kmobile/lib/features/auth/screens/sms_verification_helper.dart

// lib/features/auth/screens/sms_verification_helper.dart

import 'package:flutter/material.dart';
import 'package:kmobile/api/services/send_sms_service.dart';
import 'package:permission_handler/permission_handler.dart';
import 'package:uuid/uuid.dart';

class SmsVerificationHelper {
  final SmsService _smsService = SmsService();

  Future<void> _showRestrictedSmsDialog(BuildContext context) async {
    await showDialog(
      context: context,
      builder: (context) => AlertDialog(
        title: const Text("SMS Permission Restricted"),
        content: const SingleChildScrollView(
          child: Column(
            crossAxisAlignment: CrossAxisAlignment.start,
            children: [
              Text("It seems your device is restricting this app from sending SMS messages, which is required for verification. Please follow these steps to enable it:\n"),
              Text("1. Open your device Settings.", style: TextStyle(fontWeight: FontWeight.bold)),
              Text("2. Go to 'Apps' or 'Apps & notifications'."),
              Text("3. Find and tap on this app ('KMobile')."),
              Text("4. Tap on the three dots (⋮) in the top right corner."),
              Text("5. Select 'Allow restricted settings' and confirm. This is crucial to allow SMS permission."),
              Text("6. Now you have two options to allow SMS permission:"),
              Text("   a. Tap on 'Permissions', then find 'SMS' is set to 'Allow'."),
              Text("   b. Alternatively, you can return to the KMobile app, and the SMS permission pop-up should appear again, allowing you to grant it directly."),
              Text("\nSome devices have an additional setting for 'Premium SMS'. If the above doesn't work, look for a 'Premium SMS access' setting (you can search for it in your Settings app) and set it to 'Always Allow' for this app.\n"),
              Text("After you've enabled the permission, please come back to the app."),
            ],
          ),
        ),
        actions: [
          TextButton(
            child: const Text("I've Enabled It"),
            onPressed: () => Navigator.of(context).pop(),
          ),
          TextButton(
            child: const Text("Open Settings"),
            onPressed: () {
              openAppSettings();
              Navigator.of(context).pop();
            },
          ),
        ],
      ),
    );
  }

  void _showSnackBar(BuildContext context, String message) {
    ScaffoldMessenger.of(context).showSnackBar(
      SnackBar(
        content: Text(message),
        duration: const Duration(seconds: 3),
      ),
    );
  }

  Future<void> initiateSmsSequence({
    required BuildContext context,
  }) async {
    bool hasPermission = false;

    // --- PERMISSION LOOP ---
    while (!hasPermission) {
      final status = await _smsService.handleSmsPermission();

      switch (status) {
        case PermissionStatusResult.granted:
          _showSnackBar(context, "Permissions Granted! Proceeding...");
          hasPermission = true; // This will break the loop
          break;
        case PermissionStatusResult.denied:
          _showSnackBar(context, "SMS and Phone permissions are required. Please try again.");
          await Future.delayed(const Duration(seconds: 3));
          break;
        case PermissionStatusResult.permanentlyDenied:
          await showDialog(
            context: context,
            builder: (context) => AlertDialog(
              title: const Text("Permission Required"),
              content: const Text("SMS and Phone permissions are required for device verification. Please enable them in your app settings to continue."),
              actions: [
                TextButton(
                  child: const Text("Cancel"),
                  onPressed: () => Navigator.of(context).pop(),
                ),
                TextButton(
                  child: const Text("Open Settings"),
                  onPressed: () {
                    openAppSettings(); // Opens the phone's settings screen for this app
                    Navigator.of(context).pop();
                  },
                ),
              ],
            ),
          );
          // Wait for user to return from settings
          await Future.delayed(const Duration(seconds: 5));
          break;
        case PermissionStatusResult.restricted:
          await _showRestrictedSmsDialog(context);
          // Wait for user to return from settings
          await Future.delayed(const Duration(seconds: 10));
          break;
      }
    }

    // --- SMS SENDING LOOP ---
    bool isSmsSent = false;
    while (!isSmsSent) {
      var uuid = const Uuid();
      String uniqueId = uuid.v4();
      String smsMessage = uniqueId;
      _showSnackBar(context, "Attempting to send verification SMS...");
      isSmsSent = await _smsService.sendVerificationSms(
        context: context,
        destinationNumber: '9580079717', // Replace with your number
        message: smsMessage,
      );
      if (isSmsSent) {
        _showSnackBar(context, "SMS sent successfully! Proceeding to login.");
        break;
      } else {
        _showSnackBar(context, "SMS failed to send. Retrying in 5 seconds...");
        await Future.delayed(const Duration(seconds: 5));
      }
    }
  }
}