"""
This file contains the forms used by the bio application.
"""
try:
    from cStringIO import StringIO
except:
    from StringIO import StringIO

from django import forms
from django.conf import settings
from django.core.files.base import ContentFile
from django.contrib.auth.models import User

import pytz

from bio.models import UserProfile
from core.html import image_check
from core.html import ImageCheckError
from core.images.utils import parse_image, downscale_image_square
from core.markup import site_markup
from core.widgets import AutoCompleteUserInput


class EditUserForm(forms.ModelForm):
    """Form for editing the fields of the User model."""
    email = forms.EmailField(label='Email', required=True)
    class Meta:
        model = User
        fields = ('first_name', 'last_name', 'email')


class EditUserProfileForm(forms.ModelForm):
    """Form for editing the fields of the UserProfile model."""
    location = forms.CharField(required=False, widget=forms.TextInput(attrs={'size': 64 }))
    occupation = forms.CharField(required=False, widget=forms.TextInput(attrs={'size': 64 }))
    interests = forms.CharField(required=False, widget=forms.TextInput(attrs={'size': 64 }))
    time_zone = forms.CharField(required=False, widget=forms.HiddenInput())
    use_24_time = forms.BooleanField(label='Show times in 24-hour mode', required=False)
    profile_text = forms.CharField(required=False,
        widget=forms.Textarea(attrs={'class': 'markItUp'}))
    signature = forms.CharField(required=False,
        widget=forms.Textarea(attrs={'class': 'markItUp'}))
    auto_favorite = forms.BooleanField(
        label='Automatically favorite every forum topic I create or reply to', required=False)
    auto_subscribe = forms.BooleanField(
        label='Automatically subscribe to every forum topic I create or reply to', required=False)

    class Meta:
        model = UserProfile
        fields = ('location', 'country', 'birthday', 'occupation', 'interests',
            'profile_text', 'hide_email', 'signature', 'time_zone',
            'use_24_time', 'auto_favorite', 'auto_subscribe')

    def clean_time_zone(self):
        """Ensure the timezone is valid and will work with pytz.

        A blank (empty) value is allowed.
        """

        tz = self.cleaned_data['time_zone'].strip()
        if tz:
            try:
                pytz.timezone(tz)
            except pytz.UnknownTimeZoneError:
                raise forms.ValidationError('Invalid timezone')

        return tz

    def _image_check(self, field_name):
        text = self.cleaned_data[field_name]
        if text:
            html = site_markup(text)
            try:
                image_check(html)
            except ImageCheckError as ex:
                raise forms.ValidationError(str(ex))
        return text

    def clean_profile_text(self):
        return self._image_check('profile_text')

    def clean_signature(self):
        return self._image_check('signature')


class UploadAvatarForm(forms.Form):
    """Form used to change a user's avatar"""
    avatar_file = forms.ImageField(required=False)
    image = None

    def clean_avatar_file(self):
        f = self.cleaned_data['avatar_file']
        if f is not None:
            if f.size > settings.MAX_AVATAR_SIZE_BYTES:
                raise forms.ValidationError("Please upload a file smaller than "
                    "%s bytes." % settings.MAX_AVATAR_SIZE_BYTES)
            try:
                self.image = parse_image(f)
            except IOError:
                raise forms.ValidationError("Please upload a valid image. "
                    "The file you uploaded was either not an image or a "
                    "corrupted image.")
            self.file_type = self.image.format
        return f

    def save(self):
        """
        Perform any down-scaling needed on the new file, then return a tuple of
        (filename, file object). Note that the file object returned may not
        have a name; use the returned filename instead.

        """
        if not self.cleaned_data['avatar_file']:
            return None, None

        name = self.cleaned_data['avatar_file'].name
        dim = settings.MAX_AVATAR_SIZE_PIXELS
        max_size = (dim, dim)
        if self.image and self.image.size > max_size:
            self.image = downscale_image_square(self.image, dim)

            # We need to return a Django File now. To get that from here,
            # write the image data info a StringIO and then construct a
            # Django ContentFile from that. The ContentFile has no name,
            # that is why we return one ourselves explicitly.
            s = StringIO()
            self.image.save(s, self.file_type)
            return name, ContentFile(s.getvalue())

        return name, self.cleaned_data['avatar_file']


class SearchUsersForm(forms.Form):
    """
    A form to search for users.
    """
    username = forms.CharField(max_length=30, widget=AutoCompleteUserInput())

    def clean_username(self):
      username = self.cleaned_data['username'].strip()
      try:
         User.objects.get(username=username, is_active=True)
      except User.DoesNotExist:
         raise forms.ValidationError("That username does not exist.")
      return username