/*
 * Copyright (C) 2016 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 "SensorDevice.h"
#include "SensorDirectConnection.h"
#include <android/util/ProtoOutputStream.h>
#include <frameworks/base/core/proto/android/service/sensor_service.proto.h>
#include <hardware/sensors.h>

#define UNUSED(x) (void)(x)

namespace android {

using util::ProtoOutputStream;

SensorService::SensorDirectConnection::SensorDirectConnection(const sp<SensorService>& service,
        uid_t uid, const sensors_direct_mem_t *mem, int32_t halChannelHandle,
        const String16& opPackageName)
        : mService(service), mUid(uid), mMem(*mem),
        mHalChannelHandle(halChannelHandle),
        mOpPackageName(opPackageName), mDestroyed(false) {
    mUserId = multiuser_get_user_id(mUid);
    ALOGD_IF(DEBUG_CONNECTIONS, "Created SensorDirectConnection");
}

SensorService::SensorDirectConnection::~SensorDirectConnection() {
    ALOGD_IF(DEBUG_CONNECTIONS, "~SensorDirectConnection %p", this);
    destroy();
}

void SensorService::SensorDirectConnection::destroy() {
    Mutex::Autolock _l(mDestroyLock);
    // destroy once only
    if (mDestroyed) {
        return;
    }

    stopAll();
    mService->cleanupConnection(this);
    if (mMem.handle != nullptr) {
        native_handle_close(mMem.handle);
        native_handle_delete(const_cast<struct native_handle*>(mMem.handle));
    }
    mDestroyed = true;
}

void SensorService::SensorDirectConnection::onFirstRef() {
}

void SensorService::SensorDirectConnection::dump(String8& result) const {
    Mutex::Autolock _l(mConnectionLock);
    result.appendFormat("\tPackage %s, HAL channel handle %d, total sensor activated %zu\n",
            String8(mOpPackageName).c_str(), getHalChannelHandle(), mActivated.size());
    for (auto &i : mActivated) {
        result.appendFormat("\t\tSensor %#08x, rate %d\n", i.first, i.second);
    }
}

/**
 * Dump debugging information as android.service.SensorDirectConnectionProto protobuf message using
 * ProtoOutputStream.
 *
 * See proto definition and some notes about ProtoOutputStream in
 * frameworks/base/core/proto/android/service/sensor_service.proto
 */
void SensorService::SensorDirectConnection::dump(ProtoOutputStream* proto) const {
    using namespace service::SensorDirectConnectionProto;
    Mutex::Autolock _l(mConnectionLock);
    proto->write(PACKAGE_NAME, std::string(String8(mOpPackageName).c_str()));
    proto->write(HAL_CHANNEL_HANDLE, getHalChannelHandle());
    proto->write(NUM_SENSOR_ACTIVATED, int(mActivated.size()));
    for (auto &i : mActivated) {
        uint64_t token = proto->start(SENSORS);
        proto->write(SensorProto::SENSOR, i.first);
        proto->write(SensorProto::RATE, i.second);
        proto->end(token);
    }
}

sp<BitTube> SensorService::SensorDirectConnection::getSensorChannel() const {
    return nullptr;
}

void SensorService::SensorDirectConnection::onSensorAccessChanged(bool hasAccess) {
    if (!hasAccess) {
        stopAll(true /* backupRecord */);
    } else {
        recoverAll();
    }
}

void SensorService::SensorDirectConnection::onMicSensorAccessChanged(bool isMicToggleOn) {
    if (isMicToggleOn) {
        capRates();
    } else {
        uncapRates();
    }
}

bool SensorService::SensorDirectConnection::hasSensorAccess() const {
    return mService->hasSensorAccess(mUid, mOpPackageName);
}

status_t SensorService::SensorDirectConnection::enableDisable(
        int handle, bool enabled, nsecs_t samplingPeriodNs, nsecs_t maxBatchReportLatencyNs,
        int reservedFlags) {
    // SensorDirectConnection does not support enableDisable, parameters not used
    UNUSED(handle);
    UNUSED(enabled);
    UNUSED(samplingPeriodNs);
    UNUSED(maxBatchReportLatencyNs);
    UNUSED(reservedFlags);
    return INVALID_OPERATION;
}

status_t SensorService::SensorDirectConnection::setEventRate(
        int handle, nsecs_t samplingPeriodNs) {
    // SensorDirectConnection does not support setEventRate, parameters not used
    UNUSED(handle);
    UNUSED(samplingPeriodNs);
    return INVALID_OPERATION;
}

status_t SensorService::SensorDirectConnection::flush() {
    // SensorDirectConnection does not support flush
    return INVALID_OPERATION;
}

int32_t SensorService::SensorDirectConnection::configureChannel(int handle, int rateLevel) {

    if (handle == -1 && rateLevel == SENSOR_DIRECT_RATE_STOP) {
        stopAll();
        mMicRateBackup.clear();
        return NO_ERROR;
    }

    if (!hasSensorAccess()) {
        return PERMISSION_DENIED;
    }

    sp<SensorInterface> si = mService->getSensorInterfaceFromHandle(handle);
    if (si == nullptr) {
        return NAME_NOT_FOUND;
    }

    const Sensor& s = si->getSensor();
    if (!mService->canAccessSensor(s, "config direct channel", mOpPackageName)) {
        return PERMISSION_DENIED;
    }

    if (s.getHighestDirectReportRateLevel() == 0
            || rateLevel > s.getHighestDirectReportRateLevel()
            || !s.isDirectChannelTypeSupported(mMem.type)) {
        return INVALID_OPERATION;
    }

    int requestedRateLevel = rateLevel;
    if (mService->isSensorInCappedSet(s.getType()) && rateLevel != SENSOR_DIRECT_RATE_STOP) {
        status_t err = mService->adjustRateLevelBasedOnMicAndPermission(&rateLevel, mOpPackageName);
        if (err != OK) {
            return err;
        }
    }

    struct sensors_direct_cfg_t config = {
        .rate_level = rateLevel
    };

    Mutex::Autolock _l(mConnectionLock);
    SensorDevice& dev(SensorDevice::getInstance());
    int ret = dev.configureDirectChannel(handle, getHalChannelHandle(), &config);

    if (rateLevel == SENSOR_DIRECT_RATE_STOP) {
        if (ret == NO_ERROR) {
            mActivated.erase(handle);
            mMicRateBackup.erase(handle);
        } else if (ret > 0) {
            ret = UNKNOWN_ERROR;
        }
    } else {
        if (ret > 0) {
            mActivated[handle] = rateLevel;
            if (mService->isSensorInCappedSet(s.getType())) {
                // Back up the rates that the app is allowed to have if the mic toggle is off
                // This is used in the uncapRates() function.
                if ((requestedRateLevel <= SENSOR_SERVICE_CAPPED_SAMPLING_RATE_LEVEL) ||
                    !isRateCappedBasedOnPermission()) {
                    mMicRateBackup[handle] = requestedRateLevel;
                } else {
                    mMicRateBackup[handle] = SENSOR_SERVICE_CAPPED_SAMPLING_RATE_LEVEL;
                }
            }
        }
    }

    return ret;
}

void SensorService::SensorDirectConnection::capRates() {
    Mutex::Autolock _l(mConnectionLock);
    const struct sensors_direct_cfg_t capConfig = {
        .rate_level = SENSOR_SERVICE_CAPPED_SAMPLING_RATE_LEVEL
    };

    const struct sensors_direct_cfg_t stopConfig = {
        .rate_level = SENSOR_DIRECT_RATE_STOP
    };

    // If our requests are in the backup, then we shouldn't activate sensors from here
    bool temporarilyStopped = mActivated.empty() && !mActivatedBackup.empty();
    std::unordered_map<int, int>& existingConnections =
                    (!temporarilyStopped) ? mActivated : mActivatedBackup;

    SensorDevice& dev(SensorDevice::getInstance());
    for (auto &i : existingConnections) {
        int handle = i.first;
        int rateLevel = i.second;
        sp<SensorInterface> si = mService->getSensorInterfaceFromHandle(handle);
        if (si != nullptr) {
            const Sensor& s = si->getSensor();
            if (mService->isSensorInCappedSet(s.getType()) &&
                        rateLevel > SENSOR_SERVICE_CAPPED_SAMPLING_RATE_LEVEL) {
                mMicRateBackup[handle] = rateLevel;
                // Modify the rate kept by the existing map
                existingConnections[handle] = SENSOR_SERVICE_CAPPED_SAMPLING_RATE_LEVEL;
                // Only reconfigure the channel if it's ongoing
                if (!temporarilyStopped) {
                    // Stopping before reconfiguring is the well-tested path in CTS
                    dev.configureDirectChannel(handle, getHalChannelHandle(), &stopConfig);
                    dev.configureDirectChannel(handle, getHalChannelHandle(), &capConfig);
                }
            }
        }
    }
}

void SensorService::SensorDirectConnection::uncapRates() {
    Mutex::Autolock _l(mConnectionLock);

    // If our requests are in the backup, then we shouldn't activate sensors from here
    bool temporarilyStopped = mActivated.empty() && !mActivatedBackup.empty();
    std::unordered_map<int, int>& existingConnections =
                    (!temporarilyStopped) ? mActivated : mActivatedBackup;

    const struct sensors_direct_cfg_t stopConfig = {
        .rate_level = SENSOR_DIRECT_RATE_STOP
    };
    SensorDevice& dev(SensorDevice::getInstance());
    for (auto &i : mMicRateBackup) {
        int handle = i.first;
        int rateLevel = i.second;

        const struct sensors_direct_cfg_t config = {
            .rate_level = rateLevel
        };

        // Modify the rate kept by the existing map
        existingConnections[handle] = rateLevel;

        // Only reconfigure the channel if it's ongoing
        if (!temporarilyStopped) {
            // Stopping before reconfiguring is the well-tested path in CTS
            dev.configureDirectChannel(handle, getHalChannelHandle(), &stopConfig);
            dev.configureDirectChannel(handle, getHalChannelHandle(), &config);
        }
    }
    mMicRateBackup.clear();
}

void SensorService::SensorDirectConnection::stopAll(bool backupRecord) {
    Mutex::Autolock _l(mConnectionLock);
    stopAllLocked(backupRecord);
}

void SensorService::SensorDirectConnection::stopAllLocked(bool backupRecord) {
    struct sensors_direct_cfg_t config = {
        .rate_level = SENSOR_DIRECT_RATE_STOP
    };

    SensorDevice& dev(SensorDevice::getInstance());
    for (auto &i : mActivated) {
        dev.configureDirectChannel(i.first, getHalChannelHandle(), &config);
    }

    if (backupRecord && mActivatedBackup.empty()) {
        mActivatedBackup = mActivated;
    }
    mActivated.clear();
}

void SensorService::SensorDirectConnection::recoverAll() {
    Mutex::Autolock _l(mConnectionLock);
    if (!mActivatedBackup.empty()) {
        stopAllLocked(false);

        SensorDevice& dev(SensorDevice::getInstance());

        // recover list of report from backup
        ALOG_ASSERT(mActivated.empty(),
                    "mActivated must be empty if mActivatedBackup was non-empty");
        mActivated = mActivatedBackup;
        mActivatedBackup.clear();

        // re-enable them
        for (auto &i : mActivated) {
            struct sensors_direct_cfg_t config = {
                .rate_level = i.second
            };
            dev.configureDirectChannel(i.first, getHalChannelHandle(), &config);
        }
    }
}

int32_t SensorService::SensorDirectConnection::getHalChannelHandle() const {
    return mHalChannelHandle;
}

bool SensorService::SensorDirectConnection::isEquivalent(const sensors_direct_mem_t *mem) const {
    bool ret = false;

    if (mMem.type == mem->type) {
        switch (mMem.type) {
            case SENSOR_DIRECT_MEM_TYPE_ASHMEM: {
                // there is no known method to test if two ashmem fds are equivalent besides
                // trivially comparing the fd values (ino number from fstat() are always the
                // same, pointing to "/dev/ashmem").
                int fd1 = mMem.handle->data[0];
                int fd2 = mem->handle->data[0];
                ret = (fd1 == fd2);
                break;
            }
            case SENSOR_DIRECT_MEM_TYPE_GRALLOC:
                // there is no known method to test if two gralloc handle are equivalent
                ret = false;
                break;
            default:
                // should never happen
                ALOGE("Unexpected mem type %d", mMem.type);
                ret = true;
                break;
        }
    }
    return ret;
}

} // namespace android