from __future__ import absolute_import, unicode_literals

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 _, ungettext

from acls.models import AccessEntry
from common.views import ConfirmView
from documents.models import Document, DocumentVersion
from permissions.models import Permission

from .forms import DocumentContentForm
from .models import DocumentVersionOCRError
from .permissions import (
    PERMISSION_OCR_CONTENT_VIEW, PERMISSION_OCR_DOCUMENT,
    PERMISSION_OCR_DOCUMENT_DELETE
)


class DocumentSubmitView(ConfirmView):
    def get_context_data(self, **kwargs):
        context = super(DocumentSubmitView, self).get_context_data(**kwargs)

        context.update(
            {
                'title': _('Are you sure you wish to submit the selected document for OCR?')
            }
        )

        return context

    def object_action(self, request, obj):
        document = obj

        try:
            Permission.objects.check_permissions(request.user, [PERMISSION_OCR_DOCUMENT])
        except PermissionDenied:
            AccessEntry.objects.check_access(PERMISSION_OCR_DOCUMENT, request.user, document)

        document.submit_for_ocr()
        messages.success(request, _('Document: %(document)s was added to the OCR queue.') % {
            'document': document}
        )

    def post(self, request, *args, **kwargs):
        document = get_object_or_404(Document, pk=self.kwargs['pk'])
        self.object_action(request=request, obj=document)

        return HttpResponseRedirect(self.get_success_url())


class DocumentManySubmitView(DocumentSubmitView):
    def get_context_data(self, **kwargs):
        context = super(DocumentSubmitView, self).get_context_data(**kwargs)

        context.update(
            {
                'title': _('Are you sure you wish to submit the selected documents for OCR?')
            }
        )

        return context

    def post(self, request, *args, **kwargs):
        for pk in request.GET.get('id_list', '').split(','):
            document = get_object_or_404(Document, pk=pk)
            try:
                self.object_action(request=request, obj=document)
            except PermissionDenied:
                pass

        return HttpResponseRedirect(self.get_success_url())


def document_content(request, document_id):
    document = get_object_or_404(Document, pk=document_id)

    try:
        Permission.objects.check_permissions(request.user, [PERMISSION_OCR_CONTENT_VIEW])
    except PermissionDenied:
        AccessEntry.objects.check_access(PERMISSION_OCR_CONTENT_VIEW, request.user, document)

    document.add_as_recent_document_for_user(request.user)

    content_form = DocumentContentForm(document=document)

    return render_to_response('appearance/generic_form.html', {
        'document': document,
        'form': content_form,
        'hide_labels': True,
        'object': document,
        'read_only': True,
        'title': _('Content of document: %s') % document,
    }, context_instance=RequestContext(request))


def entry_list(request):
    Permission.objects.check_permissions(request.user, [PERMISSION_OCR_DOCUMENT])

    context = {
        'object_list': DocumentVersionOCRError.objects.all(),
        'title': _('OCR errors'),
        'hide_object': True,
    }

    return render_to_response('appearance/generic_list.html', context,
                              context_instance=RequestContext(request))


def entry_delete(request, pk=None, pk_list=None):
    Permission.objects.check_permissions(request.user, [PERMISSION_OCR_DOCUMENT_DELETE])

    if pk:
        entries = [get_object_or_404(DocumentVersionOCRError, pk=pk)]
    elif pk_list:
        entries = [get_object_or_404(DocumentVersionOCRError, pk=pk) for pk in pk_list.split(',')]
    else:
        messages.error(request, _('Make at least one selection.'))
        return HttpResponseRedirect(request.META.get('HTTP_REFERER', reverse(settings.LOGIN_REDIRECT_URL)))

    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':
        for entry in entries:
            try:
                entry.delete()
                messages.success(request, _('Entry: %(entry)s deleted successfully.') % {
                    'entry': entry})

            except Exception as exception:
                messages.error(request, _('Error entry: %(entry)s; %(error)s') % {
                    'entry': entry, 'error': exception})
        return HttpResponseRedirect(next)

    context = {
        'next': next,
        'previous': previous,
        'delete_view': True,
    }

    if len(entries) == 1:
        context['object'] = entries[0]

    context['title'] = ungettext(
        'Are you sure you wish to delete the selected entry?',
        'Are you sure you wish to delete the selected entries?',
        len(entries)
    )

    return render_to_response('appearance/generic_confirm.html', context,
                              context_instance=RequestContext(request))


def entry_delete_multiple(request):
    return entry_delete(request, pk_list=request.GET.get('id_list', ''))


def entry_re_queue(request, pk=None, pk_list=None):
    Permission.objects.check_permissions(request.user, [PERMISSION_OCR_DOCUMENT])

    if pk:
        entries = [get_object_or_404(DocumentVersionOCRError, pk=pk)]
    elif pk_list:
        entries = [get_object_or_404(DocumentVersionOCRError, pk=pk) for pk in pk_list.split(',')]
    else:
        messages.error(request, _('Make at least one selection.'))
        return HttpResponseRedirect(request.META.get('HTTP_REFERER', reverse(settings.LOGIN_REDIRECT_URL)))

    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':
        for entry in entries:
            try:
                entry.document_version.submit_for_ocr()
                messages.success(
                    request,
                    _('Entry: %(entry)s was re-queued for OCR.') % {
                        'entry': entry
                    }
                )
            except DocumentVersion.DoesNotExist:
                messages.error(request, _('Document version id#: %d, no longer exists.') % entry.document_version_id)
        return HttpResponseRedirect(next)

    context = {
        'next': next,
        'previous': previous,
    }

    if len(entries) == 1:
        context['object'] = entries[0]

    context['title'] = ungettext(
        'Are you sure you wish to re-queue the selected entry?',
        'Are you sure you wish to re-queue the selected entries?',
        len(entries)
    )

    return render_to_response('appearance/generic_confirm.html', context,
                              context_instance=RequestContext(request))


def entry_re_queue_multiple(request):
    return entry_re_queue(request, pk_list=request.GET.get('id_list', []))