from __future__ import absolute_import, unicode_literals

import logging

from django.conf import settings
from django.contrib import messages
from django.core.exceptions import PermissionDenied
from django.core.urlresolvers import reverse
from django.http import HttpResponseRedirect
from django.shortcuts import get_object_or_404, render_to_response
from django.template import RequestContext
from django.utils.translation import ugettext_lazy as _

from acls.models import AccessControlList
from common.utils import encapsulate
from common.views import AssignRemoveView, SingleObjectListView
from common.widgets import two_state_template
from documents.models import Document, DocumentType
from documents.permissions import permission_document_view
from documents.views import document_list
from permissions import Permission

from .forms import SmartLinkConditionForm, SmartLinkForm
from .models import ResolvedSmartLink, SmartLink, SmartLinkCondition
from .permissions import (
    permission_smart_link_create, permission_smart_link_delete,
    permission_smart_link_edit, permission_smart_link_view
)

logger = logging.getLogger(__name__)


class SetupSmartLinkDocumentTypesView(AssignRemoveView):
    decode_content_type = True
    left_list_title = _('Available document types')
    right_list_title = _('Document types enabled')
    object_permission = permission_smart_link_edit

    def add(self, item):
        self.get_object().document_types.add(item)

    def get_object(self):
        return get_object_or_404(SmartLink, pk=self.kwargs['pk'])

    def left_list(self):
        return AssignRemoveView.generate_choices(DocumentType.objects.exclude(pk__in=self.get_object().document_types.all()))

    def right_list(self):
        return AssignRemoveView.generate_choices(self.get_object().document_types.all())

    def remove(self, item):
        self.get_object().document_types.remove(item)

    def get_context_data(self, **kwargs):
        data = super(SetupSmartLinkDocumentTypesView, self).get_context_data(**kwargs)
        data.update({
            'object': self.get_object(),
            'title': _('Document type for which to enable smart link: %s') % self.get_object(),
        })

        return data


def smart_link_instance_view(request, document_id, smart_link_pk):
    document = get_object_or_404(Document, pk=document_id)
    smart_link = get_object_or_404(SmartLink, pk=smart_link_pk)

    try:
        Permission.check_permissions(request.user, [permission_smart_link_view])
    except PermissionDenied:
        AccessControlList.objects.check_access(permission_smart_link_view, request.user, smart_link)

    try:
        object_list = smart_link.get_linked_document_for(document)
    except Exception as exception:
        object_list = Document.objects.none()

        if request.user.is_staff or request.user.is_superuser:
            messages.error(request, _('Smart link query error: %s' % exception))

    return document_list(
        request,
        title=_('Documents in smart link: %s') % smart_link.get_dynamic_title(document),
        object_list=object_list,
        extra_context={
            'object': document
        }
    )


class SmartLinkListView(SingleObjectListView):
    object_permission = permission_smart_link_view

    def get_queryset(self):
        self.queryset = self.get_smart_link_queryset()
        return super(SmartLinkListView, self).get_queryset()

    def get_smart_link_queryset(self):
        return SmartLink.objects.all()

    def get_extra_context(self):
        return {
            'extra_columns': [
                {'name': _('Dynamic title'), 'attribute': 'dynamic_title'},
                {'name': _('Enabled'), 'attribute': encapsulate(lambda instance: two_state_template(instance.enabled))},
            ],
            'hide_link': True,
            'title': _('Smart links'),
        }


class DocumentSmartLinkListView(SmartLinkListView):
    def dispatch(self, request, *args, **kwargs):
        self.document = get_object_or_404(Document, pk=self.kwargs['pk'])

        try:
            Permission.check_permissions(request.user, (permission_document_view,))
        except PermissionDenied:
            AccessControlList.objects.check_permissions(permission_document_view, request.user, self.document)

        return super(DocumentSmartLinkListView, self).dispatch(request, *args, **kwargs)

    def get_smart_link_queryset(self):
        return ResolvedSmartLink.objects.filter(document_types=self.document.document_type, enabled=True)

    def get_extra_context(self):
        return {
            'document': self.document,
            'extra_columns': (
                {'name': _('Title'), 'attribute': encapsulate(lambda smart_link: smart_link.get_dynamic_title(self.document))},
            ),
            'hide_object': True,
            'hide_link': True,
            'object': self.document,
            'title': _('Smart links for document: %s') % self.document,
        }


def smart_link_create(request):
    Permission.check_permissions(request.user, [permission_smart_link_create])

    if request.method == 'POST':
        form = SmartLinkForm(request.POST)
        if form.is_valid():
            document_group = form.save()
            messages.success(request, _('Smart link: %s created successfully.') % document_group)
            return HttpResponseRedirect(reverse('linking:smart_link_list'))
    else:
        form = SmartLinkForm()

    return render_to_response('appearance/generic_form.html', {
        'form': form,
        'title': _('Create new smart link')
    }, context_instance=RequestContext(request))


def smart_link_edit(request, smart_link_pk):
    smart_link = get_object_or_404(SmartLink, pk=smart_link_pk)

    try:
        Permission.check_permissions(request.user, [permission_smart_link_edit])
    except PermissionDenied:
        AccessControlList.objects.check_access(permission_smart_link_edit, request.user, smart_link)

    if request.method == 'POST':
        form = SmartLinkForm(request.POST, instance=smart_link)
        if form.is_valid():
            smart_link = form.save()
            messages.success(request, _('Smart link: %s edited successfully.') % smart_link)
            return HttpResponseRedirect(reverse('linking:smart_link_list'))
    else:
        form = SmartLinkForm(instance=smart_link)

    return render_to_response('appearance/generic_form.html', {
        'object': smart_link,
        'form': form,
        'title': _('Edit smart link: %s') % smart_link
    }, context_instance=RequestContext(request))


def smart_link_delete(request, smart_link_pk):
    smart_link = get_object_or_404(SmartLink, pk=smart_link_pk)

    try:
        Permission.check_permissions(request.user, [permission_smart_link_delete])
    except PermissionDenied:
        AccessControlList.objects.check_access(permission_smart_link_delete, request.user, smart_link)

    next = request.POST.get('next', request.GET.get('next', request.META.get('HTTP_REFERER', reverse(settings.LOGIN_REDIRECT_URL))))
    previous = request.POST.get('previous', request.GET.get('previous', request.META.get('HTTP_REFERER', reverse(settings.LOGIN_REDIRECT_URL))))

    if request.method == 'POST':
        try:
            smart_link.delete()
            messages.success(request, _('Smart link: %s deleted successfully.') % smart_link)
        except Exception as exception:
            messages.error(request, _('Error deleting smart link: %(smart_link)s; %(exception)s.') % {
                'smart_link': smart_link,
                'exception': exception
            })
        return HttpResponseRedirect(next)

    return render_to_response('appearance/generic_confirm.html', {
        'delete_view': True,
        'object': smart_link,
        'title': _('Are you sure you wish to delete smart link: %s?') % smart_link,
        'next': next,
        'previous': previous,
    }, context_instance=RequestContext(request))


def smart_link_condition_list(request, smart_link_pk):
    smart_link = get_object_or_404(SmartLink, pk=smart_link_pk)

    try:
        Permission.check_permissions(request.user, [permission_smart_link_edit])
    except PermissionDenied:
        AccessControlList.objects.check_access([permission_smart_link_edit], request.user, smart_link)

    return render_to_response('appearance/generic_list.html', {
        'title': _('Conditions for smart link: %s') % smart_link,
        'object_list': smart_link.conditions.all(),
        'extra_columns': [
            {'name': _('Enabled'), 'attribute': encapsulate(lambda x: two_state_template(x.enabled))},
        ],
        'hide_link': True,
        'object': smart_link,
    }, context_instance=RequestContext(request))


def smart_link_condition_create(request, smart_link_pk):
    smart_link = get_object_or_404(SmartLink, pk=smart_link_pk)

    try:
        Permission.check_permissions(request.user, [permission_smart_link_edit])
    except PermissionDenied:
        AccessControlList.objects.check_access([permission_smart_link_edit], request.user, smart_link)

    if request.method == 'POST':
        form = SmartLinkConditionForm(data=request.POST)
        if form.is_valid():
            new_smart_link_condition = form.save(commit=False)
            new_smart_link_condition.smart_link = smart_link
            new_smart_link_condition.save()
            messages.success(request, _('Smart link condition: "%s" created successfully.') % new_smart_link_condition)
            return HttpResponseRedirect(reverse('linking:smart_link_condition_list', args=[smart_link.pk]))
    else:
        form = SmartLinkConditionForm()

    return render_to_response('appearance/generic_form.html', {
        'form': form,
        'title': _('Add new conditions to smart link: "%s"') % smart_link,
        'object': smart_link,
    }, context_instance=RequestContext(request))


def smart_link_condition_edit(request, smart_link_condition_pk):
    smart_link_condition = get_object_or_404(SmartLinkCondition, pk=smart_link_condition_pk)

    try:
        Permission.check_permissions(request.user, [permission_smart_link_edit])
    except PermissionDenied:
        AccessControlList.objects.check_access([permission_smart_link_edit], request.user, smart_link_condition.smart_link)

    next = request.POST.get('next', request.GET.get('next', request.META.get('HTTP_REFERER', reverse(settings.LOGIN_REDIRECT_URL))))
    previous = request.POST.get('previous', request.GET.get('previous', request.META.get('HTTP_REFERER', reverse(settings.LOGIN_REDIRECT_URL))))

    if request.method == 'POST':
        form = SmartLinkConditionForm(request.POST, instance=smart_link_condition)
        if form.is_valid():
            smart_link_condition = form.save()
            messages.success(request, _('Smart link condition: "%s" edited successfully.') % smart_link_condition)
            return HttpResponseRedirect(next)
    else:
        form = SmartLinkConditionForm(instance=smart_link_condition)

    return render_to_response('appearance/generic_form.html', {
        'condition': smart_link_condition,
        'form': form,
        'navigation_object_list': ['object', 'condition'],
        'next': next,
        'object': smart_link_condition.smart_link,
        'previous': previous,
        'title': _('Edit smart link condition'),
    }, context_instance=RequestContext(request))


def smart_link_condition_delete(request, smart_link_condition_pk):
    smart_link_condition = get_object_or_404(SmartLinkCondition, pk=smart_link_condition_pk)

    try:
        Permission.check_permissions(request.user, [permission_smart_link_edit])
    except PermissionDenied:
        AccessControlList.objects.check_access([permission_smart_link_edit], request.user, smart_link_condition.smart_link)

    next = request.POST.get('next', request.GET.get('next', request.META.get('HTTP_REFERER', reverse(settings.LOGIN_REDIRECT_URL))))
    previous = request.POST.get('previous', request.GET.get('previous', request.META.get('HTTP_REFERER', reverse(settings.LOGIN_REDIRECT_URL))))

    if request.method == 'POST':
        try:
            smart_link_condition.delete()
            messages.success(request, _('Smart link condition: "%s" deleted successfully.') % smart_link_condition)
        except Exception as exception:
            messages.error(request, _('Error deleting smart link condition: %(smart_link_condition)s; %(exception)s.') % {
                'smart_link_condition': smart_link_condition,
                'exception': exception
            })
        return HttpResponseRedirect(next)

    return render_to_response('appearance/generic_confirm.html', {
        'condition': smart_link_condition,
        'delete_view': True,
        'navigation_object_list': ['object', 'condition'],
        'next': next,
        'object': smart_link_condition.smart_link,
        'previous': previous,
        'title': _('Are you sure you wish to delete smart link condition: "%s"?') % smart_link_condition,
    }, context_instance=RequestContext(request))