#!/usr/bin/env bash
# Launch or validate UHCI controller enumeration (P1-B) in QEMU.
#
# Topology under test:
#   -machine pc (i440fx/PIIX3 chipset) → -device piix3-usb-uhci,id=uhci
#     └─ bus=uhci.0 → usb-kbd
#
# Validates: pcid auto-spawns uhcid for the PIIX3 UHCI PCI device (class 0c0300,
# see local/config/drivers.d/20-usb.toml), uhcid maps the I/O base, initializes
# the frame list, and detects the attached usb-kbd (port connect + enumeration
# descriptor read). This is the P1-B UHCI runtime-enumeration proof that closes
# the P8-B gap for UHCI.
#
# Evidence is read from the serial log (no guest-side checker exists that
# validates UHCI enumeration specifically), mirroring the test-xhci-irq-qemu.sh
# proof style. Proof markers come straight from
# local/recipes/drivers/uhcid/source/src/main.rs:
#   "UHCI USB 1.1 at <pci_path>"                 (main.rs:487 — controller bound)
#   "uhcid: <name> controller initialized, polling ports" (main.rs:535 — init
#       done; note ctrl.name is interpolated, e.g. "uhcid: uhci0_uhci controller
#       initialized, polling ports", so the grep uses a regex, not a literal)
#   "uhcid: port <n> connect detected"            (main.rs:545 — port event)
#   "uhcid: port <n> device <vid>:<pid> class <c>" (main.rs:551 — enumerated)

set -euo pipefail

find_uefi_firmware() {
    local candidates=(
        "/usr/share/ovmf/x64/OVMF.4m.fd"
        "/usr/share/OVMF/x64/OVMF.4m.fd"
        "/usr/share/ovmf/x64/OVMF_CODE.4m.fd"
        "/usr/share/OVMF/x64/OVMF_CODE.4m.fd"
        "/usr/share/ovmf/OVMF.fd"
        "/usr/share/OVMF/OVMF_CODE.fd"
        "/usr/share/qemu/edk2-x86_64-code.fd"
    )
    local path
    for path in "${candidates[@]}"; do
        if [[ -f "$path" ]]; then
            printf '%s\n' "$path"
            return 0
        fi
    done
    return 1
}

usage() {
    cat <<'USAGE'
Usage: test-uhci-runtime-qemu.sh [--check] [config]

Boot or validate UHCI (USB 1.1) controller enumeration on a Red Bear image in
QEMU. The PIIX3 UHCI companion controller only exists on the i440fx machine
type, so this proof uses `-machine pc` rather than the q35 machine used by the
xHCI suite. Defaults to redbear-mini (mapped to the in-tree redbear-mini image).
USAGE
}

check_mode=0
config="redbear-mini"
for arg in "$@"; do
    case "$arg" in
        --help|-h|help)
            usage
            exit 0
            ;;
        --check)
            check_mode=1
            ;;
        redbear-*)
            config="$arg"
            ;;
    esac
done

firmware="$(find_uefi_firmware)" || {
    echo "ERROR: no usable x86_64 UEFI firmware found" >&2
    exit 1
}

arch="${ARCH:-$(uname -m)}"
# Prefer the live ISO (canonical build-redbear.sh artifact); harddrive.img is
# only produced by older make-all flows and goes stale, which would test the
# wrong tree. extra.img stays as a data drive in both modes.
iso="build/$arch/$config.iso"
image="build/$arch/$config/harddrive.img"
extra="build/$arch/$config/extra.img"

boot_media=""
if [[ -f "$iso" ]]; then
    boot_media="iso"
elif [[ -f "$image" ]]; then
    boot_media="harddrive"
else
    echo "ERROR: no bootable image found ($iso or $image)" >&2
    echo "Build it first with: ./local/scripts/build-redbear.sh $config" >&2
    exit 1
fi

if [[ ! -f "$extra" ]]; then
    truncate -s 1g "$extra"
fi

if [[ "$boot_media" == "iso" ]]; then
    boot_args=(-cdrom "$iso")
else
    boot_args=(-drive file="$image",format=raw,if=none,id=drv0,snapshot=on -device nvme,drive=drv0,serial=NVME_SERIAL)
fi

pkill -f "qemu-system-x86_64.*$config" 2>/dev/null || true
sleep 1

if [[ "$check_mode" -eq 1 ]]; then
    log_file="build/$arch/$config/uhci-runtime-check.log"
    rm -f "$log_file"
    set +e
    # 180s mirrors the xHCI interrupt proof budget. UHCI enumeration on QEMU's
    # emulated PIIX3 is quick once uhcid spawns, but the guest clock runs several
    # times slower than wall under boot load (same characteristic latency noted
    # in test-usb-hub-qemu.sh).
    timeout 180s qemu-system-x86_64 \
      -name "Red Bear OS x86_64" \
      -machine pc \
      -device piix3-usb-uhci,id=uhci \
      -device usb-kbd,bus=uhci.0 \
      -smp 4 \
      -m 2048 \
      -bios "$firmware" \
      -chardev stdio,id=debug,signal=off,mux=on \
      -serial chardev:debug \
      -mon chardev=debug \
      -device virtio-net,netdev=net0 \
      -netdev user,id=net0 \
      -object filter-dump,id=f1,netdev=net0,file="build/$arch/$config/network.pcap" \
      -nographic -vga none \
      "${boot_args[@]}" \
      -drive file="$extra",format=raw,if=none,id=drv1,snapshot=on \
      -device nvme,drive=drv1,serial=NVME_EXTRA \
      -enable-kvm -cpu host \
      > "$log_file" 2>&1
    status=$?
    set -e

    # 1. uhcid bound the controller and logged its PCI path. This proves pcid
    #    matched the PIIX3 UHCI PCI class (0c0300) and spawned uhcid.
    if ! grep -q "UHCI USB 1.1 at " "$log_file"; then
        echo "ERROR: uhcid did not bind the UHCI controller" >&2
        echo "       Expected: 'UHCI USB 1.1 at <pci_path>'" >&2
        grep -i "uhcid\|UHCI" "$log_file" | tail -10 >&2 || true
        echo "       See $log_file" >&2
        exit 1
    fi

    # 2. Frame list allocated and the polling loop started.
    if ! grep -Eq 'uhcid: .* controller initialized, polling ports' "$log_file"; then
        echo "ERROR: uhcid did not finish controller initialization" >&2
        echo "       Expected: 'uhcid: <name> controller initialized, polling ports'" >&2
        echo "       (main.rs:535 interpolates ctrl.name, e.g. 'uhcid: uhci0_uhci controller initialized, polling ports')" >&2
        echo "       See $log_file" >&2
        exit 1
    fi

    # 3. Port connect detected for the attached usb-kbd. This is the
    #    enumeration-proof marker: the controller saw a device and ran the
    #    descriptor-read path.
    if ! grep -Eq "uhcid: port [0-9]+ connect detected" "$log_file"; then
        echo "ERROR: uhcid did not detect a port connect event" >&2
        echo "       Expected: 'uhcid: port <n> connect detected'" >&2
        echo "       See $log_file" >&2
        exit 1
    fi

    # 4. No panics anywhere in the boot.
    if grep -qiE "panic|RUST_BACKTRACE" "$log_file"; then
        echo "ERROR: panic detected in boot log" >&2
        grep -iE "panic|RUST_BACKTRACE" "$log_file" | head -5 >&2
        echo "       See $log_file" >&2
        exit 1
    fi

    echo "UHCI_DRIVER=uhcid"
    echo "UHCI_CONTROLLER=piix3-usb-uhci"
    echo "UHCI_MACHINE=pc"
    echo "UHCI_LOG=$log_file"
    echo "UHCI controller enumeration confirmed in $log_file"
    exit 0
fi

exec qemu-system-x86_64 \
  -name "Red Bear OS x86_64" \
  -machine pc \
  -device piix3-usb-uhci,id=uhci \
  -device usb-kbd,bus=uhci.0 \
  -smp 4 \
  -m 2048 \
  -bios "$firmware" \
  -chardev stdio,id=debug,signal=off,mux=on \
  -serial chardev:debug \
  -mon chardev=debug \
  -device virtio-net,netdev=net0 \
  -netdev user,id=net0 \
  -object filter-dump,id=f1,netdev=net0,file="build/$arch/$config/network.pcap" \
  -vga std \
  "${boot_args[@]}" \
  -drive file="$extra",format=raw,if=none,id=drv1,snapshot=on \
  -device nvme,drive=drv1,serial=NVME_EXTRA \
  -enable-kvm -cpu host