Home | History | Annotate | Download | only in battery 
      1 // Copyright 2014 The Chromium Authors. All rights reserved.
      2 // Use of this source code is governed by a BSD-style license that can be
      3 // found in the LICENSE file.
      4 
      5 #include "config.h"
      6 #include "modules/battery/BatteryManager.h"
      7 
      8 #include "core/dom/Document.h"
      9 #include "core/events/Event.h"
     10 #include "modules/battery/BatteryDispatcher.h"
     11 #include "modules/battery/BatteryStatus.h"
     12 #include "platform/RuntimeEnabledFeatures.h"
     13 
     14 namespace blink {
     15 
     16 BatteryManager* BatteryManager::create(ExecutionContext* context)
     17 {
     18     BatteryManager* batteryManager = new BatteryManager(context);
     19     batteryManager->suspendIfNeeded();
     20     return batteryManager;
     21 }
     22 
     23 BatteryManager::~BatteryManager()
     24 {
     25     stopUpdating();
     26 }
     27 
     28 BatteryManager::BatteryManager(ExecutionContext* context)
     29     : ActiveDOMObject(context)
     30     , PlatformEventController(toDocument(context)->page())
     31     , m_batteryStatus(BatteryStatus::create())
     32     , m_state(NotStarted)
     33 {
     34 }
     35 
     36 ScriptPromise BatteryManager::startRequest(ScriptState* scriptState)
     37 {
     38     if (m_state == Pending)
     39         return m_resolver->promise();
     40 
     41     m_resolver = ScriptPromiseResolver::create(scriptState);
     42     ScriptPromise promise = m_resolver->promise();
     43 
     44     if (m_state == Resolved) {
     45         // FIXME: Consider returning the same promise in this case. See crbug.com/385025.
     46         m_resolver->resolve(this);
     47     } else if (m_state == NotStarted) {
     48         m_state = Pending;
     49         m_hasEventListener = true;
     50         startUpdating();
     51     }
     52 
     53     return promise;
     54 }
     55 
     56 bool BatteryManager::charging()
     57 {
     58     return m_batteryStatus->charging();
     59 }
     60 
     61 double BatteryManager::chargingTime()
     62 {
     63     return m_batteryStatus->chargingTime();
     64 }
     65 
     66 double BatteryManager::dischargingTime()
     67 {
     68     return m_batteryStatus->dischargingTime();
     69 }
     70 
     71 double BatteryManager::level()
     72 {
     73     return m_batteryStatus->level();
     74 }
     75 
     76 void BatteryManager::didUpdateData()
     77 {
     78     ASSERT(RuntimeEnabledFeatures::batteryStatusEnabled());
     79     ASSERT(m_state != NotStarted);
     80 
     81     BatteryStatus* oldStatus = m_batteryStatus;
     82     m_batteryStatus = BatteryDispatcher::instance().latestData();
     83 
     84     if (m_state == Pending) {
     85         ASSERT(m_resolver);
     86         m_state = Resolved;
     87         m_resolver->resolve(this);
     88         return;
     89     }
     90 
     91     Document* document = toDocument(executionContext());
     92     if (document->activeDOMObjectsAreSuspended() || document->activeDOMObjectsAreStopped())
     93         return;
     94 
     95     ASSERT(oldStatus);
     96 
     97     if (m_batteryStatus->charging() != oldStatus->charging())
     98         dispatchEvent(Event::create(EventTypeNames::chargingchange));
     99     if (m_batteryStatus->chargingTime() != oldStatus->chargingTime())
    100         dispatchEvent(Event::create(EventTypeNames::chargingtimechange));
    101     if (m_batteryStatus->dischargingTime() != oldStatus->dischargingTime())
    102         dispatchEvent(Event::create(EventTypeNames::dischargingtimechange));
    103     if (m_batteryStatus->level() != oldStatus->level())
    104         dispatchEvent(Event::create(EventTypeNames::levelchange));
    105 }
    106 
    107 void BatteryManager::registerWithDispatcher()
    108 {
    109     BatteryDispatcher::instance().addController(this);
    110 }
    111 
    112 void BatteryManager::unregisterWithDispatcher()
    113 {
    114     BatteryDispatcher::instance().removeController(this);
    115 }
    116 
    117 bool BatteryManager::hasLastData()
    118 {
    119     return BatteryDispatcher::instance().latestData();
    120 }
    121 
    122 void BatteryManager::suspend()
    123 {
    124     m_hasEventListener = false;
    125     stopUpdating();
    126 }
    127 
    128 void BatteryManager::resume()
    129 {
    130     m_hasEventListener = true;
    131     startUpdating();
    132 }
    133 
    134 void BatteryManager::stop()
    135 {
    136     m_hasEventListener = false;
    137     m_state = NotStarted;
    138     stopUpdating();
    139 }
    140 
    141 bool BatteryManager::hasPendingActivity() const
    142 {
    143     // Prevent V8 from garbage collecting the wrapper object if there are
    144     // event listeners attached to it.
    145     return m_state == Resolved && hasEventListeners();
    146 }
    147 
    148 void BatteryManager::trace(Visitor* visitor)
    149 {
    150     visitor->trace(m_batteryStatus);
    151     EventTargetWithInlineData::trace(visitor);
    152 }
    153 
    154 } // namespace blink
    155