/*
 * Copyright 2017-present Open Networking Foundation
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef __PARSERS__
#define __PARSERS__

#include "headers.p4"
#include "defines.p4"

parser parser_impl(packet_in packet,
                  out headers_t hdr,
                  inout local_metadata_t local_metadata,
                  inout standard_metadata_t standard_metadata) {

    state start {
        transition select(standard_metadata.ingress_port) {
            CPU_PORT: parse_packet_out;
            default: parse_ethernet;
        }
    }

    state parse_packet_out {
        packet.extract(hdr.packet_out);
        transition parse_ethernet;
    }

    state parse_ethernet {
        packet.extract(hdr.ethernet);
        transition select(hdr.ethernet.ether_type) {
            ETH_TYPE_IPV4: parse_ipv4;
            default: accept;
        }
    }

    state parse_ipv4 {
        packet.extract(hdr.ipv4);
        transition select(hdr.ipv4.protocol) {
            IP_PROTO_TCP: parse_tcp;
            IP_PROTO_UDP: parse_udp;
            default: accept;
        }
    }

    state parse_tcp {
        packet.extract(hdr.tcp);
        local_metadata.l4_src_port = hdr.tcp.src_port;
        local_metadata.l4_dst_port = hdr.tcp.dst_port;
        transition accept;
    }

    state parse_udp {
        packet.extract(hdr.udp);
        local_metadata.l4_src_port = hdr.udp.src_port;
        local_metadata.l4_dst_port = hdr.udp.dst_port;
        transition accept;
    }
}

control deparser(packet_out packet, in headers_t hdr) {
    apply {
        packet.emit(hdr.packet_in);
        packet.emit(hdr.ethernet);
        packet.emit(hdr.ipv4);
        packet.emit(hdr.tcp);
        packet.emit(hdr.udp);
    }
}

#endif