/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at https://mozilla.org/MPL/2.0/. */

use crate::dom::attr::Attr;
use crate::dom::bindings::codegen::Bindings::HTMLOptGroupElementBinding::HTMLOptGroupElementMethods;
use crate::dom::bindings::inheritance::Castable;
use crate::dom::bindings::root::DomRoot;
use crate::dom::document::Document;
use crate::dom::element::{AttributeMutation, Element};
use crate::dom::htmlelement::HTMLElement;
use crate::dom::htmloptionelement::HTMLOptionElement;
use crate::dom::node::Node;
use crate::dom::virtualmethods::VirtualMethods;
use dom_struct::dom_struct;
use html5ever::{LocalName, Prefix};
use style::element_state::ElementState;

#[dom_struct]
pub struct HTMLOptGroupElement {
    htmlelement: HTMLElement,
}

impl HTMLOptGroupElement {
    fn new_inherited(
        local_name: LocalName,
        prefix: Option<Prefix>,
        document: &Document,
    ) -> HTMLOptGroupElement {
        HTMLOptGroupElement {
            htmlelement: HTMLElement::new_inherited_with_state(
                ElementState::IN_ENABLED_STATE,
                local_name,
                prefix,
                document,
            ),
        }
    }

    #[allow(unrooted_must_root)]
    pub fn new(
        local_name: LocalName,
        prefix: Option<Prefix>,
        document: &Document,
    ) -> DomRoot<HTMLOptGroupElement> {
        Node::reflect_node(
            Box::new(HTMLOptGroupElement::new_inherited(
                local_name, prefix, document,
            )),
            document,
        )
    }
}

impl HTMLOptGroupElementMethods for HTMLOptGroupElement {
    // https://html.spec.whatwg.org/multipage/#dom-optgroup-disabled
    make_bool_getter!(Disabled, "disabled");

    // https://html.spec.whatwg.org/multipage/#dom-optgroup-disabled
    make_bool_setter!(SetDisabled, "disabled");
}

impl VirtualMethods for HTMLOptGroupElement {
    fn super_type(&self) -> Option<&dyn VirtualMethods> {
        Some(self.upcast::<HTMLElement>() as &dyn VirtualMethods)
    }

    fn attribute_mutated(&self, attr: &Attr, mutation: AttributeMutation) {
        self.super_type().unwrap().attribute_mutated(attr, mutation);
        match attr.local_name() {
            &local_name!("disabled") => {
                let disabled_state = match mutation {
                    AttributeMutation::Set(None) => true,
                    AttributeMutation::Set(Some(_)) => {
                        // Option group was already disabled.
                        return;
                    },
                    AttributeMutation::Removed => false,
                };
                let el = self.upcast::<Element>();
                el.set_disabled_state(disabled_state);
                el.set_enabled_state(!disabled_state);
                let options = el
                    .upcast::<Node>()
                    .children()
                    .filter(|child| child.is::<HTMLOptionElement>())
                    .map(|child| DomRoot::from_ref(child.downcast::<HTMLOptionElement>().unwrap()));
                if disabled_state {
                    for option in options {
                        let el = option.upcast::<Element>();
                        el.set_disabled_state(true);
                        el.set_enabled_state(false);
                    }
                } else {
                    for option in options {
                        let el = option.upcast::<Element>();
                        el.check_disabled_attribute();
                    }
                }
            },
            _ => {},
        }
    }
}