//
// Created by xemon on 05.05.2022.
//

#include "XfcProtEncoder.h"
#include "XfcProtCrc.h"
#include "XfcProtCommon.h"


////private
uint16_t XfcTransPackEncoderGetDataSegmentLength(tXfcProtEncoder *env) {
    return *((uint16_t *) (env->buffer->data + XFC_TRANSPORT_DATA_LEN_OFFSET));
}

////public
tXfcArray XfcTransPackEncoderGetDataSegmentAsArray(tXfcProtEncoder *env) {
    return (tXfcArray) {
            .data = env->buffer->data + XFC_TRANSPORT_HEADER_LEN,
            .begin = 0,
            .end = 0,
            .limit = env->buffer->limit - XFC_TRANSPORT_HEADER_LEN + XFC_TRANSPORT_CRC_LEN,
    };
}


void XfcTransPackEncoderSetId(tXfcProtEncoder *env, uint16_t id) {
    *((env->buffer->data + XFC_TRANSPORT_COMMAND_ID_OFFSET)) = id;
}

void XfcTransPackEncoderSetDataSegmentLength(tXfcProtEncoder *env, uint16_t dataSegmentLength) {
    *((uint16_t *) (env->buffer->data + XFC_TRANSPORT_DATA_LEN_OFFSET)) = dataSegmentLength;
}


void XfcTransPackEncoderFinalizeAndSignCrc(tXfcProtEncoder *env) {
    env->buffer->data[0] = env->magic;
    uint16_t dataLen = XfcTransPackEncoderGetDataSegmentLength(env);
    uint16_t crc = XfcProtCrc(env->buffer->data, dataLen + XFC_TRANSPORT_HEADER_LEN);
    *((uint16_t *) (env->buffer->data + XFC_TRANSPORT_HEADER_LEN + dataLen)) = crc;
    env->buffer->end = env->buffer->begin + dataLen + XFC_TRANSPORT_HEADER_LEN + XFC_TRANSPORT_CRC_LEN;
}