from datetime import datetime
import json

from django import forms
from django.contrib.admin.widgets import AdminDateWidget
from django.contrib.auth.models import User
from django.db.models import Q
from django.http import HttpResponse
from django.views.generic import ListView

from main.models import Package, Arch, Repo
from main.utils import make_choice
from ..models import PackageRelation
from ..utils import PackageJSONEncoder


def coerce_limit_value(value):
    if not value:
        return None
    if value == 'all':
        # negative value indicates show all results
        return -1
    value = int(value)
    if value < 0:
        raise ValueError
    return value

class LimitTypedChoiceField(forms.TypedChoiceField):
    def valid_value(self, value):
        try:
            coerce_limit_value(value)
            return True
        except (ValueError, TypeError):
            return False


class PackageSearchForm(forms.Form):
    repo = forms.MultipleChoiceField(required=False)
    arch = forms.MultipleChoiceField(required=False)
    name = forms.CharField(required=False)
    desc = forms.CharField(required=False)
    q = forms.CharField(required=False)
    sort = forms.CharField(required=False)
    maintainer = forms.ChoiceField(required=False)
    packager = forms.ChoiceField(required=False)
    last_update = forms.DateField(required=False, widget=AdminDateWidget(),
            label='Last Updated After')
    flagged = forms.ChoiceField(
            choices=[('', 'All')] + make_choice(['Flagged', 'Not Flagged']),
            required=False)
    limit = LimitTypedChoiceField(
            choices=make_choice([50, 100, 250]) + [('all', 'All')],
            coerce=coerce_limit_value,
            required=False,
            initial=50)

    def __init__(self, *args, **kwargs):
        super(PackageSearchForm, self).__init__(*args, **kwargs)
        self.fields['repo'].choices = make_choice(
                        [repo.name for repo in Repo.objects.all()])
        self.fields['arch'].choices = make_choice(
                        [arch.name for arch in Arch.objects.all()])
        self.fields['q'].widget.attrs.update({"size": "30"})
        maints = User.objects.filter(is_active=True).order_by(
                'first_name', 'last_name')
        self.fields['maintainer'].choices = \
                [('', 'All'), ('orphan', 'Orphan')] + \
                [(m.username, m.get_full_name()) for m in maints]
        self.fields['packager'].choices = \
                [('', 'All'), ('unknown', 'Unknown')] + \
                [(m.username, m.get_full_name()) for m in maints]


def parse_form(form, packages):
    if form.cleaned_data['repo']:
        packages = packages.filter(
                repo__name__in=form.cleaned_data['repo'])

    if form.cleaned_data['arch']:
        packages = packages.filter(
                arch__name__in=form.cleaned_data['arch'])

    if form.cleaned_data['maintainer'] == 'orphan':
        inner_q = PackageRelation.objects.all().values('pkgbase')
        packages = packages.exclude(pkgbase__in=inner_q)
    elif form.cleaned_data['maintainer']:
        inner_q = PackageRelation.objects.filter(
                user__username=form.cleaned_data['maintainer']).values('pkgbase')
        packages = packages.filter(pkgbase__in=inner_q)

    if form.cleaned_data['packager'] == 'unknown':
        packages = packages.filter(packager__isnull=True)
    elif form.cleaned_data['packager']:
        packages = packages.filter(
                packager__username=form.cleaned_data['packager'])

    if form.cleaned_data['flagged'] == 'Flagged':
        packages = packages.filter(flag_date__isnull=False)
    elif form.cleaned_data['flagged'] == 'Not Flagged':
        packages = packages.filter(flag_date__isnull=True)

    if form.cleaned_data['last_update']:
        lu = form.cleaned_data['last_update']
        packages = packages.filter(last_update__gte=
                datetime(lu.year, lu.month, lu.day, 0, 0))

    if form.cleaned_data['name']:
        name = form.cleaned_data['name']
        packages = packages.filter(pkgname=name)

    if form.cleaned_data['desc']:
        desc = form.cleaned_data['desc']
        packages = packages.filter(pkgdesc__icontains=desc)

    if form.cleaned_data['q']:
        query = form.cleaned_data['q']
        q = Q(pkgname__icontains=query) | Q(pkgdesc__icontains=query)
        packages = packages.filter(q)

    return packages


class SearchListView(ListView):
    template_name = "packages/search.html"

    sort_fields = ("arch", "repo", "pkgname", "pkgbase", "compressed_size",
            "installed_size", "build_date", "last_update", "flag_date")
    allowed_sort = list(sort_fields) + ["-" + s for s in sort_fields]

    def get(self, request, *args, **kwargs):
        self.form = PackageSearchForm(data=request.GET)
        return super(SearchListView, self).get(request, *args, **kwargs)

    def get_queryset(self):
        packages = Package.objects.normal()
        if self.form.is_valid():
            packages = parse_form(self.form, packages)
            sort = self.form.cleaned_data['sort']
            if sort in self.allowed_sort:
                packages = packages.order_by(sort)
            else:
                packages = packages.order_by('pkgname')
            return packages

        # Form had errors so don't return any results
        return Package.objects.none()

    def get_paginate_by(self, queryset):
        limit = 50
        if self.form.is_valid():
            asked_limit = self.form.cleaned_data['limit']
            if asked_limit and asked_limit < 0:
                limit = None
            elif asked_limit:
                limit = asked_limit
        return limit

    def get_context_data(self, **kwargs):
        context = super(SearchListView, self).get_context_data(**kwargs)
        context['current_query'] = self.request.GET.urlencode()
        context['search_form'] = self.form
        return context


def search_json(request):
    limit = 250

    container = {
        'version': 2,
        'limit': limit,
        'valid': False,
        'results': [],
    }

    if request.GET:
        form = PackageSearchForm(data=request.GET)
        if form.is_valid():
            packages = Package.objects.normal()
            packages = parse_form(form, packages)[:limit]
            container['results'] = packages
            container['valid'] = True

    to_json = json.dumps(container, ensure_ascii=False, cls=PackageJSONEncoder)
    return HttpResponse(to_json, mimetype='application/json')

# vim: set ts=4 sw=4 et: