/*
 * Copyright 2022-2024 The Onps Project Author All Rights Reserved.
 *
 * Author：Neo-T
 *
 * Licensed under the Apache License 2.0 (the "License").  You may not use
 * this file except in compliance with the License.  You can obtain a copy
 * in the file LICENSE in the source distribution or at
 * http://www.onps.org.cn/apache2.0.txt
 *
 */
#include "port/datatype.h"
#include "port/sys_config.h"
#include "onps_errors.h"
#include "port/os_datatype.h"
#include "port/os_adapter.h"
#include "mmu/buddy.h"
#include "onps_utils.h"
#include "onps_input.h"

#define SYMBOL_GLOBALS
#include "one_shot_timer.h"
#undef SYMBOL_GLOBALS

#include "ip/tcp_link.h"
#include "ip/tcp.h"

typedef struct _ST_ONESHOTTIMER_ { //* 定时器
    PST_ONESHOTTIMER pstNext;
    PFUN_ONESHOTTIMEOUT_HANDLER pfunTimeoutHandler;
    void *pvParam;
    INT nTimeoutCount;	//* 溢出值，单位：秒	
} ST_ONESHOTTIMER, *PST_ONESHOTTIMER; 

static HMUTEX l_hMtxFreeOneShotTimer;	//* 可用定时器链表同步锁
static HMUTEX l_hMtxOneShotTimer;		//* 正在计时的定时器链表同步锁
static ST_ONESHOTTIMER l_staOneShotTimerNode[ONE_SHOT_TIMER_NUM];
static PST_ONESHOTTIMER l_pstFreeOneShotTimerLink;
static PST_ONESHOTTIMER l_pstOneShotTimerLink = NULL;
static BOOL l_blIsRunning = TRUE; 
static UCHAR l_ubThreadExitFlag = TRUE; 

//* 定时器初始化（栈开始工作前必须要先调用这个函数进行定时器初始化）
BOOL one_shot_timer_init(EN_ONPSERR *penErr)
{
	INT i; 
	for (i = 0; i < ONE_SHOT_TIMER_NUM - 1; i++) //* 将定时器链表链接起来
	{
		l_staOneShotTimerNode[i].pstNext = &l_staOneShotTimerNode[i + 1];
	}
	l_staOneShotTimerNode[ONE_SHOT_TIMER_NUM - 1].pstNext = NULL; //* 最后一个节点单独赋值
	l_pstFreeOneShotTimerLink = &l_staOneShotTimerNode[0];		  //* 接入链表头，形成真正的链表

	do {
    #if 1
		//* 建立可用定时器队列同步锁
		l_hMtxFreeOneShotTimer = os_thread_mutex_init();
		if (INVALID_HMUTEX == l_hMtxFreeOneShotTimer)
		{
			*penErr = ERRMUTEXINITFAILED; 
			break; 
		}

		//* 建立已开启计时的定时器队列同步锁
		l_hMtxOneShotTimer = os_thread_mutex_init();
		if (INVALID_HMUTEX == l_hMtxOneShotTimer)
		{
			*penErr = ERRMUTEXINITFAILED;
			break;
		}		
    #endif

		return TRUE; 
	} while (FALSE); 	

	if (INVALID_HMUTEX != l_hMtxFreeOneShotTimer)
		os_thread_mutex_uninit(l_hMtxFreeOneShotTimer);	
	
	return FALSE; 
}

//* 定时器去初始化
void one_shot_timer_uninit(void)
{
    l_blIsRunning = FALSE; 

    while (!l_ubThreadExitFlag)
        os_sleep_secs(1);     

    if (INVALID_HMUTEX != l_hMtxFreeOneShotTimer)
        os_thread_mutex_uninit(l_hMtxFreeOneShotTimer);

    if (INVALID_HMUTEX != l_hMtxOneShotTimer)
        os_thread_mutex_uninit(l_hMtxOneShotTimer);    
}

//* 结束两个定时器线程，并释放所有工作队列，并归还给系统
void one_shot_timer_stop(void)
{
	l_blIsRunning = FALSE;
}

//#if SUPPORT_SACK
//void thread_one_shot_timer_count(void *pvParam)
//{
//    PST_ONESHOTTIMER pstTimer, pstPrevTimer, pstNextTimer;
//
//    //os_critical_init();
//
//    l_ubThreadExitFlag = FALSE;
//    while (l_blIsRunning)
//    {
//        os_thread_mutex_lock(l_hMtxOneShotTimer);
//        //os_enter_critical();
//        {
//            pstNextTimer = l_pstOneShotTimerLink;
//            pstPrevTimer = NULL;
//            pstTimer = NULL;
//            while (pstNextTimer)
//            {
//                if (pstNextTimer->nTimeoutCount-- <= 0)
//                {
//                    //* 先从计时器队列摘除
//                    if (pstPrevTimer)
//                        pstPrevTimer->pstNext = NULL;
//                    else
//                        l_pstOneShotTimerLink = NULL;
//                    pstTimer = pstNextTimer;
//                    break;
//                }
//                else //* 计时尚未结束，检查下一个节点
//                {
//                    pstPrevTimer = pstNextTimer;
//                    pstNextTimer = pstNextTimer->pstNext;
//                }
//            }
//        }
//        os_thread_mutex_unlock(l_hMtxOneShotTimer);
//        //os_exit_critical();
//
//        //* 如果存在溢出节点则开始执行溢出操作
//        if (pstTimer)
//        {
//            pstNextTimer = pstTimer;
//            while (pstNextTimer)
//            {
//                //* 保存当前要操作的定时器并在操作之前推进到下一个溢出定时器
//                pstTimer = pstNextTimer;
//                pstNextTimer = pstNextTimer->pstNext;
//
//                //* 执行溢出函数并归还给系统
//                pstTimer->pfunTimeoutHandler(pstTimer->pvParam);
//                one_shot_timer_free(pstTimer);
//            }
//        }
//
//        //* 这个休眠可以不用特别精确（1秒左右），我们的应用场景足够了
//        os_sleep_secs(1);
//    }
//
//    //* 回收资源
//    os_thread_mutex_lock(l_hMtxOneShotTimer);
//    //os_enter_critical();
//    {
//        pstNextTimer = l_pstOneShotTimerLink;
//        while (pstNextTimer)
//        {
//            //* 先从计时器队列摘除
//            pstTimer = pstNextTimer;
//            pstNextTimer = pstNextTimer->pstNext;
//
//            //* 归还
//            one_shot_timer_free(pstTimer);
//        }
//    }
//    os_thread_mutex_unlock(l_hMtxOneShotTimer);
//    //os_exit_critical();
//
//    l_ubThreadExitFlag = TRUE;
//}
//#else
//* 这并不是一个精确的定时器计时队列，这依赖于休眠精度以及队列长度，但对于我们的应用场景来说已经足够使用
void thread_one_shot_timer_count(void *pvParam)
{
	PST_ONESHOTTIMER pstTimer, pstPrevTimer, pstNextTimer; 
#if 1
    USHORT usTimeCount = 0;
    PST_TCPLINK pstNextLink = NULL;
    UINT unDelayAckTimeout = TCP_ACK_DELAY_MSECS < 40 || TCP_ACK_DELAY_MSECS > 200 ? 100 - 1 : TCP_ACK_DELAY_MSECS - 1; 
#endif

    //os_critical_init();

    l_ubThreadExitFlag = FALSE;
	while (l_blIsRunning)
	{
    #if SUPPORT_SACK
        tcp_send_timer_lock();
        {
            PSTCB_TCPSENDTIMER pstcbTcpSndTimer = NULL; 
            do {
                pstcbTcpSndTimer = tcp_send_timer_get_next(pstcbTcpSndTimer);
                if (pstcbTcpSndTimer)
                {										
                    if (pstcbTcpSndTimer->pstLink->bState != TLSCONNECTED)
                        continue; 

                    //* 是否大于RTO，大于rto则重新发送之   					
                    if (os_get_system_msecs() - pstcbTcpSndTimer->unSendMSecs > (UINT)pstcbTcpSndTimer->usRto)
                    {        
						if (pstcbTcpSndTimer->bIsNotSacked)
						{
							//* 重新发送数据
							EN_ONPSERR enErr;
							UCHAR *pubData = (UCHAR *)buddy_alloc(pstcbTcpSndTimer->unRight - pstcbTcpSndTimer->unLeft, &enErr);
							if (pubData)
							{
								UINT unStartReadIdx = pstcbTcpSndTimer->unLeft % TCPSNDBUF_SIZE;
								UINT unEndReadIdx = pstcbTcpSndTimer->unRight % TCPSNDBUF_SIZE;
								if (unEndReadIdx > unStartReadIdx)
									memcpy(pubData, pstcbTcpSndTimer->pstLink->stcbSend.pubSndBuf + unStartReadIdx, unEndReadIdx - unStartReadIdx);
								else
								{
									UINT unCpyBytes = TCPSNDBUF_SIZE - unStartReadIdx;
									memcpy(pubData, pstcbTcpSndTimer->pstLink->stcbSend.pubSndBuf + unStartReadIdx, unCpyBytes);
									memcpy(pubData + unCpyBytes, pstcbTcpSndTimer->pstLink->stcbSend.pubSndBuf, unEndReadIdx);
								}
						
								//* 重发dup ack的数据块
								tcp_send_data_ext(pstcbTcpSndTimer->pstLink->stcbWaitAck.nInput, pubData, pstcbTcpSndTimer->unRight - pstcbTcpSndTimer->unLeft, pstcbTcpSndTimer->unLeft + 1);
								buddy_free(pubData);

								//* 每重发一次，rto加倍
								if (pstcbTcpSndTimer->usRto < RTO_MAX)
									pstcbTcpSndTimer->usRto *= 2;

								//* 将timer从当前位置转移到队列的尾部，并重新开启重传计时
								pstcbTcpSndTimer->unSendMSecs = os_get_system_msecs();
								pstcbTcpSndTimer->bIsNotSacked = TRUE;
								tcp_send_timer_node_del_unsafe(pstcbTcpSndTimer);
								tcp_send_timer_node_put_unsafe(pstcbTcpSndTimer);

								pstcbTcpSndTimer = NULL;
								continue;
							}
							else
							{
						#if SUPPORT_PRINTF && DEBUG_LEVEL
							#if PRINTF_THREAD_MUTEX
								os_thread_mutex_lock(o_hMtxPrintf);
							#endif
								printf("thread_one_shot_timer_count() caught an error, %s\r\n", onps_error(enErr));
							#if PRINTF_THREAD_MUTEX
								os_thread_mutex_unlock(o_hMtxPrintf);
							#endif
						#endif
							}
						}
						else
							continue; 
                    }				
                    
                    break; //* 新发送数据的节点会被放到尾部，换言之定时器队列发送时间为递增序列，所以当前节点一旦小于RTO，则后续的亦会小于，不必继续查找了
                }
            } while (pstcbTcpSndTimer);  
        }
        tcp_send_timer_unlock(); 		
    #endif

    #if 1
        //* 延迟tcp ack处理
        tcp_link_lock();
        {
            do {
                pstNextLink = tcp_link_list_used_get_next(pstNextLink);
                if (pstNextLink)
                {
                    if (pstNextLink->bState == TLSCONNECTED)
                    {                        
                        if (!pstNextLink->uniFlags.stb16.no_delay_ack && pstNextLink->stPeer.bIsNotAcked)
                        {
                            if (os_get_system_msecs() - pstNextLink->stPeer.unStartMSecs > unDelayAckTimeout)
                            {          
							#if SUPPORT_IPV6
								if(AF_INET == pstNextLink->stLocal.pstHandle->bFamily)
									tcp_send_ack(pstNextLink, pstNextLink->stLocal.pstHandle->stSockAddr.saddr_ipv4, pstNextLink->stLocal.pstHandle->stSockAddr.usPort, pstNextLink->stPeer.stSockAddr.saddr_ipv4, pstNextLink->stPeer.stSockAddr.usPort); 
								else
									tcpv6_send_ack(pstNextLink, pstNextLink->stLocal.pstHandle->stSockAddr.saddr_ipv6, pstNextLink->stLocal.pstHandle->stSockAddr.usPort, pstNextLink->stPeer.stSockAddr.saddr_ipv6, pstNextLink->stPeer.stSockAddr.usPort);
							#else
                                tcp_send_ack(pstNextLink, pstNextLink->stLocal.pstHandle->stSockAddr.saddr_ipv4, pstNextLink->stLocal.pstHandle->stSockAddr.usPort, pstNextLink->stPeer.stSockAddr.saddr_ipv4, pstNextLink->stPeer.stSockAddr.usPort);
							#endif
                                pstNextLink->stPeer.bIsNotAcked = FALSE;
                            }
                        }
                    }
                }
            } while (pstNextLink);
        }
        tcp_link_unlock();

        if (usTimeCount++ > 999)        
        {
    #endif			
            os_thread_mutex_lock(l_hMtxOneShotTimer);
            //os_enter_critical();
            {
                pstNextTimer = l_pstOneShotTimerLink;
                pstPrevTimer = NULL;
                pstTimer = NULL;
                while (pstNextTimer)
                {
                    if (--pstNextTimer->nTimeoutCount <= 0)
                    {

                        //* 先从计时器队列摘除
                        if (pstPrevTimer)
                            pstPrevTimer->pstNext = NULL;
                        else
                            l_pstOneShotTimerLink = NULL;                        

                        pstTimer = pstNextTimer;                         
                        break;
                    }
                    else //* 计时尚未结束，检查下一个节点
                    {
                        pstPrevTimer = pstNextTimer;
                        pstNextTimer = pstNextTimer->pstNext;
                    }
                }
            }
            os_thread_mutex_unlock(l_hMtxOneShotTimer);
            //os_exit_critical();

            //* 如果存在溢出节点则开始执行溢出操作
            if (pstTimer)
            {
                pstNextTimer = pstTimer;                
                while (pstNextTimer)
                {
                    //* 保存当前要操作的定时器并在操作之前推进到下一个溢出定时器
                    pstTimer = pstNextTimer;
                    pstNextTimer = pstNextTimer->pstNext;

                    //* 执行溢出函数并归还给系统                    
                    pstTimer->pfunTimeoutHandler(pstTimer->pvParam);                    
                    one_shot_timer_free(pstTimer);
                }                
            }

    #if 0
            //* 这个休眠可以不用特别精确（1秒左右），我们的应用场景足够了
            os_sleep_secs(1);
    #else
            usTimeCount = 0;
        }
        os_sleep_ms(1);        
    #endif
	}

	//* 回收资源
	os_thread_mutex_lock(l_hMtxOneShotTimer);
    //os_enter_critical();
	{
		pstNextTimer = l_pstOneShotTimerLink;
		while (pstNextTimer)
		{
			//* 先从计时器队列摘除
			pstTimer = pstNextTimer;
			pstNextTimer = pstNextTimer->pstNext;

			//* 归还
			one_shot_timer_free(pstTimer);
		}
	}
	os_thread_mutex_unlock(l_hMtxOneShotTimer);
    //os_exit_critical();

    l_ubThreadExitFlag = TRUE;
}
//#endif

//* 分配一个新的one-shot定时器
PST_ONESHOTTIMER one_shot_timer_new(PFUN_ONESHOTTIMEOUT_HANDLER pfunTimeoutHandler, void *pvParam, INT nTimeoutCount)
{
	PST_ONESHOTTIMER pstTimer = NULL;

    //os_critical_init();

	//* 从可用队列中摘取一个空闲节点
	os_thread_mutex_lock(l_hMtxFreeOneShotTimer);
    //os_enter_critical();
	{
		pstTimer = l_pstFreeOneShotTimerLink;
		if (l_pstFreeOneShotTimerLink)
			l_pstFreeOneShotTimerLink = l_pstFreeOneShotTimerLink->pstNext;
	}
	os_thread_mutex_unlock(l_hMtxFreeOneShotTimer);
    //os_exit_critical();

	//* 存在空闲节点则赋值并挂接到计时队列中
	if (pstTimer)
	{
		//* 先赋值再挂载，否则可能导致计数线程出现错误        
		pstTimer->pfunTimeoutHandler = pfunTimeoutHandler;
		pstTimer->pvParam = pvParam;
        nTimeoutCount = (nTimeoutCount == 1 ? 2 : nTimeoutCount);
		pstTimer->nTimeoutCount = nTimeoutCount;

		//* 挂接到计时队列中，开始计数
		os_thread_mutex_lock(l_hMtxOneShotTimer);
        //os_enter_critical();
		{
            //* 按照降序挂载到链表
            PST_ONESHOTTIMER pstNextTimer = l_pstOneShotTimerLink; 
            PST_ONESHOTTIMER pstPrevTimer = NULL; 
            while (pstNextTimer)
            {
                if (pstNextTimer->nTimeoutCount > nTimeoutCount)                
                    pstPrevTimer = pstNextTimer; 
                else
                    break;                 

                pstNextTimer = pstNextTimer->pstNext;
            }

            if (pstPrevTimer) //* 说明是中间部分节点
            {
                pstTimer->pstNext = pstPrevTimer->pstNext; 
                pstPrevTimer->pstNext = pstTimer;
            }
            else //* 直接挂载到头部（头部节点计数比新分配的计数要小，直接挂载到头部）
            {
                pstTimer->pstNext = l_pstOneShotTimerLink;
                l_pstOneShotTimerLink = pstTimer;
            }			
		}
		os_thread_mutex_unlock(l_hMtxOneShotTimer);
        //os_exit_critical();
	}

	return pstTimer; 
}

void one_shot_timer_recount(PST_ONESHOTTIMER pstTimer, INT nTimeoutCount)
{
	PST_ONESHOTTIMER pstNextTimer;

	//* 必须大于0才可
	if (nTimeoutCount <= 0)
		return; 

    //os_critical_init();

	//*	确保计时队列中还存在这个节点，否则没必要重计数了
	os_thread_mutex_lock(l_hMtxOneShotTimer);
    //os_enter_critical();
	{
        PST_ONESHOTTIMER pstPrevTimer = NULL;
		pstNextTimer = l_pstOneShotTimerLink;        
		while (pstNextTimer)
		{
            //* 找到了这个节点，则先从中摘除以重新排序
			if (pstTimer == pstNextTimer)
			{
                if (pstPrevTimer)                
                    pstPrevTimer->pstNext = pstTimer->pstNext;                
                else                
                    l_pstOneShotTimerLink = l_pstOneShotTimerLink->pstNext;                 
				break; 
			}
             
            pstPrevTimer = pstNextTimer; 
			pstNextTimer = pstNextTimer->pstNext; 
		}

        //* 如果不为空，意味着匹配，则重新排序后挂载到链表上
        if (pstNextTimer)
        {
            pstTimer->nTimeoutCount = nTimeoutCount; 
            
            pstNextTimer = l_pstOneShotTimerLink;
            pstPrevTimer = NULL;
            while (pstNextTimer)
            {
                if (pstNextTimer->nTimeoutCount > nTimeoutCount)
                    pstPrevTimer = pstNextTimer;
                else
                    break;

                pstNextTimer = pstNextTimer->pstNext;
            }

            if (pstPrevTimer) //* 说明是中间部分节点
            {
                pstTimer->pstNext = pstPrevTimer->pstNext;
                pstPrevTimer->pstNext = pstTimer;
            }
            else //* 直接挂载到头部（头部节点计数比新分配的计数要小，直接挂载到头部）
            {
                pstTimer->pstNext = l_pstOneShotTimerLink;
                l_pstOneShotTimerLink = pstTimer;
            }
        }
	}
	os_thread_mutex_unlock(l_hMtxOneShotTimer); 
    //os_exit_critical();
}

//* 这个函数的目的是安全停止计时器并将其归还给系统，不再占用，与one_shot_timer_free()函数不同
//* ，该函数需要先判断其是否依然还在计数，是，则停止并归还给系统，否则不做任何处理
void one_shot_timer_safe_free(PST_ONESHOTTIMER pstTimer)
{
	PST_ONESHOTTIMER pstNextTimer, pstPrevTimer;
	BOOL blIsExist = FALSE; 

	if (NULL == pstTimer)
		return; 

    //os_critical_init();

	//*	确保计时队列中还存在这个节点，否则不做任何处理
	os_thread_mutex_lock(l_hMtxOneShotTimer);
    //os_enter_critical();
	{
		pstNextTimer = l_pstOneShotTimerLink;
		pstPrevTimer = NULL; 
		while (pstNextTimer)
		{
			if (pstTimer == pstNextTimer) //* 存在这个定时器，从计时器队列摘除之
			{
				if (pstPrevTimer)
					pstPrevTimer->pstNext = pstTimer->pstNext;
				else
					l_pstOneShotTimerLink = pstTimer->pstNext;

				blIsExist = TRUE;
				
				break;
			}

			pstPrevTimer = pstNextTimer; 
			pstNextTimer = pstNextTimer->pstNext;
		}
	}
	os_thread_mutex_unlock(l_hMtxOneShotTimer);
    //os_exit_critical();

	//* 存在则归还给系统（这里未使用函数调用的方式以减少入栈出栈带来的内存及性能损耗）
	if (blIsExist)
	{
		os_thread_mutex_lock(l_hMtxFreeOneShotTimer);
        //os_enter_critical();
		{
			pstTimer->pstNext = l_pstFreeOneShotTimerLink;
			l_pstFreeOneShotTimerLink = pstTimer;
		}
		os_thread_mutex_unlock(l_hMtxFreeOneShotTimer);
        //os_exit_critical();
	}
}

//* 释放占用的定时器资源，不做任何判断直接释放并归还给系统
void one_shot_timer_free(PST_ONESHOTTIMER pstTimer)
{
    //os_critical_init();

	if (NULL == pstTimer)
		return;

	os_thread_mutex_lock(l_hMtxFreeOneShotTimer);
    //os_enter_critical();
	{		        
		pstTimer->pstNext = l_pstFreeOneShotTimerLink; 					
		l_pstFreeOneShotTimerLink = pstTimer;
	}
	os_thread_mutex_unlock(l_hMtxFreeOneShotTimer);
    //os_exit_critical(); 
}