/*
 * 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.
 */

#define LOG_TAG "VehiclePropertyStore"
#include <utils/Log.h>

#include "VehiclePropertyStore.h"

#include <VehicleHalTypes.h>
#include <VehicleUtils.h>
#include <android-base/stringprintf.h>
#include <math/HashCombine.h>

#include <inttypes.h>

namespace android {
namespace hardware {
namespace automotive {
namespace vehicle {

using ::aidl::android::hardware::automotive::vehicle::StatusCode;
using ::aidl::android::hardware::automotive::vehicle::VehicleAreaConfig;
using ::aidl::android::hardware::automotive::vehicle::VehiclePropConfig;
using ::aidl::android::hardware::automotive::vehicle::VehiclePropertyStatus;
using ::aidl::android::hardware::automotive::vehicle::VehiclePropValue;
using ::android::base::Result;
using ::android::base::StringPrintf;

bool VehiclePropertyStore::RecordId::operator==(const VehiclePropertyStore::RecordId& other) const {
    return area == other.area && token == other.token;
}

std::string VehiclePropertyStore::RecordId::toString() const {
    return StringPrintf("RecordID{{.areaId=% " PRId32 ", .token=%" PRId64 "}", area, token);
}

size_t VehiclePropertyStore::RecordIdHash::operator()(RecordId const& recordId) const {
    size_t res = 0;
    hashCombine(res, recordId.area);
    hashCombine(res, recordId.token);
    return res;
}

VehiclePropertyStore::~VehiclePropertyStore() {
    std::scoped_lock<std::mutex> lockGuard(mLock);

    // Recycling record requires mValuePool, so need to recycle them before destroying mValuePool.
    mRecordsByPropId.clear();
    mValuePool.reset();
}

const VehiclePropertyStore::Record* VehiclePropertyStore::getRecordLocked(int32_t propId) const
        REQUIRES(mLock) {
    auto RecordIt = mRecordsByPropId.find(propId);
    return RecordIt == mRecordsByPropId.end() ? nullptr : &RecordIt->second;
}

VehiclePropertyStore::Record* VehiclePropertyStore::getRecordLocked(int32_t propId)
        REQUIRES(mLock) {
    auto RecordIt = mRecordsByPropId.find(propId);
    return RecordIt == mRecordsByPropId.end() ? nullptr : &RecordIt->second;
}

VehiclePropertyStore::RecordId VehiclePropertyStore::getRecordIdLocked(
        const VehiclePropValue& propValue, const VehiclePropertyStore::Record& record) const
        REQUIRES(mLock) {
    VehiclePropertyStore::RecordId recId{
            .area = isGlobalProp(propValue.prop) ? 0 : propValue.areaId, .token = 0};

    if (record.tokenFunction != nullptr) {
        recId.token = record.tokenFunction(propValue);
    }
    return recId;
}

VhalResult<VehiclePropValuePool::RecyclableType> VehiclePropertyStore::readValueLocked(
        const RecordId& recId, const Record& record) const REQUIRES(mLock) {
    if (auto it = record.values.find(recId); it != record.values.end()) {
        return mValuePool->obtain(*(it->second));
    }
    return StatusError(StatusCode::NOT_AVAILABLE)
           << "Record ID: " << recId.toString() << " is not found";
}

void VehiclePropertyStore::registerProperty(const VehiclePropConfig& config,
                                            VehiclePropertyStore::TokenFunction tokenFunc) {
    std::scoped_lock<std::mutex> g(mLock);

    mRecordsByPropId[config.prop] = Record{
            .propConfig = config,
            .tokenFunction = tokenFunc,
    };
}

VhalResult<void> VehiclePropertyStore::writeValue(VehiclePropValuePool::RecyclableType propValue,
                                                  bool updateStatus,
                                                  VehiclePropertyStore::EventMode eventMode) {
    std::scoped_lock<std::mutex> g(mLock);

    int32_t propId = propValue->prop;

    VehiclePropertyStore::Record* record = getRecordLocked(propId);
    if (record == nullptr) {
        return StatusError(StatusCode::INVALID_ARG) << "property: " << propId << " not registered";
    }

    if (!isGlobalProp(propId) && getAreaConfig(*propValue, record->propConfig) == nullptr) {
        return StatusError(StatusCode::INVALID_ARG)
               << "no config for property: " << propId << " area: " << propValue->areaId;
    }

    VehiclePropertyStore::RecordId recId = getRecordIdLocked(*propValue, *record);
    bool valueUpdated = true;
    if (auto it = record->values.find(recId); it != record->values.end()) {
        const VehiclePropValue* valueToUpdate = it->second.get();
        int64_t oldTimestamp = valueToUpdate->timestamp;
        VehiclePropertyStatus oldStatus = valueToUpdate->status;
        // propValue is outdated and drops it.
        if (oldTimestamp > propValue->timestamp) {
            return StatusError(StatusCode::INVALID_ARG)
                   << "outdated timestamp: " << propValue->timestamp;
        }
        if (!updateStatus) {
            propValue->status = oldStatus;
        }

        valueUpdated = (valueToUpdate->value != propValue->value ||
                        valueToUpdate->status != propValue->status ||
                        valueToUpdate->prop != propValue->prop ||
                        valueToUpdate->areaId != propValue->areaId);
    } else if (!updateStatus) {
        propValue->status = VehiclePropertyStatus::AVAILABLE;
    }

    record->values[recId] = std::move(propValue);

    if (eventMode == EventMode::NEVER) {
        return {};
    }

    if ((eventMode == EventMode::ALWAYS || valueUpdated) && mOnValueChangeCallback != nullptr) {
        mOnValueChangeCallback(*(record->values[recId]));
    }
    return {};
}

void VehiclePropertyStore::removeValue(const VehiclePropValue& propValue) {
    std::scoped_lock<std::mutex> g(mLock);

    VehiclePropertyStore::Record* record = getRecordLocked(propValue.prop);
    if (record == nullptr) {
        return;
    }

    VehiclePropertyStore::RecordId recId = getRecordIdLocked(propValue, *record);
    if (auto it = record->values.find(recId); it != record->values.end()) {
        record->values.erase(it);
    }
}

void VehiclePropertyStore::removeValuesForProperty(int32_t propId) {
    std::scoped_lock<std::mutex> g(mLock);

    VehiclePropertyStore::Record* record = getRecordLocked(propId);
    if (record == nullptr) {
        return;
    }

    record->values.clear();
}

std::vector<VehiclePropValuePool::RecyclableType> VehiclePropertyStore::readAllValues() const {
    std::scoped_lock<std::mutex> g(mLock);

    std::vector<VehiclePropValuePool::RecyclableType> allValues;

    for (auto const& [_, record] : mRecordsByPropId) {
        for (auto const& [_, value] : record.values) {
            allValues.push_back(std::move(mValuePool->obtain(*value)));
        }
    }

    return allValues;
}

VehiclePropertyStore::ValuesResultType VehiclePropertyStore::readValuesForProperty(
        int32_t propId) const {
    std::scoped_lock<std::mutex> g(mLock);

    std::vector<VehiclePropValuePool::RecyclableType> values;

    const VehiclePropertyStore::Record* record = getRecordLocked(propId);
    if (record == nullptr) {
        return StatusError(StatusCode::INVALID_ARG) << "property: " << propId << " not registered";
    }

    for (auto const& [_, value] : record->values) {
        values.push_back(std::move(mValuePool->obtain(*value)));
    }
    return values;
}

VehiclePropertyStore::ValueResultType VehiclePropertyStore::readValue(
        const VehiclePropValue& propValue) const {
    std::scoped_lock<std::mutex> g(mLock);

    int32_t propId = propValue.prop;
    const VehiclePropertyStore::Record* record = getRecordLocked(propId);
    if (record == nullptr) {
        return StatusError(StatusCode::INVALID_ARG) << "property: " << propId << " not registered";
    }

    VehiclePropertyStore::RecordId recId = getRecordIdLocked(propValue, *record);
    return readValueLocked(recId, *record);
}

VehiclePropertyStore::ValueResultType VehiclePropertyStore::readValue(int32_t propId,
                                                                      int32_t areaId,
                                                                      int64_t token) const {
    std::scoped_lock<std::mutex> g(mLock);

    const VehiclePropertyStore::Record* record = getRecordLocked(propId);
    if (record == nullptr) {
        return StatusError(StatusCode::INVALID_ARG) << "property: " << propId << " not registered";
    }

    VehiclePropertyStore::RecordId recId{.area = isGlobalProp(propId) ? 0 : areaId, .token = token};
    return readValueLocked(recId, *record);
}

std::vector<VehiclePropConfig> VehiclePropertyStore::getAllConfigs() const {
    std::scoped_lock<std::mutex> g(mLock);

    std::vector<VehiclePropConfig> configs;
    configs.reserve(mRecordsByPropId.size());
    for (auto& [_, config] : mRecordsByPropId) {
        configs.push_back(config.propConfig);
    }
    return configs;
}

VhalResult<const VehiclePropConfig*> VehiclePropertyStore::getConfig(int32_t propId) const {
    std::scoped_lock<std::mutex> g(mLock);

    const VehiclePropertyStore::Record* record = getRecordLocked(propId);
    if (record == nullptr) {
        return StatusError(StatusCode::INVALID_ARG) << "property: " << propId << " not registered";
    }

    return &record->propConfig;
}

void VehiclePropertyStore::setOnValueChangeCallback(
        const VehiclePropertyStore::OnValueChangeCallback& callback) {
    std::scoped_lock<std::mutex> g(mLock);

    mOnValueChangeCallback = callback;
}

}  // namespace vehicle
}  // namespace automotive
}  // namespace hardware
}  // namespace android