/* 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 http://mozilla.org/MPL/2.0/. */

use bluetooth_traits::{BluetoothCharacteristicMsg, BluetoothDescriptorMsg};
use bluetooth_traits::{BluetoothRequest, BluetoothResponse, BluetoothServiceMsg};
use dom::bindings::cell::DOMRefCell;
use dom::bindings::codegen::Bindings::BluetoothDeviceBinding;
use dom::bindings::codegen::Bindings::BluetoothDeviceBinding::BluetoothDeviceMethods;
use dom::bindings::codegen::Bindings::BluetoothRemoteGATTServerBinding::BluetoothRemoteGATTServerMethods;
use dom::bindings::codegen::Bindings::EventHandlerBinding::EventHandlerNonNull;
use dom::bindings::error::Error;
use dom::bindings::error::ErrorResult;
use dom::bindings::inheritance::Castable;
use dom::bindings::js::{JS, MutNullableJS, Root};
use dom::bindings::reflector::{DomObject, reflect_dom_object};
use dom::bindings::str::DOMString;
use dom::bluetooth::{AsyncBluetoothListener, Bluetooth, response_async};
use dom::bluetoothcharacteristicproperties::BluetoothCharacteristicProperties;
use dom::bluetoothremotegattcharacteristic::BluetoothRemoteGATTCharacteristic;
use dom::bluetoothremotegattdescriptor::BluetoothRemoteGATTDescriptor;
use dom::bluetoothremotegattserver::BluetoothRemoteGATTServer;
use dom::bluetoothremotegattservice::BluetoothRemoteGATTService;
use dom::eventtarget::EventTarget;
use dom::globalscope::GlobalScope;
use dom::promise::Promise;
use ipc_channel::ipc::{self, IpcSender};
use js::jsapi::JSContext;
use std::cell::Cell;
use std::collections::HashMap;
use std::rc::Rc;

// https://webbluetoothcg.github.io/web-bluetooth/#bluetoothdevice
#[dom_struct]
pub struct BluetoothDevice {
    eventtarget: EventTarget,
    id: DOMString,
    name: Option<DOMString>,
    gatt: MutNullableJS<BluetoothRemoteGATTServer>,
    context: JS<Bluetooth>,
    attribute_instance_map: (DOMRefCell<HashMap<String, JS<BluetoothRemoteGATTService>>>,
                             DOMRefCell<HashMap<String, JS<BluetoothRemoteGATTCharacteristic>>>,
                             DOMRefCell<HashMap<String, JS<BluetoothRemoteGATTDescriptor>>>),
    watching_advertisements: Cell<bool>,
}

impl BluetoothDevice {
    pub fn new_inherited(id: DOMString,
                         name: Option<DOMString>,
                         context: &Bluetooth)
                         -> BluetoothDevice {
        BluetoothDevice {
            eventtarget: EventTarget::new_inherited(),
            id: id,
            name: name,
            gatt: Default::default(),
            context: JS::from_ref(context),
            attribute_instance_map: (DOMRefCell::new(HashMap::new()),
                                     DOMRefCell::new(HashMap::new()),
                                     DOMRefCell::new(HashMap::new())),
            watching_advertisements: Cell::new(false),
        }
    }

    pub fn new(global: &GlobalScope,
               id: DOMString,
               name: Option<DOMString>,
               context: &Bluetooth)
               -> Root<BluetoothDevice> {
        reflect_dom_object(box BluetoothDevice::new_inherited(id,
                                                              name,
                                                              context),
                           global,
                           BluetoothDeviceBinding::Wrap)
    }

    fn get_context(&self) -> Root<Bluetooth> {
        Root::from_ref(&self.context)
    }

    pub fn get_or_create_service(&self,
                                 service: &BluetoothServiceMsg,
                                 server: &BluetoothRemoteGATTServer)
                                 -> Root<BluetoothRemoteGATTService> {
        let (ref service_map_ref, _, _) = self.attribute_instance_map;
        let mut service_map = service_map_ref.borrow_mut();
        if let Some(existing_service) = service_map.get(&service.instance_id) {
            return Root::from_ref(&existing_service);
        }
        let bt_service = BluetoothRemoteGATTService::new(&server.global(),
                                                         &server.Device(),
                                                         DOMString::from(service.uuid.clone()),
                                                         service.is_primary,
                                                         service.instance_id.clone());
        service_map.insert(service.instance_id.clone(), JS::from_ref(&bt_service));
        return bt_service;
    }

    pub fn get_or_create_characteristic(&self,
                                        characteristic: &BluetoothCharacteristicMsg,
                                        service: &BluetoothRemoteGATTService)
                                        -> Root<BluetoothRemoteGATTCharacteristic> {
        let (_, ref characteristic_map_ref, _) = self.attribute_instance_map;
        let mut characteristic_map = characteristic_map_ref.borrow_mut();
        if let Some(existing_characteristic) = characteristic_map.get(&characteristic.instance_id) {
            return Root::from_ref(&existing_characteristic);
        }
        let properties =
            BluetoothCharacteristicProperties::new(&service.global(),
                                                   characteristic.broadcast,
                                                   characteristic.read,
                                                   characteristic.write_without_response,
                                                   characteristic.write,
                                                   characteristic.notify,
                                                   characteristic.indicate,
                                                   characteristic.authenticated_signed_writes,
                                                   characteristic.reliable_write,
                                                   characteristic.writable_auxiliaries);
        let bt_characteristic = BluetoothRemoteGATTCharacteristic::new(&service.global(),
                                                                       service,
                                                                       DOMString::from(characteristic.uuid.clone()),
                                                                       &properties,
                                                                       characteristic.instance_id.clone());
        characteristic_map.insert(characteristic.instance_id.clone(), JS::from_ref(&bt_characteristic));
        return bt_characteristic;
    }

    pub fn is_represented_device_null(&self) -> bool {
        let (sender, receiver) = ipc::channel().unwrap();
        self.get_bluetooth_thread().send(
            BluetoothRequest::IsRepresentedDeviceNull(self.Id().to_string(), sender)).unwrap();
        receiver.recv().unwrap()
    }

    pub fn get_or_create_descriptor(&self,
                                    descriptor: &BluetoothDescriptorMsg,
                                    characteristic: &BluetoothRemoteGATTCharacteristic)
                                    -> Root<BluetoothRemoteGATTDescriptor> {
        let (_, _, ref descriptor_map_ref) = self.attribute_instance_map;
        let mut descriptor_map = descriptor_map_ref.borrow_mut();
        if let Some(existing_descriptor) = descriptor_map.get(&descriptor.instance_id) {
            return Root::from_ref(&existing_descriptor);
        }
        let bt_descriptor = BluetoothRemoteGATTDescriptor::new(&characteristic.global(),
                                                               characteristic,
                                                               DOMString::from(descriptor.uuid.clone()),
                                                               descriptor.instance_id.clone());
        descriptor_map.insert(descriptor.instance_id.clone(), JS::from_ref(&bt_descriptor));
        return bt_descriptor;
    }

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

    // https://webbluetoothcg.github.io/web-bluetooth/#clean-up-the-disconnected-device
    #[allow(unrooted_must_root)]
    pub fn clean_up_disconnected_device(&self) {
        // Step 1.
        self.Gatt().set_connected(false);

        // TODO: Step 2: Implement activeAlgorithms internal slot for BluetoothRemoteGATTServer.

        // Step 3: We don't need `context`, we get the attributeInstanceMap from the device.
        // https://github.com/WebBluetoothCG/web-bluetooth/issues/330

        // Step 4.
        let mut service_map = self.attribute_instance_map.0.borrow_mut();
        let service_ids = service_map.drain().map(|(id, _)| id).collect();

        let mut characteristic_map = self.attribute_instance_map.1.borrow_mut();
        let characteristic_ids = characteristic_map.drain().map(|(id, _)| id).collect();

        let mut descriptor_map = self.attribute_instance_map.2.borrow_mut();
        let descriptor_ids = descriptor_map.drain().map(|(id, _)| id).collect();

        // Step 5, 6.4, 7.
        // TODO: Step 6: Implement `active notification context set` for BluetoothRemoteGATTCharacteristic.
        let _ = self.get_bluetooth_thread().send(
                     BluetoothRequest::SetRepresentedToNull(service_ids, characteristic_ids, descriptor_ids));

        // Step 8.
        self.upcast::<EventTarget>().fire_bubbling_event(atom!("gattserverdisconnected"));
    }

    // https://webbluetoothcg.github.io/web-bluetooth/#garbage-collect-the-connection
    #[allow(unrooted_must_root)]
    pub fn garbage_collect_the_connection(&self) -> ErrorResult {
        // Step 1: TODO: Check if other systems using this device.

        // Step 2.
        let context = self.get_context();
        for (id, device) in context.get_device_map().borrow().iter() {
            // Step 2.1 - 2.2.
            if id == &self.Id().to_string() {
                if device.Gatt().Connected() {
                    return Ok(());
                }
                // TODO: Step 2.3: Implement activeAlgorithms internal slot for BluetoothRemoteGATTServer.
            }
        }

        // Step 3.
        let (sender, receiver) = ipc::channel().unwrap();
        self.get_bluetooth_thread().send(
            BluetoothRequest::GATTServerDisconnect(String::from(self.Id()), sender)).unwrap();
        receiver.recv().unwrap().map_err(Error::from)
    }
}

impl BluetoothDeviceMethods for BluetoothDevice {
     // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothdevice-id
    fn Id(&self) -> DOMString {
        self.id.clone()
    }

    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothdevice-name
    fn GetName(&self) -> Option<DOMString> {
        self.name.clone()
    }

    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothdevice-gatt
    fn Gatt(&self) -> Root<BluetoothRemoteGATTServer> {
        // TODO: Step 1 - 2: Implement the Permission API.
        self.gatt.or_init(|| {
            BluetoothRemoteGATTServer::new(&self.global(), self)
        })
    }

    #[allow(unrooted_must_root)]
    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothdevice-watchadvertisements
    fn WatchAdvertisements(&self) -> Rc<Promise> {
        let p = Promise::new(&self.global());
        let sender = response_async(&p, self);
        // TODO: Step 1.
        // Note: Steps 2 - 3 are implemented in components/bluetooth/lib.rs in watch_advertisements function
        // and in handle_response function.
        self.get_bluetooth_thread().send(
            BluetoothRequest::WatchAdvertisements(String::from(self.Id()), sender)).unwrap();
        return p;
    }

    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothdevice-unwatchadvertisements
    fn UnwatchAdvertisements(&self) -> () {
        // Step 1.
        self.watching_advertisements.set(false)
        // TODO: Step 2.
    }

    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothdevice-watchingadvertisements
    fn WatchingAdvertisements(&self) -> bool {
        self.watching_advertisements.get()
    }

    // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothdeviceeventhandlers-ongattserverdisconnected
    event_handler!(gattserverdisconnected, GetOngattserverdisconnected, SetOngattserverdisconnected);
}

impl AsyncBluetoothListener for BluetoothDevice {
    fn handle_response(&self, response: BluetoothResponse, promise_cx: *mut JSContext, promise: &Rc<Promise>) {
        match response {
            // https://webbluetoothcg.github.io/web-bluetooth/#dom-bluetoothdevice-unwatchadvertisements
            BluetoothResponse::WatchAdvertisements(_result) => {
                // Step 3.1.
                self.watching_advertisements.set(true);
                // Step 3.2.
                promise.resolve_native(promise_cx, &());
            },
            _ => promise.reject_error(promise_cx, Error::Type("Something went wrong...".to_owned())),
        }
    }
}