#pragma once

#ifndef MIJIN_ASYNC_TASK_MUTEX_HPP_INCLUDED
#define MIJIN_ASYNC_TASK_MUTEX_HPP_INCLUDED 1

#include "./coroutine.hpp"
#include "../internal/common.hpp"

namespace mijin
{
class [[nodiscard]] TaskMutexLock
{
private:
    class TaskMutex* mutex_;

public:
    explicit TaskMutexLock(class TaskMutex* mutex) MIJIN_NOEXCEPT : mutex_(mutex) {}
    TaskMutexLock(const TaskMutexLock&) = delete;
    TaskMutexLock(TaskMutexLock&& other) MIJIN_NOEXCEPT : mutex_(std::exchange(other.mutex_, nullptr)) {}

    TaskMutexLock& operator=(const TaskMutexLock&) = delete;
    inline TaskMutexLock& operator=(TaskMutexLock&& other) MIJIN_NOEXCEPT;
    inline ~TaskMutexLock() MIJIN_NOEXCEPT;
};

class TaskMutex
{
private:
    bool locked_ = false;
public:
    Task<TaskMutexLock> c_lock()
    {
        while (locked_)
        {
            co_await c_suspend();
        }
        locked_ = true;
        co_return TaskMutexLock(this);
    }
    [[nodiscard]] inline bool isLocked() const MIJIN_NOEXCEPT { return locked_; }

    friend class TaskMutexLock;
};

TaskMutexLock::~TaskMutexLock() MIJIN_NOEXCEPT
{
    if (mutex_)
    {
        mutex_->locked_ = false;
    }
}

TaskMutexLock& TaskMutexLock::operator=(TaskMutexLock&& other) MIJIN_NOEXCEPT
{
    if (mutex_)
    {
        mutex_->locked_ = false;
    }
    mutex_ = std::exchange(other.mutex_, nullptr);
    return *this;
}
}

#endif // MIJIN_ASYNC_TASK_MUTEX_HPP_INCLUDED