/*
 * Copyright (c) 2024 Huawei Device Co., Ltd.
 * 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 MEDIA_TASK_THREAD
#define HST_LOG_TAG "Task"
#include "osal/task/task.h"
#include "osal/task/taskInner.h"
#include "osal/task/thread.h"
#include "osal/task/pipeline_threadpool.h"
#include "osal/utils/util.h"
#include "cpp_ext/memory_ext.h"
#include "common/log.h"

#include <mutex>

namespace {
constexpr OHOS::HiviewDFX::HiLogLabel LABEL = { LOG_CORE, LOG_DOMAIN_FOUNDATION, "TaskInner" };
}

namespace OHOS {
namespace Media {
namespace {
    constexpr int64_t INVALID_DELAY_TIME_US = 10000000; // 10s
}
static std::atomic<uint16_t> singletonTaskId = 0;

void TaskInner::SleepInTask(unsigned ms)
{
    OSAL::SleepFor(ms);
}

static int64_t GetNowUs()
{
    auto now = std::chrono::steady_clock::now();
    return std::chrono::duration_cast<std::chrono::microseconds>(now.time_since_epoch()).count();
}

TaskInner::TaskInner(const std::string& name, const std::string& groupId, TaskType type, TaskPriority priority,
    bool singleLoop)
    : name_(std::move(name)), runningState_(RunningState::PAUSED), singleLoop_(singleLoop)
{
    MEDIA_LOG_I_T(">> " PUBLIC_LOG_S " groupId:" PUBLIC_LOG_S " type:%{public}d ctor",
        name_.c_str(), groupId.c_str(), type);
    if (type == TaskType::SINGLETON) {
        std::string newName = name_ + std::to_string(++singletonTaskId);
        pipelineThread_ = PipeLineThreadPool::GetInstance().FindThread(newName, type, priority);
    } else {
        pipelineThread_ = PipeLineThreadPool::GetInstance().FindThread(groupId, type, priority);
    }
}

void TaskInner::Init()
{
    MEDIA_LOG_I_T(">> " PUBLIC_LOG_S " Init", name_.c_str());
    pipelineThread_->AddTask(shared_from_this());
}

void TaskInner::DeInit()
{
    MEDIA_LOG_I_T(PUBLIC_LOG_S " DeInit", name_.c_str());
    pipelineThread_->RemoveTask(shared_from_this());
    {
        AutoLock lock1(jobMutex_);
        AutoLock lock2(stateMutex_);
        runningState_ = RunningState::STOPPED;
        topProcessUs_ = -1;
    }
    MEDIA_LOG_I_T(PUBLIC_LOG_S " DeInit done", name_.c_str());
}

TaskInner::~TaskInner()
{
    MEDIA_LOG_D_T(PUBLIC_LOG_S " dtor", name_.c_str());
}

void TaskInner::UpdateDelayTime(int64_t delayUs)
{
    if (!singleLoop_) {
        MEDIA_LOG_D_T("task " PUBLIC_LOG_S " UpdateDelayTime do nothing", name_.c_str());
        return;
    }
    MEDIA_LOG_D_T("task " PUBLIC_LOG_S " UpdateDelayTime enter topProcessUs:" PUBLIC_LOG_D64
        ", delayUs:" PUBLIC_LOG_D64, name_.c_str(), topProcessUs_, delayUs);
    pipelineThread_->LockJobState();
    AutoLock lock(stateMutex_);
    if (runningState_ != RunningState::STARTED) {
        pipelineThread_->UnLockJobState(false);
        return;
    }
    topProcessUs_ = GetNowUs() + delayUs;
    pipelineThread_->UnLockJobState(true);
    MEDIA_LOG_D_T("task " PUBLIC_LOG_S " UpdateDelayTime exit topProcessUs:" PUBLIC_LOG_D64,
        name_.c_str(), topProcessUs_);
}

void TaskInner::Start()
{
    MEDIA_LOG_I_FALSE_D_T(isStateLogEnabled_.load(), PUBLIC_LOG_S " Start", name_.c_str());
    pipelineThread_->LockJobState();
    AutoLock lock(stateMutex_);
    runningState_ = RunningState::STARTED;
    if (singleLoop_) {
        if (!job_) {
            MEDIA_LOG_D_T("task " PUBLIC_LOG_S " Start, job invalid", name_.c_str());
        }
        topProcessUs_ = GetNowUs();
    } else {
        UpdateTop();
    }
    pipelineThread_->UnLockJobState(true);
    MEDIA_LOG_I_FALSE_D(isStateLogEnabled_.load(), "task " PUBLIC_LOG_S " Start done, topProcessUs:%{public}" PRId64,
        name_.c_str(), topProcessUs_);
}

void TaskInner::Stop()
{
    if (pipelineThread_->IsRunningInSelf()) {
        MEDIA_LOG_W_T(PUBLIC_LOG_S " Stop done in self task", name_.c_str());
        runningState_ = RunningState::STOPPED;
        topProcessUs_ = -1;
        return;
    }
    MEDIA_LOG_I_T(">> " PUBLIC_LOG_S " Stop", name_.c_str());
    AutoLock lock1(jobMutex_);
    pipelineThread_->LockJobState();
    AutoLock lock2(stateMutex_);
    if (runningState_.load() == RunningState::STOPPED) {
        pipelineThread_->UnLockJobState(false);
        return;
    }
    runningState_ = RunningState::STOPPED;
    topProcessUs_ = -1;
    pipelineThread_->UnLockJobState(true);
    MEDIA_LOG_I_T(PUBLIC_LOG_S " Stop <<", name_.c_str());
}

void TaskInner::StopAsync()
{
    if (pipelineThread_->IsRunningInSelf()) {
        MEDIA_LOG_W_T(PUBLIC_LOG_S " Stop done in self task", name_.c_str());
        runningState_ = RunningState::STOPPED;
        topProcessUs_ = -1;
        return;
    }
    MEDIA_LOG_I_T(PUBLIC_LOG_S " StopAsync", name_.c_str());
    pipelineThread_->LockJobState();
    AutoLock lock(stateMutex_);
    bool stateChanged = false;
    if (runningState_.load() != RunningState::STOPPED) {
        runningState_ = RunningState::STOPPED;
        topProcessUs_ = -1;
        stateChanged = true;
    }
    pipelineThread_->UnLockJobState(stateChanged);
}

void TaskInner::Pause()
{
    if (pipelineThread_->IsRunningInSelf()) {
        RunningState state = runningState_.load();
        if (state == RunningState::STARTED) {
            MEDIA_LOG_I_FALSE_D_T(isStateLogEnabled_.load(),
                PUBLIC_LOG_S " Pause done in self task", name_.c_str());
            runningState_ = RunningState::PAUSED;
            topProcessUs_ = -1;
            return;
        } else {
            MEDIA_LOG_I_FALSE_D_T(isStateLogEnabled_.load(),
                PUBLIC_LOG_S " Pause skip in self task, curret State: " PUBLIC_LOG_D32, name_.c_str(), state);
            return;
        }
    }
    MEDIA_LOG_I_FALSE_D_T(isStateLogEnabled_.load(), PUBLIC_LOG_S " Pause", name_.c_str());
    AutoLock lock1(jobMutex_);
    pipelineThread_->LockJobState();
    AutoLock lock2(stateMutex_);
    RunningState state = runningState_.load();
    if (state != RunningState::STARTED) {
        pipelineThread_->UnLockJobState(false);
        return;
    }
    runningState_ = RunningState::PAUSED;
    topProcessUs_ = -1;
    pipelineThread_->UnLockJobState(true);
    MEDIA_LOG_I_FALSE_D_T(isStateLogEnabled_.load(), PUBLIC_LOG_S " Pause done.", name_.c_str());
}

void TaskInner::PauseAsync()
{
    if (pipelineThread_->IsRunningInSelf()) {
        RunningState state = runningState_.load();
        if (state == RunningState::STARTED) {
            MEDIA_LOG_I_FALSE_D_T(isStateLogEnabled_.load(),
                PUBLIC_LOG_S " PauseAsync done in self task", name_.c_str());
            runningState_ = RunningState::PAUSED;
            topProcessUs_ = -1;
            return;
        } else {
            MEDIA_LOG_I_FALSE_D_T(isStateLogEnabled_.load(),
                PUBLIC_LOG_S " PauseAsync skip in self task, curretState:%{public}d", name_.c_str(), state);
            return;
        }
    }
    MEDIA_LOG_I_FALSE_D_T(isStateLogEnabled_.load(), PUBLIC_LOG_S " PauseAsync", name_.c_str());
    pipelineThread_->LockJobState();
    AutoLock lock(stateMutex_);
    bool stateChanged = false;
    if (runningState_.load() == RunningState::STARTED) {
        runningState_ = RunningState::PAUSED;
        topProcessUs_ = -1;
        stateChanged = true;
    }
    pipelineThread_->UnLockJobState(stateChanged);
}

void TaskInner::RegisterJob(const std::function<int64_t()>& job)
{
    MEDIA_LOG_I_T(PUBLIC_LOG_S " RegisterHandler", name_.c_str());
    job_ = std::move(job);
}

void TaskInner::SubmitJobOnce(const std::function<void()>& job, int64_t delayUs, bool wait)
{
    MEDIA_LOG_D_T(PUBLIC_LOG_S " SubmitJobOnce", name_.c_str());
    int64_t time = InsertJob(job, delayUs, false);
    if (wait) {
        AutoLock lock(stateMutex_);
        replyCond_.Wait(lock, [this, time] { return msgQueue_.find(time) == msgQueue_.end(); });
    }
}

void TaskInner::SubmitJob(const std::function<void()>& job, int64_t delayUs, bool wait)
{
    MEDIA_LOG_D_T(PUBLIC_LOG_S " SubmitJob delayUs:%{public}" PRId64, name_.c_str(), delayUs);
    int64_t time = InsertJob(job, delayUs, true);
    if (wait) {
        AutoLock lock(stateMutex_);
        replyCond_.Wait(lock, [this, time] { return jobQueue_.find(time) == jobQueue_.end(); });
    }
}

void TaskInner::UpdateTop()
{
    // jobQueue_ is only handled in STARTED state, msgQueue_ always got handled.
    if (msgQueue_.empty() && ((runningState_.load() != RunningState::STARTED) || jobQueue_.empty())) {
        topProcessUs_ = -1;
        return;
    }
    if (msgQueue_.empty()) {
        topProcessUs_ = jobQueue_.begin()->first;
        topIsJob_ = true;
    } else if ((runningState_.load() != RunningState::STARTED) || jobQueue_.empty()) {
        topProcessUs_ = msgQueue_.begin()->first;
        topIsJob_ = false;
    } else {
        int64_t msgProcessTime = msgQueue_.begin()->first;
        int64_t jobProcessTime = jobQueue_.begin()->first;
        int64_t nowUs =  GetNowUs();
        if (msgProcessTime <= nowUs || msgProcessTime <= jobProcessTime) {
            topProcessUs_ = msgProcessTime;
            topIsJob_ = false;
        } else  {
            topProcessUs_ = jobProcessTime;
            topIsJob_ = true;
        }
    }
}

int64_t TaskInner::NextJobUs()
{
    AutoLock lock(stateMutex_);
    return topProcessUs_;
}

void TaskInner::HandleJob()
{
    AutoLock lock(jobMutex_);
    if (singleLoop_) {
        stateMutex_.lock();
        int64_t currentTopProcessUs = topProcessUs_;
        if (runningState_.load() == RunningState::PAUSED || runningState_.load() == RunningState::STOPPED) {
            topProcessUs_ = -1;
            stateMutex_.unlock();
            return;
        }
        // unlock stateMutex otherwise pauseAsync/stopAsync function will wait job finish.
        stateMutex_.unlock();
        int64_t nextDelay = (!job_) ? INVALID_DELAY_TIME_US : job_();

        AutoLock lock(stateMutex_);
        // if topProcessUs_ is -1, we already pause/stop in job_()
        // if topProcessUs_ is changed, we should ignore the returned delay time.
        if (topProcessUs_ != -1 && currentTopProcessUs == topProcessUs_) {
            topProcessUs_ = GetNowUs() + nextDelay;
        }
    } else {
        std::function<void()> nextJob;
        stateMutex_.lock();
        if (topIsJob_) {
            nextJob = std::move(jobQueue_.begin()->second);
            jobQueue_.erase(jobQueue_.begin());
        } else {
            nextJob = std::move(msgQueue_.begin()->second);
            msgQueue_.erase(msgQueue_.begin());
        }
        {
			// unlock stateMutex otherwise pauseAsync/stopAsync function will wait job finish.
            stateMutex_.unlock();
            nextJob();
            replyCond_.NotifyAll();
        }
        AutoLock lock(stateMutex_);
        UpdateTop();
    }
}

int64_t TaskInner::InsertJob(const std::function<void()>& job, int64_t delayUs, bool inJobQueue)
{
    pipelineThread_->LockJobState();
    AutoLock lock(stateMutex_);
    int64_t nowUs = GetNowUs();
    if (delayUs < 0) {
        delayUs = 0;
    }
    int64_t processTime = nowUs + delayUs;
    if (inJobQueue) {
        while (jobQueue_.find(processTime) != jobQueue_.end()) { // To prevent dropping job unexpectedly
            MEDIA_LOG_W_T("DUPLICATIVE jobQueue_ TIMESTAMP!!!");
            processTime++;
        }
        jobQueue_[processTime] = std::move(job);
    } else {
        while (msgQueue_.find(processTime) != msgQueue_.end()) { // To prevent dropping job unexpectedly
            MEDIA_LOG_W_T("DUPLICATIVE msgQueue_ TIMESTAMP!!!");
            processTime++;
        }
        msgQueue_[processTime] = std::move(job);
    }
    int64_t lastProcessUs = topProcessUs_;
    // update top if only new job is more emgercy or jobqueue is empty
    if (processTime <= topProcessUs_ || topProcessUs_ == -1) {
        UpdateTop();
    }
    // if top is updated we should wake pipeline thread
    pipelineThread_->UnLockJobState(lastProcessUs != topProcessUs_);
    return processTime;
}
} // namespace Media
} // namespace OHOS