# This file is part of FNP-Redakcja, licensed under GNU Affero GPLv3 or later.
# Copyright © Fundacja Nowoczesna Polska. See NOTICE for more information.
#
from django.db.models import Count
from django import forms
from django.utils.translation import gettext_lazy as _
from django.conf import settings
from slugify import slugify
from .constants import MASTERS
from .models import Book, Chunk, Image, User
from .docx import xml_from_docx

class DocumentCreateForm(forms.ModelForm):
    """
        Form used for creating new documents.
    """
    file = forms.FileField(required=False)
    text = forms.CharField(required=False, widget=forms.Textarea)
    docx = forms.FileField(required=False)

    class Meta:
        model = Book
        fields = [
            'title', 'slug', 'public', 'gallery'
        ]

    def __init__(self, *args, **kwargs):
        super(DocumentCreateForm, self).__init__(*args, **kwargs)
        self.fields['slug'].widget.attrs={'class': 'autoslug'}
        self.fields['slug'].required = False
        self.fields['gallery'].widget.attrs={'class': 'autoslug'}
        self.fields['title'].widget.attrs={'class': 'autoslug-source'}
        self.fields['title'].required = False

    def clean(self):
        super(DocumentCreateForm, self).clean()
        file = self.cleaned_data['file']

        if file is not None:
            try:
                self.cleaned_data['text'] = file.read().decode('utf-8')
            except UnicodeDecodeError:
                raise forms.ValidationError(_("Text file must be UTF-8 encoded."))

        docx = self.cleaned_data['docx']
        if docx is not None:
            try:
                text, meta = xml_from_docx(docx)
            except Exception as e:
                raise forms.ValidationError(e)
            else:
                self.cleaned_data['text'] = text
                if not self.cleaned_data['title']:
                    self.cleaned_data['title'] = meta.get('title', '')
                if not self.cleaned_data['slug']:
                    self.cleaned_data['slug'] = slugify(meta.get('title', ''))

        if not self.cleaned_data["title"]:
            self._errors["title"] = self.error_class([_("Title not set")])

        if not self.cleaned_data["slug"]:
            self._errors["slug"] = self.error_class([_("Slug not set")])

        if not self.cleaned_data["text"]:
            self._errors["text"] = self.error_class([_("You must either enter text or upload a file")])

        return self.cleaned_data


class DocumentsUploadForm(forms.Form):
    """
        Form used for uploading new documents.
    """
    file = forms.FileField(required=True, label=_('ZIP file'))
    dirs = forms.BooleanField(label=_('Directories are documents in chunks'),
            widget = forms.CheckboxInput(attrs={'disabled':'disabled'}))

    def clean(self):
        file = self.cleaned_data['file']

        import zipfile
        try:
            z = self.cleaned_data['zip'] = zipfile.ZipFile(file)
        except zipfile.BadZipfile:
            raise forms.ValidationError("Should be a ZIP file.")
        if z.testzip():
            raise forms.ValidationError("ZIP file corrupt.")

        return self.cleaned_data


class ChunkForm(forms.ModelForm):
    """
        Form used for editing a chunk.
    """
    user = forms.ModelChoiceField(queryset=
        User.objects.annotate(count=Count('chunk')).
        order_by('last_name', 'first_name'), required=False,
        label=_('Assigned to')) 

    class Meta:
        model = Chunk
        fields = ['title', 'slug', 'gallery_start', 'user', 'stage']
        exclude = ['number']

    def __init__(self, *args, **kwargs):
        super(ChunkForm, self).__init__(*args, **kwargs)
        self.fields['gallery_start'].widget.attrs={'class': 'number-input'}
        self.fields['slug'].widget.attrs={'class': 'autoslug'}
        self.fields['title'].widget.attrs={'class': 'autoslug-source'}

    def clean_slug(self):
        slug = self.cleaned_data['slug']
        try:
            chunk = Chunk.objects.get(book=self.instance.book, slug=slug)
        except Chunk.DoesNotExist:
            return slug
        if chunk == self.instance:
            return slug
        raise forms.ValidationError(_('Chunk with this slug already exists'))


class ChunkAddForm(ChunkForm):
    """
        Form used for adding a chunk to a document.
    """

    def clean_slug(self):
        slug = self.cleaned_data['slug']
        try:
            user = Chunk.objects.get(book=self.instance.book, slug=slug)
        except Chunk.DoesNotExist:
            return slug
        raise forms.ValidationError(_('Chunk with this slug already exists'))


class BookAppendForm(forms.Form):
    """
        Form for appending a book to another book.
        It means moving all chunks from book A to book B and deleting A.
    """
    append_to = forms.ModelChoiceField(queryset=Book.objects.all(),
            label=_("Append to"))

    def __init__(self, book, *args, **kwargs):
        ret =  super(BookAppendForm, self).__init__(*args, **kwargs)
        self.fields['append_to'].queryset = Book.objects.exclude(pk=book.pk)
        return ret


class BookForm(forms.ModelForm):
    """Form used for editing a Book."""

    class Meta:
        model = Book
        exclude = ['project', 'cover']

    def __init__(self, *args, **kwargs):
        ret = super(BookForm, self).__init__(*args, **kwargs)
        self.fields['slug'].widget.attrs.update({"class": "autoslug"})
        self.fields['title'].widget.attrs.update({"class": "autoslug-source"})
        return ret

    def save(self, **kwargs):
        orig_instance = Book.objects.get(pk=self.instance.pk)
        old_gallery = orig_instance.gallery
        new_gallery = self.cleaned_data['gallery']
        if new_gallery and old_gallery and new_gallery != old_gallery:
            import shutil
            import os.path
            from django.conf import settings
            shutil.move(orig_instance.gallery_path(),
                        os.path.join(settings.MEDIA_ROOT, settings.IMAGE_DIR, new_gallery))
        super(BookForm, self).save(**kwargs)


class ReadonlyBookForm(BookForm):
    """Form used for not editing a Book."""

    def __init__(self, *args, **kwargs):
        ret = super(ReadonlyBookForm, self).__init__(*args, **kwargs)
        for field in self.fields.values():
            field.widget.attrs.update({"disabled": "disabled"})
        return ret


class ChooseMasterForm(forms.Form):
    """
        Form used for fixing the chunks in a book.
    """

    master = forms.ChoiceField(choices=((m, m) for m in MASTERS))


class ImageForm(forms.ModelForm):
    """Form used for editing an Image."""
    user = forms.ModelChoiceField(queryset=
        User.objects.annotate(count=Count('chunk')).
        order_by('-count', 'last_name', 'first_name'), required=False,
        label=_('Assigned to')) 

    class Meta:
        model = Image
        fields = ['title', 'slug', 'user', 'stage']

    def __init__(self, *args, **kwargs):
        super(ImageForm, self).__init__(*args, **kwargs)
        self.fields['slug'].widget.attrs={'class': 'autoslug'}
        self.fields['title'].widget.attrs={'class': 'autoslug-source'}


class ReadonlyImageForm(ImageForm):
    """Form used for not editing an Image."""

    def __init__(self, *args, **kwargs):
        super(ReadonlyImageForm, self).__init__(*args, **kwargs)
        for field in self.fields.values():
            field.widget.attrs.update({"disabled": "disabled"})


class MarkFinalForm(forms.Form):
    username = forms.CharField(initial=settings.LITERARY_DIRECTOR_USERNAME)
    comment = forms.CharField(initial=u'Ostateczna akceptacja merytoryczna przez kierownika literackiego.')
    books = forms.CharField(widget=forms.Textarea, help_text=u'linki do książek w redakcji, po jednym na wiersz')

    def clean_books(self):
        books_value = self.cleaned_data['books']
        slugs = [line.strip().strip('/').split('/')[-1] for line in books_value.split('\n') if line.strip()]
        books = Book.objects.filter(slug__in=slugs)
        if len(books) != len(slugs):
            raise forms.ValidationError(
                'Incorrect slug(s): %s' % ' '.join(slug for slug in slugs if not Book.objects.filter(slug=slug)))
        return books

    def clean_username(self):
        username = self.cleaned_data['username']
        if not User.objects.filter(username=username):
            raise forms.ValidationError('Invalid username')
        return username

    def save(self):
        for book in self.cleaned_data['books']:
            for chunk in book.chunk_set.all():
                src = chunk.head.materialize()
                chunk.commit(
                    text=src,
                    author=User.objects.get(username=self.cleaned_data['username']),
                    description=self.cleaned_data['comment'],
                    tags=[Chunk.tag_model.objects.get(slug='editor-proofreading')],
                    publishable=True
                )


class PublishOptionsForm(forms.Form):
    days = forms.IntegerField(label=u'po ilu dniach udostępnienić (0 = od razu)', min_value=0, initial=0)
    hidden = forms.BooleanField(label='tekst ukryty przed wyszukiwaniem', required=False, initial=False)
    beta = forms.BooleanField(label=u'Opublikuj na wersji testowej', required=False)