/********************************** (C) COPYRIGHT *******************************
 * File Name          : usb_endp.c
 * Author             : WCH
 * Version            : V1.0.0
 * Date               : 2021/08/08
 * Description        : Endpoint routines
*********************************************************************************
* Copyright (c) 2021 Nanjing Qinheng Microelectronics Co., Ltd.
* Attention: This software (modified or not) and binary are used for 
* microcontroller manufactured by Nanjing Qinheng Microelectronics.
*******************************************************************************/ 
#include "usb_lib.h"
#include "usb_mem.h"

#include "hw_config.h"
#include "usb_desc.h"
#include "usb_istr.h"
#include "usb_prop.h"
#include "usb_pwr.h"

#include "periph/usb/cdc.h"



uint8_t USBD_Endp3_Busy;
uint16_t USB_Rx_Cnt = 0; 
uint8_t HID_Buffer[DEF_USBD_MAX_PACK_SIZE];



/*********************************************************************
 * @fn      EP1_IN_Callback
 *
 * @brief  Endpoint 1 IN.
 *
 * @return  none
 */
void EP1_IN_Callback (void)
{ 
	
}

/*********************************************************************
 * @fn      EP2_OUT_Callback
 *
 * @brief  Endpoint 2 OUT.
 *
 * @return  none
 */
void EP2_OUT_Callback (void)
{ 
	uint16_t cnt;
	uint16_t remain;
	uint8_t dat[DEF_USB_FS_PACKET_LEN];
	uint8_t *buf = dat;


    // receive data
	cnt = GetEPRxCount(EP2_OUT & 0x7F);
    PMAToUserBufferCopy(buf, GetEPRxAddr(EP2_OUT & 0x7F), cnt);

    // copy data to buffer
    // note: this is slower, but we are using circular buffer,
    //       so this is easier without seriously reworking code
    remain = cnt;

    if (cnt >= DEF_CDC_FROM_HOST_BUF_LEN - Cdc.from_host_ptr) {
        // if we've got too much data, then copy what will fit to end of buffer
        remain = DEF_CDC_FROM_HOST_BUF_LEN - Cdc.from_host_ptr;
        memcpy(cdc_from + Cdc.from_host_ptr, buf, remain);

        // set pointers
        Cdc.from_host_ptr = 0;

        buf += remain;
        remain = cnt - remain;
    }

    // fill the buffer
    memcpy(cdc_from + Cdc.from_host_ptr, buf, remain);

    // todo: handle not overflowing
    /*
	if( Cdc.Tx_RemainNum >= ( DEF_CDC_TX_BUF_NUM_MAX - 2 ) ) {
        Cdc.usb_from_host_stop_flag = 1;
    }
    else
    */
    {
        SetEPRxValid(ENDP2);
    }
}


/*********************************************************************
 * @fn      EP3_IN_Callback
 *
 * @brief  Endpoint 3 IN.
 *
 * @return  none
 */
void EP3_IN_Callback (void)
{ 
	USBD_Endp3_Busy = 0;
	Cdc.usb_send_host_flag = 0;
    
}

/*********************************************************************
 * @fn      EP4_IN_Callback
 *
 * @brief  Endpoint 4 IN.
 *
 * @return  none
 */
void EP4_IN_Callback (void)
{ 
    
}

/*********************************************************************
 * @fn      EP4_OUT_Callback
 *
 * @brief  Endpoint 4 OUT.
 *
 * @return  none
 */
void EP4_OUT_Callback (void)
{ 
    uint16_t i;
    USB_Rx_Cnt = USB_SIL_Read(EP4_IN,HID_Buffer);
    for ( i = 0; i < USB_Rx_Cnt; i++)
    {
        HID_Buffer[i] = ~HID_Buffer[i];
    }
    USB_SIL_Write( EP4_OUT, HID_Buffer, USB_Rx_Cnt );
    SetEPTxValid( ENDP4 );
    SetEPRxValid( ENDP4 );
}

/*********************************************************************
 * @fn      USBD_ENDPx_DataUp
 *
 * @brief  USBD ENDPx DataUp Function
 * 
 * @param   endp - endpoint num.
 *          *pbuf - A pointer points to data.
 *          len - data length to transmit.
 * 
 * @return  data up status.
 */
uint8_t USBD_ENDPx_DataUp( uint8_t endp, uint8_t *pbuf, uint16_t len )
{
	if( endp == ENDP3 )
	{
		if (USBD_Endp3_Busy)
		{
			return USB_ERROR;
		}
		USB_SIL_Write( EP3_IN, pbuf, len );
		USBD_Endp3_Busy = 1;
		SetEPTxStatus( ENDP3, EP_TX_VALID );
	}
	else
	{
		return USB_ERROR;
	}
	return USB_SUCCESS;
}