#!/usr/bin/env bash
set -o errexit
set -o nounset
set -o pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# shellcheck source=00-platform-guard.inc
source "$SCRIPT_DIR/00-platform-guard.inc"
SOURCE_FILE="$SCRIPT_DIR/../files/bashrc.d/ailab.sh"
PROFILE_DIR="/root/.bashrc.d"
PROFILE_FILE="$PROFILE_DIR/ailab.sh"
BASHRC="/root/.bashrc"
SOURCE_LINE='[[ -f /root/.bashrc.d/ailab.sh ]] && source /root/.bashrc.d/ailab.sh'

backup_file() {
  local path="$1"
  local backup

  backup="${path}.$(date '+%Y%m%d-%H%M%S').bak"
  install -m 0644 "$path" "$backup"
  printf 'INFO: backed up %s to %s\n' "$path" "$backup"
}

if ((EUID != 0)); then
  printf 'CRITICAL: shell profile setup must run as root\n' >&2
  exit 2
fi
require_supported_ubuntu
if [[ ! -r "$SOURCE_FILE" ]]; then
  printf 'CRITICAL: shell profile source is missing: %s\n' "$SOURCE_FILE" >&2
  exit 2
fi

install -d -m 0755 "$PROFILE_DIR"
if [[ ! -f "$PROFILE_FILE" ]] || ! cmp -s "$SOURCE_FILE" "$PROFILE_FILE"; then
  if [[ -f "$PROFILE_FILE" ]]; then
    backup_file "$PROFILE_FILE"
  fi
  install -m 0644 "$SOURCE_FILE" "$PROFILE_FILE"
  printf 'OK: installed %s\n' "$PROFILE_FILE"
else
  printf 'OK: shell profile is already current\n'
fi

if [[ ! -f "$BASHRC" ]]; then
  install -m 0644 /dev/null "$BASHRC"
fi

source_count="$(grep -Fxc "$SOURCE_LINE" "$BASHRC" || true)"
if [[ "$source_count" != "1" ]]; then
  tmp_bashrc="$(mktemp)"
  trap 'rm -f "$tmp_bashrc"' EXIT
  grep -Fvx "$SOURCE_LINE" "$BASHRC" >"$tmp_bashrc" || true
  printf '\n%s\n' "$SOURCE_LINE" >>"$tmp_bashrc"
  backup_file "$BASHRC"
  install -m 0644 "$tmp_bashrc" "$BASHRC"
  printf 'OK: configured %s to source the AI lab profile exactly once\n' "$BASHRC"
else
  printf 'OK: %s already sources the AI lab profile exactly once\n' "$BASHRC"
fi