soumya92/barista

// Copyright 2018 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

// Package bluetooth provides modules for watching the status of Bluetooth adapters and devices.
package bluetooth // import "barista.run/modules/bluetooth"

import (
    "strings"

    godbus "github.com/godbus/dbus/v5"

    "barista.run/bar"
    "barista.run/base/value"
    "barista.run/base/watchers/dbus"
)

// DeviceModule represents a Bluetooth devices bar module.
type DeviceModule struct {
    path       string
    outputFunc value.Value
}

// DeviceInfo represents Bluetooth device information.
type DeviceInfo struct {
    Name      string
    Alias     string
    Address   string
    Adapter   string
    Battery   int
    Paired    bool
    Connected bool
    Trusted   bool
    Blocked   bool
}

// Device constructs a bluetooth device module instance for the given adapter and MAC address.
func Device(adapter, mac string) *DeviceModule {
    macPath := strings.Replace(strings.ToUpper(mac), ":", "_", -1)
    return &DeviceModule{path: "/org/bluez/" + adapter + "/dev_" + macPath}
}

// Output configures a module to display the output of a user-defined function.
func (m *DeviceModule) Output(outputFunc func(DeviceInfo) bar.Output) *DeviceModule {
    m.outputFunc.Set(outputFunc)
    return m
}

// Stream starts the module.
func (m *DeviceModule) Stream(sink bar.Sink) {
    w := dbus.WatchProperties(
        busType,
        "org.bluez",
        m.path,
        "org.bluez.Device1",
    ).
        Add("Name", "Alias", "Address", "Adapter", "Paired", "Connected", "Trusted", "Blocked")
    defer w.Unsubscribe()

    batt := dbus.WatchProperties(
        busType,
        "org.bluez",
        m.path,
        "org.bluez.Battery1",
    ).Add("Percentage")
    defer batt.Unsubscribe()

    outputFunc := m.outputFunc.Get().(func(DeviceInfo) bar.Output)
    nextOutputFunc, done := m.outputFunc.Subscribe()
    defer done()

    info := getDeviceInfo(w, batt)
    for {
        sink.Output(outputFunc(info))
        select {
        case <-w.Updates:
            info = getDeviceInfo(w, batt)
        case <-batt.Updates:
            info = getDeviceInfo(w, batt)
        case <-nextOutputFunc:
            outputFunc = m.outputFunc.Get().(func(DeviceInfo) bar.Output)
        }
    }
}

func getDeviceInfo(w, batt *dbus.PropertiesWatcher) DeviceInfo {
    i := DeviceInfo{}
    props := w.Get()

    i.Name, _ = props["Name"].(string)
    i.Alias, _ = props["Alias"].(string)
    i.Address, _ = props["Address"].(string)

    if adapter, ok := props["Adapter"].(godbus.ObjectPath); ok {
        i.Adapter = string(adapter)
    }

    i.Paired, _ = props["Paired"].(bool)
    i.Connected, _ = props["Connected"].(bool)
    i.Trusted, _ = props["Trusted"].(bool)
    i.Blocked, _ = props["Blocked"].(bool)
    if battery, ok := batt.Get()["Percentage"].(byte); ok {
        i.Battery = int(battery)
    }
    return i
}