//
// Created by epagris on 2022.11.03..
//

#include <memory.h>
#include <stdbool.h>
#include "ethernet_frame.h"
#include "../../utils.h"

#define ETH_ETHERTYPE_LENGTH_THRESHOLD (1500)
#define ETH_ETHERNET_HEADER_SIZE (14)

EthernetAddress ETH_ETHERNET_IPMC_HWADDR = { 0x01, 0x00, 0x5E, 0x00, 0x00, 0x00 };

int parse_ethernet(const uint8_t *hdr, uint32_t size, PcktHeaderElement *pcktHdrLe, struct EthInterface_ *intf) {
    EthernetProps * frameProps = (EthernetProps *) &pcktHdrLe->props;
    FETCH_ADVANCE(frameProps->destAddr, hdr, ETH_HW_ADDR_LEN); // copy destination address
    FETCH_ADVANCE(frameProps->sourceAddr, hdr, ETH_HW_ADDR_LEN); // copy destination address
    FETCH_WORD_H2N_ADVANCE(&frameProps->length_type, hdr); // copy length/type field

    // fill-in packet property header fields
    frameProps->validityOK = true;
    frameProps->containedPacketClass =
            frameProps->length_type <= ETH_ETHERTYPE_LENGTH_THRESHOLD ? 0 : frameProps->length_type;
    frameProps->headerSize = ETH_ETHERNET_HEADER_SIZE;

    return frameProps->containedPacketClass;
}

void insert_ethernet_header(uint8_t *hdr, const PcktHeaderElement *headers) {
    EthernetProps * ethProps = (EthernetProps *) &headers->props;
    FILL_ADVANCE(hdr, ethProps->destAddr, ETH_HW_ADDR_LEN);
    FILL_ADVANCE(hdr, ethProps->sourceAddr, ETH_HW_ADDR_LEN);
    FILL_WORD_H2N_ADVANCE(hdr, ethProps->length_type);
}