/**
 * CallKit (iOS) / ConnectionService (Android) Wrapper.
 *
 * Zentralisiert react-native-callkeep so dass stores/call.ts platform-agnostic
 * bleibt. Drei Verantwortungen:
 *   1. setup() einmal beim App-Start (Permission-Prompt auf Android)
 *   2. displayIncomingCall() wenn Push/Realtime ein Ring signalisiert
 *   3. startCall() wenn der User selbst einen Anruf initiiert
 *
 * Privacy für DiGA (sensible Userbasis, Art. 9 DSGVO):
 *   - includesCallsInRecents: false  → KEIN iCloud-Sync der Anrufliste
 *   - handle = userId (Email-Type)   → keine Telefonnummern-Style-Anzeige
 *   - appName "ReBreak-Audio"        → erscheint im Lockscreen-Banner
 */
import { Platform, PermissionsAndroid } from 'react-native';
import RNCallKeep, { CONSTANTS as CK_CONSTANTS } from 'react-native-callkeep';

let didSetup = false;

export async function setupCallKeep(): Promise<void> {
  if (didSetup) return;
  try {
    await RNCallKeep.setup({
      ios: {
        appName: 'ReBreak-Audio',
        // KEIN imageName → Default-Avatar von CallKit; wir setzen den echten
        // Caller-Namen via displayIncomingCall(localizedCallerName)
        supportsVideo: false,
        maximumCallGroups: '1',
        maximumCallsPerCallGroup: '1',
        // Privacy: KEINE Anrufliste in iOS-Recents (= kein iCloud-Sync, kein
        // Leak an Apple). Für DiGA mit Suchterkrankungs-Zielgruppe Pflicht.
        includesCallsInRecents: false,
      },
      android: {
        alertTitle: 'Anrufe in ReBreak zulassen',
        alertDescription:
          'ReBreak braucht Telefon-Konto-Berechtigung, um eingehende Sprach-Anrufe wie in Telefon-Apps anzuzeigen.',
        cancelButton: 'Nicht jetzt',
        okButton: 'Erlauben',
        // Foreground-Service für Android 11+ Mic-Background-Access
        foregroundService: {
          channelId: 'org.rebreak.app.calls',
          channelName: 'ReBreak-Anrufe',
          notificationTitle: 'ReBreak: Anruf aktiv',
        },
      },
    });
    if (Platform.OS === 'android') {
      RNCallKeep.setAvailable(true);
      // Android 14+: Full-Screen-Intent für Lockscreen-Call-UI braucht extra Permission
      try {
        await PermissionsAndroid.request(
          // @ts-ignore — RN-Types haben USE_FULL_SCREEN_INTENT evtl. noch nicht
          'android.permission.USE_FULL_SCREEN_INTENT' as any,
        );
      } catch {}
    }
    didSetup = true;
  } catch (e: any) {
    console.warn('[callkeep] setup failed', e?.message ?? e);
  }
}

/**
 * UUID-Generator — CallKit braucht lowercase UUID (Apple-Quirk).
 * Wir mappen 1:1 callId ↔ callUUID (deterministic) damit beide Apps dieselbe ID nutzen.
 */
export function callIdToUuid(callId: string): string {
  // CallId hat Format: "<timestamp>-<random8>", z.B. "1717491600000-abc12345"
  // Wir bauen daraus eine deterministische UUID v4-Form via simple Hex-Padding.
  const clean = callId.replace(/[^a-z0-9]/gi, '').toLowerCase().padEnd(32, '0').slice(0, 32);
  return `${clean.slice(0, 8)}-${clean.slice(8, 12)}-4${clean.slice(13, 16)}-8${clean.slice(17, 20)}-${clean.slice(20, 32)}`;
}

export function displayIncomingCall(callId: string, callerName: string): void {
  try {
    const uuid = callIdToUuid(callId);
    RNCallKeep.displayIncomingCall(
      uuid,
      callerName, // handle — wird im iOS-Lockscreen als Untertitel angezeigt
      callerName, // localizedCallerName — als Titel
      'generic',  // handleType: kein Phone-Number-Format
      false,      // hasVideo
    );
  } catch (e: any) {
    console.warn('[callkeep] displayIncomingCall failed', e?.message ?? e);
  }
}

export function startOutgoingCall(callId: string, calleeName: string): void {
  try {
    const uuid = callIdToUuid(callId);
    RNCallKeep.startCall(uuid, calleeName, calleeName, 'generic', false);
  } catch (e: any) {
    console.warn('[callkeep] startCall failed', e?.message ?? e);
  }
}

export function reportConnected(callId: string): void {
  try {
    const uuid = callIdToUuid(callId);
    if (Platform.OS === 'android') {
      RNCallKeep.setCurrentCallActive(uuid);
    }
  } catch {}
}

export function endCall(callId: string): void {
  try {
    const uuid = callIdToUuid(callId);
    RNCallKeep.endCall(uuid);
  } catch {}
}

export function reportEnded(
  callId: string,
  reason: 'failed' | 'declined' | 'unanswered' | 'ended' = 'ended',
): void {
  try {
    const uuid = callIdToUuid(callId);
    const reasonCode =
      reason === 'failed'
        ? CK_CONSTANTS.END_CALL_REASONS.FAILED
        : reason === 'unanswered'
          ? CK_CONSTANTS.END_CALL_REASONS.UNANSWERED
          : reason === 'declined'
            ? CK_CONSTANTS.END_CALL_REASONS.MISSED
            : CK_CONSTANTS.END_CALL_REASONS.REMOTE_ENDED;
    RNCallKeep.reportEndCallWithUUID(uuid, reasonCode);
  } catch {}
}

export { RNCallKeep };