/*
 * Copyright (C) 2015 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_NDEBUG 0
#define LOG_TAG "ACameraManager"

#include <memory>
#include "ACameraManager.h"
#include "ACameraMetadata.h"
#include "ACameraDevice.h"
#include <utils/Vector.h>
#include <cutils/properties.h>
#include <stdlib.h>
#include <camera/CameraUtils.h>
#include <camera/StringUtils.h>
#include <camera/VendorTagDescriptor.h>

using namespace android::acam;

namespace android {
namespace acam {
// Static member definitions
const char* CameraManagerGlobal::kCameraIdKey   = "CameraId";
const char* CameraManagerGlobal::kPhysicalCameraIdKey   = "PhysicalCameraId";
const char* CameraManagerGlobal::kCallbackFpKey = "CallbackFp";
const char* CameraManagerGlobal::kContextKey    = "CallbackContext";
const nsecs_t CameraManagerGlobal::kCallbackDrainTimeout = 5000000; // 5 ms
Mutex                CameraManagerGlobal::sLock;
wp<CameraManagerGlobal> CameraManagerGlobal::sInstance = nullptr;

sp<CameraManagerGlobal> CameraManagerGlobal::getInstance() {
    Mutex::Autolock _l(sLock);
    sp<CameraManagerGlobal> instance = sInstance.promote();
    if (instance == nullptr) {
        instance = new CameraManagerGlobal();
        sInstance = instance;
    }
    return instance;
}

CameraManagerGlobal::~CameraManagerGlobal() {
    // clear sInstance so next getInstance call knows to create a new one
    Mutex::Autolock _sl(sLock);
    sInstance = nullptr;
    Mutex::Autolock _l(mLock);
    if (mCameraService != nullptr) {
        IInterface::asBinder(mCameraService)->unlinkToDeath(mDeathNotifier);
        mCameraService->removeListener(mCameraServiceListener);
    }
    mDeathNotifier.clear();
    if (mCbLooper != nullptr) {
        mCbLooper->unregisterHandler(mHandler->id());
        mCbLooper->stop();
    }
    mCbLooper.clear();
    mHandler.clear();
    mCameraServiceListener.clear();
    mCameraService.clear();
}

sp<hardware::ICameraService> CameraManagerGlobal::getCameraService() {
    Mutex::Autolock _l(mLock);
    return getCameraServiceLocked();
}

sp<hardware::ICameraService> CameraManagerGlobal::getCameraServiceLocked() {
    if (mCameraService.get() == nullptr) {
        if (CameraUtils::isCameraServiceDisabled()) {
            return mCameraService;
        }

        sp<IServiceManager> sm = defaultServiceManager();
        sp<IBinder> binder;
        do {
            binder = sm->getService(toString16(kCameraServiceName));
            if (binder != nullptr) {
                break;
            }
            ALOGW("CameraService not published, waiting...");
            usleep(kCameraServicePollDelay);
        } while(true);
        if (mDeathNotifier == nullptr) {
            mDeathNotifier = new DeathNotifier(this);
        }
        binder->linkToDeath(mDeathNotifier);
        mCameraService = interface_cast<hardware::ICameraService>(binder);

        // Setup looper thread to perfrom availiability callbacks
        if (mCbLooper == nullptr) {
            mCbLooper = new ALooper;
            mCbLooper->setName("C2N-mgr-looper");
            status_t err = mCbLooper->start(
                    /*runOnCallingThread*/false,
                    /*canCallJava*/       true,
                    PRIORITY_DEFAULT);
            if (err != OK) {
                ALOGE("%s: Unable to start camera service listener looper: %s (%d)",
                        __FUNCTION__, strerror(-err), err);
                mCbLooper.clear();
                return nullptr;
            }
            if (mHandler == nullptr) {
                mHandler = new CallbackHandler(this);
            }
            mCbLooper->registerHandler(mHandler);
        }

        // register ICameraServiceListener
        if (mCameraServiceListener == nullptr) {
            mCameraServiceListener = new CameraServiceListener(this);
        }
        std::vector<hardware::CameraStatus> cameraStatuses{};
        mCameraService->addListener(mCameraServiceListener, &cameraStatuses);
        for (auto& c : cameraStatuses) {
            onStatusChangedLocked(c.status, c.cameraId);

            for (auto& unavailablePhysicalId : c.unavailablePhysicalIds) {
                onStatusChangedLocked(hardware::ICameraServiceListener::STATUS_NOT_PRESENT,
                        c.cameraId, unavailablePhysicalId);
            }
        }

        // setup vendor tags
        sp<VendorTagDescriptor> desc = new VendorTagDescriptor();
        binder::Status ret = mCameraService->getCameraVendorTagDescriptor(/*out*/desc.get());

        if (ret.isOk()) {
            if (0 < desc->getTagCount()) {
                status_t err = VendorTagDescriptor::setAsGlobalVendorTagDescriptor(desc);
                if (err != OK) {
                    ALOGE("%s: Failed to set vendor tag descriptors, received error %s (%d)",
                            __FUNCTION__, strerror(-err), err);
                }
            } else {
                sp<VendorTagDescriptorCache> cache =
                        new VendorTagDescriptorCache();
                binder::Status res =
                        mCameraService->getCameraVendorTagCache(
                                /*out*/cache.get());
                if (res.serviceSpecificErrorCode() ==
                        hardware::ICameraService::ERROR_DISCONNECTED) {
                    // No camera module available, not an error on devices with no cameras
                    VendorTagDescriptorCache::clearGlobalVendorTagCache();
                } else if (res.isOk()) {
                    status_t err =
                            VendorTagDescriptorCache::setAsGlobalVendorTagCache(
                                    cache);
                    if (err != OK) {
                        ALOGE("%s: Failed to set vendor tag cache,"
                                "received error %s (%d)", __FUNCTION__,
                                strerror(-err), err);
                    }
                } else {
                    VendorTagDescriptorCache::clearGlobalVendorTagCache();
                    ALOGE("%s: Failed to setup vendor tag cache: %s",
                            __FUNCTION__, res.toString8().c_str());
                }
            }
        } else if (ret.serviceSpecificErrorCode() ==
                hardware::ICameraService::ERROR_DEPRECATED_HAL) {
            ALOGW("%s: Camera HAL too old; does not support vendor tags",
                    __FUNCTION__);
            VendorTagDescriptor::clearGlobalVendorTagDescriptor();
        } else {
            ALOGE("%s: Failed to get vendor tag descriptors: %s",
                    __FUNCTION__, ret.toString8().c_str());
        }
    }
    ALOGE_IF(mCameraService == nullptr, "no CameraService!?");
    return mCameraService;
}

void CameraManagerGlobal::DeathNotifier::binderDied(const wp<IBinder>&)
{
    ALOGE("Camera service binderDied!");
    sp<CameraManagerGlobal> cm = mCameraManager.promote();
    if (cm != nullptr) {
        AutoMutex lock(cm->mLock);
        std::vector<std::string> cameraIdList;
        for (auto& pair : cm->mDeviceStatusMap) {
            cameraIdList.push_back(pair.first);
        }

        for (const std::string& cameraId : cameraIdList) {
            cm->onStatusChangedLocked(
                    CameraServiceListener::STATUS_NOT_PRESENT, cameraId);
        }
        cm->mCameraService.clear();
        // TODO: consider adding re-connect call here?
    }
}

void CameraManagerGlobal::registerExtendedAvailabilityCallback(
        const ACameraManager_ExtendedAvailabilityCallbacks *callback) {
    return registerAvailCallback<ACameraManager_ExtendedAvailabilityCallbacks>(callback);
}

void CameraManagerGlobal::unregisterExtendedAvailabilityCallback(
        const ACameraManager_ExtendedAvailabilityCallbacks *callback) {
    Mutex::Autolock _l(mLock);

    drainPendingCallbacksLocked();

    Callback cb(callback);
    mCallbacks.erase(cb);
}

void CameraManagerGlobal::registerAvailabilityCallback(
        const ACameraManager_AvailabilityCallbacks *callback) {
    return registerAvailCallback<ACameraManager_AvailabilityCallbacks>(callback);
}

void CameraManagerGlobal::unregisterAvailabilityCallback(
        const ACameraManager_AvailabilityCallbacks *callback) {
    Mutex::Autolock _l(mLock);

    drainPendingCallbacksLocked();

    Callback cb(callback);
    mCallbacks.erase(cb);
}

void CameraManagerGlobal::onCallbackCalled() {
    Mutex::Autolock _l(mLock);
    if (mPendingCallbackCnt > 0) {
        mPendingCallbackCnt--;
    }
    mCallbacksCond.signal();
}

void CameraManagerGlobal::drainPendingCallbacksLocked() {
    while (mPendingCallbackCnt > 0) {
        auto res = mCallbacksCond.waitRelative(mLock, kCallbackDrainTimeout);
        if (res != NO_ERROR) {
            ALOGE("%s: Error waiting to drain callbacks: %s(%d)",
                    __FUNCTION__, strerror(-res), res);
            break;
        }
    }
}

template<class T>
void CameraManagerGlobal::registerAvailCallback(const T *callback) {
    Mutex::Autolock _l(mLock);
    getCameraServiceLocked();
    Callback cb(callback);
    auto pair = mCallbacks.insert(cb);
    // Send initial callbacks if callback is newly registered
    if (pair.second) {
        for (auto& pair : mDeviceStatusMap) {
            const std::string& cameraId = pair.first;
            int32_t status = pair.second.getStatus();
            // Don't send initial callbacks for camera ids which don't support
            // camera2
            if (!pair.second.supportsHAL3) {
                continue;
            }

            // Camera available/unavailable callback
            sp<AMessage> msg = new AMessage(kWhatSendSingleCallback, mHandler);
            ACameraManager_AvailabilityCallback cbFunc = isStatusAvailable(status) ?
                    cb.mAvailable : cb.mUnavailable;
            msg->setPointer(kCallbackFpKey, (void *) cbFunc);
            msg->setPointer(kContextKey, cb.mContext);
            msg->setString(kCameraIdKey, AString(cameraId.c_str()));
            mPendingCallbackCnt++;
            msg->post();

            // Physical camera unavailable callback
            std::set<std::string> unavailablePhysicalCameras =
                    pair.second.getUnavailablePhysicalIds();
            for (const auto& physicalCameraId : unavailablePhysicalCameras) {
                sp<AMessage> msg = new AMessage(kWhatSendSinglePhysicalCameraCallback, mHandler);
                ACameraManager_PhysicalCameraAvailabilityCallback cbFunc =
                        cb.mPhysicalCamUnavailable;
                msg->setPointer(kCallbackFpKey, (void *) cbFunc);
                msg->setPointer(kContextKey, cb.mContext);
                msg->setString(kCameraIdKey, AString(cameraId.c_str()));
                msg->setString(kPhysicalCameraIdKey, AString(physicalCameraId.c_str()));
                mPendingCallbackCnt++;
                msg->post();
            }
        }
    }
}

bool CameraManagerGlobal::supportsCamera2ApiLocked(const std::string &cameraId) {
    bool camera2Support = false;
    auto cs = getCameraServiceLocked();
    binder::Status serviceRet =
        cs->supportsCameraApi(cameraId,
                hardware::ICameraService::API_VERSION_2, &camera2Support);
    if (!serviceRet.isOk()) {
        ALOGE("%s: supportsCameraApi2Locked() call failed for cameraId  %s",
                __FUNCTION__, cameraId.c_str());
        return false;
    }
    return camera2Support;
}

void CameraManagerGlobal::getCameraIdList(std::vector<std::string>* cameraIds) {
    // Ensure that we have initialized/refreshed the list of available devices
    Mutex::Autolock _l(mLock);
    // Needed to make sure we're connected to cameraservice
    getCameraServiceLocked();
    for(auto& deviceStatus : mDeviceStatusMap) {
        int32_t status = deviceStatus.second.getStatus();
        if (status == hardware::ICameraServiceListener::STATUS_NOT_PRESENT ||
                status == hardware::ICameraServiceListener::STATUS_ENUMERATING) {
            continue;
        }
        if (!deviceStatus.second.supportsHAL3) {
            continue;
        }
        cameraIds->push_back(deviceStatus.first);
    }
}

bool CameraManagerGlobal::validStatus(int32_t status) {
    switch (status) {
        case hardware::ICameraServiceListener::STATUS_NOT_PRESENT:
        case hardware::ICameraServiceListener::STATUS_PRESENT:
        case hardware::ICameraServiceListener::STATUS_ENUMERATING:
        case hardware::ICameraServiceListener::STATUS_NOT_AVAILABLE:
            return true;
        default:
            return false;
    }
}

bool CameraManagerGlobal::isStatusAvailable(int32_t status) {
    switch (status) {
        case hardware::ICameraServiceListener::STATUS_PRESENT:
            return true;
        default:
            return false;
    }
}

void CameraManagerGlobal::CallbackHandler::onMessageReceived(
      const sp<AMessage> &msg) {
    onMessageReceivedInternal(msg);
    if (msg->what() == kWhatSendSingleCallback ||
            msg->what() == kWhatSendSingleAccessCallback ||
            msg->what() == kWhatSendSinglePhysicalCameraCallback) {
        notifyParent();
    }
}

void CameraManagerGlobal::CallbackHandler::onMessageReceivedInternal(
        const sp<AMessage> &msg) {
    switch (msg->what()) {
        case kWhatSendSingleCallback:
        {
            ACameraManager_AvailabilityCallback cb;
            void* context;
            AString cameraId;
            bool found = msg->findPointer(kCallbackFpKey, (void**) &cb);
            if (!found) {
                ALOGE("%s: Cannot find camera callback fp!", __FUNCTION__);
                return;
            }
            found = msg->findPointer(kContextKey, &context);
            if (!found) {
                ALOGE("%s: Cannot find callback context!", __FUNCTION__);
                return;
            }
            found = msg->findString(kCameraIdKey, &cameraId);
            if (!found) {
                ALOGE("%s: Cannot find camera ID!", __FUNCTION__);
                return;
            }
            (*cb)(context, cameraId.c_str());
            break;
        }
        case kWhatSendSingleAccessCallback:
        {
            ACameraManager_AccessPrioritiesChangedCallback cb;
            void* context;
            AString cameraId;
            bool found = msg->findPointer(kCallbackFpKey, (void**) &cb);
            if (!found) {
                ALOGE("%s: Cannot find camera callback fp!", __FUNCTION__);
                return;
            }
            found = msg->findPointer(kContextKey, &context);
            if (!found) {
                ALOGE("%s: Cannot find callback context!", __FUNCTION__);
                return;
            }
            (*cb)(context);
            break;
        }
        case kWhatSendSinglePhysicalCameraCallback:
        {
            ACameraManager_PhysicalCameraAvailabilityCallback cb;
            void* context;
            AString cameraId;
            AString physicalCameraId;
            bool found = msg->findPointer(kCallbackFpKey, (void**) &cb);
            if (!found) {
                ALOGE("%s: Cannot find camera callback fp!", __FUNCTION__);
                return;
            }
            if (cb == nullptr) {
                // Physical camera callback is null
                return;
            }
            found = msg->findPointer(kContextKey, &context);
            if (!found) {
                ALOGE("%s: Cannot find callback context!", __FUNCTION__);
                return;
            }
            found = msg->findString(kCameraIdKey, &cameraId);
            if (!found) {
                ALOGE("%s: Cannot find camera ID!", __FUNCTION__);
                return;
            }
            found = msg->findString(kPhysicalCameraIdKey, &physicalCameraId);
            if (!found) {
                ALOGE("%s: Cannot find physical camera ID!", __FUNCTION__);
                return;
            }
            (*cb)(context, cameraId.c_str(), physicalCameraId.c_str());
            break;
        }
        default:
            ALOGE("%s: unknown message type %d", __FUNCTION__, msg->what());
            break;
    }
}

void CameraManagerGlobal::CallbackHandler::notifyParent() {
    sp<CameraManagerGlobal> parent = mParent.promote();
    if (parent != nullptr) {
        parent->onCallbackCalled();
    }
}

binder::Status CameraManagerGlobal::CameraServiceListener::onCameraAccessPrioritiesChanged() {
    sp<CameraManagerGlobal> cm = mCameraManager.promote();
    if (cm != nullptr) {
        cm->onCameraAccessPrioritiesChanged();
    } else {
        ALOGE("Cannot deliver camera access priority callback. Global camera manager died");
    }
    return binder::Status::ok();
}

binder::Status CameraManagerGlobal::CameraServiceListener::onStatusChanged(
        int32_t status, const std::string& cameraId) {
    sp<CameraManagerGlobal> cm = mCameraManager.promote();
    if (cm != nullptr) {
        cm->onStatusChanged(status, cameraId);
    } else {
        ALOGE("Cannot deliver status change. Global camera manager died");
    }
    return binder::Status::ok();
}

binder::Status CameraManagerGlobal::CameraServiceListener::onPhysicalCameraStatusChanged(
        int32_t status, const std::string& cameraId, const std::string& physicalCameraId) {
    sp<CameraManagerGlobal> cm = mCameraManager.promote();
    if (cm != nullptr) {
        cm->onStatusChanged(status, cameraId, physicalCameraId);
    } else {
        ALOGE("Cannot deliver physical camera status change. Global camera manager died");
    }
    return binder::Status::ok();
}

void CameraManagerGlobal::onCameraAccessPrioritiesChanged() {
    Mutex::Autolock _l(mLock);
    for (auto cb : mCallbacks) {
        sp<AMessage> msg = new AMessage(kWhatSendSingleAccessCallback, mHandler);
        ACameraManager_AccessPrioritiesChangedCallback cbFp = cb.mAccessPriorityChanged;
        if (cbFp != nullptr) {
            msg->setPointer(kCallbackFpKey, (void *) cbFp);
            msg->setPointer(kContextKey, cb.mContext);
            mPendingCallbackCnt++;
            msg->post();
        }
    }
}

void CameraManagerGlobal::onStatusChanged(
        int32_t status, const std::string& cameraId) {
    Mutex::Autolock _l(mLock);
    onStatusChangedLocked(status, cameraId);
}

void CameraManagerGlobal::onStatusChangedLocked(
        int32_t status, const std::string& cameraId) {
    if (!validStatus(status)) {
        ALOGE("%s: Invalid status %d", __FUNCTION__, status);
        return;
    }

    bool firstStatus = (mDeviceStatusMap.count(cameraId) == 0);
    int32_t oldStatus = firstStatus ?
            status : // first status
            mDeviceStatusMap[cameraId].getStatus();

    if (!firstStatus &&
            isStatusAvailable(status) == isStatusAvailable(oldStatus)) {
        // No status update. No need to send callback
        return;
    }

    bool supportsHAL3 = supportsCamera2ApiLocked(cameraId);
    if (firstStatus) {
        mDeviceStatusMap.emplace(std::piecewise_construct,
                std::forward_as_tuple(cameraId),
                std::forward_as_tuple(status, supportsHAL3));
    } else {
        mDeviceStatusMap[cameraId].updateStatus(status);
    }
    // Iterate through all registered callbacks
    if (supportsHAL3) {
        for (auto cb : mCallbacks) {
            sp<AMessage> msg = new AMessage(kWhatSendSingleCallback, mHandler);
            ACameraManager_AvailabilityCallback cbFp = isStatusAvailable(status) ?
                    cb.mAvailable : cb.mUnavailable;
            msg->setPointer(kCallbackFpKey, (void *) cbFp);
            msg->setPointer(kContextKey, cb.mContext);
            msg->setString(kCameraIdKey, AString(cameraId.c_str()));
            mPendingCallbackCnt++;
            msg->post();
        }
    }
    if (status == hardware::ICameraServiceListener::STATUS_NOT_PRESENT) {
        mDeviceStatusMap.erase(cameraId);
    }
}

void CameraManagerGlobal::onStatusChanged(
        int32_t status, const std::string& cameraId, const std::string& physicalCameraId) {
    Mutex::Autolock _l(mLock);
    onStatusChangedLocked(status, cameraId, physicalCameraId);
}

void CameraManagerGlobal::onStatusChangedLocked(
        int32_t status, const std::string& cameraId, const std::string& physicalCameraId) {
    if (!validStatus(status)) {
        ALOGE("%s: Invalid status %d", __FUNCTION__, status);
        return;
    }

    auto logicalStatus = mDeviceStatusMap.find(cameraId);
    if (logicalStatus == mDeviceStatusMap.end()) {
        ALOGE("%s: Physical camera id %s status change on a non-present id %s",
                __FUNCTION__, physicalCameraId.c_str(), cameraId.c_str());
        return;
    }
    int32_t logicalCamStatus = mDeviceStatusMap[cameraId].getStatus();
    if (logicalCamStatus != hardware::ICameraServiceListener::STATUS_PRESENT &&
            logicalCamStatus != hardware::ICameraServiceListener::STATUS_NOT_AVAILABLE) {
        ALOGE("%s: Physical camera id %s status %d change for an invalid logical camera state %d",
                __FUNCTION__, physicalCameraId.c_str(), status, logicalCamStatus);
        return;
    }

    bool supportsHAL3 = supportsCamera2ApiLocked(cameraId);

    bool updated = false;
    if (status == hardware::ICameraServiceListener::STATUS_PRESENT) {
        updated = mDeviceStatusMap[cameraId].removeUnavailablePhysicalId(physicalCameraId);
    } else {
        updated = mDeviceStatusMap[cameraId].addUnavailablePhysicalId(physicalCameraId);
    }

    // Iterate through all registered callbacks
    if (supportsHAL3 && updated) {
        for (auto cb : mCallbacks) {
            sp<AMessage> msg = new AMessage(kWhatSendSinglePhysicalCameraCallback, mHandler);
            ACameraManager_PhysicalCameraAvailabilityCallback cbFp = isStatusAvailable(status) ?
                    cb.mPhysicalCamAvailable : cb.mPhysicalCamUnavailable;
            msg->setPointer(kCallbackFpKey, (void *) cbFp);
            msg->setPointer(kContextKey, cb.mContext);
            msg->setString(kCameraIdKey, AString(cameraId.c_str()));
            msg->setString(kPhysicalCameraIdKey, AString(physicalCameraId.c_str()));
            mPendingCallbackCnt++;
            msg->post();
        }
    }
}

int32_t CameraManagerGlobal::StatusAndHAL3Support::getStatus() {
    std::lock_guard<std::mutex> lock(mLock);
    return status;
}

void CameraManagerGlobal::StatusAndHAL3Support::updateStatus(int32_t newStatus) {
    std::lock_guard<std::mutex> lock(mLock);
    status = newStatus;
}

bool CameraManagerGlobal::StatusAndHAL3Support::addUnavailablePhysicalId(
        const std::string& physicalCameraId) {
    std::lock_guard<std::mutex> lock(mLock);
    auto result = unavailablePhysicalIds.insert(physicalCameraId);
    return result.second;
}

bool CameraManagerGlobal::StatusAndHAL3Support::removeUnavailablePhysicalId(
        const std::string& physicalCameraId) {
    std::lock_guard<std::mutex> lock(mLock);
    auto count = unavailablePhysicalIds.erase(physicalCameraId);
    return count > 0;
}

std::set<std::string> CameraManagerGlobal::StatusAndHAL3Support::getUnavailablePhysicalIds() {
    std::lock_guard<std::mutex> lock(mLock);
    return unavailablePhysicalIds;
}

} // namespace acam
} // namespace android

/**
 * ACameraManger Implementation
 */
camera_status_t
ACameraManager::getCameraIdList(ACameraIdList** cameraIdList) {
    Mutex::Autolock _l(mLock);

    std::vector<std::string> idList;
    CameraManagerGlobal::getInstance()->getCameraIdList(&idList);

    int numCameras = idList.size();
    ACameraIdList *out = new ACameraIdList;
    if (!out) {
        ALOGE("Allocate memory for ACameraIdList failed!");
        return ACAMERA_ERROR_NOT_ENOUGH_MEMORY;
    }
    out->numCameras = numCameras;
    out->cameraIds = new const char*[numCameras];
    if (!out->cameraIds) {
        ALOGE("Allocate memory for ACameraIdList failed!");
        deleteCameraIdList(out);
        return ACAMERA_ERROR_NOT_ENOUGH_MEMORY;
    }
    for (int i = 0; i < numCameras; i++) {
        const char* src = idList[i].c_str();
        size_t dstSize = strlen(src) + 1;
        char* dst = new char[dstSize];
        if (!dst) {
            ALOGE("Allocate memory for ACameraIdList failed!");
            deleteCameraIdList(out);
            return ACAMERA_ERROR_NOT_ENOUGH_MEMORY;
        }
        strlcpy(dst, src, dstSize);
        out->cameraIds[i] = dst;
    }
    *cameraIdList = out;
    return ACAMERA_OK;
}

void
ACameraManager::deleteCameraIdList(ACameraIdList* cameraIdList) {
    if (cameraIdList != nullptr) {
        if (cameraIdList->cameraIds != nullptr) {
            for (int i = 0; i < cameraIdList->numCameras; i ++) {
                if (cameraIdList->cameraIds[i] != nullptr) {
                    delete[] cameraIdList->cameraIds[i];
                }
            }
            delete[] cameraIdList->cameraIds;
        }
        delete cameraIdList;
    }
}

camera_status_t ACameraManager::getCameraCharacteristics(
        const char* cameraIdStr, sp<ACameraMetadata>* characteristics) {
    Mutex::Autolock _l(mLock);

    sp<hardware::ICameraService> cs = CameraManagerGlobal::getInstance()->getCameraService();
    if (cs == nullptr) {
        ALOGE("%s: Cannot reach camera service!", __FUNCTION__);
        return ACAMERA_ERROR_CAMERA_DISCONNECTED;
    }

    CameraMetadata rawMetadata;
    int targetSdkVersion = android_get_application_target_sdk_version();
    binder::Status serviceRet = cs->getCameraCharacteristics(cameraIdStr,
            targetSdkVersion, /*overrideToPortrait*/false, &rawMetadata);
    if (!serviceRet.isOk()) {
        switch(serviceRet.serviceSpecificErrorCode()) {
            case hardware::ICameraService::ERROR_DISCONNECTED:
                ALOGE("%s: Camera %s has been disconnected", __FUNCTION__, cameraIdStr);
                return ACAMERA_ERROR_CAMERA_DISCONNECTED;
            case hardware::ICameraService::ERROR_ILLEGAL_ARGUMENT:
                ALOGE("%s: Camera ID %s does not exist!", __FUNCTION__, cameraIdStr);
                return ACAMERA_ERROR_INVALID_PARAMETER;
            default:
                ALOGE("Get camera characteristics from camera service failed: %s",
                        serviceRet.toString8().c_str());
                return ACAMERA_ERROR_UNKNOWN; // should not reach here
        }
    }

    *characteristics = new ACameraMetadata(
            rawMetadata.release(), ACameraMetadata::ACM_CHARACTERISTICS);
    return ACAMERA_OK;
}

camera_status_t
ACameraManager::openCamera(
        const char* cameraId,
        ACameraDevice_StateCallbacks* callback,
        /*out*/ACameraDevice** outDevice) {
    sp<ACameraMetadata> chars;
    camera_status_t ret = getCameraCharacteristics(cameraId, &chars);
    Mutex::Autolock _l(mLock);
    if (ret != ACAMERA_OK) {
        ALOGE("%s: cannot get camera characteristics for camera %s. err %d",
                __FUNCTION__, cameraId, ret);
        return ACAMERA_ERROR_INVALID_PARAMETER;
    }

    ACameraDevice* device = new ACameraDevice(cameraId, callback, chars);

    sp<hardware::ICameraService> cs = CameraManagerGlobal::getInstance()->getCameraService();
    if (cs == nullptr) {
        ALOGE("%s: Cannot reach camera service!", __FUNCTION__);
        delete device;
        return ACAMERA_ERROR_CAMERA_DISCONNECTED;
    }

    sp<hardware::camera2::ICameraDeviceCallbacks> callbacks = device->getServiceCallback();
    sp<hardware::camera2::ICameraDeviceUser> deviceRemote;
    int targetSdkVersion = android_get_application_target_sdk_version();
    // No way to get package name from native.
    // Send a zero length package name and let camera service figure it out from UID
    binder::Status serviceRet = cs->connectDevice(
            callbacks, cameraId, "", {},
            hardware::ICameraService::USE_CALLING_UID, /*oomScoreOffset*/0,
            targetSdkVersion, /*overrideToPortrait*/false, /*out*/&deviceRemote);

    if (!serviceRet.isOk()) {
        ALOGE("%s: connect camera device failed: %s", __FUNCTION__, serviceRet.toString8().c_str());
        // Convert serviceRet to camera_status_t
        switch(serviceRet.serviceSpecificErrorCode()) {
            case hardware::ICameraService::ERROR_DISCONNECTED:
                ret = ACAMERA_ERROR_CAMERA_DISCONNECTED;
                break;
            case hardware::ICameraService::ERROR_CAMERA_IN_USE:
                ret = ACAMERA_ERROR_CAMERA_IN_USE;
                break;
            case hardware::ICameraService::ERROR_MAX_CAMERAS_IN_USE:
                ret = ACAMERA_ERROR_MAX_CAMERA_IN_USE;
                break;
            case hardware::ICameraService::ERROR_ILLEGAL_ARGUMENT:
                ret = ACAMERA_ERROR_INVALID_PARAMETER;
                break;
            case hardware::ICameraService::ERROR_DEPRECATED_HAL:
                // Should not reach here since we filtered legacy HALs earlier
                ret = ACAMERA_ERROR_INVALID_PARAMETER;
                break;
            case hardware::ICameraService::ERROR_DISABLED:
                ret = ACAMERA_ERROR_CAMERA_DISABLED;
                break;
            case hardware::ICameraService::ERROR_PERMISSION_DENIED:
                ret = ACAMERA_ERROR_PERMISSION_DENIED;
                break;
            case hardware::ICameraService::ERROR_INVALID_OPERATION:
            default:
                ret = ACAMERA_ERROR_UNKNOWN;
                break;
        }

        delete device;
        return ret;
    }
    if (deviceRemote == nullptr) {
        ALOGE("%s: connect camera device failed! remote device is null", __FUNCTION__);
        delete device;
        return ACAMERA_ERROR_CAMERA_DISCONNECTED;
    }
    device->setRemoteDevice(deviceRemote);
    *outDevice = device;
    return ACAMERA_OK;
}

ACameraManager::~ACameraManager() {

}