#!/bin/bash
# Test virtual machine for the built image (build/acpc2026.qcow2).
#
#   tests/check_vm.sh start [--wrong-clock] [--usb]   boot a throwaway copy
#   tests/check_vm.sh stop                              power it off, delete the copy
#
# The copy (tests/work/check.qcow2) opens SSH for the tests: password login,
# no DenyGroups, and the firewall accepts tcp 22. The built image itself is
# not modified. --wrong-clock starts with the hardware clock 3 hours behind
# (as on a lab machine running Windows), --usb adds a USB controller so that
# USB devices can be plugged in with tests/usb.sh.
set -eu
cd "$(dirname "$0")/.."
W=tests/work
MON=$W/monitor.sock
BUILT=$(realpath build/acpc2026.qcow2)
running() { pgrep -f "^qemu-system-x86_64 -name acpc2026-check" >/dev/null; }

case "${1:-}" in
start)
    shift
    running && { echo "The test VM is already running." >&2; exit 1; }
    mkdir -p "$W"
    qemu-img create -q -f qcow2 -b "$BUILT" -F qcow2 "$W/check.qcow2"
    for d in /usr/share/edk2/x64 /usr/share/OVMF /usr/share/edk2/ovmf; do
        for c in OVMF_CODE.4m.fd OVMF_CODE_4M.fd OVMF_CODE.fd; do
            [ -f "$d/$c" ] && { CODE=$d/$c; VARS=$d/${c/CODE/VARS}; break 2; }
        done
    done
    cp "$VARS" "$W/vars.fd"
    # Open SSH in the copy, offline
    touch "$W/fuse.raw"
    qemu-storage-daemon --blockdev driver=file,node-name=f,filename="$W/check.qcow2" \
        --blockdev driver=qcow2,node-name=q,file=f \
        --export type=fuse,id=e,node-name=q,mountpoint="$W/fuse.raw",writable=on > "$W/qsd.log" 2>&1 &
    for _ in $(seq 1 20); do mountpoint -q "$W/fuse.raw" && break; sleep 0.5; done
    start=$(sfdisk -J "$W/fuse.raw" | python3 -I -c 'import json,sys; p=json.load(sys.stdin)["partitiontable"]["partitions"]; print(max(p,key=lambda x:x["size"])["start"])')
    D="$W/fuse.raw?offset=$((start * 512))"
    printf 'PasswordAuthentication yes\n' > "$W/00-test.conf"
    w() { debugfs -w -R "$1" "$D" >/dev/null 2>&1 || true; }
    w "rm /etc/ssh/sshd_config.d/icpc.conf"
    w "write $W/00-test.conf /etc/ssh/sshd_config.d/00-test.conf"
    w "mkdir /etc/systemd/system/firewall.service.d"
    w "write tests/test-ssh.conf /etc/systemd/system/firewall.service.d/test-ssh.conf"
    for f in /etc/ssh/sshd_config.d/00-test.conf /etc/systemd/system/firewall.service.d/test-ssh.conf; do
        for x in "mode 0100644" "uid 0" "gid 0"; do w "set_inode_field $f $x"; done
    done
    for x in "mode 040755" "uid 0" "gid 0"; do w "set_inode_field /etc/systemd/system/firewall.service.d $x"; done
    fusermount3 -u "$W/fuse.raw"
    pkill -f "^qemu-storage-daemon .*$W/check.qcow2" || true
    sleep 1
    EXTRA=()
    for a in "$@"; do
        case "$a" in
            --wrong-clock) EXTRA+=(-rtc "base=$(date -u -d '-3 hours' +%Y-%m-%dT%H:%M:%S)") ;;
            --usb) EXTRA+=(-device qemu-xhci,id=xhci) ;;
        esac
    done
    setsid qemu-system-x86_64 -name acpc2026-check -machine q35,accel=kvm -cpu host -m 6144 -smp 4 \
        -drive if=pflash,format=raw,readonly=on,file="$CODE" \
        -drive if=pflash,format=raw,file="$W/vars.fd" \
        -drive id=disk0,file="$W/check.qcow2",format=qcow2,if=none \
        -device virtio-blk-pci,drive=disk0,bootindex=1 \
        -netdev user,id=net0,hostfwd=tcp:127.0.0.1:2222-:22 -device virtio-net-pci,netdev=net0 \
        -vga virtio -display none -monitor unix:"$MON",server,nowait \
        -serial file:"$W/serial.log" "${EXTRA[@]}" > "$W/qemu.log" 2>&1 &
    for _ in $(seq 1 120); do
        tests/vssh.sh team true 2>/dev/null && break
        sleep 3
    done
    # Wait for the desktop session of the team account
    for _ in $(seq 1 60); do
        tests/vssh.sh team 'loginctl list-sessions --no-legend' 2>/dev/null | grep -q seat0 && break
        sleep 2
    done
    echo "Test VM ready (SSH 127.0.0.1:2222, monitor $MON)."
    ;;
stop)
    if running; then
        python3 -I tests/monitor.py "$MON" quit || true
        for _ in $(seq 1 30); do running || break; sleep 1; done
    fi
    rm -rf "$W"
    echo "Test VM stopped."
    ;;
*)
    sed -n '2,12p' "$0" | sed 's/^# \{0,1\}//'
    exit 2
    ;;
esac