/*
 * data_buffer.c
 *
 *  Created on: 20-Jun-2023
 *      Author: vivek
 */


#include <stdint.h>
#include <string.h>
#include "descriptor_fifo.h"

int descriptor_fifo_write(uint32_t descriptor_data_size,
		uint32_t* descrtiptor_data)
{
	if(descriptor_data_size == 0x00)
	{
		return -2;
	}

	for(uint32_t i=0;i<(descriptor_data_size);i++)
	{
		if(ltcusb_fifo_write(DESC_FIFO_ADDR_RV, descrtiptor_data[i]) != 0)
		{
			return -1;
		}
	}

	return 0;
}

static int ascii2unicode(uint8_t* ascii_str, uint32_t ascii_str_len,
		uint8_t* unicode_str, uint32_t* unicode_str_len)
{
	*unicode_str_len = (ascii_str_len << 1);

	for(uint32_t i=0;i<*unicode_str_len;i++)
	{
		unicode_str[i] = (i&0x1)?0:(uint8_t)ascii_str[i/2];
	}

	return 0;
}

int create_string_descriptor(uint8_t* str, uint32_t str_len, uint32_t* str_desc, uint32_t* str_desc_len)
{
	const uint32_t unicode_max_len = 252;
	uint8_t unicode_str[unicode_max_len];

	memset(unicode_str,0x00,unicode_max_len);

	if(str_len > unicode_max_len/2)
	{
		return -1;
	}

	ascii2unicode(str, str_len, unicode_str, str_desc_len);

	*str_desc_len += 2;

	/**@todo descriptor type with enum or macro.*/
	*str_desc = (uint32_t)*str_desc_len | (uint32_t)(0x03 << 8);

	memcpy((uint8_t*)str_desc+2, unicode_str, *str_desc_len-2);

	if(*str_desc_len%4)
	{
		*str_desc_len = (*str_desc_len >> 2);
		++*str_desc_len;
	}
	else
	{
		*str_desc_len = (*str_desc_len >> 2);
	}


	return 0;
}