servo/components/script/dom/bluetooth/bluetoothremotegattdescriptor.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 std::rc::Rc;

use dom_struct::dom_struct;
use js::realm::CurrentRealm;
use servo_base::generic_channel::GenericSender;
use servo_bluetooth_traits::blocklist::{Blocklist, uuid_is_blocklisted};
use servo_bluetooth_traits::{BluetoothRequest, BluetoothResponse};

use crate::dom::bindings::cell::DomRefCell;
use crate::dom::bindings::codegen::Bindings::BluetoothRemoteGATTCharacteristicBinding::BluetoothRemoteGATTCharacteristicMethods;
use crate::dom::bindings::codegen::Bindings::BluetoothRemoteGATTDescriptorBinding::BluetoothRemoteGATTDescriptorMethods;
use crate::dom::bindings::codegen::Bindings::BluetoothRemoteGATTServerBinding::BluetoothRemoteGATTServerMethods;
use crate::dom::bindings::codegen::Bindings::BluetoothRemoteGATTServiceBinding::BluetoothRemoteGATTServiceMethods;
use crate::dom::bindings::codegen::UnionTypes::ArrayBufferViewOrArrayBuffer;
use crate::dom::bindings::error::Error::{self, InvalidModification, Network, Security};
use crate::dom::bindings::reflector::{DomGlobal, Reflector, reflect_dom_object_with_cx};
use crate::dom::bindings::root::{Dom, DomRoot};
use crate::dom::bindings::str::{ByteString, DOMString};
use crate::dom::bluetooth::{AsyncBluetoothListener, response_async};
use crate::dom::bluetoothremotegattcharacteristic::{
    BluetoothRemoteGATTCharacteristic, MAXIMUM_ATTRIBUTE_LENGTH,
};
use crate::dom::globalscope::GlobalScope;
use crate::dom::promise::Promise;
use crate::script_runtime::CanGc;

// http://webbluetoothcg.github.io/web-bluetooth/#bluetoothremotegattdescriptor
#[dom_struct]
pub(crate) struct BluetoothRemoteGATTDescriptor {
    reflector_: Reflector,
    characteristic: Dom<BluetoothRemoteGATTCharacteristic>,
    uuid: DOMString,
    value: DomRefCell<Option<ByteString>>,
    instance_id: String,
}

impl BluetoothRemoteGATTDescriptor {
    pub(crate) fn new_inherited(
        characteristic: &BluetoothRemoteGATTCharacteristic,
        uuid: DOMString,
        instance_id: String,
    ) -> BluetoothRemoteGATTDescriptor {
        BluetoothRemoteGATTDescriptor {
            reflector_: Reflector::new(),
            characteristic: Dom::from_ref(characteristic),
            uuid,
            value: DomRefCell::new(None),
            instance_id,
        }
    }

    pub(crate) fn new(
        cx: &mut js::context::JSContext,
        global: &GlobalScope,
        characteristic: &BluetoothRemoteGATTCharacteristic,
        uuid: DOMString,
        instance_id: String,
    ) -> DomRoot<BluetoothRemoteGATTDescriptor> {
        reflect_dom_object_with_cx(
            Box::new(BluetoothRemoteGATTDescriptor::new_inherited(
                characteristic,
                uuid,
                instance_id,
            )),
            global,
            cx,
        )
    }

    fn get_bluetooth_thread(&self) -> GenericSender<BluetoothRequest> {
        self.global().as_window().bluetooth_thread()
    }

    fn get_instance_id(&self) -> String {
        self.instance_id.clone()
    }
}

impl BluetoothRemoteGATTDescriptorMethods<crate::DomTypeHolder> for BluetoothRemoteGATTDescriptor {
    /// <https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattdescriptor-characteristic>
    fn Characteristic(&self) -> DomRoot<BluetoothRemoteGATTCharacteristic> {
        DomRoot::from_ref(&self.characteristic)
    }

    /// <https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattdescriptor-uuid>
    fn Uuid(&self) -> DOMString {
        self.uuid.clone()
    }

    /// <https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattdescriptor-value>
    fn GetValue(&self) -> Option<ByteString> {
        self.value.borrow().clone()
    }

    /// <https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattdescriptor-readvalue>
    fn ReadValue(&self, cx: &mut CurrentRealm) -> Rc<Promise> {
        let p = Promise::new_in_realm(cx);

        // Step 1.
        if uuid_is_blocklisted(&self.uuid.str(), Blocklist::Reads) {
            p.reject_error(Security(None), CanGc::from_cx(cx));
            return p;
        }

        // Step 2.
        if !self
            .Characteristic()
            .Service()
            .Device()
            .get_gatt(cx)
            .Connected()
        {
            p.reject_error(Network(None), CanGc::from_cx(cx));
            return p;
        }

        // TODO: Step 5: Implement the `connection-checking-wrapper` algorithm for BluetoothRemoteGATTServer.
        // Note: Steps 3 - 4 and substeps of Step 5 are implemented in components/bluetooth/lib.rs
        // in readValue function and in handle_response function.
        let sender = response_async(&p, self);
        self.get_bluetooth_thread()
            .send(BluetoothRequest::ReadValue(self.get_instance_id(), sender))
            .unwrap();
        p
    }

    /// <https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattdescriptor-writevalue>
    fn WriteValue(
        &self,
        cx: &mut CurrentRealm,
        value: ArrayBufferViewOrArrayBuffer,
    ) -> Rc<Promise> {
        let p = Promise::new_in_realm(cx);

        // Step 1.
        if uuid_is_blocklisted(&self.uuid.str(), Blocklist::Writes) {
            p.reject_error(Security(None), CanGc::from_cx(cx));
            return p;
        }

        // Step 2 - 3.
        let vec = match value {
            ArrayBufferViewOrArrayBuffer::ArrayBufferView(avb) => avb.to_vec(),
            ArrayBufferViewOrArrayBuffer::ArrayBuffer(ab) => ab.to_vec(),
        };
        if vec.len() > MAXIMUM_ATTRIBUTE_LENGTH {
            p.reject_error(InvalidModification(None), CanGc::from_cx(cx));
            return p;
        }

        // Step 4.
        if !self
            .Characteristic()
            .Service()
            .Device()
            .get_gatt(cx)
            .Connected()
        {
            p.reject_error(Network(None), CanGc::from_cx(cx));
            return p;
        }

        // TODO: Step 7: Implement the `connection-checking-wrapper` algorithm for BluetoothRemoteGATTServer.
        // Note: Steps 5 - 6 and substeps of Step 7 are implemented in components/bluetooth/lib.rs
        // in writeValue function and in handle_response function.
        let sender = response_async(&p, self);
        self.get_bluetooth_thread()
            .send(BluetoothRequest::WriteValue(
                self.get_instance_id(),
                vec,
                sender,
            ))
            .unwrap();
        p
    }
}

impl AsyncBluetoothListener for BluetoothRemoteGATTDescriptor {
    fn handle_response(
        &self,
        cx: &mut js::context::JSContext,
        response: BluetoothResponse,
        promise: &Rc<Promise>,
    ) {
        match response {
            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattdescriptor-readvalue
            BluetoothResponse::ReadValue(result) => {
                // TODO: Step 5.4.1: Implement activeAlgorithms internal slot for BluetoothRemoteGATTServer.

                // Step 5.4.2.
                // TODO(#5014): Replace ByteString with ArrayBuffer when it is implemented.
                let value = ByteString::new(result);
                *self.value.borrow_mut() = Some(value.clone());

                // Step 5.4.3.
                promise.resolve_native(&value, CanGc::from_cx(cx));
            },
            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothremotegattdescriptor-writevalue
            BluetoothResponse::WriteValue(result) => {
                // TODO: Step 7.4.1: Implement activeAlgorithms internal slot for BluetoothRemoteGATTServer.

                // Step 7.4.2.
                // TODO(#5014): Replace ByteString with an ArrayBuffer wrapped in a DataView.
                *self.value.borrow_mut() = Some(ByteString::new(result));

                // Step 7.4.3.
                // TODO: Resolve promise with undefined instead of a value.
                promise.resolve_native(&(), CanGc::from_cx(cx));
            },
            _ => promise.reject_error(
                Error::Type(c"Something went wrong...".to_owned()),
                CanGc::from_cx(cx),
            ),
        }
    }
}