1 /*
2  * Copyright (C) 2021 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #pragma once
18 
19 #include <PowerStats.h>
20 
21 #include <android-base/chrono_utils.h>
22 
23 #include <chrono>
24 #include <random>
25 
26 namespace aidl {
27 namespace android {
28 namespace hardware {
29 namespace power {
30 namespace stats {
31 
32 class FakeEnergyConsumer : public PowerStats::IEnergyConsumer {
33   public:
FakeEnergyConsumer(EnergyConsumerType type,std::string name)34     FakeEnergyConsumer(EnergyConsumerType type, std::string name) : mType(type), mName(name) {
35         mResult.timestampMs = 0;
36         mResult.energyUWs = 0;
37         mResult.attribution = {};
38     }
39 
40     ~FakeEnergyConsumer() = default;
41 
getName()42     std::string getName() override { return mName; }
43 
getType()44     EnergyConsumerType getType() override { return mType; }
45 
getEnergyConsumed()46     std::optional<EnergyConsumerResult> getEnergyConsumed() override {
47         mFakeEnergyConsumerResult.update(&mResult);
48         return mResult;
49     }
50 
51   private:
52     class FakeEnergyConsumerResult {
53       public:
FakeEnergyConsumerResult()54         FakeEnergyConsumerResult() : mDistribution(1, 100) {}
update(EnergyConsumerResult * result)55         void update(EnergyConsumerResult* result) {
56             // generates number in the range 1..100
57             auto randNum = std::bind(mDistribution, mGenerator);
58 
59             // Get current time since boot in milliseconds
60             uint64_t now = std::chrono::time_point_cast<std::chrono::milliseconds>(
61                                    ::android::base::boot_clock::now())
62                                    .time_since_epoch()
63                                    .count();
64             result->timestampMs = now;
65             result->energyUWs += randNum() * 100;
66         }
67 
68       private:
69         std::default_random_engine mGenerator;
70         std::uniform_int_distribution<int> mDistribution;
71     };
72 
73     EnergyConsumerType mType;
74     std::string mName;
75     FakeEnergyConsumerResult mFakeEnergyConsumerResult;
76     EnergyConsumerResult mResult;
77 };
78 
79 }  // namespace stats
80 }  // namespace power
81 }  // namespace hardware
82 }  // namespace android
83 }  // namespace aidl