#!/usr/bin/env sh

set -eu

APPLY=0
AGGRESSIVE=0

SAFE_PACKAGES="
arandr
autorandr
feh
i3
i3blocks
i3blocks-blocklets
i3lock-color
i3status
scrot
setxkbmap
volumeicon
xclip
xkbutils
xorg-fonts
xorg-minimal
xss-lock
"

AGGRESSIVE_PACKAGES="
dunst
rofi
blueman
network-manager-applet
xfce-polkit
xfce4-clipman-plugin
xfce4-screenshooter
"

SAFE_PATHS="
$HOME/.config/i3
$HOME/.config/i3blocks
$HOME/.config/autorandr
$HOME/.xinitrc
"

AGGRESSIVE_PATHS="
$HOME/.config/dunst
$HOME/.config/rofi
"

usage() {
  cat <<'EOF'
Usage: cleanup_i3_after_sway_migration.sh [--apply] [--aggressive]

One-shot cleanup for removing i3/X11-only packages and dotfiles after a host
has already migrated to SwayFX + Noctalia.

Options:
  --apply       perform the cleanup for real
  --aggressive  also remove extra desktop apps/configs that were mainly useful
                in the old i3 setup (dunst, rofi, blueman, etc.)
  -h, --help    show this help

Default mode is dry-run.
EOF
}

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

require_sway_noctalia() {
  if [ ! -f "$HOME/.config/sway/config" ]; then
    printf 'Error: Sway config not found at %s\n' "$HOME/.config/sway/config" >&2
    exit 1
  fi

  if [ ! -f "$HOME/.config/noctalia/settings.json" ]; then
    printf 'Error: Noctalia settings not found at %s\n' "$HOME/.config/noctalia/settings.json" >&2
    exit 1
  fi
}

append_lines() {
  src_lines=$1
  dst_var=$2

  for line in $src_lines; do
    line=$(printf '%s' "$line" | sed 's/^[[:space:]]*//;s/[[:space:]]*$//')
    [ -n "$line" ] || continue
    case "$dst_var" in
      PACKAGES)
        PACKAGES="$PACKAGES $line"
        ;;
      PATHS)
        PATHS="$PATHS $line"
        ;;
      *)
        printf 'Error: unsupported destination list: %s\n' "$dst_var" >&2
        exit 1
        ;;
    esac
  done
}

filter_installed_packages() {
  packages=$1
  installed=''

  for pkg in $packages; do
    pkg=$(printf '%s' "$pkg" | sed 's/^[[:space:]]*//;s/[[:space:]]*$//')
    [ -n "$pkg" ] || continue
    if xbps-query -s "$pkg" >/dev/null 2>&1; then
      installed="$installed $pkg"
    fi
  done

  printf '%s' "$installed"
}

filter_existing_paths() {
  paths=$1
  existing=''

  for path in $paths; do
    path=$(printf '%s' "$path" | sed 's/^[[:space:]]*//;s/[[:space:]]*$//')
    [ -n "$path" ] || continue
    if [ -e "$path" ] || [ -L "$path" ]; then
      existing="$existing $path"
    fi
  done

  printf '%s' "$existing"
}

print_section() {
  title=$1
  items=$2

  printf '%s\n' "$title"
  if [ -z "$items" ]; then
    printf '  (none)\n'
    return
  fi

  for item in $items; do
    item=$(printf '%s' "$item" | sed 's/^[[:space:]]*//;s/[[:space:]]*$//')
    [ -n "$item" ] || continue
    printf '  - %s\n' "$item"
  done
}

confirm_apply() {
  printf 'Proceed with i3 cleanup? [y/N] '
  IFS= read -r answer
  case "$answer" in
    y|Y|yes|YES)
      ;;
    *)
      printf 'Aborted.\n'
      exit 0
      ;;
  esac
}

run_remove_packages() {
  packages=$1
  [ -n "$packages" ] || return 0

  if [ "$(id -u)" -eq 0 ]; then
    xbps-remove -R $packages
  elif have_command sudo; then
    sudo xbps-remove -R $packages
  else
    printf 'Error: package removal requires root and sudo was not found.\n' >&2
    exit 1
  fi
}

run_remove_paths() {
  paths=$1
  [ -n "$paths" ] || return 0

  for path in $paths; do
    path=$(printf '%s' "$path" | sed 's/^[[:space:]]*//;s/[[:space:]]*$//')
    [ -n "$path" ] || continue
    rm -rf "$path"
  done
}

while [ $# -gt 0 ]; do
  case "$1" in
    --apply)
      APPLY=1
      ;;
    --aggressive)
      AGGRESSIVE=1
      ;;
    -h|--help)
      usage
      exit 0
      ;;
    *)
      printf 'Error: unknown argument: %s\n\n' "$1" >&2
      usage >&2
      exit 1
      ;;
  esac
  shift
done

require_sway_noctalia

PACKAGES=''
PATHS=''
append_lines "$SAFE_PACKAGES" PACKAGES
append_lines "$SAFE_PATHS" PATHS

if [ "$AGGRESSIVE" -eq 1 ]; then
  append_lines "$AGGRESSIVE_PACKAGES" PACKAGES
  append_lines "$AGGRESSIVE_PATHS" PATHS
fi

INSTALLED_PACKAGES=$(filter_installed_packages "$PACKAGES")
EXISTING_PATHS=$(filter_existing_paths "$PATHS")

printf 'Mode: %s\n' "$( [ "$APPLY" -eq 1 ] && printf 'apply' || printf 'dry-run' )"
printf 'Aggressive cleanup: %s\n\n' "$( [ "$AGGRESSIVE" -eq 1 ] && printf 'yes' || printf 'no' )"

print_section 'Packages to remove:' "$INSTALLED_PACKAGES"
printf '\n'
print_section 'Paths to remove:' "$EXISTING_PATHS"

if [ "$APPLY" -ne 1 ]; then
  printf '\nDry-run only. Re-run with --apply to perform the cleanup.\n'
  exit 0
fi

confirm_apply

run_remove_packages "$INSTALLED_PACKAGES"
run_remove_paths "$EXISTING_PATHS"

printf '\nCleanup complete.\n'