import Gio from 'gi://Gio';
import Meta from 'gi://Meta';
import Shell from 'gi://Shell';

const BUS = 'io.qvac.Jarvis.Shell';
const PATH = '/io/qvac/Jarvis/Shell';
const XML = `<node><interface name="io.qvac.Jarvis.Shell"><method name="ListWindows"><arg type="s" direction="out"/></method><method name="FocusedWindow"><arg type="s" direction="out"/></method><method name="FocusWindow"><arg type="t" direction="in"/></method><method name="Screenshot"><arg type="s" direction="in"/><arg type="s" direction="out"/></method></interface></node>`;
const describe = (window) => ({ id: Number(window.get_id?.() || 0), title: window.get_title?.() || '', wm_class: window.get_wm_class?.() || '', pid: Number(window.get_pid?.() || 0), rect: (() => { const r = window.get_frame_rect?.(); return r ? [r.x, r.y, r.width, r.height] : null; })(), buffer_rect: (() => { const r = window.get_buffer_rect?.(); return r ? [r.x, r.y, r.width, r.height] : null; })(), focused: window === global.display.get_focus_window?.() });

export function installShellService() {
  const implementation = {
    ListWindows() { const windows = global.display.get_tab_list(Meta.TabList.NORMAL_ALL, null).map(describe); return JSON.stringify(windows); },
    FocusedWindow() { const window = global.display.get_focus_window?.(); return JSON.stringify(window ? describe(window) : null); },
    FocusWindow(id) { const window = global.display.get_tab_list(Meta.TabList.NORMAL_ALL, null).find((candidate) => Number(candidate.get_id?.()) === Number(id)); if (!window) throw new Error('window not found'); window.activate(global.get_current_time()); },
    async Screenshot(filename) {
      const file = Gio.File.new_for_path(filename);
      const stream = file.replace(null, false, Gio.FileCreateFlags.REPLACE_DESTINATION, null);
      try {
        const screenshot = new Shell.Screenshot();
        await screenshot.screenshot(false, stream);
      } finally {
        stream.close(null);
      }
      return filename;
    },
  };
  const ownerId = Gio.bus_own_name(Gio.BusType.SESSION, BUS, Gio.BusNameOwnerFlags.NONE, (connection) => { const exported = Gio.DBusExportedObject.wrapJSObject(XML, implementation); exported.export(connection, PATH); implementation._exported = exported; }, null, () => {});
  return () => { implementation._exported?.unexport(); Gio.bus_unown_name(ownerId); };
}