echo "Remove Omarchy 3 power udev rules that run a command out of a user home"

rules_dir="${OMARCHY_UDEV_RULES_DIR:-/etc/udev/rules.d}"
reload_needed_marker="${OMARCHY_UDEV_RELOAD_NEEDED_MARKER:-/var/lib/omarchy/migrations/1787946619-udev-reload-needed}"
udev_control="${OMARCHY_UDEV_CONTROL:-/run/udev/control}"

as_root() {
  if (( EUID == 0 )); then
    "$@"
  else
    sudo "$@"
  fi
}

# Omarchy 3 generated these two rules with an unquoted heredoc, so the installing
# user's $HOME was expanded and the file on disk names that absolute home path.
# udev runs RUN+= as root, and
# ~/.local/share/omarchy is a symlink that same unprivileged user owns: replacing
# it with a tree of their own and provoking a power_supply event runs their code
# as root. Quattro ships the rules as 99-omarchy-*.rules under /usr/bin, but the
# one-shot migration that swept the old filenames was itself dropped, so an
# install that came up through the 3.x line keeps the old file until this
# migration removes it.
#
# Pre-4 layout work normally belongs in the Omarchy 4 upgrade command, but that
# command only runs on a machine still making the crossing, so an install that
# crossed already would never see it. The upgrade command ends by running
# omarchy-migrate, so this covers the installs still to upgrade as well.
#
# Only remove a file that is actually one of those. A comment is inert to udev,
# so the match keys on an active RUN+= whose command really is the legacy path
# under a home directory for that filename's binary. A rule of the same name that
# a user wrote themselves survives, including one that merely mentions the legacy
# path in a comment, and so does a legacy file already repointed at /usr/bin.
rule_runs_from_home() {
  local file="$1" binary="$2"
  local pattern="^/.+/\\.local/share/omarchy/bin/$binary\$"
  local line logical="" rest command word
  local -a words

  while IFS= read -r line || [[ -n $line ]]; do
    # udev tests for a comment before it joins continuations, and skipping one
    # does not end a continuation already under way. Both halves verified with
    # `udevadm verify`: "# disabled \" followed by a bogus key reports the error
    # on line 2, so a comment's own trailing backslash swallows nothing, while
    # 'SUBSYSTEM=="power_supply" \' + "# c" + ', RUN+="..."' reports its style
    # warning on line 1, so the rule spans the comment. Testing the comment after
    # the join would hide a live rule; clearing the pending line here would hide
    # one just as well.
    if [[ $line =~ ^[[:space:]]*# ]]; then
      continue
    fi

    # A trailing backslash continues the rule on the next line.
    if [[ $line == *\\ ]]; then
      logical+=${line%\\}
      continue
    fi

    rest=$logical$line
    logical=""

    while [[ $rest == *'RUN+="'* ]]; do
      rest=${rest#*'RUN+="'}
      command=${rest%%'"'*}
      rest=${rest#*'"'}

      # The legacy rules put the binary first (wifi power save) or last, after a
      # systemd-run invocation (power profile), and some variants passed it an
      # argument. Compare whole words so no substring stands in for the path.
      read -ra words <<<"$command"
      for word in "${words[@]}"; do
        if [[ $word =~ $pattern ]]; then
          return 0
        fi
      done
    done
  done <"$file"

  return 1
}

finish_pending_reload() {
  # With no control socket there is no running udevd holding the deleted rule;
  # the next daemon start reads the directory from disk. If a daemon is running,
  # a failed reload must keep this migration pending so the in-memory root rule
  # cannot outlive the per-user completion marker.
  if [[ -e $udev_control ]] && ! as_root udevadm control --reload 2>/dev/null; then
    echo "Could not reload udev after removing a vulnerable legacy rule. Ask an administrator to run omarchy-migrate." >&2
    exit 1
  fi

  if ! as_root rm -f "$reload_needed_marker"; then
    echo "Could not finish the legacy udev-rule repair. Ask an administrator to run omarchy-migrate." >&2
    exit 1
  fi
}

# Deleting the file and reloading the daemon are one repair. A prior run may
# have removed the file and then failed before udevd accepted the new ruleset.
if [[ -e $reload_needed_marker ]]; then
  finish_pending_reload
fi

for legacy_rule in "99-power-profile.rules:omarchy-powerprofiles-set" "99-wifi-powersave.rules:omarchy-wifi-powersave"; do
  rule_file="$rules_dir/${legacy_rule%%:*}"

  if [[ -f $rule_file ]] && rule_runs_from_home "$rule_file" "${legacy_rule##*:}"; then
    if ! as_root install -Dm644 /dev/null "$reload_needed_marker"; then
      echo "Administrator privileges are required to remove the vulnerable legacy udev rule. Ask an administrator to run omarchy-migrate." >&2
      exit 1
    fi
    if ! as_root rm -f "$rule_file"; then
      echo "Administrator privileges are required to remove the vulnerable legacy udev rule. Ask an administrator to run omarchy-migrate." >&2
      exit 1
    fi

    finish_pending_reload
  fi
done