# -*- coding: utf-8 -*-

# File upload related imports
import os
from django.core.files.storage import default_storage
from django.core.files.base import ContentFile
from django.conf import settings

from django.views.generic import TemplateView, FormView, CreateView, UpdateView
from django.views.generic.detail import SingleObjectMixin
from django.contrib.auth.decorators import login_required
from django.utils.decorators import method_decorator
from django.contrib.auth.views import login, logout

from django.core.urlresolvers import reverse

from frontend.forms import NewProjectForm, FileUploadForm, PersonMapForm

from frontend.models import Project

FRONTEND_PAGE_NAME = u'Citavi Mapper'

from service.Mapper import person_mapper


# Login wrapper functions
def login_wrap(*args, **kwargs):
    """ Wrapper function for login page. """
    kwargs[u'extra_context'] = {
        u'page': {
            u'name': FRONTEND_PAGE_NAME,
            u'title': 'Login'
        }
    }
    return login(*args, **kwargs)

def logout_wrap(*args, **kwargs):
    """ Wrapper function for logout page. """
    kwargs[u'extra_context'] = {
        u'page': {
            u'name': FRONTEND_PAGE_NAME,
            u'title': 'Logout'
        }
    }
    return logout(*args, **kwargs)


# My base classes for views
class MyViewMixin(object):
    """ Basic view mixin to add global variables to all templates. """
    template_name = u'base.html'
    page_name = FRONTEND_PAGE_NAME
    page_title = u'BASE'

    def get_page_data(self):
        return {
            u'name': self.page_name,
            u'title': self.page_title
        }

    def get_context_data(self, **kwargs):
        kwargs[u'page'] = self.get_page_data()
        return super(MyViewMixin, self).get_context_data(**kwargs)

class MyTemplateView(MyViewMixin, TemplateView):
    pass

class MyFormView(MyViewMixin, FormView):
    pass

class MyCreateView(MyViewMixin, CreateView):
    pass

class MyUpdateView(MyViewMixin, UpdateView):
    pass


# Mixin to protect pages
class LoggedInMixin(object):
    """ Mixin to force a valid login for protected pages. """
    @method_decorator(login_required)
    def dispatch(self, *args, **kwargs):
        return super(LoggedInMixin, self).dispatch(*args, **kwargs)


# My protected view classes
class ProtectedTemplateView(LoggedInMixin, MyTemplateView):
    pass

class ProtectedFormView(LoggedInMixin, MyFormView):
    pass

class ProtectedCreateView(LoggedInMixin, MyCreateView):
    pass

class ProtectedUpdateView(LoggedInMixin, MyUpdateView):
    pass


# Actual Views
class IndexView(ProtectedTemplateView):
    template_name = u'index.html'
    page_title = u'Index'


class ProjectView(ProtectedFormView):
    template_name = u'projects.html'
    page_title = u'Projects'
    form_class = NewProjectForm
    success_url = u'/project'

    def get_context_data(self, **kwargs):
        kwargs[u'projects'] = Project.objects.order_by(u'id')
        return super(ProjectView, self).get_context_data(**kwargs)

    def form_valid(self, form):
        form.save()
        return super(ProjectView, self).form_valid(form)


class ProjectUpdateView(ProtectedFormView, SingleObjectMixin):
    template_name = u'project/update.html'
    page_title = u'Update project'
    form_class = FileUploadForm

    success_url = u'/project/'

    def get(self, request, *args, **kwargs):
        self.project_id = kwargs[u'project_id']
        self.object = Project.objects.get(pk=self.project_id)
        return super(ProjectUpdateView, self).get(request, *args, **kwargs)

    def post(self, request, *args, **kwargs):
        self.project_id = kwargs[u'project_id']
        self.object = Project.objects.get(pk=self.project_id)
        self.success_url = self.success_url + self.project_id + u'/update'
        return super(ProjectUpdateView, self).post(request, *args, **kwargs)

    def form_valid(self, form, *args, **kwargs):
        """ This form_valid handles the file upload. """
        original_file = form.files[u'file']
        original_filename = unicode(original_file)
        original_contentfile = ContentFile(original_file.read())
        """ Put file into temporary folder for analysis """
        target_filename = u'tmp/project_' + unicode(self.project_id) + u'.ctt4'
        relative_path = default_storage.save(target_filename, original_contentfile)
        temp_sqlite = os.path.join(settings.MEDIA_ROOT, relative_path)

        """ Test if SQLite is a valid citavi project. """
        from service import Citavi
        citavi_project = Citavi.Project(temp_sqlite)
        citavi_project.open()
        citavi_project_valid = citavi_project.is_valid()
        """ Free temporary ressources. """
        del citavi_project
        default_storage.delete(temp_sqlite)

        if citavi_project_valid == False:
            """ TODO: Put up an error message or something. """
            pass
        else:
            target_filename = u'citavi/project_' + unicode(self.project_id) + u'.ctt4'
            """ Remove eventually pre-existing citavi file. """
            if default_storage.exists(target_filename):
                default_storage.delete(target_filename)

            """ Actually store file in citavi folder """
            relative_path = default_storage.save(target_filename, original_contentfile)
            sqlite_path = os.path.join(settings.MEDIA_ROOT, relative_path)

            """ Store new original filename in Project """
            project = Project.objects.get(id=self.project_id)
            project.associated_filename = original_filename
            project.save()

            """ Refresh identities from citavi project. """
            # TODO
            # citavi_project = Citavi.Project(sqlite_path)
            # citavi_project.open()
            # del citavi_project
        return super(ProjectUpdateView, self).form_valid(form)


class ProjectPersonView(ProtectedFormView, SingleObjectMixin):
    template_name = u'project/view-person.html'
    page_title = u'Person List View'
    form_class = FileUploadForm

    success_url = u'/project/'

    def get_context_data(self, **kwargs):
        project = self.object
        kwargs[u'unmapped_persons'] = person_mapper.get_unmapped_identities(project)
        kwargs[u'mapped_persons'] = person_mapper.get_mapped_identities(project)
        return super(ProjectPersonView, self).get_context_data(**kwargs)

    def get(self, request, *args, **kwargs):
        self.project_id = kwargs[u'project_id']
        self.object = Project.objects.get(pk=self.project_id)
        return super(ProjectPersonView, self).get(request, *args, **kwargs)

    def post(self, request, *args, **kwargs):
        self.project_id = kwargs[u'project_id']
        # self.success_url = self.success_url + self.project_id + '/update'
        return super(ProjectPersonView, self).post(request, *args, **kwargs)

    def form_valid(self, form, *args, **kwargs):
        return super(ProjectPersonView, self).form_valid(form)


class ProjectMapPersonView(ProtectedFormView, SingleObjectMixin):
    """ View containing the person mapping 'wizard'. """
    template_name = u'project/map-person.html'
    page_title = u'Person Mapping'
    form_class = PersonMapForm

    success_url = u'/project'

    _unmapped_persons = None

    def _refresh_unmapped(self):
        """ Refresh data about unmapped persons. """
        self._unmapped_persons = person_mapper.get_unmapped_identities(self.object)

    def _is_unmapped(self, person_uuid):
        """ Returns True if the given person is not mapped yet. """
        if not self._unmapped_persons:
            self._refresh_unmapped()
        return person_uuid in self._unmapped_persons

    def get_context_data(self, **kwargs):
        project = self.object
        kwargs[u'person'] = person_mapper.get_person_by_uuid(project, self.person_uuid)
        return super(ProjectMapPersonView, self).get_context_data(**kwargs)

    def get_success_url(self):
        """ TODO: Make this work! - Update success uri to next unmapped person. """
        last_uuid = unicode(self.person_uuid)
        self._refresh_unmapped()
        unmapped = self._unmapped_persons.items()
        first_person_uuid = unmapped[0][0]
        next_uuid = first_person_uuid
        unmapped.reverse()

        while True:
            try:
                current_person = unmapped.pop()
                if current_person[1].ID == last_uuid:
                    next_uuid = unmapped.pop()[0]
                    break
            except IndexError:
                break

        kwargs = {
            u"project_id": self.object.id,
            u"person_uuid": next_uuid
        }
        return reverse('frontend-project-map-person', kwargs=kwargs)

    def get(self, request, *args, **kwargs):
        self.project_id = kwargs[u'project_id']
        self.person_uuid = kwargs[u'person_uuid']
        self.object = Project.objects.get(pk=self.project_id)
        if self._is_unmapped(self.person_uuid) == False:
            raise Exception("Sorry, this person was already mapped. Try deleting the existing mapping and move on. TODO: Make this more beautiful.")
        self._refresh_unmapped()
        return super(ProjectMapPersonView, self).get(request, *args, **kwargs)

    def post(self, request, *args, **kwargs):
        self.project_id = kwargs[u'project_id']
        self.person_uuid = kwargs[u'person_uuid']
        self.object = Project.objects.get(pk=self.project_id)
        if self._is_unmapped(self.person_uuid) == False:
            raise Exception("Sorry, this person was already mapped. Try deleting the existing mapping and move on. TODO: Make this more beautiful.")
        self._refresh_unmapped()
        return super(ProjectMapPersonView, self).post(request, *args, **kwargs)

    def form_valid(self, form, *args, **kwargs):
        person = person_mapper.get_person_by_uuid(self.object, self.person_uuid)

        if form.data.get(u'skip', False):
            """ Nothing to do here, just go on ... """
            pass
        elif form.data.get(u'save-continue', False):
            # TODO: do mapping according to parameters, override success_url to point to next person!
            if form.cleaned_data[u'action'] == u'new':
                person_mapper.create_new_identity(self.object, person)
            elif form.cleaned_data[u'action'] == u'existing':
                global_identity = form.cleaned_data[u'global_identity']
                person_mapper.map_identity_to_existing(global_identity, self.object, person.ID, form.cleaned_data[u'preferred_identity'])
        return super(ProjectMapPersonView, self).form_valid(form)