#include"Task.hpp"
#include<string>
#include<vector>

#include<cassert>
#include<ctime>

#include<unistd.h>
#include<sys/types.h>
#include<sys/wait.h>

const int processNum = 10;   //一次性创建5个子进程
std::vector<task_t> tasks;

class channel
{
public:
    channel(int cmdFd, pid_t slaverId, const std::string &processName)
    :_cmdFd(cmdFd)
    ,_slaverId(slaverId)
    ,_processName(processName)
    {}

public:
    int _cmdFd; //发送任务的文件名描述符
    pid_t _slaverId;    //子进程pid
    std::string _processName;    //子进程名字


};

void Slaver()
{
    int cnt = 2;
    while(true)
    {
        int cmdCode = 0;
        int n = read(0, &cmdCode, sizeof(cmdCode));
        if(n == sizeof(int))
        {
            std::cout << "slaver say@get a command:" << getpid() << " : cmdCode: " << cmdCode << std::endl;
            if(cmdCode >= 0 && cmdCode < tasks.size())  tasks[cmdCode]();
        }
        if(n == 0)  break;   
    }
}

void InitProcessPool(std::vector<channel> *channels)
{
    std::vector<int> oldfds;
    for(int i = 0; i < processNum; i++)
    {
        int pipefd[2] = {0};
        //管道创建
        int n = pipe(pipefd);
        assert(!n);
        (void)n;


        pid_t id = fork();
        if(id == 0)
        {
            //关闭上一个写端
            for(auto e : oldfds) close(e);
            //child 读端
            close(pipefd[1]);
            dup2(pipefd[0],0);  //重定向，从管道里读
            close(pipefd[0]);
            Slaver();
            exit(0);

        }

        //father 写端
        close(pipefd[0]);
        std::string name = "process -" + std::to_string(i);
        //匿名对象
        channels->push_back(channel(pipefd[1], id, name));
        oldfds.push_back(pipefd[1]);
    }
}

void Debug(const std::vector<channel> &channels)
{
    for(const auto &e : channels)
    {
        std::cout << e._cmdFd << " " << e._processName.c_str() << " " << e._slaverId << std::endl;
    }
}

void CtrlProcess(const std::vector<channel> &channels)
{
    int cnt = 5;
    while(cnt--)
    {
        //随机发布任务
        int cmdCode = rand()%tasks.size();
        
        //选择进程
        int processPos = rand()%sizeof(channels.size());
        std::cout << "father say@" << "command:" << cmdCode << " already sendto " << channels[processPos]._slaverId << " process name:"
        << channels[processPos]._cmdFd << std::endl;

        //发送任务
        write(channels[processPos]._cmdFd, &cmdCode, sizeof(cmdCode));
        sleep(1);
    }
}

void QuitProcess(const std::vector<channel> &channels)
{
    //关闭文件描述符
    for(const auto &e : channels)
    {
        close(e._cmdFd);
        std::cout << e._cmdFd << " " << e._processName << " " << e._slaverId << std::endl;
        sleep(1);
        waitpid(e._slaverId, nullptr, 0);
    }
}
int main()
{
    LoadTask(&tasks);
    srand(time(nullptr)^getpid()^1023);
    //进程组织
    std::vector<channel> channels;

    //初始化--创建子进程、建立通信信道
    InitProcessPool(&channels);

    Debug(channels); 
    
    //控制子进程
    CtrlProcess(channels);

    //sleep(1000);
    //清理收尾
    QuitProcess(channels);
    return 0;
}