# -*- coding: utf-8 -*-
from __future__ import unicode_literals

from django.db import models
from django.utils.translation import gettext_lazy as _

from filer.fields.file import FilerFileField
from filer.fields.image import FilerImageField
from filer.models import ThumbnailOption  # NOQA

from cms.models import CMSPlugin
from cms.models.fields import PageField
from cmsplugin_filer_utils import FilerPluginManager
from djangocms_attributes_field.fields import AttributesField

from .conf import settings


class FilerImage(CMSPlugin):
    LEFT = "left"
    RIGHT = "right"
    CENTER = "center"
    FLOAT_CHOICES = ((LEFT, _("left")),
                     (RIGHT, _("right")),
                     (CENTER, _("center")),
                     )
    STYLE_CHOICES = settings.CMSPLUGIN_FILER_IMAGE_STYLE_CHOICES
    DEFAULT_STYLE = settings.CMSPLUGIN_FILER_IMAGE_DEFAULT_STYLE
    EXCLUDED_KEYS = ['class', 'href', 'target', ]

    style = models.CharField(
        _('Style'), choices=STYLE_CHOICES, default=DEFAULT_STYLE, max_length=50, blank=True)
    caption_text = models.CharField(_("caption text"), null=True, blank=True, max_length=255)
    image = FilerImageField(
        null=True,
        blank=True,
        default=None,
        verbose_name=_("image"),
        on_delete=models.SET_NULL,
    )
    image_url = models.URLField(_("alternative image url"), null=True, blank=True, default=None)
    alt_text = models.CharField(_("alt text"), null=True, blank=True, max_length=255)
    use_original_image = models.BooleanField(
        _("use the original image"), default=False,
        help_text=_('do not resize the image. use the original image instead.'))
    thumbnail_option = models.ForeignKey(
        'filer.ThumbnailOption', null=True, blank=True, verbose_name=_("thumbnail option"),
        help_text=_('overrides width, height, crop and upscale with values from the selected thumbnail option'), on_delete=models.CASCADE)
    use_autoscale = models.BooleanField(_("use automatic scaling"), default=False,
                                        help_text=_('tries to auto scale the image based on the placeholder context'))
    width = models.PositiveIntegerField(_("width"), null=True, blank=True)
    height = models.PositiveIntegerField(_("height"), null=True, blank=True)
    crop = models.BooleanField(_("crop"), default=True)
    upscale = models.BooleanField(_("upscale"), default=True)
    alignment = models.CharField(_("image alignment"), max_length=10, blank=True, null=True, choices=FLOAT_CHOICES)

    free_link = models.CharField(_("link"), max_length=2000, blank=True, null=True,
                                 help_text=_("if present image will be clickable"))
    page_link = PageField(null=True, blank=True,
                          help_text=_("if present image will be clickable"),
                          verbose_name=_("page link"))
    file_link = FilerFileField(
        null=True,
        blank=True,
        default=None,
        verbose_name=_("file link"),
        help_text=_("if present image will be clickable"),
        related_name='+',
        on_delete=models.SET_NULL,
    )
    original_link = models.BooleanField(_("link original image"), default=False,
                                        help_text=_("if present image will be clickable"))
    description = models.TextField(_("description"), blank=True, null=True)
    target_blank = models.BooleanField(_('Open link in new window'), default=False)
    link_attributes = AttributesField(excluded_keys=EXCLUDED_KEYS, blank=True,
                                      help_text=_('Optional. Adds HTML attributes to the rendered link.'))
    cmsplugin_ptr = models.OneToOneField(
        to=CMSPlugin,
        related_name='%(app_label)s_%(class)s',
        parent_link=True,
     on_delete=models.CASCADE
    )

    # we only add the image to select_related. page_link and file_link are FKs
    # as well, but they are not used often enough to warrant the impact of two
    # additional LEFT OUTER JOINs.
    objects = FilerPluginManager(select_related=('image',))

    class Meta:
        verbose_name = _("filer image")
        verbose_name_plural = _("filer images")

    def clean(self):
        from django.core.exceptions import ValidationError
        # Make sure that either image or image_url is set
        if (not self.image and not self.image_url) or (self.image and self.image_url):
            raise ValidationError(_('Either an image or an image url must be selected.'))

    def __str__(self):
        if self.image:
            return self.image.label
        else:
            return _("Image Publication %(caption)s") % {'caption': self.caption or self.alt}
        return ''

    @property
    def caption(self):
        if self.image:
            return self.caption_text or self.image.default_caption
        else:
            return self.caption_text

    @property
    def alt(self):
        if self.image:
            return self.alt_text or self.image.default_alt_text or self.image.label
        else:
            return self.alt_text

    @property
    def link(self):
        if self.free_link:
            return self.free_link
        elif self.page_link:
            return self.page_link.get_absolute_url()
        elif self.file_link:
            return self.file_link.url
        elif self.original_link:
            if self.image:
                return self.image.url
            else:
                return self.image_url
        else:
            return ''