#include <stddef.h>
#include "global_state.h"
#include "dynmem.h"

#include "prefab/prefab.h"
#include "packet_sieve.h"
#include "prefab/packet_parsers/arp_packet.h"
#include "prefab/packet_parsers/icmp_packet.h"
#include "etherlib/prefab/packet_parsers/igmp_packet.h"
#include "etherlib/prefab/packet_parsers/tcp_segment.h"
#include "utils.h"

EthState gEthState = { 0 };

static void register_packet_parsers() {
    PcktClassDesc cdesc;
    // Ethernet frame parser
    cdesc.class = 0;
    cdesc.containerClass = 0;
    cdesc.procFun = parse_ethernet;
    cdesc.hdrInsFn = insert_ethernet_header;
    cdesc.propertySize = sizeof(EthernetProps);
    packreg_add_class(E.pcktReg, &cdesc);

    // IPv4 packet parser
    cdesc.class = ETH_IPv4_PACKET_CLASS;
    cdesc.containerClass = 0;
    cdesc.procFun = parse_ipv4;
    cdesc.hdrInsFn = insert_ipv4_header;
    cdesc.propertySize = sizeof(IPv4Props);
    packreg_add_class(E.pcktReg, &cdesc);

    // UDP packet parser
    cdesc.class = ETH_UDP_PACKET_CLASS;
    cdesc.containerClass = ETH_IPv4_PACKET_CLASS;
    cdesc.procFun = parse_udp;
    cdesc.hdrInsFn = insert_udp_header;
    cdesc.propertySize = sizeof(UdpProps);
    packreg_add_class(E.pcktReg, &cdesc);

    // ARP packet parser
    cdesc.class = ETH_ARP_PACKET_CLASS;
    cdesc.containerClass = 0;
    cdesc.procFun = parse_arp;
    cdesc.hdrInsFn = insert_arp_header;
    cdesc.propertySize = sizeof(ArpProps);
    packreg_add_class(E.pcktReg, &cdesc);

    // ICMP packet parser
    cdesc.class = ETH_ICMP_PACKET_CLASS;
    cdesc.containerClass = ETH_IPv4_PACKET_CLASS;
    cdesc.procFun = parse_icmp;
    cdesc.hdrInsFn = insert_icmp_header;
    cdesc.propertySize = sizeof(IcmpProps);
    packreg_add_class(E.pcktReg, &cdesc);

    // IGMP packet parser
    cdesc.class = ETH_IGMP_PACKET_CLASS;
    cdesc.containerClass = ETH_IPv4_PACKET_CLASS;
    cdesc.procFun = parse_igmp;
    cdesc.hdrInsFn = insert_igmp_header;
    cdesc.propertySize = sizeof(IgmpProps);
    packreg_add_class(E.pcktReg, &cdesc);

    // TCP packet parser
    cdesc.class = ETH_TCP_PACKET_CLASS;
    cdesc.containerClass = ETH_IPv4_PACKET_CLASS;
    cdesc.procFun = parse_tcp;
    cdesc.hdrInsFn = insert_tcp_header;
    cdesc.propertySize = sizeof(TcpProps);
    packreg_add_class(E.pcktReg, &cdesc);
}

void ethlib_init() {
    dynmem_init(); // initialize dynamic memory subsystem
    E.tmr = timer_new(ETHLIB_TMR_SCHED_TABLE_SIZE); // create timer
    E.cbdt = cbdt_new(ETHLIB_CBD_TABLE_SIZE); // create a new connection block descriptor table
    E.pcktReg = packreg_new(); // create new packet registry
    register_packet_parsers(); // register packet parsers

    //E.ethIntf = ethintf_new(); // create new Ethernet interface
}

void close_connection(cbd d) {
    ConnBlock connBlock;
    if (!cbdt_get_connection_block(E.cbdt, d, &connBlock)) {
        ERROR("Invalid CBD descriptor: '%d'!\n", d);
        return;
    }

    cbdt_release(E.cbdt, d); // release from CBD table

    connb_remove(&connBlock); // remove connection block
}

EthInterface *get_default_interface() {
    return E.ethIntf;
}

EthInterface * get_interface_by_address(ip4_addr addr) {
    return get_default_interface();
}