from django.conf import settings
from django.contrib.contenttypes.fields import GenericRelation
from django.db import models
from django.utils.translation import gettext as _
from modelcluster.fields import ParentalKey
from modelcluster.models import ClusterableModel
from wagtail.admin.panels import (
    FieldPanel,
    FieldRowPanel,
    InlinePanel,
    MultiFieldPanel,
    PublishingPanel,
)
from wagtail.contrib.forms.models import AbstractEmailForm, AbstractFormField
from wagtail.contrib.settings.models import (
    BaseGenericSetting,
    BaseSiteSetting,
    register_setting,
)
from wagtail.fields import RichTextField, StreamField
from wagtail.models import (
    Collection,
    DraftStateMixin,
    LockableMixin,
    Page,
    PreviewableMixin,
    RevisionMixin,
    Task,
    TaskState,
    TranslatableMixin,
    WorkflowMixin,
)
from wagtail.search import index

from .blocks import BaseStreamBlock


class Person(
    WorkflowMixin,
    DraftStateMixin,
    LockableMixin,
    RevisionMixin,
    PreviewableMixin,
    index.Indexed,
    ClusterableModel,
):
    """
    A Django model to store Person objects.
    It is registered using `register_snippet` as a function in wagtail_hooks.py
    to allow it to have a menu item within a custom menu item group.

    `Person` uses the `ClusterableModel`, which allows the relationship with
    another model to be stored locally to the 'parent' model (e.g. a PageModel)
    until the parent is explicitly saved. This allows the editor to use the
    'Preview' button, to preview the content, without saving the relationships
    to the database.
    https://github.com/wagtail/django-modelcluster
    """

    first_name = models.CharField("First name", max_length=254)
    last_name = models.CharField("Last name", max_length=254)
    job_title = models.CharField("Job title", max_length=254)

    image = models.ForeignKey(
        "wagtailimages.Image",
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="+",
    )

    workflow_states = GenericRelation(
        "wagtailcore.WorkflowState",
        content_type_field="base_content_type",
        object_id_field="object_id",
        related_query_name="person",
        for_concrete_model=False,
    )

    revisions = GenericRelation(
        "wagtailcore.Revision",
        content_type_field="base_content_type",
        object_id_field="object_id",
        related_query_name="person",
        for_concrete_model=False,
    )

    panels = [
        MultiFieldPanel(
            [
                FieldRowPanel(
                    [
                        FieldPanel("first_name"),
                        FieldPanel("last_name"),
                    ]
                )
            ],
            "Name",
        ),
        FieldPanel("job_title"),
        FieldPanel("image"),
        PublishingPanel(),
    ]

    search_fields = [
        index.SearchField("first_name"),
        index.SearchField("last_name"),
        index.FilterField("job_title"),
        index.AutocompleteField("first_name"),
        index.AutocompleteField("last_name"),
    ]

    @property
    def thumb_image(self):
        # Returns an empty string if there is no profile pic or the rendition
        # file can't be found.
        try:
            return self.image.get_rendition("fill-50x50").img_tag()
        except:  # noqa: E722 FIXME: remove bare 'except:'
            return ""

    @property
    def preview_modes(self):
        return PreviewableMixin.DEFAULT_PREVIEW_MODES + [("blog_post", _("Blog post"))]

    def __str__(self):
        return "{} {}".format(self.first_name, self.last_name)

    def get_preview_template(self, request, mode_name):
        from bakerydemo.blog.models import BlogPage

        if mode_name == "blog_post":
            return BlogPage.template
        return "base/preview/person.html"

    def get_preview_context(self, request, mode_name):
        from bakerydemo.blog.models import BlogPage

        context = super().get_preview_context(request, mode_name)
        if mode_name == self.default_preview_mode:
            return context

        page = BlogPage.objects.filter(blog_person_relationship__person=self).first()
        if page:
            # Use the page authored by this person if available,
            # and replace the instance from the database with the edited instance
            page.authors = [
                self if author.pk == self.pk else author for author in page.authors()
            ]
            # The authors() method only shows live authors, so make sure the instance
            # is included even if it's not live as this is just a preview
            if not self.live:
                page.authors.append(self)
        else:
            # Otherwise, get the first page and simulate the person as the author
            page = BlogPage.objects.first()
            page.authors = [self]

        context["page"] = page
        return context

    class Meta:
        verbose_name = "person"
        verbose_name_plural = "people"


class FooterText(
    DraftStateMixin,
    RevisionMixin,
    PreviewableMixin,
    TranslatableMixin,
    models.Model,
):
    """
    This provides editable text for the site footer. Again it is registered
    using `register_snippet` as a function in wagtail_hooks.py to be grouped
    together with the Person model inside the same main menu item. It is made
    accessible on the template via a template tag defined in base/templatetags/
    navigation_tags.py
    """

    body = RichTextField()

    revisions = GenericRelation(
        "wagtailcore.Revision",
        content_type_field="base_content_type",
        object_id_field="object_id",
        related_query_name="footer_text",
        for_concrete_model=False,
    )

    panels = [
        FieldPanel("body"),
        PublishingPanel(),
    ]

    def __str__(self):
        return "Footer text"

    def get_preview_template(self, request, mode_name):
        return "base.html"

    def get_preview_context(self, request, mode_name):
        return {"footer_text": self.body}

    class Meta(TranslatableMixin.Meta):
        verbose_name = "footer text"
        verbose_name_plural = "footer text"


class StandardPage(Page):
    """
    A generic content page. On this demo site we use it for an about page but
    it could be used for any type of page content that only needs a title,
    image, introduction and body field
    """

    introduction = models.TextField(help_text="Text to describe the page", blank=True)
    image = models.ForeignKey(
        "wagtailimages.Image",
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="+",
        help_text="Landscape mode only; horizontal width between 1000px and 3000px.",
    )
    body = StreamField(
        BaseStreamBlock(), verbose_name="Page body", blank=True, use_json_field=True
    )
    content_panels = Page.content_panels + [
        FieldPanel("introduction"),
        FieldPanel("body"),
        FieldPanel("image"),
    ]


class HomePage(Page):
    """
    The Home Page. This looks slightly more complicated than it is. You can
    see if you visit your site and edit the homepage that it is split between
    a:
    - Hero area
    - Body area
    - A promotional area
    - Moveable featured site sections
    """

    # Hero section of HomePage
    image = models.ForeignKey(
        "wagtailimages.Image",
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="+",
        help_text="Homepage image",
    )
    hero_text = models.CharField(
        max_length=255, help_text="Write an introduction for the bakery"
    )
    hero_cta = models.CharField(
        verbose_name="Hero CTA",
        max_length=255,
        help_text="Text to display on Call to Action",
    )
    hero_cta_link = models.ForeignKey(
        "wagtailcore.Page",
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="+",
        verbose_name="Hero CTA link",
        help_text="Choose a page to link to for the Call to Action",
    )

    # Body section of the HomePage
    body = StreamField(
        BaseStreamBlock(),
        verbose_name="Home content block",
        blank=True,
        use_json_field=True,
    )

    # Promo section of the HomePage
    promo_image = models.ForeignKey(
        "wagtailimages.Image",
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="+",
        help_text="Promo image",
    )
    promo_title = models.CharField(
        blank=True, max_length=255, help_text="Title to display above the promo copy"
    )
    promo_text = RichTextField(
        null=True, blank=True, max_length=1000, help_text="Write some promotional copy"
    )

    # Featured sections on the HomePage
    # You will see on templates/base/home_page.html that these are treated
    # in different ways, and displayed in different areas of the page.
    # Each list their children items that we access via the children function
    # that we define on the individual Page models e.g. BlogIndexPage
    featured_section_1_title = models.CharField(
        blank=True, max_length=255, help_text="Title to display above the promo copy"
    )
    featured_section_1 = models.ForeignKey(
        "wagtailcore.Page",
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="+",
        help_text="First featured section for the homepage. Will display up to "
        "three child items.",
        verbose_name="Featured section 1",
    )

    featured_section_2_title = models.CharField(
        blank=True, max_length=255, help_text="Title to display above the promo copy"
    )
    featured_section_2 = models.ForeignKey(
        "wagtailcore.Page",
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="+",
        help_text="Second featured section for the homepage. Will display up to "
        "three child items.",
        verbose_name="Featured section 2",
    )

    featured_section_3_title = models.CharField(
        blank=True, max_length=255, help_text="Title to display above the promo copy"
    )
    featured_section_3 = models.ForeignKey(
        "wagtailcore.Page",
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="+",
        help_text="Third featured section for the homepage. Will display up to "
        "six child items.",
        verbose_name="Featured section 3",
    )

    content_panels = Page.content_panels + [
        MultiFieldPanel(
            [
                FieldPanel("image"),
                FieldPanel("hero_text"),
                MultiFieldPanel(
                    [
                        FieldPanel("hero_cta"),
                        FieldPanel("hero_cta_link"),
                    ]
                ),
            ],
            heading="Hero section",
        ),
        MultiFieldPanel(
            [
                FieldPanel("promo_image"),
                FieldPanel("promo_title"),
                FieldPanel("promo_text"),
            ],
            heading="Promo section",
        ),
        FieldPanel("body"),
        MultiFieldPanel(
            [
                MultiFieldPanel(
                    [
                        FieldPanel("featured_section_1_title"),
                        FieldPanel("featured_section_1"),
                    ]
                ),
                MultiFieldPanel(
                    [
                        FieldPanel("featured_section_2_title"),
                        FieldPanel("featured_section_2"),
                    ]
                ),
                MultiFieldPanel(
                    [
                        FieldPanel("featured_section_3_title"),
                        FieldPanel("featured_section_3"),
                    ]
                ),
            ],
            heading="Featured homepage sections",
        ),
    ]

    def __str__(self):
        return self.title


class GalleryPage(Page):
    """
    This is a page to list locations from the selected Collection. We use a Q
    object to list any Collection created (/admin/collections/) even if they
    contain no items. In this demo we use it for a GalleryPage,
    and is intended to show the extensibility of this aspect of Wagtail
    """

    introduction = models.TextField(help_text="Text to describe the page", blank=True)
    image = models.ForeignKey(
        "wagtailimages.Image",
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="+",
        help_text="Landscape mode only; horizontal width between 1000px and " "3000px.",
    )
    body = StreamField(
        BaseStreamBlock(), verbose_name="Page body", blank=True, use_json_field=True
    )
    collection = models.ForeignKey(
        Collection,
        limit_choices_to=~models.Q(name__in=["Root"]),
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        help_text="Select the image collection for this gallery.",
    )

    content_panels = Page.content_panels + [
        FieldPanel("introduction"),
        FieldPanel("body"),
        FieldPanel("image"),
        FieldPanel("collection"),
    ]

    # Defining what content type can sit under the parent. Since it's a blank
    # array no subpage can be added
    subpage_types = []


class FormField(AbstractFormField):
    """
    Wagtailforms is a module to introduce simple forms on a Wagtail site. It
    isn't intended as a replacement to Django's form support but as a quick way
    to generate a general purpose data-collection form or contact form
    without having to write code. We use it on the site for a contact form. You
    can read more about Wagtail forms at:
    https://docs.wagtail.org/en/stable/reference/contrib/forms/index.html
    """

    page = ParentalKey("FormPage", related_name="form_fields", on_delete=models.CASCADE)


class FormPage(AbstractEmailForm):
    image = models.ForeignKey(
        "wagtailimages.Image",
        null=True,
        blank=True,
        on_delete=models.SET_NULL,
        related_name="+",
    )
    body = StreamField(BaseStreamBlock(), use_json_field=True)
    thank_you_text = RichTextField(blank=True)

    # Note how we include the FormField object via an InlinePanel using the
    # related_name value
    content_panels = AbstractEmailForm.content_panels + [
        FieldPanel("image"),
        FieldPanel("body"),
        InlinePanel("form_fields", heading="Form fields", label="Field"),
        FieldPanel("thank_you_text"),
        MultiFieldPanel(
            [
                FieldRowPanel(
                    [
                        FieldPanel("from_address"),
                        FieldPanel("to_address"),
                    ]
                ),
                FieldPanel("subject"),
            ],
            "Email",
        ),
    ]


@register_setting(icon="cog")
class GenericSettings(ClusterableModel, BaseGenericSetting):
    mastodon_url = models.URLField(verbose_name="Mastodon URL", blank=True)
    github_url = models.URLField(verbose_name="GitHub URL", blank=True)
    organisation_url = models.URLField(verbose_name="Organisation URL", blank=True)

    panels = [
        MultiFieldPanel(
            [
                FieldPanel("github_url"),
                FieldPanel("mastodon_url"),
                FieldPanel("organisation_url"),
            ],
            "Social settings",
        )
    ]


@register_setting(icon="site")
class SiteSettings(BaseSiteSetting):
    title_suffix = models.CharField(
        verbose_name="Title suffix",
        max_length=255,
        help_text="The suffix for the title meta tag e.g. ' | The Wagtail Bakery'",
        default="The Wagtail Bakery",
    )

    panels = [
        FieldPanel("title_suffix"),
    ]


class UserApprovalTaskState(TaskState):
    pass


class UserApprovalTask(Task):
    """
    Based on https://docs.wagtail.org/en/stable/extending/custom_tasks.html.
    """

    user = models.ForeignKey(
        settings.AUTH_USER_MODEL, on_delete=models.SET_NULL, null=True, blank=False
    )

    admin_form_fields = Task.admin_form_fields + ["user"]

    task_state_class = UserApprovalTaskState

    # prevent editing of `user` after the task is created
    # by default, this attribute contains the 'name' field to prevent tasks from being renamed
    admin_form_readonly_on_edit_fields = Task.admin_form_readonly_on_edit_fields + [
        "user"
    ]

    def user_can_access_editor(self, page, user):
        return user == self.user

    def page_locked_for_user(self, page, user):
        return user != self.user

    def get_actions(self, page, user):
        if user == self.user:
            return [
                ("approve", "Approve", False),
                ("reject", "Reject", False),
                ("cancel", "Cancel", False),
            ]
        else:
            return []

    def on_action(self, task_state, user, action_name, **kwargs):
        if action_name == "cancel":
            return task_state.workflow_state.cancel(user=user)
        else:
            return super().on_action(task_state, user, action_name, **kwargs)

    def get_task_states_user_can_moderate(self, user, **kwargs):
        if user == self.user:
            # get all task states linked to the (base class of) current task
            return TaskState.objects.filter(
                status=TaskState.STATUS_IN_PROGRESS, task=self.task_ptr
            )
        else:
            return TaskState.objects.none()

    @classmethod
    def get_description(cls):
        return _("Only a specific user can approve this task")