/*
 * Copyright (C) 2021 The Android Open Source Project
 *
 * 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.
 */

#include <gtest/gtest.h>

#include "adaptivecpu/CpuFrequencyReader.h"
#include "mocks.h"

using testing::_;
using testing::ByMove;
using testing::Return;
using std::chrono_literals::operator""ms;

namespace aidl {
namespace google {
namespace hardware {
namespace power {
namespace impl {
namespace pixel {

std::ostream &operator<<(std::ostream &stream, const CpuPolicyAverageFrequency &frequency) {
    return stream << "CpuPolicyAverageFrequency(" << frequency.policyId << ", "
                  << frequency.averageFrequencyHz << ")";
}

TEST(CpuFrequencyReaderTest, cpuPolicyIds) {
    std::unique_ptr<MockFilesystem> filesystem = std::make_unique<MockFilesystem>();
    EXPECT_CALL(*filesystem, ListDirectory("/sys/devices/system/cpu/cpufreq", _))
            .WillOnce([](auto _path __attribute__((unused)), auto result) {
                *result = std::vector<std::string>{"ignored1", "policy1",  "ignored2",
                                                   "policy5",  "policy10", "policybad"};
                return true;
            });
    EXPECT_CALL(*filesystem, ReadFileStream(_, _))
            .WillRepeatedly([](auto _path __attribute__((unused)), auto result) {
                *result = std::make_unique<std::istringstream>("1 2\n3 4\n");
                return true;
            });

    CpuFrequencyReader reader(std::move(filesystem));
    EXPECT_TRUE(reader.Init());

    std::map<uint32_t, std::map<uint64_t, std::chrono::milliseconds>> expected = {
            {1, {{1, 20ms}, {3, 40ms}}}, {5, {{1, 20ms}, {3, 40ms}}}, {10, {{1, 20ms}, {3, 40ms}}}};
    EXPECT_EQ(reader.GetPreviousCpuPolicyFrequencies(), expected);
}

TEST(CpuFrequencyReaderTest, getRecentCpuPolicyFrequencies) {
    std::unique_ptr<MockFilesystem> filesystem = std::make_unique<MockFilesystem>();
    EXPECT_CALL(*filesystem, ListDirectory("/sys/devices/system/cpu/cpufreq", _))
            .WillOnce([](auto _path __attribute__((unused)), auto result) {
                *result = std::vector<std::string>{"policy1", "policy2"};
                return true;
            });
    EXPECT_CALL(*filesystem,
                ReadFileStream("/sys/devices/system/cpu/cpufreq/policy1/stats/time_in_state", _))
            .Times(2)
            .WillOnce([](auto _path __attribute__((unused)), auto result) {
                *result = std::make_unique<std::istringstream>("1000 5\n2000 4");
                return true;
            })
            .WillOnce([](auto _path __attribute__((unused)), auto result) {
                *result = std::make_unique<std::istringstream>("1000 7\n2000 10");
                return true;
            });
    EXPECT_CALL(*filesystem,
                ReadFileStream("/sys/devices/system/cpu/cpufreq/policy2/stats/time_in_state", _))
            .Times(2)
            .WillOnce([](auto _path __attribute__((unused)), auto result) {
                *result = std::make_unique<std::istringstream>("1500 1\n2500 23");
                return true;
            })
            .WillOnce([](auto _path __attribute__((unused)), auto result) {
                *result = std::make_unique<std::istringstream>("1500 5\n2500 23");
                return true;
            });

    CpuFrequencyReader reader(std::move(filesystem));
    EXPECT_TRUE(reader.Init());

    std::vector<CpuPolicyAverageFrequency> actual;
    EXPECT_TRUE(reader.GetRecentCpuPolicyFrequencies(&actual));
    EXPECT_EQ(actual, std::vector<CpuPolicyAverageFrequency>({
                              {.policyId = 1, .averageFrequencyHz = 1750},
                              {.policyId = 2, .averageFrequencyHz = 1500},
                      }));
}

TEST(CpuFrequencyReaderTest, getRecentCpuPolicyFrequencies_frequenciesChange) {
    std::unique_ptr<MockFilesystem> filesystem = std::make_unique<MockFilesystem>();
    EXPECT_CALL(*filesystem, ListDirectory("/sys/devices/system/cpu/cpufreq", _))
            .WillOnce([](auto _path __attribute__((unused)), auto result) {
                *result = std::vector<std::string>{"policy1"};
                return true;
            });
    EXPECT_CALL(*filesystem,
                ReadFileStream("/sys/devices/system/cpu/cpufreq/policy1/stats/time_in_state", _))
            .Times(2)
            .WillOnce([](auto _path __attribute__((unused)), auto result) {
                *result = std::make_unique<std::istringstream>("1000 5\n2000 4");
                return true;
            })
            .WillOnce([](auto _path __attribute__((unused)), auto result) {
                *result = std::make_unique<std::istringstream>("1000 6\n2001 4");
                return true;
            });

    CpuFrequencyReader reader(std::move(filesystem));
    EXPECT_TRUE(reader.Init());

    std::vector<CpuPolicyAverageFrequency> actual;
    EXPECT_FALSE(reader.GetRecentCpuPolicyFrequencies(&actual));
}

TEST(CpuFrequencyReaderTest, getRecentCpuPolicyFrequencies_badFormat) {
    std::unique_ptr<MockFilesystem> filesystem = std::make_unique<MockFilesystem>();
    EXPECT_CALL(*filesystem, ListDirectory("/sys/devices/system/cpu/cpufreq", _))
            .WillOnce([](auto _path __attribute__((unused)), auto result) {
                *result = std::vector<std::string>{"policy1"};
                return true;
            });
    EXPECT_CALL(*filesystem,
                ReadFileStream("/sys/devices/system/cpu/cpufreq/policy1/stats/time_in_state", _))
            .Times(2)
            .WillOnce([](auto _path __attribute__((unused)), auto result) {
                *result = std::make_unique<std::istringstream>("1000 1");
                return true;
            })
            .WillOnce([](auto _path __attribute__((unused)), auto result) {
                *result = std::make_unique<std::istringstream>("1000 2\nfoo");
                return true;
            });

    CpuFrequencyReader reader(std::move(filesystem));
    EXPECT_TRUE(reader.Init());

    std::vector<CpuPolicyAverageFrequency> actual;
    EXPECT_FALSE(reader.GetRecentCpuPolicyFrequencies(&actual));
}

}  // namespace pixel
}  // namespace impl
}  // namespace power
}  // namespace hardware
}  // namespace google
}  // namespace aidl