import structlog

from django.shortcuts import redirect
from django.views.generic import DetailView, ListView
from django.views.generic.edit import FormMixin

from .forms import LibraryForm
from .models import Category, Issue, Library, PullRequest

logger = structlog.get_logger()


class CategoryMixin:
    def get_context_data(self, **kwargs):
        context = super().get_context_data(**kwargs)
        context["categories"] = Category.objects.all().order_by("name")
        return context


class LibraryList(CategoryMixin, FormMixin, ListView):
    """List all of our libraries by name"""

    form_class = LibraryForm
    paginate_by = 25
    queryset = (
        Library.objects.prefetch_related("authors", "categories").all().order_by("name")
    )
    template_name = "libraries/list.html"

    def post(self, request):
        """User has submitted a form and will be redirected to the right results"""
        form = self.get_form()
        if form.is_valid():
            category = form.cleaned_data["categories"][0]
            return redirect("libraries-by-category", category=category.slug)
        else:
            logger.info("library_list_invalid_category")
        return super().get(request)


class LibraryByLetter(CategoryMixin, ListView):
    """List all of our libraries that begin with a certain letter"""

    paginate_by = 25
    template_name = "libraries/list.html"

    def get_queryset(self):
        letter = self.kwargs.get("letter")

        return (
            Library.objects.prefetch_related("categories")
            .filter(name__startswith=letter.lower())
            .order_by("name")
        )


class LibraryByCategory(CategoryMixin, ListView):
    """List all of our libraries in a certain category"""

    paginate_by = 25
    template_name = "libraries/list.html"

    def get_context_data(self, **kwargs):
        context = super().get_context_data()
        category_slug = self.kwargs.get("category")
        if category_slug:
            try:
                category = Category.objects.get(slug=category_slug)
                context["category"] = category
            except Category.DoesNotExist:
                logger.info("libraries_by_category_view_category_not_found")
        return context

    def get_queryset(self):
        category = self.kwargs.get("category")

        return (
            Library.objects.prefetch_related("categories")
            .filter(categories__slug=category)
            .order_by("name")
        )


class LibraryDetail(CategoryMixin, DetailView):
    """Display a single Library in insolation"""

    model = Library
    template_name = "libraries/detail.html"

    def get(self, request, *args, **kwargs):
        self.object = self.get_object()
        context = self.get_context_data(object=self.object)
        context["closed_prs_count"] = self.get_closed_prs_count(self.object)
        context["open_issues_count"] = self.get_open_issues_count(self.object)
        return self.render_to_response(context)

    def get_closed_prs_count(self, obj):
        return PullRequest.objects.filter(library=obj, is_open=True).count()

    def get_open_issues_count(self, obj):
        return Issue.objects.filter(library=obj, is_open=True).count()