/*
 * Copyright 2019 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 "SuspendControlService.h"

#include <android-base/logging.h>
#include <android-base/stringprintf.h>
#include <signal.h>

#include "SystemSuspend.h"

using ::android::base::Result;
using ::android::base::StringPrintf;

namespace android {
namespace system {
namespace suspend {
namespace V1_0 {

static void register_sig_handler() {
    signal(SIGPIPE, SIG_IGN);
}

template <typename T>
binder::Status retOk(const T& value, T* ret_val) {
    *ret_val = value;
    return binder::Status::ok();
}

binder::Status SuspendControlService::registerCallback(const sp<ISuspendCallback>& callback,
                                                       bool* _aidl_return) {
    if (!callback) {
        return retOk(false, _aidl_return);
    }

    auto l = std::lock_guard(mCallbackLock);
    sp<IBinder> cb = IInterface::asBinder(callback);
    // Only remote binders can be linked to death
    if (cb->remoteBinder() != nullptr) {
        if (findCb(cb) == mCallbacks.end()) {
            auto status = cb->linkToDeath(this);
            if (status != NO_ERROR) {
                LOG(ERROR) << __func__ << " Cannot link to death: " << status;
                return retOk(false, _aidl_return);
            }
        }
    }
    mCallbacks.push_back(callback);
    return retOk(true, _aidl_return);
}

binder::Status SuspendControlService::registerWakelockCallback(
    const sp<IWakelockCallback>& callback, const std::string& name, bool* _aidl_return) {
    if (!callback || name.empty()) {
        return retOk(false, _aidl_return);
    }

    auto l = std::lock_guard(mWakelockCallbackLock);
    if (std::find_if(mWakelockCallbacks[name].begin(), mWakelockCallbacks[name].end(),
                     [&callback](const sp<IWakelockCallback>& i) {
                         return IInterface::asBinder(callback) == IInterface::asBinder(i);
                     }) != mWakelockCallbacks[name].end()) {
        LOG(ERROR) << __func__ << " Same wakelock callback has already been registered";
        return retOk(false, _aidl_return);
    }

    if (IInterface::asBinder(callback)->remoteBinder() &&
        IInterface::asBinder(callback)->linkToDeath(this) != NO_ERROR) {
        LOG(WARNING) << __func__ << " Cannot link to death";
        return retOk(false, _aidl_return);
    }
    mWakelockCallbacks[name].push_back(callback);

    return retOk(true, _aidl_return);
}

void SuspendControlService::binderDied(const wp<IBinder>& who) {
    auto l = std::lock_guard(mCallbackLock);
    mCallbacks.erase(std::remove_if(mCallbacks.begin(), mCallbacks.end(),
                                    [&who](const sp<ISuspendCallback>& i) {
                                        return who == IInterface::asBinder(i);
                                    }),
                     mCallbacks.end());

    auto lWakelock = std::lock_guard(mWakelockCallbackLock);
    // Iterate through all wakelock names as same callback can be registered with different
    // wakelocks.
    for (auto wakelockIt = mWakelockCallbacks.begin(); wakelockIt != mWakelockCallbacks.end();) {
        wakelockIt->second.erase(
            std::remove_if(
                wakelockIt->second.begin(), wakelockIt->second.end(),
                [&who](const sp<IWakelockCallback>& i) { return who == IInterface::asBinder(i); }),
            wakelockIt->second.end());
        if (wakelockIt->second.empty()) {
            wakelockIt = mWakelockCallbacks.erase(wakelockIt);
        } else {
            ++wakelockIt;
        }
    }
}

void SuspendControlService::notifyWakelock(const std::string& name, bool isAcquired) {
    // A callback could potentially modify mWakelockCallbacks (e.g., via registerCallback). That
    // must not result in a deadlock. To that end, we make a copy of the callback is an entry can be
    // found for the particular wakelock  and release mCallbackLock before calling the copied
    // callbacks.
    auto callbackLock = std::unique_lock(mWakelockCallbackLock);
    auto it = mWakelockCallbacks.find(name);
    if (it == mWakelockCallbacks.end()) {
        return;
    }
    auto callbacksCopy = it->second;
    callbackLock.unlock();

    for (const auto& callback : callbacksCopy) {
        if (isAcquired) {
            callback->notifyAcquired().isOk();  // ignore errors
        } else {
            callback->notifyReleased().isOk();  // ignore errors
        }
    }
}

void SuspendControlService::notifyWakeup(bool success, std::vector<std::string>& wakeupReasons) {
    // A callback could potentially modify mCallbacks (e.g., via registerCallback). That must not
    // result in a deadlock. To that end, we make a copy of mCallbacks and release mCallbackLock
    // before calling the copied callbacks.
    auto callbackLock = std::unique_lock(mCallbackLock);
    auto callbacksCopy = mCallbacks;
    callbackLock.unlock();

    for (const auto& callback : callbacksCopy) {
        callback->notifyWakeup(success, wakeupReasons).isOk();  // ignore errors
    }
}

void SuspendControlServiceInternal::setSuspendService(const wp<SystemSuspend>& suspend) {
    mSuspend = suspend;
}

binder::Status SuspendControlServiceInternal::enableAutosuspend(const sp<IBinder>& token,
                                                                bool* _aidl_return) {
    const auto suspendService = mSuspend.promote();
    return retOk(suspendService != nullptr && suspendService->enableAutosuspend(token),
                 _aidl_return);
}

binder::Status SuspendControlServiceInternal::forceSuspend(bool* _aidl_return) {
    const auto suspendService = mSuspend.promote();
    return retOk(suspendService != nullptr && suspendService->forceSuspend(), _aidl_return);
}

binder::Status SuspendControlServiceInternal::getSuspendStats(SuspendInfo* _aidl_return) {
    const auto suspendService = mSuspend.promote();
    if (!suspendService) {
        return binder::Status::fromExceptionCode(binder::Status::Exception::EX_NULL_POINTER,
                                                 String8("Null reference to suspendService"));
    }

    suspendService->getSuspendInfo(_aidl_return);
    return binder::Status::ok();
}

binder::Status SuspendControlServiceInternal::getWakeLockStats(
    std::vector<WakeLockInfo>* _aidl_return) {
    const auto suspendService = mSuspend.promote();
    if (!suspendService) {
        return binder::Status::fromExceptionCode(binder::Status::Exception::EX_NULL_POINTER,
                                                 String8("Null reference to suspendService"));
    }

    suspendService->updateStatsNow();
    suspendService->getStatsList().getWakeLockStats(_aidl_return);

    return binder::Status::ok();
}

binder::Status SuspendControlServiceInternal::getWakeupStats(
    std::vector<WakeupInfo>* _aidl_return) {
    const auto suspendService = mSuspend.promote();
    if (!suspendService) {
        return binder::Status::fromExceptionCode(binder::Status::Exception::EX_NULL_POINTER,
                                                 String8("Null reference to suspendService"));
    }

    suspendService->getWakeupList().getWakeupStats(_aidl_return);
    return binder::Status::ok();
}

static std::string dumpUsage() {
    return "\nUsage: adb shell dumpsys suspend_control_internal [option]\n\n"
           "   Options:\n"
           "       --wakelocks        : returns wakelock stats.\n"
           "       --wakeups          : returns wakeup stats.\n"
           "       --kernel_suspends  : returns suspend success/error stats from the kernel\n"
           "       --suspend_controls : returns suspend control stats\n"
           "       --all or -a        : returns all stats.\n"
           "       --help or -h       : prints this message.\n\n"
           "   Note: All stats are returned  if no or (an\n"
           "         invalid) option is specified.\n\n";
}

status_t SuspendControlServiceInternal::dump(int fd, const Vector<String16>& args) {
    register_sig_handler();

    const auto suspendService = mSuspend.promote();
    if (!suspendService) {
        return DEAD_OBJECT;
    }

    enum : int32_t {
        OPT_WAKELOCKS = 1 << 0,
        OPT_WAKEUPS = 1 << 1,
        OPT_KERNEL_SUSPENDS = 1 << 2,
        OPT_SUSPEND_CONTROLS = 1 << 3,
        OPT_ALL = ~0,
    };
    int opts = 0;

    if (args.empty()) {
        opts = OPT_ALL;
    } else {
        for (const auto& arg : args) {
            if (arg == String16("--wakelocks")) {
                opts |= OPT_WAKELOCKS;
            } else if (arg == String16("--wakeups")) {
                opts |= OPT_WAKEUPS;
            } else if (arg == String16("--kernel_suspends")) {
                opts |= OPT_KERNEL_SUSPENDS;
            } else if (arg == String16("--suspend_controls")) {
                opts |= OPT_SUSPEND_CONTROLS;
            } else if (arg == String16("-a") || arg == String16("--all")) {
                opts = OPT_ALL;
            } else if (arg == String16("-h") || arg == String16("--help")) {
                std::string usage = dumpUsage();
                dprintf(fd, "%s\n", usage.c_str());
                return OK;
            }
        }
    }

    if (opts & OPT_WAKELOCKS) {
        suspendService->updateStatsNow();
        std::stringstream wlStats;
        wlStats << suspendService->getStatsList();
        dprintf(fd, "\n%s\n", wlStats.str().c_str());
    }

    if (opts & OPT_WAKEUPS) {
        std::ostringstream wakeupStats;
        std::vector<WakeupInfo> wakeups;
        suspendService->getWakeupList().getWakeupStats(&wakeups);
        for (const auto& w : wakeups) {
            wakeupStats << w.toString() << std::endl;
        }
        dprintf(fd, "Wakeups:\n%s\n", wakeupStats.str().c_str());
    }

    if (opts & OPT_KERNEL_SUSPENDS) {
        Result<SuspendStats> res = suspendService->getSuspendStats();
        if (!res.ok()) {
            LOG(ERROR) << "SuspendControlService: " << res.error().message();
            return OK;
        }

        SuspendStats stats = res.value();
        // clang-format off
        std::string suspendStats = StringPrintf(
            "----- Suspend Stats -----\n"
            "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
            "%s: %d\n%s: %d\n%s: %d\n%s: %d\n%s: %d\n"
            "\nLast Failures:\n"
            "    %s: %s\n"
            "    %s: %d\n"
            "    %s: %s\n"
            "----------\n\n",

            "success", stats.success,
            "fail", stats.fail,
            "failed_freeze", stats.failedFreeze,
            "failed_prepare", stats.failedPrepare,
            "failed_suspend", stats.failedSuspend,
            "failed_suspend_late", stats.failedSuspendLate,
            "failed_suspend_noirq", stats.failedSuspendNoirq,
            "failed_resume", stats.failedResume,
            "failed_resume_early", stats.failedResumeEarly,
            "failed_resume_noirq", stats.failedResumeNoirq,
            "last_failed_dev", stats.lastFailedDev.c_str(),
            "last_failed_errno", stats.lastFailedErrno,
            "last_failed_step", stats.lastFailedStep.c_str());
        // clang-format on
        dprintf(fd, "\n%s\n", suspendStats.c_str());
    }

    if (opts & OPT_SUSPEND_CONTROLS) {
        std::ostringstream suspendInfo;
        SuspendInfo info;
        suspendService->getSuspendInfo(&info);
        suspendInfo << "suspend attempts: " << info.suspendAttemptCount << std::endl;
        suspendInfo << "failed suspends: " << info.failedSuspendCount << std::endl;
        suspendInfo << "short suspends: " << info.shortSuspendCount << std::endl;
        suspendInfo << "total suspend time: " << info.suspendTimeMillis << " ms" << std::endl;
        suspendInfo << "short suspend time: " << info.shortSuspendTimeMillis << " ms" << std::endl;
        suspendInfo << "suspend overhead: " << info.suspendOverheadTimeMillis << " ms" << std::endl;
        suspendInfo << "failed suspend overhead: " << info.failedSuspendOverheadTimeMillis << " ms"
                    << std::endl;
        suspendInfo << "new backoffs: " << info.newBackoffCount << std::endl;
        suspendInfo << "backoff continuations: " << info.backoffContinueCount << std::endl;
        suspendInfo << "total sleep time between suspends: " << info.sleepTimeMillis << " ms"
                    << std::endl;
        dprintf(fd, "Suspend Info:\n%s\n", suspendInfo.str().c_str());
    }

    return OK;
}

}  // namespace V1_0
}  // namespace suspend
}  // namespace system
}  // namespace android