from django.shortcuts import render
from django.contrib.auth.decorators import login_required
from books.models import Book
from common.models import MarkStatusEnum
from common.utils import PageLinksGenerator
from users.models import Report, User
from django.core.paginator import Paginator
from django.db.models import Q, Count
from django.http import HttpResponseBadRequest


# how many books have in each set at the home page
BOOKS_PER_SET = 5

# how many items are showed in one search result page
ITEMS_PER_PAGE = 20

# how many pages links in the pagination
PAGE_LINK_NUMBER = 7

# max tags on list page
TAG_NUMBER_ON_LIST = 5


@login_required
def home(request):
    if request.method == 'GET':

        do_book_marks = request.user.user_bookmarks.filter(status=MarkStatusEnum.DO)
        do_books_more = True if do_book_marks.count() > BOOKS_PER_SET else False

        wish_book_marks = request.user.user_bookmarks.filter(status=MarkStatusEnum.WISH)
        wish_books_more = True if wish_book_marks.count() > BOOKS_PER_SET else False
        
        collect_book_marks = request.user.user_bookmarks.filter(status=MarkStatusEnum.COLLECT)
        collect_books_more = True if collect_book_marks.count() > BOOKS_PER_SET else False

        reports = Report.objects.order_by('-submitted_time').filter(is_read=False)
        # reports = Report.objects.latest('submitted_time').filter(is_read=False)

        return render(
            request,
            'common/home.html',
            {
                'do_book_marks': do_book_marks[:BOOKS_PER_SET],
                'wish_book_marks': wish_book_marks[:BOOKS_PER_SET],
                'collect_book_marks': collect_book_marks[:BOOKS_PER_SET],
                'do_books_more': do_books_more,
                'wish_books_more': wish_books_more,
                'collect_books_more': collect_books_more,
                'reports': reports,
            }
        )
    else:
        return HttpResponseBadRequest()


@login_required
def search(request):
    if request.method == 'GET':
        # in the future when more modules are added...
        # category = request.GET.get("category")
        q = Q()
        query_args = []

        # keywords
        keywords = request.GET.get("q", default='').split()
        for keyword in keywords:
            q = q | Q(title__icontains=keyword)
            q = q | Q(subtitle__istartswith=keyword)
            q = q | Q(orig_title__icontains=keyword)

        # tag
        tag = request.GET.get("tag", default='')
        if tag:
            q = q | Q(book_tags__content__iexact=tag)

        query_args.append(q)
        queryset = Book.objects.filter(*query_args).distinct()

        paginator = Paginator(queryset, ITEMS_PER_PAGE)
        page_number = request.GET.get('page', default=1)
        items = paginator.get_page(page_number)
        items.pagination = PageLinksGenerator(PAGE_LINK_NUMBER, page_number, paginator.num_pages)
        for item in items:
            item.tag_list = item.get_tags_manager().values('content').annotate(
                tag_frequency=Count('content')).order_by('-tag_frequency')[:TAG_NUMBER_ON_LIST]

        return render(
            request,
            "common/search_result.html",
            {
                "items": items,
            }
        )

    else:
        return HttpResponseBadRequest()