#!/usr/bin/env bash
set -euo pipefail

UID="$(id -u)"
USER_BUS="/run/user/$UID/bus"
HM_DIR="$HOME/.config/home-manager"
SKEL_DIR="/etc/skel/.config/home-manager"

# Ensure basic PATH for user units
export PATH="/run/current-system/sw/bin:${PATH:-}"

# Attach to session bus if possible
if [[ -z "${DBUS_SESSION_BUS_ADDRESS:-}" && -S "$USER_BUS" ]]; then
  export DBUS_SESSION_BUS_ADDRESS="unix:path=$USER_BUS"
fi

have() { command -v "$1" >/dev/null 2>&1; }

# ---- Session sanity check ---------------------------------------------------

if have loginctl && [[ -n "${XDG_SESSION_ID:-}" ]]; then
  # One loginctl call instead of three
  eval "$(
    loginctl show-session "$XDG_SESSION_ID" \
      -p Class -p State -p LockedHint \
      --value 2>/dev/null |
    awk '
      NR==1{print "SESSION_CLASS="$0}
      NR==2{print "SESSION_STATE="$0}
      NR==3{print "SESSION_LOCKED="$0}
    '
  )"

  [[ "${SESSION_CLASS:-}" == "user" ]]   || exit 0
  [[ "${SESSION_STATE:-}" == "active" ]] || exit 0
  [[ "${SESSION_LOCKED:-yes}" == "no" ]] || exit 0
fi

# ---- Notifications ----------------------------------------------------------

notifications_ready() {
  [[ "${XDG_SESSION_CLASS:-user}" == "user" ]] || return 1
  [[ -n "${DBUS_SESSION_BUS_ADDRESS:-}" ]]     || return 1
  have gdbus                                  || return 1

  # Wait for unlock if loginctl is present
  if have loginctl && [[ -n "${XDG_SESSION_ID:-}" ]]; then
    for _ in {1..7}; do
      [[ "$(loginctl show-session "$XDG_SESSION_ID" \
            -p LockedHint --value 2>/dev/null)" == "no" ]] && break
      sleep 2
    done
  fi

  # Wait for notification service
  for _ in {1..7}; do
    gdbus introspect --session \
      --dest org.freedesktop.Notifications \
      --object-path /org/freedesktop/Notifications \
      >/dev/null 2>&1 && return 0
    sleep 2
  done

  return 1
}

notify() {
  have notify-send || return 0
  notifications_ready || return 0
  notify-send \
    --app-name="Bootstrap" \
    --urgency=critical \
    --expire-time=0 \
    "$@" >/dev/null 2>&1 || true
}

notify "Reticulating Splines" "Bootstrapping. Please stay tuned."
trap 'notify "Bootstrap finished" "Your system is fully hydrated. It is recommended to logout and back in."' EXIT

# ---- Home Manager bootstrap -------------------------------------------------

mkdir -p "$HM_DIR"

for f in flake.nix home.nix; do
  src="$SKEL_DIR/$f"
  dst="$HM_DIR/$f"
  [[ -f "$src" && ! -e "$dst" ]] || continue
  install -m 600 "$src" "$dst"
done

home-manager switch --flake "$HM_DIR#admin"
touch "$HM_DIR/.hm_bootstrap_done"