/*
 * Copyright (c) 2016 Zibin Zheng <znbin@qq.com>
 * All rights reserved
 */

#include "multi_timer.h"

//timer handle list head.
static struct Timer* head_handle = NULL;

//Timer ticks
//static uint32_t _timer_ticks = 0;
static uint16_t _timer_ticks = 0;


/**
  * @brief  Initializes the timer struct handle.
  * @param  handle: the timer handle strcut.
  * @param  timeout_cb: timeout callback.
  * @param  repeat: repeat interval time.
  * @retval None
  */
void timer_init_Head ( void )
{
    head_handle = NULL;
}
void timer_init ( struct Timer* handle, void ( *timeout_cb ) (), uint32_t timeout, uint32_t repeat )
{
    // memset(handle, 0, sizeof(struct Timer));
    handle->timeout_cb = timeout_cb;
    handle->timeout = _timer_ticks + timeout;
    handle->repeat = repeat;
}

void timer_app ( struct Timer* handle, void ( *timeout_cb ) (), uint32_t timeout, uint32_t repeat )
{
    timer_init ( handle, timeout_cb, timeout, repeat );
    timer_start ( handle );
}
/**
  * @brief  Start the timer work, add the handle into work list.
  * @param  btn: target handle strcut.
  * @retval 0: succeed. -1: already exist.
  */
int timer_start ( struct Timer* handle )
{
    struct Timer* target = head_handle;

    while ( target )
    {
        if ( target == handle ) return -1;	//already exist.

        target = target->next;
    }

    handle->next = head_handle;
    head_handle = handle;
    return 0;
}

/**
  * @brief  Stop the timer work, remove the handle off work list.
  * @param  handle: target handle strcut.
  * @retval None
  */
void timer_stop ( struct Timer* handle )
{
    struct Timer** curr;

    for ( curr = &head_handle; *curr; )
    {
        struct Timer* entry = *curr;

        if ( entry == handle )
        {
            *curr = entry->next;
//			free(entry);
        }
        else
            curr = &entry->next;
    }
}

/**
  * @brief  main loop.
  * @param  None.
  * @retval None
  */
void timer_loop()
{
    struct Timer* target;

    for ( target = head_handle; target; target = target->next )
    {
        if ( ( ( target->timeout < TIMER_MAX ) && ( _timer_ticks >= target->timeout ) )	|| \
                ( ( target->timeout >= TIMER_MAX ) && ( _timer_ticks + TIMER_MAX >= target->timeout ) )
           )
        {
            if ( target->repeat == 0 )  		//Ò»´ÎÐÔ
            {
                timer_stop ( target );
            }
            else  						//Ñ­»·
            {
                target->timeout = _timer_ticks + target->repeat;
            }

            target->timeout_cb();
        }
    }
}

/**
  * @brief  background ticks, timer repeat invoking interval 1ms.
  * @param  None.
  * @retval None.
  */
void timer_ticks()
{
    _timer_ticks += TIMER_TICK;

    if ( _timer_ticks >= TIMER_MAX )	_timer_ticks = 0;
}