import re
from django import forms
from django.forms.util import ErrorList
from boards.models import TITLE_MAX_LENGTH
from neboard import settings


class PlainErrorList(ErrorList):
    def __unicode__(self):
        return self.as_text()

    def as_text(self):
        return ''.join([u'(!) %s ' % e for e in self])


class PostForm(forms.Form):

    MAX_TEXT_LENGTH = 10000
    MAX_IMAGE_SIZE = 8 * 1024 * 1024

    title = forms.CharField(max_length=TITLE_MAX_LENGTH, required=False)
    text = forms.CharField(widget=forms.Textarea, required=False)
    image = forms.ImageField(required=False)

    def clean_title(self):
        title = self.cleaned_data['title']
        if title:
            if len(title) > TITLE_MAX_LENGTH:
                raise forms.ValidationError('Title must have less than' +
                                            str(TITLE_MAX_LENGTH) +
                                            ' characters.')
        return title

    def clean_text(self):
        text = self.cleaned_data['text']
        if text:
            if len(text) > self.MAX_TEXT_LENGTH:
                raise forms.ValidationError('Text must have less than ' +
                                            str(self.MAX_TEXT_LENGTH) +
                                            ' characters.')
        return text

    def clean_image(self):
        image = self.cleaned_data['image']
        if image:
            if image._size > self.MAX_IMAGE_SIZE:
                raise forms.ValidationError('Image must be less than ' +
                                            str(self.MAX_IMAGE_SIZE) +
                                            ' bytes.')
        return image

    def clean(self):
        cleaned_data = super(PostForm, self).clean()

        self._clean_text_image()

        return cleaned_data

    def _clean_text_image(self):
        text = self.cleaned_data.get('text')
        image = self.cleaned_data.get('image')

        if (not text) and (not image):
            error_message = 'Either text or image must be entered.'
            self._errors['text'] = self.error_class([error_message])
            self._errors['image'] = self.error_class([error_message])


class ThreadForm(PostForm):
    regex_tags = re.compile(ur'^[\w\s\d]+$', re.UNICODE)
    tags = forms.CharField(max_length=100)

    def clean_tags(self):
        tags = self.cleaned_data['tags']

        if tags:
            if not self.regex_tags.match(tags):
                raise forms.ValidationError(
                    'Inappropriate characters in tags.')

        return tags

    def clean(self):
        cleaned_data = super(ThreadForm, self).clean()

        return cleaned_data


class SettingsForm(forms.Form):
    theme = forms.ChoiceField(choices=settings.THEMES, widget=forms.RadioSelect)