anyway/frontend/lib/pages/settings.dart

import 'package:anyway/constants.dart';
import 'package:anyway/main.dart';
import 'package:flutter/material.dart';
import 'package:permission_handler/permission_handler.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'package:url_launcher/url_launcher.dart';


bool debugMode = false;

class SettingsPage extends StatefulWidget {
  @override
  _SettingsPageState createState() => _SettingsPageState();
}

class _SettingsPageState extends State<SettingsPage> {
  @override
  Widget build(BuildContext context) {
    return ListView(
      padding: EdgeInsets.all(15),
      children: [
        // First a round, centered image
        Center(
          child: CircleAvatar(
            radius: 75,
            child: Icon(Icons.settings, size: 100),
          )
        ),
        Center(
          child: Text('Global settings', style: TextStyle(fontSize: 24))
        ),

        Divider(indent: 25, endIndent: 25, height: 50),

        darkMode(),
        setLocationUsage(),
        setDebugMode(),

        Divider(indent: 25, endIndent: 25, height: 50),

        privacyInfo(),
      ]
    );
  }

  Widget setDebugMode() {
    return Row(
      children: [
        Text('Debugging: use a custom API URL'),
        // white space
        Spacer(),
        Switch(
          value: debugMode,
          onChanged: (bool? newValue) {
            setState(() {
              debugMode = newValue!;
              if (debugMode) {
                showDialog(
                  context: context,
                  builder: (BuildContext context) {
                    return AlertDialog(
                      title: Text('Debug mode - use a custom API endpoint'),
                      content: TextField(
                        controller: TextEditingController(text: API_URL_DEBUG),
                        onChanged: (value) {
                          setState(() {
                            API_URL_BASE = value;
                          });
                        },
                      ),
                      actions: [
                        TextButton(
                          child: Text('OK'),
                          onPressed: () {
                            Navigator.of(context).pop();
                          },
                        ),
                      ],
                    );
                  }
                );
              }
            });
          }
        )
      ],
    );
  }

  Widget darkMode() {
    return Row(
      children: [
        Text('Dark mode'),
        Spacer(),
        Switch(
          value: Theme.of(context).brightness == Brightness.dark,
          onChanged: (bool? newValue) {
            setState(() {
              rootScaffoldMessengerKey.currentState!.showSnackBar(
                SnackBar(content: Text('Dark mode is not implemented yet'))
              );
              // if (newValue!) {
              //   // Dark mode
              //   Theme.of(context).brightness = Brightness.dark;
              // } else {
              //   // Light mode
              //   Theme.of(context).brightness = Brightness.light;
              // }
            });
          }
        )
      ],
    );
  }

  Widget setLocationUsage() {
    Future<SharedPreferences> preferences = SharedPreferences.getInstance();
    return Row(
      children: [
        Text('Use location services'),
        // white space
        Spacer(),
        FutureBuilder(
          future: preferences,
          builder: (context, snapshot) {
            if (snapshot.hasData) {
              bool useLocation = snapshot.data!.getBool('useLocation') ?? false;
              return Switch(
                value: useLocation,
                onChanged: setUseLocation,
              );
            } else {
              return CircularProgressIndicator();
            }
          }
        )
      ],
    );
  }

  void setUseLocation(bool newValue) async {
    await Permission.locationWhenInUse
      .onDeniedCallback(() {
        rootScaffoldMessengerKey.currentState!.showSnackBar(
          SnackBar(content: Text('Location services are required for this feature'))
        );
      })
      .onGrantedCallback(() {
        rootScaffoldMessengerKey.currentState!.showSnackBar(
          SnackBar(content: Text('Location services are now enabled'))
        );
        SharedPreferences.getInstance().then(
          (SharedPreferences prefs) {
            setState(() {
              prefs.setBool('useLocation', newValue);
            });
          }
        );
      })
      .onPermanentlyDeniedCallback(() {
        rootScaffoldMessengerKey.currentState!.showSnackBar(
          SnackBar(content: Text('Location services are required for this feature'))
        );
      })  
    .request();
  }

  Widget privacyInfo() {
    return Center(
      child: Column(
        children: [
          Text('Our privacy policy is available under:'),
          
          TextButton.icon(
            icon: Icon(Icons.info),
            label: Text(PRIVACY_URL),
            onPressed: () async{
              await launchUrl(Uri.parse(PRIVACY_URL));
            }
          )
        ],
      )
    );
  }

}