#!/bin/bash

is_installed() {
  command -v gnome-shell &>/dev/null
}

run_update() {
  echo "Updating GNOME extensions..."

  # Reinstall gext if missing or broken (e.g. its pipx venv went stale after a Python upgrade)
  if ! ~/.local/bin/gext --version &> /dev/null; then
    echo "gext missing or broken, reinstalling..."
    pipx uninstall gnome-extensions-cli 2>/dev/null || true
    pipx install --python "$(which python3)" gnome-extensions-cli --system-site-packages
  fi

  # Update every enabled user extension to the latest version for this GNOME Shell.
  # The filesystem backend writes directly to ~/.local/share/gnome-shell/extensions;
  # GNOME Shell picks up the new code at next login.
  if ~/.local/bin/gext --filesystem update --user --yes; then
    echo "GNOME extensions up to date. Log out and back in to load any updated extensions."
  else
    echo "gext update failed; GNOME extensions were not updated."
  fi

  reinstall_incompatible_extensions
}

# gext only updates when the store's version number is higher than the installed
# one, so a copy from elsewhere (e.g. a GitHub release with a different numbering)
# can be stuck on a build that doesn't support the current GNOME Shell. GNOME
# disables such extensions, so reinstall them fresh from extensions.gnome.org.
reinstall_incompatible_extensions() {
  local shell_major ext_root enabled dir uuid backup
  shell_major="$(gnome-shell --version | grep -oE '[0-9]+' | head -1)"
  ext_root="$HOME/.local/share/gnome-shell/extensions"
  enabled="$(gsettings get org.gnome.shell enabled-extensions)"

  for dir in "$ext_root"/*/; do
    [ -f "$dir/metadata.json" ] || continue
    uuid="$(basename "$dir")"
    [[ "$enabled" == *"'$uuid'"* ]] || continue

    if python3 -c 'import json, sys; m = json.load(open(sys.argv[1])); sys.exit(0 if any(str(v).split(".")[0] == sys.argv[2] for v in m.get("shell-version", [])) else 1)' \
        "$dir/metadata.json" "$shell_major"; then
      continue
    fi

    echo "$uuid doesn't support GNOME Shell $shell_major, reinstalling from extensions.gnome.org..."
    backup="$(mktemp -d)"
    mv "$dir" "$backup/$uuid"
    if ~/.local/bin/gext --filesystem install "$uuid" && [ -f "$ext_root/$uuid/metadata.json" ]; then
      rm -rf "$backup"
    else
      echo "Reinstall of $uuid failed; restoring the previous version."
      rm -rf "$ext_root/$uuid"
      mv "$backup/$uuid" "$ext_root/$uuid"
      rmdir "$backup"
    fi
  done
}