#!/usr/bin/env bash
# kernel-kingdom installer.
#   curl -fsSL https://raw.githubusercontent.com/rsmedrano-cloud/kernel-kingdom/main/install.sh | bash
# Installs into ~/.local/share/kernel-kingdom/venv (uses the system's GTK/PyGObject),
# links ~/.local/bin/kernel-kingdom and enables the systemd --user services.
# Options (env vars): KERNEL_KINGDOM_REPO=<github url>  KERNEL_KINGDOM_NO_SERVICE=1
#                     KERNEL_KINGDOM_YES=1 (install missing system packages without asking)
set -euo pipefail

REPO="${KERNEL_KINGDOM_REPO:-https://github.com/rsmedrano-cloud/kernel-kingdom}"
PREFIX="${XDG_DATA_HOME:-$HOME/.local/share}/kernel-kingdom"
BIN="$HOME/.local/bin"

say() { printf '\033[1;33m==>\033[0m %s\n' "$*"; }
die() { printf '\033[1;31mxx\033[0m %s\n' "$*" >&2; exit 1; }

# -- system packages ----------------------------------------------------------
# GTK 4 and PyGObject come from the distro (they can't be pip-installed sanely). psutil and
# setuptools too when the distro has them: then nothing is fetched from PyPI (some networks
# or old machines can't reach it). gtk4-layer-shell is optional: without it there is no
# wallpaper mode, but the window works (also on X11).
# If something is missing we offer to install it; KERNEL_KINGDOM_YES=1 says yes.
check_core() {
  command -v python3 >/dev/null || return 1
  python3 - 2>/dev/null <<'PY'
import sys
assert sys.version_info >= (3, 11)
import venv, ensurepip, gi, cairo
gi.require_version("Gtk", "4.0")
PY
}
check_shell() { python3 -c 'import gi; gi.require_version("Gtk4LayerShell", "1.0")' 2>/dev/null; }
offline_build() {   # psutil + setuptools of the system: no PyPI needed
  python3 - 2>/dev/null <<'PY'
import importlib.util, psutil, setuptools
v = int(setuptools.__version__.split(".")[0])
assert v >= 61 and (v >= 71 or importlib.util.find_spec("wheel"))   # old setuptools builds wheels with `wheel`
PY
}

ask() {   # ask "question" -> 0 if yes. Works under curl | bash (reads the terminal).
  [ -n "${KERNEL_KINGDOM_YES:-}" ] && return 0
  [ -r /dev/tty ] || return 1
  local reply
  printf '\033[1;33m==>\033[0m %s [Y/n] ' "$1" > /dev/tty
  read -r reply < /dev/tty || return 1
  case "$reply" in [nN]*) return 1;; *) return 0;; esac
}

SUDO=""
[ "$(id -u)" -ne 0 ] && SUDO="sudo"
PKG_SHELL=""
if [ -e /run/ostree-booted ]; then
  PKG_CMD="rpm-ostree install --idempotent python3-gobject gtk4 gtk4-layer-shell"; SUDO=""; NEEDS_REBOOT=1
elif command -v dnf >/dev/null; then
  PKG_CMD="dnf install -y python3 python3-gobject gtk4 python3-psutil python3-setuptools python3-wheel"
  PKG_SHELL="dnf install -y gtk4-layer-shell"
elif command -v apt-get >/dev/null; then
  APT=1
  PKG_CMD="apt-get install -y python3 python3-venv python3-gi python3-gi-cairo gir1.2-gtk-4.0 python3-psutil python3-setuptools python3-wheel"
  PKG_SHELL="apt-get install -y libgtk4-layer-shell0 gir1.2-gtk4layershell-1.0"
elif command -v pacman >/dev/null; then
  PKG_CMD="pacman -S --needed --noconfirm python python-gobject python-cairo gtk4 python-psutil python-setuptools python-wheel"
  PKG_SHELL="pacman -S --needed --noconfirm gtk4-layer-shell"
else
  PKG_CMD=""
fi

if ! check_core || ! check_shell || { [ -z "${NEEDS_REBOOT:-}" ] && ! offline_build; }; then
  say "Kernel Kingdom needs Python 3.11+, GTK 4 and PyGObject from your distro (gtk4-layer-shell for the wallpaper mode)."
  [ -n "$PKG_CMD" ] || check_core || die "Install them with your package manager, then run this installer again."
  if [ -n "$PKG_CMD" ]; then
    echo "    ${SUDO:+$SUDO }$PKG_CMD"
    [ -n "$PKG_SHELL" ] && echo "    ${SUDO:+$SUDO }$PKG_SHELL"
    if ask "Install them now?"; then
      if [ -n "${APT:-}" ]; then $SUDO apt-get update -qq || true; fi
      $SUDO $PKG_CMD || check_core || die "The package install failed; fix it and run this installer again."
      if [ -n "$PKG_SHELL" ]; then
        $SUDO $PKG_SHELL || say "gtk4-layer-shell isn't available here: no wallpaper mode, the window works."
      fi
      if [ -n "${NEEDS_REBOOT:-}" ]; then
        say "Packages layered. Reboot, then run this installer again (Atomic desktops apply packages on boot)."
        exit 0
      fi
    elif ! check_core; then
      die "Run the command above, then this installer again."
    fi
  fi
  check_core || die "Still missing a dependency after installing. Please open an issue saying which distro you use."
fi
check_shell || say "No gtk4-layer-shell: the wallpaper mode won't be available, the window (kernel-kingdom window) will."

say "Creating virtualenv in $PREFIX"
python3 -m venv --system-site-packages "$PREFIX/venv"
SRC="$REPO"
# the latest published release, as a tarball (no git needed); main only if there is none yet
if [ -f pyproject.toml ] && grep -q 'name = "kernel-kingdom"' pyproject.toml; then
  SRC="."
else
  TAG=$(curl -fsSL -H "Accept: application/vnd.github+json" \
          "https://api.github.com/repos/${REPO#https://github.com/}/releases/latest" 2>/dev/null \
        | python3 -c 'import json, sys; print(json.load(sys.stdin).get("tag_name", ""))' 2>/dev/null || true)
  if [ -n "$TAG" ]; then SRC="$REPO/archive/refs/tags/$TAG.tar.gz"; else SRC="$REPO/archive/refs/heads/main.tar.gz"; fi
fi
say "Installing kernel-kingdom from $SRC"
if offline_build; then   # with the distro's psutil/setuptools nothing comes from PyPI
  "$PREFIX/venv/bin/pip" install --quiet --upgrade --no-build-isolation --no-deps "$SRC"
else
  "$PREFIX/venv/bin/pip" install --quiet --upgrade "$SRC"
fi

mkdir -p "$BIN"
ln -sf "$PREFIX/venv/bin/kernel-kingdom" "$BIN/kernel-kingdom"
case ":$PATH:" in *":$BIN:"*) ;; *) say "Add $BIN to your PATH";; esac

"$PREFIX/venv/bin/kernel-kingdom" doctor || true
if [ -z "${KERNEL_KINGDOM_NO_SERVICE:-}" ] && [ -n "${WAYLAND_DISPLAY:-}" ] && check_shell; then
  say "Enabling autostart (systemd --user) and the app launcher"
  "$PREFIX/venv/bin/kernel-kingdom" install || say "Could not enable the services; run 'kernel-kingdom' manually."
elif [ -z "${KERNEL_KINGDOM_NO_SERVICE:-}" ] && [ -n "${WAYLAND_DISPLAY:-}${DISPLAY:-}" ]; then
  say "Adding the app launcher (window mode)"
  "$PREFIX/venv/bin/kernel-kingdom" install --no-wallpaper || say "Run 'kernel-kingdom window' to play."
fi
say "Done. Commands: kernel-kingdom window | kernel-kingdom (wallpaper) | kernel-kingdom update | kernel-kingdom uninstall"