servo-script 0.5.0

A component of the servo web-engine.
Documentation
/* 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 std::cell::Cell;
use std::rc::Rc;

use dom_struct::dom_struct;
use embedder_traits::{AllowOrDeny, EmbedderMsg};
use js::context::JSContext;
use js::realm::CurrentRealm;
use script_bindings::reflector::{Reflector, reflect_dom_object_with_cx};
use servo_constellation_traits::ScriptToConstellationMessage;

use crate::conversions::Convert;
use crate::dom::bindings::codegen::Bindings::DocumentBinding::{
    DocumentMethods, DocumentVisibilityState,
};
use crate::dom::bindings::codegen::Bindings::WakeLockBinding::{WakeLockMethods, WakeLockType};
use crate::dom::bindings::codegen::Bindings::WindowBinding::WindowMethods;
use crate::dom::bindings::error::Error;
use crate::dom::bindings::reflector::DomGlobal;
use crate::dom::bindings::root::DomRoot;
use crate::dom::globalscope::GlobalScope;
use crate::dom::promise::Promise;
use crate::dom::wakelock::wakelocksentinel::WakeLockSentinel;
use crate::routed_promise::{RoutedPromiseListener, callback_promise};

/// <https://w3c.github.io/screen-wake-lock/#the-wakelock-interface>
#[dom_struct]
pub(crate) struct WakeLock {
    reflector_: Reflector,
    type_: Cell<WakeLockType>,
}

impl WakeLock {
    pub(crate) fn new_inherited() -> Self {
        Self {
            reflector_: Reflector::new(),
            type_: Cell::new(WakeLockType::Screen),
        }
    }

    pub(crate) fn new(cx: &mut js::context::JSContext, global: &GlobalScope) -> DomRoot<Self> {
        reflect_dom_object_with_cx(Box::new(Self::new_inherited()), global, cx)
    }
}

impl WakeLockMethods<crate::DomTypeHolder> for WakeLock {
    /// <https://w3c.github.io/screen-wake-lock/#the-request-method>
    fn Request(&self, cx: &mut CurrentRealm, type_: WakeLockType) -> Rc<Promise> {
        let global = GlobalScope::from_current_realm(cx);
        let promise = Promise::new_in_realm(cx);

        // Step 1. Let document be this's relevant global object's associated Document.
        let document = global.as_window().Document();

        // Step 2. If document is not fully active, reject with NotAllowedError.
        if !document.is_fully_active() {
            promise.reject_error(cx, Error::NotAllowed(Some(
                        "Failed to execute 'request' on 'WakeLock': The requesting page is not fully active."
                        .to_string())));
            return promise;
        }

        // Step 3. If document's visibility state is "hidden", reject with NotAllowedError.
        if document.VisibilityState() == DocumentVisibilityState::Hidden {
            promise.reject_error(cx, Error::NotAllowed(Some(
                        "Failed to execute 'request' on 'WakeLock': The requesting page is not visible."
                        .to_string()
                        )));
            return promise;
        }

        // Step 4. Obtain permission for "screen-wake-lock".
        // <https://w3c.github.io/screen-wake-lock/#dfn-obtain-permission>
        let Some(webview_id) = global.webview_id() else {
            promise.reject_error(
                cx,
                Error::NotAllowed(Some("Unable to obtain WakeLock permission.".to_string())),
            );
            return promise;
        };

        self.type_.set(type_);
        let task_manager = global.task_manager();
        let task_source = task_manager.dom_manipulation_task_source();
        let callback = callback_promise(&promise, self, task_source);
        global.send_to_embedder(EmbedderMsg::RequestWakeLockPermission(
            webview_id,
            callback,
            self.type_.get().convert(),
        ));

        promise
    }
}

impl RoutedPromiseListener<AllowOrDeny> for WakeLock {
    /// <https://w3c.github.io/screen-wake-lock/#the-request-method>
    fn handle_response(&self, cx: &mut JSContext, response: AllowOrDeny, promise: &Rc<Promise>) {
        match response {
            // Step 7a. If permission is denied, reject with NotAllowedError.
            AllowOrDeny::Deny => {
                promise.reject_error(
                    cx,
                    Error::NotAllowed(Some(
                        "Failed to execute 'request' on 'WakeLock': Permission denied.".to_string(),
                    )),
                );
            },
            // Step 7b-7c. Acquire the lock and resolve with a WakeLockSentinel.
            AllowOrDeny::Allow => {
                let global = self.global();
                global.as_window().send_to_constellation(
                    ScriptToConstellationMessage::AcquireWakeLock(self.type_.get().convert()),
                );

                let sentinel = WakeLockSentinel::new(cx, &global, self.type_.get());
                promise.resolve_native(cx, &sentinel);
            },
        }
    }
}

impl Convert<embedder_traits::WakeLockType> for WakeLockType {
    fn convert(self) -> embedder_traits::WakeLockType {
        match self {
            WakeLockType::Screen => embedder_traits::WakeLockType::Screen,
        }
    }
}