#pragma once
#include<pthread.h>
#include"Task.hpp"
#include<queue>
#define NUM 5
//基于阻塞队列的线程池
class ThreadPool{
  private:
    pthread_mutex_t mtx;
    pthread_cond_t cond;
    std::queue<Task> q;
    static ThreadPool* inst;
    ThreadPool()
    {
      pthread_mutex_init(&mtx,nullptr);
      pthread_cond_init(&cond,nullptr);
    }
    ThreadPool(const ThreadPool&) = delete;
    ThreadPool& operator=(const ThreadPool&) = delete;
  public:
    static ThreadPool* GetInstance()
    {
      static pthread_mutex_t lock = PTHREAD_MUTEX_INITIALIZER;
      if(inst == nullptr)
      {
        pthread_mutex_lock(&lock);
        if(inst == nullptr)
        {
          //创建线程池并初始化
          inst = new ThreadPool;
          inst->InitThreadPool();
        }
        pthread_mutex_unlock(&lock);
      }
      return inst;
    }
    void ThreadWait()
    {
      pthread_cond_wait(&cond,&mtx);
    }
    void ThreadWakeup()
    {
      pthread_cond_signal(&cond);
    }
    void Lock()
    {
      pthread_mutex_lock(&mtx);
    }
    void Unlock()
    {
      pthread_mutex_unlock(&mtx);
    }
    bool IsEmpty()
    {
      return q.empty();
    }
    Task& Front()
    {
      return q.front();
    }
    void Pop()
    {
      return q.pop();
    }
    static void* ThreadRun(void* args)
    {
      ThreadPool* tp = (ThreadPool*) args;
      while(1)
      {
        tp->Lock();
        while(tp->IsEmpty())
        {
          tp->ThreadWait();
        }
        Task& t = tp->Front();
        tp->Pop();
        tp->Unlock();
        //在外面处理任务
        t();

      }
    }
    void PutTask(const Task& t)
    {
      Lock();
      q.push(t);
      ThreadWakeup();
      Unlock();
    }
    void InitThreadPool()
    {
      for(int i = 0;i < NUM;++i)
      {
        pthread_t tid;
        if(pthread_create(&tid,nullptr,ThreadRun,this) != 0)
        {
          LOG(FATAL,"create ThreadPool fail!");
        }
        pthread_detach(tid);
      }
      LOG(INFO,"InitThreadPool");
    }
    ~ThreadPool()
    {
      pthread_mutex_destroy(&mtx);
      pthread_cond_destroy(&cond);
    }
};
ThreadPool* ThreadPool::inst = nullptr;