#pragma once

#include <iostream>
#include <vector>
#include <pthread.h>
#include <mutex>
#include "sem.hpp"
const int DEFALT = 5;
template <class T>
class RingQueue
{
public:
    RingQueue(int default_num = DEFALT)
        :_ring_queue( DEFALT),
          _num( DEFALT),
          _c_step(0),
          _p_step(0),
          space_sem_( DEFALT),
          data_sem_(0)
    {
        pthread_mutex_init(&clock, nullptr);
        pthread_mutex_init(&plock, nullptr);
    }
    ~RingQueue()
    {
        pthread_mutex_destroy(&clock);
        pthread_mutex_destroy(&plock);
    }
    
    // 生产者的临界资源是下标
    void push(const T &in)
    {
        space_sem_.p(); // 先申请信号量
        pthread_mutex_lock(&plock);
        _ring_queue[_p_step++] = in;
        _p_step %= _num;
        pthread_mutex_unlock(&plock);
        data_sem_.v();
    }
    // 消费者的临界资源是下标
    void pop(T *out)
    {
        data_sem_.p();
        pthread_mutex_lock(&clock);
        // 一定是竞争成功的消费者线程 -- 就一个！
        *out = _ring_queue[_c_step++];
        _c_step %= _num;
        pthread_mutex_unlock(&clock);
        space_sem_.v();
    }

private:
    std::vector<T> _ring_queue;
    int _num;
    int _c_step; // 消费下标
    int _p_step; // 生产下标
    Sem space_sem_;
    Sem data_sem_;
    pthread_mutex_t clock;
    pthread_mutex_t plock;
};