/*
 * Copyright (c) 2006-2020, RT-Thread Development Team
 *
 * SPDX-License-Identifier: Apache-2.0
 *
 * Change Logs:
 * Date           Author       Notes
 * 2020-09-29     liuya       the first version
 */

#include "vklink.h"
#include <my_crc.h>
#include <string.h>

/**
 * @brief VK link 消息字节解析
 *
 * @param msg 消息结构体指针
 * @param data 待解析的字节
 * @return int 0-未收到一帧 1-收到一帧 -1-校验错误
 */
int VKlink_ParseChar(VKlink_Msg_Type *msg, uint8_t data)
{
    int ret_val = 0;

    switch (msg->rx_stage)
    {
    case VKLINK_RX_HEAD:
        if (VKLINK_MSG_HEAD == data)
        {
            msg->head = VKLINK_MSG_HEAD;
            msg->rx_stage = VKLINK_RX_PAYLOAD_LEN;
        }
        break;

    case VKLINK_RX_PAYLOAD_LEN:
        if (data <= sizeof(msg->payload))
        {
            msg->payload_len = data;
            msg->rx_stage = VKLINK_RX_SEQ;
        }
        else
        {
            msg->rx_stage = VKLINK_RX_HEAD;
        }
        break;

    case VKLINK_RX_SEQ:
        msg->seq = data;
        msg->rx_stage = VKLINK_RX_SYSID;

        break;

    case VKLINK_RX_SYSID:
        msg->sysid = data;
        msg->rx_stage = VKLINK_RX_COMPID;

        break;

    case VKLINK_RX_COMPID:
        msg->compid = data;
        msg->rx_stage = VKLINK_RX_MSGID;

        break;

    case VKLINK_RX_MSGID:
        msg->msgid = data;
        if (msg->payload_len > 0)
            msg->rx_stage = VKLINK_RX_PAYLOAD;
        else
            msg->rx_stage = VKLINK_RX_CHECK_LOW;
        msg->payload_rx_index = 0;

        break;

    case VKLINK_RX_PAYLOAD:
        msg->payload[msg->payload_rx_index++] = data;
        if (msg->payload_rx_index >= msg->payload_len)
        {
            msg->rx_stage = VKLINK_RX_CHECK_LOW;
            msg->payload_rx_index = 0;
        }
        break;

    case VKLINK_RX_CHECK_LOW:
        msg->crc16_check = data;
        msg->rx_stage = VKLINK_RX_CHECK_HIGH;

        break;

    case VKLINK_RX_CHECK_HIGH:
    {
        msg->crc16_check += ((uint16_t)data << 8);

        uint16_t crc_check =
            crc16_cyc_cal(0xFFFF, &msg->head, sizeof(msg->head));
        crc_check = crc16_cyc_cal(crc_check, &msg->payload_len,
                                  sizeof(msg->payload_len));
        crc_check = crc16_cyc_cal(crc_check, &msg->seq, sizeof(msg->seq));
        crc_check = crc16_cyc_cal(crc_check, &msg->sysid, sizeof(msg->sysid));
        crc_check = crc16_cyc_cal(crc_check, &msg->compid, sizeof(msg->compid));
        crc_check = crc16_cyc_cal(crc_check, &msg->msgid, sizeof(msg->msgid));
        crc_check = crc16_cyc_cal(crc_check, msg->payload, msg->payload_len);

        if (msg->crc16_check == crc_check)
        {
            ret_val = 1;
        }
        else
        {
            ret_val = -1;
        }
        msg->rx_stage = VKLINK_RX_HEAD;
    }
    break;

    default:
        msg->rx_stage = VKLINK_RX_HEAD;
        break;
    }

    return ret_val;
}

/**
 * @brief 往消息中填入数据
 *
 * @param pdata 需要填入的数据指针
 * @param len
 */
int vklink_msg_payload_put_data(VKlink_Msg_Type *msg, const void *pdata,
                                uint8_t len)
{
    int ret_val = 0;

    const uint8_t *data = (const uint8_t *)pdata;

    for (uint32_t i = 0; i < len; ++i)
    {
        if (data)
        {
            msg->payload[msg->payload_len] = data[i];
        }
        else
        {
            msg->payload[msg->payload_len] = 0;
        }

        msg->payload_len++;
        ret_val++;

        /* 如果超过了最大 payload 长度，则返回 -1 */
        if (msg->payload_len > VKLINK_MSG_PAYLOAD_MAX_LEN)
        {
            ret_val = -1;
            break;
        }
    }

    return ret_val;
}

/**
 * @brief 将消息逐字节的放入一个buff中
 *
 * @param msg 消息指针
 * @param pTxBuf buff 指针
 * @return uint32_t 消息占用的总字节数
 */
uint32_t VKlink_MsgTxFormat(const VKlink_Msg_Type *msg, uint8_t *pTxBuf)
{
    uint32_t index = 0;

    memcpy(pTxBuf + index, &msg->head, sizeof(msg->head));
    index += sizeof(msg->head);

    memcpy(pTxBuf + index, &msg->payload_len, sizeof(msg->payload_len));
    index += sizeof(msg->payload_len);

    memcpy(pTxBuf + index, &msg->seq, sizeof(msg->seq));
    index += sizeof(msg->seq);

    memcpy(pTxBuf + index, &msg->sysid, sizeof(msg->sysid));
    index += sizeof(msg->sysid);

    memcpy(pTxBuf + index, &msg->compid, sizeof(msg->compid));
    index += sizeof(msg->compid);

    memcpy(pTxBuf + index, &msg->msgid, sizeof(msg->msgid));
    index += sizeof(msg->msgid);

    memcpy(pTxBuf + index, msg->payload, msg->payload_len);
    index += msg->payload_len;

    uint16_t check = crc16_cyc_cal(0xFFFF, pTxBuf, index);

    memcpy(pTxBuf + index, &check, sizeof(check));
    index += sizeof(check);

    return index;
}