/*
 * Tencent is pleased to support the open source community by making IoT Hub
 available.
 * Copyright (C) 2019 THL A29 Limited, a Tencent company. All rights reserved.

 * Licensed under the MIT License (the "License"); you may not use this file
 except in
 * compliance with the License. You may obtain a copy of the License at
 * http://opensource.org/licenses/MIT

 * Unless required by applicable law or agreed to in writing, software
 distributed under the License is
 * distributed on an "AS IS" basis, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 KIND,
 * either express or implied. See the License for the specific language
 governing permissions and
 * limitations under the License.
 *
 */

#include "utils_ringbuff.h"

#include <stdio.h>
#include <string.h>

int ring_buff_init(sRingbuff *ring_buff, char *buff, uint32_t size)
{
    ring_buff->buffer     = buff;
    ring_buff->size       = size;
    ring_buff->readpoint  = 0;
    ring_buff->writepoint = 0;
    memset(ring_buff->buffer, 0, ring_buff->size);
    ring_buff->full = false;

    return RINGBUFF_OK;
}

int ring_buff_flush(sRingbuff *ring_buff)
{
    ring_buff->readpoint  = 0;
    ring_buff->writepoint = 0;
    memset(ring_buff->buffer, 0, ring_buff->size);
    ring_buff->full = false;

    return RINGBUFF_OK;
}

int ring_buff_push_data(sRingbuff *ring_buff, uint8_t *pData, int len)
{
    int i;

    if (len > ring_buff->size) {
        return RINGBUFF_TOO_SHORT;
    }

    for (i = 0; i < len; i++) {
        if (((ring_buff->writepoint + 1) % ring_buff->size) == ring_buff->readpoint) {
            ring_buff->full = true;
            return RINGBUFF_FULL;
        } else {
            if (ring_buff->writepoint < (ring_buff->size - 1)) {
                ring_buff->writepoint++;
            } else {
                ring_buff->writepoint = 0;
            }
            ring_buff->buffer[ring_buff->writepoint] = pData[i];
        }
    }

    return RINGBUFF_OK;
}

int ring_buff_pop_data(sRingbuff *ring_buff, uint8_t *pData, int len)
{
    int i;

    if (len > ring_buff->size) {
        return RINGBUFF_TOO_SHORT;
    }

    for (i = 0; i < len; i++) {
        if (ring_buff->writepoint == ring_buff->readpoint) {
            break;
        } else {
            if (ring_buff->readpoint == (ring_buff->size - 1)) {
                ring_buff->readpoint = 0;
            }

            else {
                ring_buff->readpoint++;
            }
            pData[i] = ring_buff->buffer[ring_buff->readpoint];
        }
    }

    return i;
}