// Eigenes Menüfenster für das Tray-Symbol.
// Das native Electron-Menü zeichnet unter Windows keine Hover-Markierung; dieses kleine Fenster
// (renderer/tray-menu.html) übernimmt Aussehen und Markierung selbst.

const { BrowserWindow, screen, nativeTheme, ipcMain } = require('electron');

const WIDTH = 286;          // Fensterbreite inkl. 8 px Rand für den Schatten
const DEFAULT_HEIGHT = 320;
const MARGIN = 8;

function clamp(value, min, max) {
  return Math.max(min, Math.min(value, Math.max(min, max)));
}

// Position des Menüs: am Mauszeiger, innerhalb des sichtbaren Bereichs. Liegt der Zeiger in der
// Taskleiste (unter/über dem Arbeitsbereich), sitzt das Menü direkt daneben.
function computePosition(point, workArea, width, height) {
  const x = clamp(point.x - Math.round(width / 2), workArea.x + MARGIN, workArea.x + workArea.width - width - MARGIN);
  let y;
  if (point.y >= workArea.y + workArea.height) y = workArea.y + workArea.height - height - MARGIN;
  else if (point.y <= workArea.y) y = workArea.y + MARGIN;
  else y = clamp(point.y - Math.round(height / 2), workArea.y + MARGIN, workArea.y + workArea.height - height - MARGIN);
  return { x, y };
}

function createTrayPopup({ htmlPath, preloadPath, getModel, onAction }) {
  let win = null;
  let height = DEFAULT_HEIGHT;
  let shownAt = 0;
  let handlersRegistered = false;

  const own = (event) => win && !win.isDestroyed() && event.sender === win.webContents;

  function registerHandlers() {
    if (handlersRegistered) return;
    handlersRegistered = true;
    ipcMain.on('tray-menu:action', (event, id) => {
      if (!own(event)) return;
      hide();
      try { onAction(String(id)); } catch (e) { console.warn('[Tray] Aktion fehlgeschlagen:', e.message); }
    });
    ipcMain.on('tray-menu:close', (event) => { if (own(event)) hide(); });
    ipcMain.on('tray-menu:resize', (event, contentHeight) => {
      if (!own(event)) return;
      const h = Math.round(Number(contentHeight));
      if (!(h > 40 && h < 900)) return;
      height = h;
      if (win.isVisible()) {
        const { x, y } = computePosition(screen.getCursorScreenPoint(), screen.getDisplayNearestPoint(screen.getCursorScreenPoint()).workArea, WIDTH, height);
        win.setBounds({ x, y, width: WIDTH, height });
      } else {
        win.setContentSize(WIDTH, height);
      }
    });
  }

  function ensureWindow() {
    if (win && !win.isDestroyed()) return win;
    registerHandlers();
    win = new BrowserWindow({
      width: WIDTH,
      height,
      show: false,
      frame: false,
      transparent: true,
      resizable: false,
      movable: false,
      minimizable: false,
      maximizable: false,
      fullscreenable: false,
      skipTaskbar: true,
      alwaysOnTop: true,
      focusable: true,
      hasShadow: false,
      webPreferences: {
        preload: preloadPath,
        contextIsolation: true,
        nodeIntegration: false,
        sandbox: true,
        spellcheck: false
      }
    });
    win.setAlwaysOnTop(true, 'pop-up-menu');
    win.on('blur', () => { if (Date.now() - shownAt > 250) hide(); });
    win.on('closed', () => { win = null; });
    win.loadFile(htmlPath);
    return win;
  }

  function push() {
    if (!win || win.isDestroyed()) return;
    win.webContents.send('tray-menu-state', { items: getModel(), dark: nativeTheme.shouldUseDarkColors });
  }

  function show() {
    const w = ensureWindow();
    const send = () => {
      push();
      const point = screen.getCursorScreenPoint();
      const { x, y } = computePosition(point, screen.getDisplayNearestPoint(point).workArea, WIDTH, height);
      w.setBounds({ x, y, width: WIDTH, height });
      shownAt = Date.now();
      w.show();
      w.focus();
    };
    if (w.webContents.isLoading()) w.webContents.once('did-finish-load', send);
    else send();
  }

  function hide() {
    if (win && !win.isDestroyed() && win.isVisible()) win.hide();
  }

  function refresh() {
    if (win && !win.isDestroyed() && win.isVisible()) push();
  }

  // Lädt das versteckte Fenster im Voraus. Der erste Start des Renderers dauert mehrere Sekunden;
  // ohne Vorladen würde der erste Rechtsklick auf das Tray-Symbol entsprechend hängen.
  function warmUp() {
    ensureWindow();
  }

  function destroy() {
    if (win && !win.isDestroyed()) win.destroy();
    win = null;
  }

  return {
    show,
    warmUp,
    hide,
    refresh,
    destroy,
    isVisible: () => !!win && !win.isDestroyed() && win.isVisible(),
    getWindow: () => (win && !win.isDestroyed() ? win : null)
  };
}

module.exports = { createTrayPopup, computePosition };