sciparse 0.6.1

// Copyright 2026 Anapaya Systems
//
// 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.

//! Exhaustive exerciser for [`ScionRawPacketView`] and typed packet views.

#![allow(dead_code, unused_imports)]

use super::{black_box, header, payload, read_slice_bounds, touch_slice_bounds};
use crate::{
    core::view::View,
    packet::{
        classify::ClassifiedPacketView,
        view::{ScionRawPacketView, ScionScmpPacketView, ScionUdpPacketView},
    },
    payload::{scmp::view::ScmpPayloadView, udp::view::UdpDatagramView},
};

/// Exercises every getter and setter on a [`ScionRawPacketView`] and all
/// reachable sub-views (header, path, payload).
///
/// Aggressively attempts to construct every typed view regardless of the
/// `next_header` field. A view that successfully constructs must be safe
/// to access — if it isn't, that's a bug we want to catch.
pub fn exec_every_view_function(view: &mut ScionRawPacketView) {
    // ── Packet-level accessors ────────────────────────────────────────
    read_slice_bounds(view.payload());
    touch_slice_bounds(view.payload_mut());
    read_slice_bounds(view.as_slice());

    // ── Header sub-view ───────────────────────────────────────────────
    black_box(view.header());
    header::exec_every_view_function(view.header_mut());

    // ── Classification ────────────────────────────────────────────────

    if let Ok(class) = view.try_classify() {
        black_box(class.dst_socket_addr());

        match class {
            ClassifiedPacketView::Udp(udp_view) => {
                exec_udp_packet_view(udp_view);
            }
            ClassifiedPacketView::Scmp(scmp_view) => {
                exec_scmp_packet_view(scmp_view);
            }
            ClassifiedPacketView::Other(_raw) => {}
        }
    }

    // ── Try every typed view regardless of next_header ────────────────
    // If construction succeeds the view MUST be safe to use. Exercise
    // everything we can on it to surface any out-of-bounds access.

    // Immutable UDP
    if let Ok((udp_view, _rest)) = ScionUdpPacketView::try_from_slice(view.as_slice()) {
        exec_udp_packet_view(udp_view);
    }
    // Immutable SCMP
    if let Ok((scmp_view, _rest)) = ScionScmpPacketView::try_from_slice(view.as_slice()) {
        exec_scmp_packet_view(scmp_view);
    }

    // Mutable UDP
    unsafe {
        if let Ok((udp_view_mut, _rest)) =
            ScionUdpPacketView::try_from_mut_slice(view.as_slice_mut())
        {
            exec_udp_packet_view_mut(udp_view_mut);
        }
    }

    // Mutable SCMP
    unsafe {
        if let Ok((scmp_view_mut, _rest)) =
            ScionScmpPacketView::try_from_mut_slice(view.as_slice_mut())
        {
            exec_scmp_packet_view_mut(scmp_view_mut);
        }
    }
}

/// Exercises getters on an immutable [`ScionUdpPacketView`].
fn exec_udp_packet_view(view: &ScionUdpPacketView) {
    black_box(view.header());
    read_slice_bounds(view.payload());
    read_slice_bounds(view.as_slice());

    let udp = view.udp();
    black_box(udp.src_port());
    black_box(udp.dst_port());
    black_box(udp.length());
    black_box(udp.checksum());
    read_slice_bounds(udp.payload());
    read_slice_bounds(udp.as_slice());

    // Round-trip back to raw
    let raw = view.as_raw();
    black_box(raw.header());
    read_slice_bounds(raw.payload());
    read_slice_bounds(raw.as_slice());
}

/// Exercises getters and setters on a mutable [`ScionUdpPacketView`].
fn exec_udp_packet_view_mut(view: &mut ScionUdpPacketView) {
    exec_udp_packet_view(view);

    header::exec_every_view_function(view.header_mut());

    // Exercise the UDP payload through the mutable typed view
    {
        let udp = view.udp();
        payload::udp::exec_every_view_function_ref(udp);
    }

    let raw = view.as_raw_mut();
    touch_slice_bounds(raw.payload_mut());
}

/// Exercises getters on an immutable [`ScionScmpPacketView`].
fn exec_scmp_packet_view(view: &ScionScmpPacketView) {
    black_box(view.header());
    read_slice_bounds(view.payload());
    read_slice_bounds(view.as_slice());

    let scmp = view.scmp();
    black_box(scmp.message_type());
    black_box(scmp.code());
    black_box(scmp.checksum());
    black_box(scmp.dst_port());
    black_box(scmp.message());
    read_slice_bounds(scmp.as_slice());

    // Round-trip back to raw
    let raw = view.as_raw();
    black_box(raw.header());
    read_slice_bounds(raw.payload());
    read_slice_bounds(raw.as_slice());
}

/// Exercises getters and setters on a mutable [`ScionScmpPacketView`].
fn exec_scmp_packet_view_mut(view: &mut ScionScmpPacketView) {
    exec_scmp_packet_view(view);

    header::exec_every_view_function(view.header_mut());

    // Exercise the SCMP payload through the mutable typed view
    {
        let scmp = view.scmp();
        black_box(scmp.message_type());
        black_box(scmp.code());
        black_box(scmp.checksum());
        black_box(scmp.dst_port());
        black_box(scmp.message());
    }

    // Safety: we don't mutate in a way that invalidates the view.
    let raw = unsafe { view.as_raw_mut() };
    touch_slice_bounds(raw.payload_mut());
}