#!/bin/bash
# vmix unattended macOS install, run by the PE hook (pe.sh) as root in the
# Recovery with /Volumes/VMIX mounted (V). Needs vmix.conf: TARGET_BYTES,
# PKG_BYTES, PKG_DISK_BYTES, APP_NAME, VOLUME_NAME.
#  1. find the target disk and the SharedSupport (InstallAssistant.pkg) disk by size
#  2. erase the target as APFS, unpack the installer app, dd the whole pkg into it
#     as SharedSupport.dmg (a "pkgdmg", startosinstall checks its koly footer)
#  3. startosinstall prepares, then reboots itself into the install phase; the
#     installed system's first boot ends at the loginwindow (the host powers off)
# Never returns on success; a return means failure (the PE records the status).
set -x
. "$V/pe-lib.sh"
fail() {
  echo "VMIX-FAIL: $*"
  cp /var/log/install.log "$V/system-install.log" 2>/dev/null
  sync
  exit 1
}
# each boot into the PE with the install still pending is one attempt
ATTEMPT=$(( $(cat "$V/install.attempt" 2>/dev/null || echo 0) + 1 ))
echo "$ATTEMPT" > "$V/install.attempt"; sync
echo "VMIX-INSTALL: attempt $ATTEMPT (boot into the PE)"
[ "$ATTEMPT" -le 3 ] || fail "the installer keeps coming back to the PE ($ATTEMPT boots)"

# --- 1. disks by exact size
disk_by_size() {
  for d in $(diskutil list | grep -oE '^/dev/disk[0-9]+' | sort -u); do
    if [ "$(diskutil info "$d" | sed -n 's/.*Disk Size:.*(\([0-9]*\) Bytes).*/\1/p')" = "$1" ]; then
      echo "${d#/dev/}"; return 0
    fi
  done
  return 1
}
TARGET=$(disk_by_size "$TARGET_BYTES") || fail "target disk of $TARGET_BYTES bytes not found"
SSDISK=$(disk_by_size "$PKG_DISK_BYTES") || fail "SharedSupport disk of $PKG_DISK_BYTES bytes not found"
echo "VMIX-INSTALL: target=$TARGET sharedsupport=$SSDISK"

# --- 2. target volume + installer app (the pkg payload skeleton + SharedSupport.dmg)
VOL="/Volumes/$VOLUME_NAME"
APP="$VOL/$APP_NAME"
SS="$APP/Contents/SharedSupport/SharedSupport.dmg"
prepare_target() {
  diskutil eraseDisk APFS "$VOLUME_NAME" GPT "$TARGET" || fail "eraseDisk"
  [ -d "$VOL" ] || fail "$VOL not mounted after erase"
  tar -xf "$V/installer-app.tar" -C "$VOL" || fail "untar installer app"
  [ -x "$APP/Contents/Resources/startosinstall" ] || fail "startosinstall missing from $APP"
  mkdir -p "$APP/Contents/SharedSupport"
  FULL=$(( PKG_BYTES / 1048576 )); REM=$(( PKG_BYTES % 1048576 ))
  echo "VMIX-INSTALL: copying SharedSupport.dmg ($PKG_BYTES bytes) from /dev/r$SSDISK"
  dd if="/dev/r$SSDISK" of="$SS" bs=1048576 count=$FULL || fail "dd SharedSupport"
  [ "$REM" -gt 0 ] && { dd if="/dev/r$SSDISK" bs=1048576 skip=$FULL count=1 | dd bs=1 count=$REM >> "$SS"; } || true
  [ "$(stat -f %z "$SS")" = "$PKG_BYTES" ] || fail "SharedSupport.dmg size $(stat -f %z "$SS") != $PKG_BYTES"
  tail -c 512 "$SS" | grep -qa koly || fail "SharedSupport.dmg has no koly footer"
  chflags -h norestricted "$SS" 2>/dev/null || true
  sync
}
prepare_target
SOI="$APP/Contents/Resources/startosinstall"
echo "VMIX-INSTALL: app ready, clock $(date -u)"

# Offline install: no NIC is attached. Blackhole Apple's install/verify endpoints
# too, so osinstallersetupd's requests fail immediately instead of timing out.
for d in swscan.apple.com swcdn.apple.com swdist.apple.com swquery.apple.com \
         gs.apple.com gsa.apple.com gdmf.apple.com mesu.apple.com xp.apple.com \
         albert.apple.com captive.apple.com deviceservices-external.apple.com \
         identity.apple.com ppq.apple.com crl.apple.com ocsp.apple.com \
         ocsp2.apple.com valid.apple.com; do
  echo "127.0.0.1 $d" >> /etc/hosts
done

# --- 3. startosinstall prepares (~5 min) then reboots the machine itself into the
# install phase; it never returns on success. Prepare is intermittently slow in
# QEMU, so an attempt that stalls or runs too long is killed and retried on a
# freshly erased target.
run_soi() { "$SOI" --volume "$VOL" --agreetolicense --nointeraction --rebootdelay 5 "$@"; }
free_kb() { df -k "$VOL" 2>/dev/null | awk 'NR==2 {print $4}'; }
try=0
while [ "$try" -lt 6 ]; do
  try=$((try + 1))
  [ "$try" -gt 1 ] && prepare_target
  echo "VMIX-INSTALL: startosinstall try $try"
  run_soi 2>&1 &
  SOI_PID=$!
  last=$(free_kb); stalled=0; elapsed=0
  while kill -0 "$SOI_PID" 2>/dev/null; do
    sleep 30; elapsed=$((elapsed + 30))
    now=$(free_kb)
    if [ "$now" = "$last" ]; then stalled=$((stalled + 30)); else stalled=0; last=$now; fi
    [ $((elapsed % 120)) -eq 0 ] && echo "VMIX-INSTALL: prepare running ${elapsed}s (stalled ${stalled}s)"
    if [ "$stalled" -ge 240 ] || [ "$elapsed" -ge 600 ]; then
      echo "VMIX-INSTALL: prepare too slow (stalled=${stalled}s elapsed=${elapsed}s), killing to retry"
      kill -9 "$SOI_PID" 2>/dev/null; pkill -9 -f startosinstall 2>/dev/null
      break
    fi
  done
  wait "$SOI_PID" 2>/dev/null
  echo "VMIX-INSTALL: startosinstall try $try ended without rebooting"
  sleep 3
done
fail "startosinstall did not complete after $try tries"