#include "arp_connblock.h"

#include <stddef.h>

#include "../packet_parsers/packet_parsers.h"
#include "../../utils.h"
#include "../../dynmem.h"
#include "../packet_parsers/arp_packet.h"

static bool filtArp(const PcktSieveFilterCondition * filtCond, const PcktProps * contProps, const PcktProps * ownProps, EthInterface * intf) {
    EthernetProps * ethProps = (EthernetProps *) contProps;
    ArpProps * arpProps = (ArpProps *) ownProps;

    return ethProps->length_type == ETH_ARP_PACKET_CLASS;
}

ConnBlock arp_new_connblock(EthInterface * intf, SieveCallBackFn cb) {
    ConnBlock arpConnB; // create ARP connblock

    PcktSieveFilterCondition filtCond;
    packfiltcond_zero(&filtCond);
    PcktSieveLayerTag tag;
    tag.p = intf;
    arpConnB.sieveLayer = packsieve_new_layer(&intf->sieve.layer0, &filtCond, false, filtArp, cb, tag, ETH_ARP_PACKET_CLASS);
    ASSERT_NULL(arpConnB.sieveLayer);

    arpConnB.sieve = &intf->sieve;
    arpConnB.sieveLayer->connBReportFn = arp_print_report;

    return arpConnB;
}

void arp_send(const ConnBlock * connBlock, const ArpProps * props) {
    // allocate header chain
    PcktHeaderElement * arpHeader = ALLOC_HEADER_ELEMENT(ArpProps);
    PcktHeaderElement * ethHeader = ALLOC_HEADER_ELEMENT(EthernetProps);
    arpHeader->next = NULL;
    arpHeader->prev = ethHeader;
    ethHeader->next = arpHeader;
    ethHeader->prev = NULL;

    // fetch props
    ArpProps * arpProps = HEADER_FETCH_PROPS(ArpProps, arpHeader);
    EthernetProps * ethProps = HEADER_FETCH_PROPS(EthernetProps, ethHeader);

    // ARP
    *arpProps = *props;

    // Ethernet
    ethProps->length_type = ETH_ARP_PACKET_CLASS;
    memset(ethProps->destAddr, 0xFF, ETH_HW_ADDR_LEN); // broadcast destination
    memcpy(ethProps->sourceAddr, connBlock->sieve->intf->mac, ETH_HW_ADDR_LEN); // source

    // allocate transmit buffer
    uint32_t txHeaderSize = ETH_ETHERNET_HEADER_SIZE + ETH_ARP_HEADER_SIZE;
    uint32_t txBufSize = MAX(txHeaderSize + 4, 60);
    uint8_t * txBuf = dynmem_alloc(txBufSize);

    // insert Ethernet header
    insert_ethernet_header(txBuf, ethHeader);

    // insert ARP header
    insert_arp_header(txBuf + ETH_ETHERNET_HEADER_SIZE, arpHeader);

    // release headers
    dynmem_free(arpHeader);
    dynmem_free(ethHeader);

    // append CRC at the end
    uint32_t crc = crc32(txBuf, txBufSize - 4);
    memcpy(txBuf + txBufSize - 4, &crc, 4);

    // send packet
    RawPckt rpckt;
    rpckt.size = txBufSize;
    rpckt.payload = txBuf;
    rpckt.time_s = 0;
    rpckt.time_ns = 0;
    ethinf_transmit(connBlock->sieve->intf, &rpckt);

    // release transmit buffer
    dynmem_free(txBuf);
}

void arp_print_report(const ConnBlock *connBlock) {
    INFO("ARP");
}