servo/components/script/dom/svg/svgelement.rs

/* 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 dom_struct::dom_struct;
use html5ever::{LocalName, Prefix, local_name, ns};
use js::rust::HandleObject;
use script_bindings::codegen::GenericBindings::ElementBinding::ScrollLogicalPosition;
use script_bindings::codegen::GenericBindings::WindowBinding::ScrollBehavior;
use script_bindings::str::DOMString;
use stylo_dom::ElementState;

use crate::dom::attr::Attr;
use crate::dom::bindings::codegen::Bindings::HTMLOrSVGElementBinding::FocusOptions;
use crate::dom::bindings::codegen::Bindings::SVGElementBinding::SVGElementMethods;
use crate::dom::bindings::inheritance::Castable;
use crate::dom::bindings::root::{Dom, DomRoot, MutNullableDom};
use crate::dom::css::cssstyledeclaration::{
    CSSModificationAccess, CSSStyleDeclaration, CSSStyleOwner,
};
use crate::dom::document::Document;
use crate::dom::document::focus::FocusableArea;
use crate::dom::element::{AttributeMutation, Element};
use crate::dom::node::{Node, NodeTraits};
use crate::dom::scrolling_box::{ScrollAxisState, ScrollRequirement};
use crate::dom::virtualmethods::VirtualMethods;
use crate::script_runtime::CanGc;

#[dom_struct]
pub(crate) struct SVGElement {
    element: Element,
    style_decl: MutNullableDom<CSSStyleDeclaration>,
}

impl SVGElement {
    fn new_inherited(
        tag_name: LocalName,
        prefix: Option<Prefix>,
        document: &Document,
    ) -> SVGElement {
        SVGElement::new_inherited_with_state(ElementState::empty(), tag_name, prefix, document)
    }

    pub(crate) fn new_inherited_with_state(
        state: ElementState,
        tag_name: LocalName,
        prefix: Option<Prefix>,
        document: &Document,
    ) -> SVGElement {
        SVGElement {
            element: Element::new_inherited_with_state(state, tag_name, ns!(svg), prefix, document),
            style_decl: Default::default(),
        }
    }

    pub(crate) fn new(
        cx: &mut js::context::JSContext,
        tag_name: LocalName,
        prefix: Option<Prefix>,
        document: &Document,
        proto: Option<HandleObject>,
    ) -> DomRoot<SVGElement> {
        Node::reflect_node_with_proto(
            cx,
            Box::new(SVGElement::new_inherited(tag_name, prefix, document)),
            document,
            proto,
        )
    }

    fn as_element(&self) -> &Element {
        self.upcast::<Element>()
    }
}

impl VirtualMethods for SVGElement {
    fn super_type(&self) -> Option<&dyn VirtualMethods> {
        Some(self.as_element() as &dyn VirtualMethods)
    }

    fn attribute_mutated(
        &self,
        cx: &mut js::context::JSContext,
        attr: &Attr,
        mutation: AttributeMutation,
    ) {
        self.super_type()
            .unwrap()
            .attribute_mutated(cx, attr, mutation);
        let element = self.as_element();
        if let (&local_name!("nonce"), mutation) = (attr.local_name(), mutation) {
            match mutation {
                AttributeMutation::Set(..) => {
                    let nonce = &**attr.value();
                    element.update_nonce_internal_slot(nonce.to_owned());
                },
                AttributeMutation::Removed => {
                    element.update_nonce_internal_slot(String::new());
                },
            }
        }
    }
}

impl SVGElementMethods<crate::DomTypeHolder> for SVGElement {
    /// <https://html.spec.whatwg.org/multipage/#the-style-attribute>
    fn Style(&self) -> DomRoot<CSSStyleDeclaration> {
        self.style_decl.or_init(|| {
            let global = self.owner_window();
            CSSStyleDeclaration::new(
                &global,
                CSSStyleOwner::Element(Dom::from_ref(self.upcast())),
                None,
                CSSModificationAccess::ReadWrite,
                CanGc::deprecated_note(),
            )
        })
    }

    // https://html.spec.whatwg.org/multipage/#globaleventhandlers
    global_event_handlers!();

    /// <https://html.spec.whatwg.org/multipage/#dom-noncedelement-nonce>
    fn Nonce(&self) -> DOMString {
        self.as_element().nonce_value().into()
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-noncedelement-nonce>
    fn SetNonce(&self, value: DOMString) {
        self.as_element()
            .update_nonce_internal_slot(value.to_string())
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-fe-autofocus>
    fn Autofocus(&self) -> bool {
        self.element.has_attribute(&local_name!("autofocus"))
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-fe-autofocus>
    fn SetAutofocus(&self, autofocus: bool, can_gc: CanGc) {
        self.element
            .set_bool_attribute(&local_name!("autofocus"), autofocus, can_gc);
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-focus>
    fn Focus(&self, cx: &mut js::context::JSContext, options: &FocusOptions) {
        // 1. If the allow focus steps given this's node document return false, then return.
        // TODO: Implement this.

        // 2. Run the focusing steps for this.
        if !self
            .upcast::<Node>()
            .run_the_focusing_steps(None, CanGc::from_cx(cx))
        {
            // The specification seems to imply we should scroll into view even if this element
            // is not a focusable area. No browser does this, so we return early in that case.
            // See https://github.com/whatwg/html/issues/12231.
            return;
        }

        // > 3. If options["focusVisible"] is true, or does not exist but in an
        // >    implementation-defined  way the user agent determines it would be best to do so,
        // >    then indicate focus. TODO: Implement this.
        // TODO: Implement this.

        // > 4. If options["preventScroll"] is false, then scroll a target into view given this,
        // >    "auto", "center", and "center".
        if !options.preventScroll {
            let scroll_axis = ScrollAxisState {
                position: ScrollLogicalPosition::Center,
                requirement: ScrollRequirement::IfNotVisible,
            };
            self.upcast::<Element>().scroll_into_view_with_options(
                ScrollBehavior::Smooth,
                scroll_axis,
                scroll_axis,
                None,
                None,
            );
        }
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-blur>
    fn Blur(&self, cx: &mut js::context::JSContext) {
        // TODO: Run the unfocusing steps. Focus the top-level document, not
        //       the current document.
        if !self.as_element().focus_state() {
            return;
        }
        // <https://html.spec.whatwg.org/multipage/#unfocusing-steps>
        self.owner_document()
            .focus_handler()
            .focus(FocusableArea::Viewport, CanGc::from_cx(cx));
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-tabindex>
    fn TabIndex(&self) -> i32 {
        self.element.tab_index()
    }

    /// <https://html.spec.whatwg.org/multipage/#dom-tabindex>
    fn SetTabIndex(&self, tab_index: i32, can_gc: CanGc) {
        self.element
            .set_int_attribute(&local_name!("tabindex"), tab_index, can_gc);
    }
}