"""

"""


from django.shortcuts import get_object_or_404, redirect, resolve_url
from django.views.generic import RedirectView
from django.views.generic.detail import DetailView, SingleObjectMixin
from django.views.generic.list import ListView
from django.views.generic.edit import CreateView, UpdateView, FormMixin
from django.core.exceptions import SuspiciousOperation
from django.http import Http404, HttpResponseRedirect
from django.db.models import Q
from django.utils import timezone

from markdown2 import markdown

from . import models, forms
from interface.utils import check_signed_url

import logging
logger = logging.getLogger(__name__)

class AuthorizedResourceMixin(object):
    """
    Handles these parts of the permission system:
        * signed urls
        * persistent authenticated resources
        * Admin enforcing
    """

    SESSION_KEY = 'authorized'
    admin_required = False

    def is_authorized(self):
        "By default check if superuser or a signed request"
        if self.request.is_admin:
            #logger.debug("is_authorized: superuser")
            return True
        
        if 'sig' in self.request.GET:
            check_signed_url(self.request.get_full_path())
            self.on_signed_request()
            return True

        return False
    
    def on_signed_request(self):
        pass

    def is_authorized_key(self, resource, key, auth):
        current = self.get_authorized_keys(resource).get(str(key), None)
        if current is None:
            #logger.debug("is_authorized_key: %s %s not in session", resource, key)
            return False
        if auth == current:
            return True

        #logger.info("Authorisation revoked")
        self.del_authorized_key(resource, key)
        return False

    def get_authorized_keys(self, resource):
        'Returns a set of authorized keys for this resource'
        return self._authorized.get(resource, {})
    
    def add_authorized_key(self, resource, key, auth):
        'Adds a key to the authorized list for this resource'
        current = self.get_authorized_keys(resource)
        current[str(key)] = auth
        self._authorized[resource] = current
        self.request.session[self.SESSION_KEY] = self._authorized

    def del_authorized_key(self, resource, key):
        logger.info("Revoking authorization for %s %s", resource, key)
        current = self.get_authorized_keys(resource)
        if current.pop(key, None) is None:
            return False
        if current:
            self._authorized[resource] = current
        else:
            self._authorized.pop(resource)
        self.request.session[self.SESSION_KEY] = self._authorized
        return True

    def request_denied(self):
        raise Http404("Either the given resource doesn't exist or you dont have access to it.")

    def dispatch(self, request, *args, **kwargs):

        self._authorized = request.session.get('authorized', {})
        request.is_admin = request.user.is_superuser

        if not self.is_authorized():
            return self.request_denied()
        
        if self.admin_required and not request.is_admin:
            return self.request_denied()

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

# TODO: RevokeResourceView - increment nonce

class ForgetResourceView(AuthorizedResourceMixin, RedirectView):
    
    def is_authorized(self):
        return True

    def get_redirect_url(self, resource, key):
        self.del_authorized_key(resource, key)
        return "/" 

class EnsembleMixin(AuthorizedResourceMixin):

    ensemble_slug_kwarg = 'ensemble'
    limited_project_access = False

    def is_authorized(self):
        ensemble_slug = self.kwargs[self.ensemble_slug_kwarg]
        self.ensemble = get_object_or_404(models.Ensemble, slug=ensemble_slug)

        if super().is_authorized():
            return True
        
        if self.ensemble.has_admin(self.request.user):
            self.request.is_admin = True
            return True

        if self.is_authorized_key('ensemble', ensemble_slug, self.ensemble.nonce):
            return True
        
        authorized = set([ int(x) for x in self.get_authorized_keys('project').keys() ])
        projects = set(self.ensemble.projects.values_list('pk', flat=True))
        logger.debug("is_authorized: %r & %r", authorized, projects)
        if authorized & projects:
            self.limited_project_access = True
            logger.debug("is_authorized: allowing due to project link")
            return True
        return False

    def get_object(self):
        return self.ensemble


class ProjectMixin(AuthorizedResourceMixin):

    project_kwarg = 'project'

    def is_authorized(self):
        project_id = self.kwargs[self.project_kwarg]
        self.project = get_object_or_404(models.Project.objects.select_related('ensemble'), pk=project_id)

        if super().is_authorized():
            return True
        
        
        # check if the current user is an admin on the ensemble
        if self.project.ensemble.has_admin(self.request.user):
            logger.debug("is_authorized: ensemble admin for project")
            self.request.is_admin = True
            return True
        
        if self.is_authorized_key('ensemble', self.project.ensemble.pk, self.project.ensemble.nonce):
            logger.debug('is_authorized: has ensemble link for project')
            return True

        if self.is_authorized_key('project', project_id, self.project.nonce):
            logger.debug('is_authorized: has project link')
            return True

        return False

    # filter any generated querysets
    def get_queryset(self):
        return super().get_queryset().filter(project=self.project)

    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        if 'project' in self.kwargs:
            context['project'] = self.project
            context['modules'] = self.project.active_modules
        return context

class CrispyFormMixin(object):

    cancel_url = None

    def get_cancel_url(self):
        return self.cancel_url

""" ENSEMBLE VIEWS """

class EnsembleListView(AuthorizedResourceMixin, ListView):

    def is_authorized(self):
        return True
    
    def get_queryset(self):
        return models.Ensemble.objects.for_user(self.request.user,
                                                self.get_authorized_keys('ensemble').keys(),
                                                self.get_authorized_keys('project').keys())
        #ensembles = models.Ensemble.objects.all()

        #if self.request.is_admin:
        #    return ensembles

        # limit to registered ensembles
        #f = Q(slug__in=self.get_authorized_keys('ensemble').keys()) | Q(projects__in=self.get_authorized_keys('project').keys())
        
        # or ensembles where the user is admin
        #if self.request.user.is_authenticated:
        #    f |= Q(admins=self.request.user.pk)

        #return ensembles.filter(f).distinct()

class EnsembleDetailView(EnsembleMixin, DetailView):

    def request_denied(self):
        if 'auth' in self.request.GET:
            if self.request.GET['auth'] != self.ensemble.auth():
                raise SuspiciousOperation("Bad ensemble link")    
            self.add_authorized_key('ensemble', self.ensemble.slug, self.ensemble.nonce)
            return HttpResponseRedirect(resolve_url('ensemble_detail', self.ensemble.slug))
        
        return super().request_denied()
    
    def get_context_data(self, **kwargs):
        data = super().get_context_data(**kwargs)
        inactive = 'inactive' in self.request.GET and self.request.is_admin

        projects = self.ensemble.projects.all()
        if self.limited_project_access:
            projects = projects.filter(pk__in=self.get_authorized_keys('project').keys())

        if inactive:
            projects = projects.order_by('-pk')
        else:
            projects = projects.active().current()

        data['inactive'] = inactive
        data['object_list'] = projects
        if self.request.is_admin:
            data['ensemble_link'] = self.request.path + "?auth=" + self.ensemble.auth()
        return data

class EnsembleRevokeView(SingleObjectMixin, RedirectView):

    def get_redirect_url(self):
        return 

""" PROJECT VIEWS """

class ProjectListView(ProjectMixin, ListView):

    def is_authorized(self):
        return True
    
    def get_project_queryset(self):
        return models.Project.objects.for_user(self.request.user,
                                       self.get_authorized_keys('project'),
                                       self.get_authorized_keys('ensemble'))

    def get_queryset(self):
        return self.get_project_queryset().current().active()

class ProjectCreateView(EnsembleMixin, CreateView):
    admin_required = True
    model = models.Project
    template_name = "interface/default_form.html"
    title = "Add a new project"
    form_class = forms.ProjectForm


    def form_valid(self, form):
        self.object = form.save(commit=False)
        self.object.ensemble = self.ensemble
        self.object.owner = self.request.user
        self.object.save()

        for module in form.cleaned_data['modules']:
            self.object.modules.create(name=module)

        return redirect('project_detail', project=self.object.pk)

class ProjectDetailView(ProjectMixin, DetailView):

    def request_denied(self):
        if 'auth' in self.request.GET:
            if self.request.GET['auth'] != self.project.auth():
                raise SuspiciousOperation("Bad project link")
            self.add_authorized_key('project', self.project.pk, self.project.nonce)
            return HttpResponseRedirect(resolve_url('project_detail', self.project.pk))
        return super().request_denied()

    def get_object(self, queryset=None):
        return self.project

    def get_context_data(self, **kwargs):
        data = super().get_context_data(**kwargs)
        if self.request.is_admin:
            #data['project_link'] = signed_url(f'{self.request.path}?nonce={self.project.nonce}')
            data['project_link'] = self.request.path + "?auth=" + self.project.auth()
        return data

class ProjectUpdateView(ProjectMixin, UpdateView):
    admin_required = True
    template_name = "interface/default_form.html"
    pk_url_kwarg = 'project'
    form_class = forms.ProjectForm

    def get_object(self):
        return self.project

    def get_initial(self):
        data = super().get_initial()
        data['modules'] = self.object.active_modules
        print(data)
        return data
    
    def form_valid(self, form):
        self.object = form.save()
        current = set(self.object.active_modules)
        desired = set(form.cleaned_data['modules'])
        self.object.modules.exclude(name__in=desired).delete()
        for module in desired-current:
            self.object.modules.create(name=module)
        return redirect('project_detail', self.kwargs['project'])

    @property
    def cancel_url(self):
        return resolve_url('project_detail', self.kwargs['project'])


# Old Makefile from submission module
#class ProjectMakefileView(EnsembleMixin, DetailView):
#    template_name = 'interface/project_submissions.mk'
#    content_type = 'text/plain'
#
#    def get_queryset(self):
#        if self.request.is_admin:
#            return models.Project.objects.all()
#
#        return models.Project.objects.filter(ensemble=self.request.ensemble_id)
#
#    def get_context_data(self, **kwargs):
#        data = super().get_context_data(**kwargs)
#
#        data['submissions'] = []
#        data['targets'] = []
#        for s in self.object.submissions:
#            name = s.short_name
#            data['targets'].append(name)
#            data['submissions'].append({
#                'url': self.request.build_absolute_uri(signed_url('submission_download', project=self.kwargs['pk'], pk=s.pk)),
#                'name': name,
#            })
#
#        return data

""" WIKI VIEWS """

class WikiView(ProjectMixin, DetailView):
    template_name = 'interface/wiki.html'
    model = models.WikiPage

    def get_context_data(self, **kwargs):
        data = super().get_context_data(**kwargs)
        data['wiki_html'] = markdown(self.object.markdown)
        return data

class WikiCreateView(ProjectMixin, CreateView):
    admin_required = True
    model = models.WikiPage
    template_name = 'interface/default_form.html'
    form_class = forms.WikiForm

    def cancel_url(self):
        return resolve_url('project_detail', self.kwargs['project'])

    def form_valid(self, form):
        self.object = form.save(commit=False)
        self.object.project = self.project
        self.object.save()
        return redirect('wiki', project=self.object.project_id, pk=self.object.pk)

class WikiEditView(ProjectMixin, UpdateView):
    admin_required = True
    model = models.WikiPage
    form_class = forms.WikiForm

    def cancel_url(self):
        return resolve_url('wiki', self.kwargs['project'], self.kwargs['pk'])

""" RESOURCE VIEWS """

class ResourceCreateView(ProjectMixin, CreateView):
    admin_required = True
    model = models.Resource
    form_class = forms.ResourceForm
    template_name = 'interface/default_form.html'
    title = "Add a new resource"

    def form_valid(self, form):
        self.object = form.save(commit=False)
        self.object.project = self.project
        self.object.save()
        return redirect('resource_upload', project=self.object.project_id, pk=self.object.pk)

class ResourceUploadView(ProjectMixin, UpdateView):
    admin_required = True
    model = models.Resource
    fields = ['file']
    template_name = 'interface/default_form.html'

    def get_success_url(self):
        return resolve_url('resource_list', project=self.kwargs['project'])

class ResourceListView(ProjectMixin, ListView):
    model = models.Resource

    def get_queryset(self):
        qs = super().get_queryset()
        if not self.request.is_admin:
            qs = qs.filter(visible=True)
        return qs

class ResourceEditView(ProjectMixin, UpdateView):
    admin_required = True
    model = models.Resource
    fields = ['name', 'description', 'visible']
    template_name = 'interface/default_form.html'

    def get_success_url(self):
        return resolve_url('resource_list', project=self.kwargs['project'])