const { ipcRenderer } = require('electron');
const Peer = require('peerjs').default || require('peerjs');

let input = null;
try { input = require('./input'); } catch {}

// ─── DOM ───
const myIdEl        = document.getElementById('my-id');
const remoteIdInput = document.getElementById('remote-id');
const remoteKeyInput = document.getElementById('remote-key');
const btnConnect    = document.getElementById('btn-connect');
const btnShare      = document.getElementById('btn-share');
const btnCopy       = document.getElementById('btn-copy');
const btnKill       = document.getElementById('btn-kill');
const btnRenew      = document.getElementById('btn-renew');
const myKeyEl       = document.getElementById('my-key');
const killOverlay   = document.getElementById('kill-overlay');
const killClose     = document.getElementById('kill-close');
const rcIndicator   = document.getElementById('rc-indicator');
const cbAot         = document.getElementById('cb-aot');
const cbCtrl        = document.getElementById('cb-ctrl');
const remoteVideo   = document.getElementById('remote-video');
const statusEl      = document.getElementById('status-text');
const statusDot     = document.getElementById('dot');
const placeholder   = document.getElementById('placeholder');
const toast         = document.getElementById('toast');
const trustBadge    = document.getElementById('trust-badge');
const savedPeersEl  = document.getElementById('saved-peers');

// ─── Persistente Zugangsdaten ───
function generateId() { return String(Math.floor(100000 + Math.random() * 900000)); }
function generateKey() {
  const c = 'ABCDEFGHJKLMNPQRSTUVWXYZ23456789';
  let k = '';
  for (let i = 0; i < 8; i++) k += c[Math.floor(Math.random() * c.length)];
  return k;
}

let MY_ID = localStorage.getItem('savedPeerId');
let SECRET_KEY = localStorage.getItem('savedSecretKey');
if (!MY_ID || !SECRET_KEY) {
  MY_ID = generateId();
  SECRET_KEY = generateKey();
  localStorage.setItem('savedPeerId', MY_ID);
  localStorage.setItem('savedSecretKey', SECRET_KEY);
}
myKeyEl.textContent = SECRET_KEY;

// ─── Gespeicherte Verbindungen ───
let savedConns = JSON.parse(localStorage.getItem('savedConnections') || '{}');

function saveSavedConns() {
  localStorage.setItem('savedConnections', JSON.stringify(savedConns));
  renderSavedPeers();
}

// ─── State ───
let localStream = null;
let sharing = false;
let dataConn = null;
let incomingConn = null;
let activeCall = null;
let incomingCall = null;
let remoteW = null;
let remoteH = null;
let windowFocused = true;
let killed = false;
let connected = false;
let authenticatedPeers = new Set();

window.addEventListener('focus', () => { windowFocused = true; });
window.addEventListener('blur', () => { windowFocused = false; });

// ─── Auto-fill letzte Verbindung ───
const lastPeerId = localStorage.getItem('lastConnectedPeer') || '';
if (lastPeerId) {
  remoteIdInput.value = lastPeerId;
  if (savedConns[lastPeerId]) {
    remoteKeyInput.value = savedConns[lastPeerId].key;
  }
}
updateTrustBadge();

function updateTrustBadge() {
  const tid = remoteIdInput.value.trim();
  if (savedConns[tid]) {
    trustBadge.classList.add('show');
    if (!remoteKeyInput.value.trim()) {
      remoteKeyInput.value = savedConns[tid].key;
    }
    remoteKeyInput.classList.add('trusted');
  } else {
    trustBadge.classList.remove('show');
    remoteKeyInput.classList.remove('trusted');
  }
}

remoteIdInput.addEventListener('input', () => {
  const tid = remoteIdInput.value.trim();
  if (savedConns[tid]) {
    remoteKeyInput.value = savedConns[tid].key;
  } else {
    remoteKeyInput.value = '';
  }
  updateTrustBadge();
});

// ─── Gespeicherte Peers im Placeholder anzeigen ───
function renderSavedPeers() {
  if (!savedPeersEl) return;
  const peers = Object.entries(savedConns);
  if (peers.length === 0) {
    savedPeersEl.classList.remove('show');
    return;
  }
  savedPeersEl.innerHTML = '<div class="saved-peers-title">Gespeicherte Verbindungen</div>';
  peers.sort((a, b) => (b[1].lastUsed || 0) - (a[1].lastUsed || 0));
  peers.forEach(([id, data]) => {
    const item = document.createElement('div');
    item.className = 'saved-peer-item';
    const timeStr = data.lastUsed ? new Date(data.lastUsed).toLocaleDateString('de-DE') : '';
    item.innerHTML =
      '<span class="saved-peer-id">' + id + '</span>' +
      '<span class="saved-peer-time">' + timeStr + '</span>' +
      '<button class="saved-peer-remove" title="Entfernen">&times;</button>';
    item.querySelector('.saved-peer-id').addEventListener('click', () => {
      remoteIdInput.value = id;
      remoteKeyInput.value = data.key;
      updateTrustBadge();
    });
    item.querySelector('.saved-peer-remove').addEventListener('click', (e) => {
      e.stopPropagation();
      delete savedConns[id];
      saveSavedConns();
      updateTrustBadge();
    });
    savedPeersEl.appendChild(item);
  });
  savedPeersEl.classList.add('show');
}
renderSavedPeers();

// ─── UI Helpers ───
function setStatus(msg, color) {
  statusEl.textContent = msg;
  if (color) statusEl.style.color = color;
}

function setOnline(on) {
  statusDot.classList.toggle('online', on);
}

function showToast(msg, isKill) {
  toast.textContent = msg;
  toast.className = 'toast show' + (isKill ? ' kill' : '');
  setTimeout(() => toast.classList.remove('show'), 2200);
}

function updateRcIndicator() {
  const active = connected && ((dataConn && dataConn.open) || (incomingConn && incomingConn.open));
  rcIndicator.classList.toggle('show', !!active && cbCtrl.checked && !killed);
}

// ═══════════════════════════════════════════
//  DISCONNECT: Verbindung trennen, Peer bleibt
// ═══════════════════════════════════════════
function disconnect() {
  if (activeCall) { try { activeCall.close(); } catch {} activeCall = null; }
  if (incomingCall) { try { incomingCall.close(); } catch {} incomingCall = null; }
  if (dataConn) { try { dataConn.close(); } catch {} dataConn = null; }
  if (incomingConn) { try { incomingConn.close(); } catch {} incomingConn = null; }

  remoteVideo.srcObject = null;
  connected = false;
  remoteW = null;
  remoteH = null;

  rcIndicator.classList.remove('show');
  placeholder.classList.remove('hidden');
  document.body.classList.add('no-stream');

  if (!killed) {
    setStatus('Bereit – warte auf Verbindung', '#2ea043');
  }
  showToast('Verbindung getrennt');
}

// ═══════════════════════════════════════════
//  KILL: Alles zerstören (Notaus)
// ═══════════════════════════════════════════
function killAll(showOverlay) {
  disconnect();

  if (localStream) {
    localStream.getTracks().forEach((t) => t.stop());
    localStream = null;
  }
  sharing = false;

  try { peer.disconnect(); } catch {}
  try { peer.destroy(); } catch {}

  killed = true;

  setOnline(false);
  btnShare.innerHTML = '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"><rect x="2" y="3" width="20" height="14" rx="2"/><line x1="8" y1="21" x2="16" y2="21"/><line x1="12" y1="17" x2="12" y2="21"/></svg> Screen teilen';
  btnShare.classList.remove('active');

  setStatus('OFFLINE – Alle Verbindungen gekappt', '#e5534b');

  if (showOverlay) {
    killOverlay.classList.add('show');
  }
}

function hardKill() {
  killAll(false);

  const h2 = killOverlay.querySelector('h2');
  const p = killOverlay.querySelector('p');
  if (h2) h2.textContent = 'SYSTEM OFFLINE';
  if (p) p.textContent = 'ALLE VERBINDUNGEN GEKAPPT';
  killOverlay.classList.add('show');

  setTimeout(() => ipcRenderer.send('cleanup-done'), 1000);
}

btnKill.addEventListener('click', () => disconnect());
killClose.addEventListener('click', () => killOverlay.classList.remove('show'));

ipcRenderer.on('kill-switch', () => disconnect());
ipcRenderer.on('hard-kill', () => hardKill());

function guardKilled() {
  if (killed) {
    setStatus('Session beendet – App neustarten', '#e5534b');
    return true;
  }
  return false;
}

// ─── PeerJS ───
const peer = new Peer(MY_ID, {
  config: {
    iceServers: [
      { urls: 'stun:stun.l.google.com:19302' },
      { urls: 'stun:stun1.l.google.com:19302' },
      { urls: 'stun:stun2.l.google.com:19302' },
      { urls: 'stun:stun3.l.google.com:19302' },
      { urls: 'stun:stun4.l.google.com:19302' },
    ],
  },
});

peer.on('open', (id) => {
  if (killed) return;
  myIdEl.textContent = id;
  setOnline(true);
  setStatus('Bereit – warte auf Verbindung', '#2ea043');
  ipcRenderer.invoke('save-credentials', MY_ID, SECRET_KEY);
  autoShare();
});

async function autoShare() {
  if (sharing || killed) return;
  try {
    const sources = await ipcRenderer.invoke('get-sources');
    if (!sources.length) return;
    localStream = await navigator.mediaDevices.getUserMedia({
      audio: false,
      video: { mandatory: {
        chromeMediaSource: 'desktop',
        chromeMediaSourceId: sources[0].id,
        maxWidth: 1920, maxHeight: 1080, maxFrameRate: 30,
      }},
    });
    sharing = true;
    btnShare.innerHTML = '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"><line x1="18" y1="6" x2="6" y2="18"/><line x1="6" y1="6" x2="18" y2="18"/></svg> Stop';
    btnShare.classList.add('active');
    setStatus('Bereit – warte auf Verbindung', '#2ea043');
  } catch {}
}

peer.on('error', (err) => {
  if (killed) return;
  if (err.type === 'unavailable-id') {
    setStatus('ID belegt – neuer Versuch...', '#e5534b');
    setTimeout(() => { if (!killed) location.reload(); }, 800);
    return;
  }
  setOnline(false);
  setStatus('Fehler: ' + err.type, '#e5534b');
});

peer.on('disconnected', () => {
  if (killed) return;
  setOnline(false);
  setStatus('Server-Verbindung verloren – Reconnect...', '#e5534b');
  setTimeout(() => {
    if (!killed && !peer.destroyed) {
      try { peer.reconnect(); } catch {}
    }
  }, 3000);
});

// ─── ID + Key kopieren ───
btnCopy.addEventListener('click', () => {
  const id = myIdEl.textContent;
  if (id && id !== '------') {
    navigator.clipboard.writeText(id + ' / ' + SECRET_KEY);
    btnCopy.classList.add('copied');
    showToast('ID + Key kopiert!');
    setTimeout(() => btnCopy.classList.remove('copied'), 2000);
  }
});

cbAot.addEventListener('change', () => ipcRenderer.send('set-always-on-top', cbAot.checked));
cbCtrl.addEventListener('change', () => updateRcIndicator());

btnRenew.addEventListener('click', () => {
  if (guardKilled()) return;
  MY_ID = generateId();
  SECRET_KEY = generateKey();
  localStorage.setItem('savedPeerId', MY_ID);
  localStorage.setItem('savedSecretKey', SECRET_KEY);
  showToast('Neue Zugangsdaten generiert – Neustart...');
  ipcRenderer.invoke('save-credentials', MY_ID, SECRET_KEY).then(() => {
    setTimeout(() => location.reload(), 1200);
  });
});

// ═══════════════════════════════════════════
//  EINGEHENDE VERBINDUNG: Auth prüfen
// ═══════════════════════════════════════════
peer.on('connection', (conn) => {
  if (killed) { conn.close(); return; }

  conn.on('open', () => {
    if (killed) { conn.close(); return; }
  });

  conn.on('data', (d) => {
    if (d.t === 'auth') {
      if (d.key === SECRET_KEY) {
        authenticatedPeers.add(conn.peer);
        conn.send({ t: 'auth-ok' });
        showToast('Verbindung akzeptiert: ' + conn.peer);

        incomingConn = conn;
        connected = true;

        if (input) {
          const s = input.getScreenSize();
          conn.send({ t: 'scr', w: s.width, h: s.height });
        }
        updateRcIndicator();
        setStatus('Verbunden mit ' + conn.peer, '#00b4d8');
      } else {
        conn.send({ t: 'auth-fail' });
        showToast('Zugang verweigert: falscher Key', true);
        setTimeout(() => conn.close(), 500);
      }
      return;
    }
    handleRemoteData(d);
  });

  conn.on('close', () => {
    if (incomingConn === conn) {
      incomingConn = null;
      connected = false;
      updateRcIndicator();
      placeholder.classList.remove('hidden');
      document.body.classList.add('no-stream');
      remoteVideo.srcObject = null;
      if (!killed) {
        setStatus('Bereit – warte auf Verbindung', '#2ea043');
        showToast('Gegenstelle hat getrennt');
      }
    }
  });
});

// ─── Eingehender Anruf: nur authentifizierte Peers ───
peer.on('call', (call) => {
  if (killed) return;

  if (!authenticatedPeers.has(call.peer)) {
    showToast('Anruf abgelehnt: nicht authentifiziert', true);
    return;
  }

  call.answer(localStream || undefined);
  incomingCall = call;

  call.on('stream', (stream) => {
    if (killed) return;
    remoteVideo.srcObject = stream;
    placeholder.classList.add('hidden');
    document.body.classList.remove('no-stream');
    setStatus('Verbunden mit ' + call.peer, '#00b4d8');
  });

  call.on('close', () => {
    if (incomingCall === call) { incomingCall = null; }
  });
});

// ─── Remote Data Handler ───
function handleRemoteData(d) {
  if (killed) return;
  if (d.t === 'scr') {
    remoteW = d.w; remoteH = d.h;
    return;
  }
  if (!input) return;
  if (!cbCtrl.checked) return;
  try {
    switch (d.t) {
      case 'mm': input.moveMouse(d.x|0, d.y|0); break;
      case 'md': input.moveMouse(d.x|0, d.y|0); input.mouseToggle('down', d.b||'left'); break;
      case 'mu': input.mouseToggle('up', d.b||'left'); break;
      case 'mc': input.moveMouse(d.x|0, d.y|0); input.mouseClick(d.b||'left'); break;
      case 'sc': input.scrollMouse(d.dx||0, d.dy||0); break;
      case 'kd': input.keyToggle(d.k, 'down'); break;
      case 'ku': input.keyToggle(d.k, 'up'); break;
    }
  } catch {}
}

// ─── Screen Share Toggle ───
btnShare.addEventListener('click', async () => {
  if (guardKilled()) return;
  if (sharing) {
    if (localStream) localStream.getTracks().forEach((t) => t.stop());
    localStream = null;
    sharing = false;
    btnShare.innerHTML = '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"><rect x="2" y="3" width="20" height="14" rx="2"/><line x1="8" y1="21" x2="16" y2="21"/><line x1="12" y1="17" x2="12" y2="21"/></svg> Screen teilen';
    btnShare.classList.remove('active');
    setStatus('Stream gestoppt', '#8b949e');
    return;
  }
  try {
    const sources = await ipcRenderer.invoke('get-sources');
    if (!sources.length) { setStatus('Keine Quelle!', '#e5534b'); return; }
    localStream = await navigator.mediaDevices.getUserMedia({
      audio: false,
      video: { mandatory: {
        chromeMediaSource: 'desktop',
        chromeMediaSourceId: sources[0].id,
        maxWidth: 1920, maxHeight: 1080, maxFrameRate: 30,
      }},
    });
    sharing = true;
    btnShare.innerHTML = '<svg width="14" height="14" viewBox="0 0 24 24" fill="none" stroke="currentColor" stroke-width="2.5" stroke-linecap="round" stroke-linejoin="round"><line x1="18" y1="6" x2="6" y2="18"/><line x1="6" y1="6" x2="18" y2="18"/></svg> Stop';
    btnShare.classList.add('active');
    setStatus('Capture aktiv', '#2ea043');
  } catch (e) {
    setStatus('Fehler: ' + e.message, '#e5534b');
  }
});

// ═══════════════════════════════════════════
//  VERBINDEN: Auth-Handshake + Screen-Call
// ═══════════════════════════════════════════
btnConnect.addEventListener('click', async () => {
  if (guardKilled()) return;
  const tid = remoteIdInput.value.trim();
  let tkey = remoteKeyInput.value.trim();

  if (!tid) { setStatus('Remote-ID eingeben!', '#e5534b'); return; }

  if (!tkey && savedConns[tid]) {
    tkey = savedConns[tid].key;
    remoteKeyInput.value = tkey;
  }

  if (!tkey) {
    setStatus('Remote-Key eingeben!', '#e5534b');
    remoteKeyInput.focus();
    return;
  }

  if (!sharing || !localStream) await autoShare();
  if (!localStream) { setStatus('Screen-Capture fehlgeschlagen!', '#e5534b'); return; }

  setStatus('Verbinde...', '#e5534b');
  btnConnect.disabled = true;

  dataConn = peer.connect(tid, { reliable: true });

  const authTimeout = setTimeout(() => {
    if (!connected) {
      setStatus('Zeitüberschreitung – Gegenstelle nicht erreichbar', '#e5534b');
      btnConnect.disabled = false;
      if (dataConn) { try { dataConn.close(); } catch {} dataConn = null; }
    }
  }, 15000);

  dataConn.on('open', () => {
    if (killed) return;
    setStatus('Authentifiziere...', '#e5534b');
    dataConn.send({ t: 'auth', key: tkey });
  });

  dataConn.on('data', (d) => {
    if (d.t === 'auth-ok') {
      clearTimeout(authTimeout);
      connected = true;
      btnConnect.disabled = false;

      savedConns[tid] = { key: tkey, lastUsed: Date.now() };
      saveSavedConns();
      localStorage.setItem('lastConnectedPeer', tid);
      updateTrustBadge();

      activeCall = peer.call(tid, localStream);
      activeCall.on('stream', (s) => {
        if (killed) return;
        remoteVideo.srcObject = s;
        placeholder.classList.add('hidden');
        document.body.classList.remove('no-stream');
      });

      if (input) {
        const s = input.getScreenSize();
        dataConn.send({ t: 'scr', w: s.width, h: s.height });
      }

      setStatus('Verbunden: ' + tid, '#00b4d8');
      showToast('Verbunden mit ' + tid);
      updateRcIndicator();
      return;
    }

    if (d.t === 'auth-fail') {
      clearTimeout(authTimeout);
      btnConnect.disabled = false;
      setStatus('Falscher Key! Zugang verweigert.', '#e5534b');
      showToast('Falscher Key!', true);

      if (savedConns[tid]) {
        delete savedConns[tid];
        saveSavedConns();
        updateTrustBadge();
        remoteKeyInput.value = '';
      }

      if (dataConn) { try { dataConn.close(); } catch {} dataConn = null; }
      return;
    }

    handleRemoteData(d);
  });

  dataConn.on('close', () => {
    clearTimeout(authTimeout);
    if (connected) {
      connected = false;
      dataConn = null;
      updateRcIndicator();
      showToast('Verbindung getrennt');
      if (!killed) setStatus('Bereit – warte auf Verbindung', '#2ea043');
      placeholder.classList.remove('hidden');
      document.body.classList.add('no-stream');
      remoteVideo.srcObject = null;
    } else {
      btnConnect.disabled = false;
      dataConn = null;
    }
  });

  dataConn.on('error', (err) => {
    clearTimeout(authTimeout);
    btnConnect.disabled = false;
    setStatus('Verbindungsfehler: ' + (err.type || err.message || err), '#e5534b');
  });
});

// ─── Koordinaten skalieren ───
function scale(e) {
  const r = remoteVideo.getBoundingClientRect();
  return {
    x: ((e.clientX - r.left) / r.width) * (remoteW || remoteVideo.videoWidth || 1920),
    y: ((e.clientY - r.top) / r.height) * (remoteH || remoteVideo.videoHeight || 1080),
  };
}

function sendCtrl(obj) {
  if (killed || !connected) return;
  if (!cbCtrl.checked) return;
  const conn = dataConn || incomingConn;
  if (!conn || !conn.open) return;
  conn.send(obj);
}

// ─── Maus-Events ───
remoteVideo.addEventListener('mousemove', (e) => {
  const c = scale(e); sendCtrl({ t:'mm', x:c.x, y:c.y });
});
remoteVideo.addEventListener('mousedown', (e) => {
  e.preventDefault();
  const c = scale(e);
  sendCtrl({ t:'md', x:c.x, y:c.y, b:['left','middle','right'][e.button]||'left' });
});
remoteVideo.addEventListener('mouseup', (e) => {
  e.preventDefault();
  sendCtrl({ t:'mu', b:['left','middle','right'][e.button]||'left' });
});
remoteVideo.addEventListener('wheel', (e) => {
  if (!cbCtrl.checked || killed || !connected) return;
  e.preventDefault();
  sendCtrl({ t:'sc', dx:Math.sign(e.deltaX)*3, dy:Math.sign(e.deltaY)*3 });
}, { passive: false });
remoteVideo.addEventListener('contextmenu', (e) => e.preventDefault());

// ─── Tastatur ───
document.addEventListener('keydown', (e) => {
  if (e.target.tagName === 'INPUT') return;
  if (e.key === 'Escape') { disconnect(); return; }
  if (killed || !cbCtrl.checked || !connected) return;
  e.preventDefault();
  sendCtrl({ t:'kd', k:mapKey(e.key) });
});
document.addEventListener('keyup', (e) => {
  if (e.target.tagName === 'INPUT') return;
  if (e.key === 'Escape') return;
  if (killed || !cbCtrl.checked || !connected) return;
  e.preventDefault();
  sendCtrl({ t:'ku', k:mapKey(e.key) });
});

function mapKey(k) {
  const m = {
    Enter:'enter',Backspace:'backspace',Delete:'delete',Tab:'tab',
    ' ':'space',
    ArrowUp:'up',ArrowDown:'down',ArrowLeft:'left',ArrowRight:'right',
    Home:'home',End:'end',PageUp:'pageup',PageDown:'pagedown',
    Control:'control',Shift:'shift',Alt:'alt',Insert:'insert',
    F1:'f1',F2:'f2',F3:'f3',F4:'f4',F5:'f5',F6:'f6',
    F7:'f7',F8:'f8',F9:'f9',F10:'f10',F11:'f11',F12:'f12',
  };
  return m[k] || k.toLowerCase();
}

// ─── Auto-Dim ───
let dimTimer;
document.addEventListener('mousemove', () => {
  const bar = document.getElementById('bar');
  bar.classList.remove('dim');
  clearTimeout(dimTimer);
  if (!document.body.classList.contains('no-stream')) {
    dimTimer = setTimeout(() => bar.classList.add('dim'), 3000);
  }
});

// ─── Fenster-Close Guard ───
window.addEventListener('beforeunload', () => {
  if (!killed) killAll(false);
});