import CreateView, DeleteView, FormView, UpdateView

from camps.mixins import CampViewMixin
from program.autoscheduler import AutoScheduler
from program.mixins import AvailabilityMatrixViewMixin
from program.models import (
    Event,
    EventLocation,
    EventProposal,
    EventSession,
    EventSlot,
    EventType,
    Speaker,
    SpeakerProposal,
)
from program.utils import save_speaker_availability

from ..forms import (
    AutoScheduleApplyForm,
    AutoScheduleValidateForm,
    EventScheduleForm,
    SpeakerForm,
)
from ..mixins import ContentTeamPermissionMixin

logger = logging.getLogger("bornhack.%s" % __name__)


#######################################
# MANAGE SPEAKER/EVENT PROPOSAL VIEWS


class PendingProposalsView(CampViewMixin, ContentTeamPermissionMixin, ListView):
    """This convenience view shows a list of pending proposals"""

    model = SpeakerProposal
    template_name = "pending_proposals.html"
    context_object_name = "speaker_proposal_list"

    def get_queryset(self, **kwargs):
        qs = super().get_queryset(**kwargs).filter(proposal_status="pending")
        qs = qs.prefetch_related("user", "urls", "speaker")
        return qs

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context["event_proposal_list"] = self.camp.event_proposals.filter(
            proposal_status=EventProposal.PROPOSAL_PENDING
        ).prefetch_related("event_type", "track", "speakers", "tags", "user", "event")
        return context


class ProposalApproveBaseView(CampViewMixin, ContentTeamPermissionMixin, UpdateView):
    """
    Shared logic between SpeakerProposalApproveView and EventProposalApproveView
    """

    fields = ["reason"]

    def form_valid(self, form):
        """
        We have two submit buttons in this form, Approve and Reject
        """
        if "approve" in form.data:
            # approve button was pressed
            form.instance.mark_as_approved(self.request)
        elif "reject" in form.data:
            # reject button was pressed
            form.instance.mark_as_rejected(self.request)
        else:
            messages.error(self.request, "Unknown submit action")
        return redirect(
            reverse(
                "backoffice:pending_proposals", kwargs={"camp_slug": self.camp.slug}
            )
        )


class SpeakerProposalListView(CampViewMixin, ContentTeamPermissionMixin, ListView):
    """This view permits Content Team members to list SpeakerProposals"""

    model = SpeakerProposal
    template_name = "speaker_proposal_list.html"
    context_object_name = "speaker_proposal_list"

    def get_queryset(self, **kwargs):
        qs = super().get_queryset(**kwargs)
        qs = qs.prefetch_related("user", "urls", "speaker")
        return qs


class SpeakerProposalDetailView(
    AvailabilityMatrixViewMixin,
    ContentTeamPermissionMixin,
    DetailView,
):
    """This view permits Content Team members to see SpeakerProposal details"""

    model = SpeakerProposal
    template_name = "speaker_proposal_detail_backoffice.html"
    context_object_name = "speaker_proposal"

    def get_queryset(self, *args, **kwargs):
        qs = super().get_queryset(*args, **kwargs)
        qs = qs.prefetch_related("user", "urls")
        return qs


class SpeakerProposalApproveRejectView(ProposalApproveBaseView):
    """This view allows ContentTeam members to approve/reject SpeakerProposals"""

    model = SpeakerProposal
    template_name = "speaker_proposal_approve_reject.html"
    context_object_name = "speaker_proposal"


class EventProposalListView(CampViewMixin, ContentTeamPermissionMixin, ListView):
    """This view permits Content Team members to list EventProposals"""

    model = EventProposal
    template_name = "event_proposal_list.html"
    context_object_name = "event_proposal_list"

    def get_queryset(self, *args, **kwargs):
        qs = super().get_queryset(*args, **kwargs)
        qs = qs.prefetch_related(
            "user",
            "urls",
            "event",
            "event_type",
            "speakers__event_proposals",
            "track",
            "tags",
        )
        return qs


class EventProposalDetailView(CampViewMixin, ContentTeamPermissionMixin, DetailView):
    """This view permits Content Team members to see EventProposal details"""

    model = EventProposal
    template_name = "event_proposal_detail_backoffice.html"
    context_object_name = "event_proposal"


class EventProposalApproveRejectView(ProposalApproveBaseView):
    """This view allows ContentTeam members to approve/reject EventProposals"""

    model = EventProposal
    template_name = "event_proposal_approve_reject.html"
    context_object_name = "event_proposal"


################################
# MANAGE SPEAKER VIEWS


class SpeakerListView(CampViewMixin, ContentTeamPermissionMixin, ListView):
    """This view is used by the Content Team to see Speaker objects."""

    model = Speaker
    template_name = "speaker_list_backoffice.html"

    def get_queryset(self, *args, **kwargs):
        qs = super().get_queryset(*args, **kwargs)
        qs = qs.prefetch_related(
            "proposal__user",
            "events__event_slots",
            "events__event_type",
            "event_conflicts",
        )
        return qs


class SpeakerDetailView(
    AvailabilityMatrixViewMixin, ContentTeamPermissionMixin, DetailView
):
    """This view is used by the Content Team to see details for Speaker objects"""

    model = Speaker
    template_name = "speaker_detail_backoffice.html"

    def get_queryset(self, *args, **kwargs):
        qs = super().get_queryset(*args, **kwargs)
        qs = qs.prefetch_related(
            "event_conflicts", "events__event_slots", "events__event_type"
        )
        return qs


class SpeakerUpdateView(
    AvailabilityMatrixViewMixin, ContentTeamPermissionMixin, UpdateView
):
    """This view is used by the Content Team to update Speaker objects"""

    model = Speaker
    template_name = "speaker_update.html"
    form_class = SpeakerForm

    def get_form_kwargs(self):
        """Set camp for the form"""
        kwargs = super().get_form_kwargs()
        kwargs.update({"camp": self.camp})
        return kwargs

    def form_valid(self, form):
        """Save object and availability"""
        speaker = form.save()
        save_speaker_availability(form, obj=speaker)
        messages.success(self.request, "Speaker has been updated")
        return redirect(
            reverse(
                "backoffice:speaker_detail",
                kwargs={"camp_slug": self.camp.slug, "slug": self.get_object().slug},
            )
        )


class SpeakerDeleteView(CampViewMixin, ContentTeamPermissionMixin, DeleteView):
    """This view is used by the Content Team to delete Speaker objects"""

    model = Speaker
    template_name = "speaker_delete.html"

    def delete(self, *args, **kwargs):
        speaker = self.get_object()
        # delete related objects first
        speaker.availabilities.all().delete()
        speaker.urls.all().delete()
        return super().delete(*args, **kwargs)

    def get_success_url(self):
        messages.success(
            self.request, f"Speaker '{self.get_object().name}' has been deleted"
        )
        return reverse("backoffice:speaker_list", kwargs={"camp_slug": self.camp.slug})


################################
# MANAGE EVENTTYPE VIEWS


class EventTypeListView(CampViewMixin, ContentTeamPermissionMixin, ListView):
    """This view is used by the Content Team to list EventTypes"""

    model = EventType
    template_name = "event_type_list.html"
    context_object_name = "event_type_list"

    def get_queryset(self, *args, **kwargs):
        qs = super().get_queryset(*args, **kwargs)
        qs = qs.annotate(
            # only count events for the current camp
            event_count=Count(
                "events", distinct=True, filter=Q(events__track__camp=self.camp)
            ),
            # only count EventSessions for the current camp
            event_sessions_count=Count(
                "event_sessions",
                distinct=True,
                filter=Q(event_sessions__camp=self.camp),
            ),
            # only count EventSlots for the current camp
            event_slots_count=Count(
                "event_sessions__event_slots",
                distinct=True,
                filter=Q(event_sessions__camp=self.camp),
            ),
        )
        return qs


class EventTypeDetailView(CampViewMixin, ContentTeamPermissionMixin, DetailView):
    """This view is used by the Content Team to see details for EventTypes"""

    model = EventType
    template_name = "event_type_detail.html"
    context_object_name = "event_type"

    def get_context_data(self, *args, **kwargs):
        context = super().get_context_data(*args, **kwargs)
        context["event_sessions"] = self.camp.event_sessions.filter(
            event_type=self.get_object()
        ).prefetch_related("event_location", "event_slots")
        context["events"] = self.camp.events.filter(
            event_type=self.get_object()
        ).prefetch_related(
            "speakers", "event_slots__event_session__event_location", "event_type"
        )
        return context


################################
# MANAGE EVENTLOCATION VIEWS


class EventLocationListView(CampViewMixin, ContentTeamPermissionMixin, ListView):
    """This view is used by the Content Team to list EventLocation objects."""

    model = EventLocation
    template_name = "event_location_list.html"
    context_object_name = "event_location_list"

    def get_queryset(self, *args, **kwargs):
        qs = super().get_queryset(*args, **kwargs)
        qs = qs.prefetch_related("event_sessions__event_slots", "conflicts")
        return qs


class EventLocationDetailView(CampViewMixin, ContentTeamPermissionMixin, DetailView):
    """This view is used by the Content Team to see details for EventLocation objects"""

    model = EventLocation
    template_name = "event_location_detail.html"
    context_object_name = "event_location"

    def get_queryset(self, *args, **kwargs):
        qs = super().get_queryset(*args, **kwargs)
        qs = qs.prefetch_related(
            "conflicts", "event_sessions__event_slots", "event_sessions__event_type"
        )
        return qs


class EventLocationCreateView(CampViewMixin, ContentTeamPermissionMixin, CreateView):
    """This view is used by the Content Team to create EventLocation objects"""

    model = EventLocation
    fields = ["name", "icon", "capacity", "conflicts"]
    template_name = "event_location_form.html"

    def get_form(self, *args, **kwargs):
        form = super().get_form(*args, **kwargs)
        form.fields["conflicts"].queryset = self.camp.event_locations.all()
        return form

    def form_valid(self, form):
        location = form.save(commit=False)
        location.camp = self.camp
        location.save()
        form.save_m2m()
        messages.success(
            self.request, f"EventLocation {location.name} has been created"
        )
        return redirect(
            reverse(
                "backoffice:event_location_detail",
                kwargs={"camp_slug": self.camp.slug, "slug": location.slug},
            )
        )


class EventLocationUpdateView(CampViewMixin, ContentTeamPermissionMixin, UpdateView):
    """This view is used by the Content Team to update EventLocation objects"""

    model = EventLocation
    fields = ["name", "icon", "capacity", "conflicts"]
    template_name = "event_location_form.html"

    def get_form(self, *args, **kwargs):
        form = super().get_form(*args, **kwargs)
        form.fields["conflicts"].queryset = self.camp.event_locations.exclude(
            pk=self.get_object().pk
        )
        return form

    def get_success_url(self):
        messages.success(
            self.request, f"EventLocation {self.get_object().name} has been updated"
        )
        return reverse(
            "backoffice:event_location_detail",
            kwargs={"camp_slug": self.camp.slug, "slug": self.get_object().slug},
        )


class EventLocationDeleteView(CampViewMixin, ContentTeamPermissionMixin, DeleteView):
    """This view is used by the Content Team to delete EventLocation objects"""

    model = EventLocation
    template_name = "event_location_delete.html"
    context_object_name = "event_location"

    def delete(self, *args, **kwargs):
        slotsdeleted, slotdetails = self.get_object().event_slots.all().delete()
        sessionsdeleted, sessiondetails = (
            self.get_object().event_sessions.all().delete()
        )

        return super().delete(*args, **kwargs)

    def get_success_url(self):
        messages.success(
            self.request, f"EventLocation '{self.get_object().name}' has been deleted."
        )
        return reverse(
            "backoffice:event_location_list", kwargs={"camp_slug": self.camp.slug}
        )


################################
# MANAGE EVENT VIEWS


class EventListView(CampViewMixin, ContentTeamPermissionMixin, ListView):
    """This view is used by the Content Team to see Event objects."""

    model = Event
    template_name = "event_list_backoffice.html"

    def get_queryset(self, *args, **kwargs):
        qs = super().get_queryset(*args, **kwargs)
        qs = qs.prefetch_related(
            "speakers__events",
            "event_type",
            "event_slots__event_session__event_location",
            "tags",
        )
        return qs


class EventDetailView(CampViewMixin, ContentTeamPermissionMixin, DetailView):
    """This view is used by the Content Team to see details for Event objects"""

    model = Event
    template_name = "event_detail_backoffice.html"


class EventUpdateView(CampViewMixin, ContentTeamPermissionMixin, UpdateView):
    """This view is used by the Content Team to update Event objects"""

    model = Event
    fields = [
        "title",
        "abstract",
        "video_recording",
        "duration_minutes",
        "demand",
        "tags",
    ]
    template_name = "event_update.html"

    def get_success_url(self):
        messages.success(self.request, "Event has been updated")
        return reverse(
            "backoffice:event_detail",
            kwargs={"camp_slug": self.camp.slug, "slug": self.get_object().slug},
        )


class EventDeleteView(CampViewMixin, ContentTeamPermissionMixin, DeleteView):
    """This view is used by the Content Team to delete Event objects"""

    model = Event
    template_name = "event_delete.html"

    def delete(self, *args, **kwargs):
        self.get_object().urls.all().delete()
        return super().delete(*args, **kwargs)

    def get_success_url(self):
        messages.success(
            self.request,
            f"Event '{self.get_object().title}' has been deleted!",
        )
        return reverse("backoffice:event_list", kwargs={"camp_slug": self.camp.slug})


class EventScheduleView(CampViewMixin, ContentTeamPermissionMixin, FormView):
    """This view is used by the Content Team to manually schedule Events.
    It shows a table with radioselect buttons for the available slots for the
    EventType of the Event"""

    form_class = EventScheduleForm
    template_name = "event_schedule.html"

    def setup(self, *args, **kwargs):
        super().setup(*args, **kwargs)
        self.event = get_object_or_404(
            Event, track__camp=self.camp, slug=kwargs["slug"]
        )

    def get_form(self, *args, **kwargs):
        form = super().get_form(*args, **kwargs)
        self.slots = []
        slotindex = 0
        # loop over sessions, get free slots
        for session in self.camp.event_sessions.filter(
            event_type=self.event.event_type,
            event_duration_minutes__gte=self.event.duration_minutes,
        ):
            for slot in session.get_available_slots():
                # loop over speakers to see if they are all available
                for speaker in self.event.speakers.all():
                    if not speaker.is_available(slot.when):
                        # this speaker is not available, skip this slot
                        break
                else:
                    # all speakers are available for this slot
                    self.slots.append({"index": slotindex, "slot": slot})
                    slotindex += 1
        # add the slot choicefield
        form.fields["slot"] = forms.ChoiceField(
            widget=forms.RadioSelect,
            choices=[(s["index"], s["index"]) for s in self.slots],
        )
        return form

    def get_context_data(self, *args, **kwargs):
        """
        Add event to context
        """
        context = super().get_context_data(*args, **kwargs)
        context["event"] = self.event
        context["event_slots"] = self.slots
        return context

    def form_valid(self, form):
        """
        Set needed values, save slot and return
        """
        slot = self.slots[int(form.cleaned_data["slot"])]["slot"]
        slot.event = self.event
        slot.autoscheduled = False
        slot.save()
        messages.success(
            self.request,
            f"{self.event.title} has been scheduled to begin at {slot.when.lower} at location {slot.event_location.name} successfully!",
        )
        return redirect(
            reverse(
                "backoffice:event_detail",
                kwargs={"camp_slug": self.camp.slug, "slug": self.event.slug},
            )
        )


################################
# MANAGE EVENTSESSION VIEWS


class EventSessionCreateTypeSelectView(
    CampViewMixin, ContentTeamPermissionMixin, ListView
):
    """
    This view is shown first when creating a new EventSession
    """

    model = EventType
    template_name = "event_session_create_type_select.html"
    context_object_name = "event_type_list"


class EventSessionCreateLocationSelectView(
    CampViewMixin, ContentTeamPermissionMixin, ListView
):
    """
    This view is shown second when creating a new EventSession
    """

    model = EventLocation
    template_name = "event_session_create_location_select.html"
    context_object_name = "event_location_list"

    def setup(self, *args, **kwargs):
        super().setup(*args, **kwargs)
        self.event_type = get_object_or_404(EventType, slug=kwargs["event_type_slug"])

    def get_context_data(self, *args, **kwargs):
        """
        Add event_type to context
        """
        context = super().get_context_data(*args, **kwargs)
        context["event_type"] = self.event_type
        return context


class EventSessionFormViewMixin:
    """
    A mixin with the stuff shared between EventSession{Create|Update}View
    """

    def get_form(self, *args, **kwargs):
        """
        The default range widgets are a bit shit because they eat the help_text and
        have no indication of which field is for what. So we add a nice placeholder.
        We also limit the event_location dropdown to only the current camps locations.
        """
        form = super().get_form(*args, **kwargs)
        form.fields["when"].widget.widgets[0].attrs = {
            "placeholder": f"Start Date and Time (YYYY-MM-DD HH:MM). Time zone is {settings.TIME_ZONE}.",
        }
        form.fields["when"].widget.widgets[1].attrs = {
            "placeholder": f"End Date and Time (YYYY-MM-DD HH:MM). Time zone is {settings.TIME_ZONE}.",
        }
        if hasattr(form.fields, "event_location"):
            form.fields["event_location"].queryset = EventLocation.objects.filter(
                camp=self.camp
            )
        return form

    def get_context_data(self, *args, **kwargs):
        """
        Add event_type and location and existing sessions to context
        """
        context = super().get_context_data(*args, **kwargs)
        if not hasattr(self, "event_type"):
            self.event_type = self.get_object().event_type
        context["event_type"] = self.event_type

        if not hasattr(self, "event_location"):
            self.event_location = self.get_object().event_location
        context["event_location"] = self.event_location

        context["sessions"] = self.event_type.event_sessions.filter(camp=self.camp)
        return context


class EventSessionCreateView(
    CampViewMixin, ContentTeamPermissionMixin, EventSessionFormViewMixin, CreateView
):
    """
    This view is used by the Content Team to create EventSession objects
    """

    model = EventSession
    fields = ["description", "when", "event_duration_minutes"]
    template_name = "event_session_form.html"

    def setup(self, *args, **kwargs):
        super().setup(*args, **kwargs)
        self.event_type = get_object_or_404(EventType, slug=kwargs["event_type_slug"])
        self.event_location = get_object_or_404(
            EventLocation, camp=self.camp, slug=kwargs["event_location_slug"]
        )

    def form_valid(self, form):
        """
        Set camp and event_type, check for overlaps and save
        """
        session = form.save(commit=False)
        session.event_type = self.event_type
        session.event_location = self.event_location
        session.camp = self.camp
        session.save()
        messages.success(self.request, f"{session} has been created successfully!")
        return redirect(
            reverse(
                "backoffice:event_session_list", kwargs={"camp_slug": self.camp.slug}
            )
        )


class EventSessionListView(CampViewMixin, ContentTeamPermissionMixin, ListView):
    """
    This view is used by the Content Team to see EventSession objects.
    """

    model = EventSession
    template_name = "event_session_list.html"
    context_object_name = "event_session_list"

    def get_queryset(self, *args, **kwargs):
        qs = super().get_queryset(*args, **kwargs)
        qs = qs.prefetch_related("event_type", "event_location", "event_slots")
        return qs


class EventSessionDetailView(CampViewMixin, ContentTeamPermissionMixin, DetailView):
    """
    This view is used by the Content Team to see details for EventSession objects
    """

    model = EventSession
    template_name = "event_session_detail.html"
    context_object_name = "session"


class EventSessionUpdateView(
    CampViewMixin, ContentTeamPermissionMixin, EventSessionFormViewMixin, UpdateView
):
    """
    This view is used by the Content Team to update EventSession objects
    """

    model = EventSession
    fields = ["when", "description", "event_duration_minutes"]
    template_name = "event_session_form.html"

    def form_valid(self, form):
        """
        Just save, we have a post_save signal which takes care of fixing EventSlots
        """
        session = form.save()
        messages.success(self.request, f"{session} has been updated successfully!")
        return redirect(
            reverse(
                "backoffice:event_session_list", kwargs={"camp_slug": self.camp.slug}
            )
        )


class EventSessionDeleteView(CampViewMixin, ContentTeamPermissionMixin, DeleteView):
    """
    This view is used by the Content Team to delete EventSession objects
    """

    model = EventSession
    template_name = "event_session_delete.html"
    context_object_name = "session"

    def get(self, *args, **kwargs):
        """Show a warning if we have something scheduled in this EventSession"""
        if self.get_object().event_slots.filter(event__isnull=False).exists():
            messages.warning(
                self.request,
                "NOTE: One or more EventSlots in this EventSession has an Event scheduled. Make sure you are deleting the correct session!",
            )
        return super().get(*args, **kwargs)

    def delete(self, *args, **kwargs):
        session = self.get_object()
        session.event_slots.all().delete()
        return super().delete(*args, **kwargs)

    def get_success_url(self):
        messages.success(
            self.request,
            "EventSession and related EventSlots was deleted successfully!",
        )
        return reverse(
            "backoffice:event_session_list", kwargs={"camp_slug": self.camp.slug}
        )


################################
# MANAGE EVENTSLOT VIEWS


class EventSlotListView(CampViewMixin, ContentTeamPermissionMixin, ListView):
    """This view is used by the Content Team to see EventSlot objects."""

    model = EventSlot
    template_name = "event_slot_list.html"
    context_object_name = "event_slot_list"

    def get_queryset(self, *args, **kwargs):
        qs = super().get_queryset(*args, **kwargs)
        qs = qs.prefetch_related(
            "event__speakers",
            "event_session__event_location",
            "event_session__event_type",
        )
        return qs


class EventSlotDetailView(CampViewMixin, ContentTeamPermissionMixin, DetailView):
    """This view is used by the Content Team to see details for EventSlot objects"""

    model = EventSlot
    template_name = "event_slot_detail.html"
    context_object_name = "event_slot"


class EventSlotUnscheduleView(CampViewMixin, ContentTeamPermissionMixin, UpdateView):
    """This view is used by the Content Team to remove an Event from the schedule/EventSlot"""

    model = EventSlot
    template_name = "event_slot_unschedule.html"
    fields = []
    context_object_name = "event_slot"

    def form_valid(self, form):
        event_slot = self.get_object()
        event = event_slot.event
        event_slot.unschedule()
        messages.success(
            self.request,
            f"The Event '{event.title}' has been removed from the slot {event_slot}",
        )
        return redirect(
            reverse(
                "backoffice:event_detail",
                kwargs={"camp_slug": self.camp.slug, "slug": event.slug},
            )
        )


################################
# AUTOSCHEDULER VIEWS


class AutoScheduleManageView(CampViewMixin, ContentTeamPermissionMixin, TemplateView):
    """Just an index type view with links to the various actions"""

    template_name = "autoschedule_index.html"


class AutoScheduleCrashCourseView(
    CampViewMixin, ContentTeamPermissionMixin, TemplateView
):
    """A short crash course on the autoscheduler"""

    template_name = "autoschedule_crash_course.html"


class AutoScheduleValidateView(CampViewMixin, ContentTeamPermissionMixin, FormView):
    """This view is used to validate schedules. It uses the AutoScheduler and can
    either validate the currently applied schedule or a new similar schedule, or a
    brand new schedule"""

    template_name = "autoschedule_validate.html"
    form_class = AutoScheduleValidateForm

    def form_valid(self, form):
        # initialise AutoScheduler
        scheduler = AutoScheduler(camp=self.camp)

        # get autoschedule
        if form.cleaned_data["schedule"] == "current":
            autoschedule = scheduler.build_current_autoschedule()
            message = f"The currently scheduled Events form a valid schedule! AutoScheduler has {len(scheduler.autoslots)} Slots based on {scheduler.event_sessions.count()} EventSessions for {scheduler.event_types.count()} EventTypes. {scheduler.events.count()} Events in the schedule."
        elif form.cleaned_data["schedule"] == "similar":
            original_autoschedule = scheduler.build_current_autoschedule()
            autoschedule, diff = scheduler.calculate_similar_autoschedule(
                original_autoschedule
            )
            message = f"The new similar schedule is valid! AutoScheduler has {len(scheduler.autoslots)} Slots based on {scheduler.event_sessions.count()} EventSessions for {scheduler.event_types.count()} EventTypes. Differences to the current schedule: {len(diff['event_diffs'])} Event diffs and {len(diff['slot_diffs'])} Slot diffs."
        elif form.cleaned_data["schedule"] == "new":
            autoschedule = scheduler.calculate_autoschedule()
            message = f"The new schedule is valid! AutoScheduler has {len(scheduler.autoslots)} Slots based on {scheduler.event_sessions.count()} EventSessions for {scheduler.event_types.count()} EventTypes. {scheduler.events.count()} Events in the schedule."

        # check validity
        valid, violations = scheduler.is_valid(autoschedule, return_violations=True)
        if valid:
            messages.success(self.request, message)
        else:
            messages.error(self.request, "Schedule is NOT valid!")
            message = "Schedule violations:<br>"
            for v in violations:
                message += v + "<br>"
            messages.error(self.request, mark_safe(message))
        return redirect(
            reverse(
                "backoffice:autoschedule_validate", kwargs={"camp_slug": self.camp.slug}
            )
        )


class AutoScheduleDiffView(CampViewMixin, ContentTeamPermissionMixin, TemplateView):
    template_name = "autoschedule_diff.html"

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        scheduler = AutoScheduler(camp=self.camp)
        autoschedule, diff = scheduler.calculate_similar_autoschedule()
        context["diff"] = diff
        context["scheduler"] = scheduler
        return context


class AutoScheduleApplyView(CampViewMixin, ContentTeamPermissionMixin, FormView):
    """This view is used by the Content Team to apply a new schedules by unscheduling
    all autoscheduled Events, and scheduling all Event/Slot combinations in the schedule.

    TODO: see comment in program.autoscheduler.AutoScheduler.apply() method.
    """

    template_name = "autoschedule_apply.html"
    form_class = AutoScheduleApplyForm

    def form_valid(self, form):
        # initialise AutoScheduler
        scheduler = AutoScheduler(camp=self.camp)

        # get autoschedule
        if form.cleaned_data["schedule"] == "similar":
            autoschedule, diff = scheduler.calculate_similar_autoschedule()
        elif form.cleaned_data["schedule"] == "new":
            autoschedule = scheduler.calculate_autoschedule()

        # check validity
        valid, violations = scheduler.is_valid(autoschedule, return_violations=True)
        if valid:
            # schedule is valid, apply it
            deleted, created = scheduler.apply(autoschedule)
            messages.success(
                self.request,
                f"Schedule has been applied! {deleted} Events removed from schedule, {created} new Events scheduled. Differences to the previous schedule: {len(diff['event_diffs'])} Event diffs and {len(diff['slot_diffs'])} Slot diffs.",
            )
        else:
            messages.error(self.request, "Schedule is NOT valid, cannot apply!")
        return redirect(
            reverse(
                "backoffice:autoschedule_apply", kwargs={"camp_slug": self.camp.slug}
            )
        )


class AutoScheduleDebugEventSlotUnavailabilityView(
    CampViewMixin, ContentTeamPermissionMixin, TemplateView
):
    template_name = "autoschedule_debug_slots.html"

    def get_context_data(self, **kwargs):
        scheduler = AutoScheduler(camp=self.camp)
        context = {
            "scheduler": scheduler,
        }
        return context


class AutoScheduleDebugEventConflictsView(
    CampViewMixin, ContentTeamPermissionMixin, TemplateView
):
    template_name = "autoschedule_debug_events.html"

    def get_context_data(self, **kwargs):
        scheduler = AutoScheduler(camp=self.camp)
        context = {
            "scheduler": scheduler,
        }
        return context