"""
Forms for the comments application.
"""
import datetime
from django import forms
from django.conf import settings
from django.contrib.contenttypes.models import ContentType

from comments.models import Comment
from core.html import ImageCheckError
from core.html import image_check
from core.markup import site_markup


COMMENT_MAX_LENGTH = getattr(settings, 'COMMENT_MAX_LENGTH', 3000)

class CommentForm(forms.Form):
    comment = forms.CharField(label='',
            min_length=1,
            max_length=COMMENT_MAX_LENGTH,
            widget=forms.Textarea(attrs={'class': 'markItUp smileyTarget'}))
    content_type = forms.CharField(widget=forms.HiddenInput)
    object_pk = forms.CharField(widget=forms.HiddenInput)

    def __init__(self, target_object, data=None, initial=None):
        self.target_object = target_object
        if initial is None:
            initial = {}
        initial.update({
            'content_type': str(self.target_object._meta),
            'object_pk': str(self.target_object.pk),
            })
        super(CommentForm, self).__init__(data=data, initial=initial)

    def get_comment_object(self, user, ip_address):
        """
        Return a new (unsaved) comment object based on the information in this
        form. Assumes that the form is already validated and will throw a
        ValueError if not.
        """
        if not self.is_valid():
            raise ValueError("get_comment_object may only be called on valid forms")

        new = Comment(
            content_type = ContentType.objects.get_for_model(self.target_object),
            object_id = self.target_object.pk,
            user = user,
            comment = self.cleaned_data["comment"],
            ip_address = ip_address,
            is_public = True,
            is_removed = False,
        )

        # Check that this comment isn't duplicate. (Sometimes people post comments
        # twice by mistake.) If it is, fail silently by returning the old comment.
        today = datetime.date.today()
        possible_duplicates = Comment.objects.filter(
            content_type = new.content_type,
            object_id = new.object_id,
            user = new.user,
            creation_date__year = today.year,
            creation_date__month = today.month,
            creation_date__day = today.day,
        )
        for old in possible_duplicates:
            if old.comment == new.comment:
                return old

        return new

    def clean_comment(self):
        comment = self.cleaned_data['comment']
        self.comment_html = None
        if comment:
            self.comment_html = site_markup(comment)
            try:
                image_check(self.comment_html)
            except ImageCheckError as ex:
                raise forms.ValidationError(str(ex))

        return comment