import 'package:flutter/material.dart';
import 'package:outbag_app/backend/request.dart';
import 'package:outbag_app/backend/user.dart';
import 'package:routemaster/routemaster.dart';
import '../backend/resolve_url.dart';
import '../backend/errors.dart';
import 'package:crypto/crypto.dart';
import 'dart:convert';

enum Mode {
  signin,
  signup,
  signupOTA,
}

class AuthPage extends StatefulWidget {
  final Mode mode;
  const AuthPage({super.key, this.mode = Mode.signin});

  @override
  State<StatefulWidget> createState() => _AuthPageState();
}

class _AuthPageState extends State<AuthPage> {
  final TextEditingController _ctrServer = TextEditingController();
  final TextEditingController _ctrUsername = TextEditingController();
  final TextEditingController _ctrPassword = TextEditingController();
  final TextEditingController _ctrPasswordRpt = TextEditingController();
  final TextEditingController _ctrOTA = TextEditingController();

  bool showSpinner = false;

  @override
  Widget build(BuildContext context) {
    String modeName = "Sign In";
    if (widget.mode != Mode.signin) {
      modeName = "Sign Up";
    }
    String modeDescription = "Log into account";
    if (widget.mode != Mode.signin) {
      modeDescription = "Create new account";
    }

    final textTheme = Theme.of(context)
        .textTheme
        .apply(displayColor: Theme.of(context).colorScheme.onSurface);

    return showSpinner
        ? Scaffold(
            body: Center(
                child: Column(
                    crossAxisAlignment: CrossAxisAlignment.center,
                    mainAxisAlignment: MainAxisAlignment.center,
                    children: [
                const CircularProgressIndicator(),
                Text('Loading', style: textTheme.titleLarge),
              ])))
        : Scaffold(
            appBar: AppBar(
              title: Text(modeName),
              leading: IconButton(
                onPressed: () {
                  // go back
                  Routemaster.of(context).history.back();
                },
                icon: const Icon(Icons.arrow_back),
                tooltip: "Go back",
              ),
            ),
            body: Center(
                child: Flexible(
                    child: ConstrainedBox(
                        constraints: const BoxConstraints(maxWidth: 400),
                        child: Column(
                          crossAxisAlignment: CrossAxisAlignment.center,
                          mainAxisAlignment: MainAxisAlignment.center,
                          children: [
                            Padding(
                              padding: const EdgeInsets.all(8),
                              child: TextField(
                                controller: _ctrServer,
                                keyboardType: TextInputType.url,
                                decoration: const InputDecoration(
                                  prefixIcon: Icon(Icons.dns),
                                  labelText: 'Server',
                                  hintText: 'Your homeserver url',
                                  helperText:
                                      'Your data will be stored on your homeserver',
                                  border: OutlineInputBorder(),
                                ),
                              ),
                            ),
                            Padding(
                              padding: const EdgeInsets.all(8),
                              child: TextField(
                                controller: _ctrUsername,
                                keyboardType: TextInputType.emailAddress,
                                decoration: const InputDecoration(
                                  prefixIcon: Icon(Icons.person),
                                  labelText: 'Username',
                                  hintText: 'Your username',
                                  helperText:
                                      'your username and server tag allow others to identify you',
                                  border: OutlineInputBorder(),
                                ),
                              ),
                            ),
                            Padding(
                              padding: const EdgeInsets.all(8),
                              child: TextField(
                                controller: _ctrPassword,
                                keyboardType: TextInputType.visiblePassword,
                                obscureText: true,
                                decoration: const InputDecoration(
                                  prefixIcon: Icon(Icons.lock),
                                  labelText: 'Password',
                                  hintText: 'Your password',
                                  helperText:
                                      'Password have to be at least six characters long',
                                  border: OutlineInputBorder(),
                                ),
                              ),
                            ),
                            // ONLY SIGNUP
                            ...((widget.mode != Mode.signin)
                                ? [
                                    Padding(
                                      padding: const EdgeInsets.all(8),
                                      child: TextField(
                                        controller: _ctrPasswordRpt,
                                        keyboardType:
                                            TextInputType.visiblePassword,
                                        obscureText: true,
                                        decoration: const InputDecoration(
                                          prefixIcon: Icon(Icons.lock),
                                          labelText: 'Repeat Password',
                                          hintText: 'Type your password again',
                                          helperText:
                                              'Make sure to type the correct password',
                                          border: OutlineInputBorder(),
                                        ),
                                      ),
                                    )
                                  ]
                                : []),
                            // ONLY SIGNUP OTA
                            ...((widget.mode == Mode.signupOTA)
                                ? [
                                    Padding(
                                      padding: const EdgeInsets.all(8),
                                      child: TextField(
                                        controller: _ctrOTA,
                                        keyboardType:
                                            TextInputType.visiblePassword,
                                        decoration: const InputDecoration(
                                          prefixIcon: Icon(Icons.key),
                                          labelText: 'OTA',
                                          hintText:
                                              'One-Time-Authorization token',
                                          helperText:
                                              'This token might be required if the server is rate limited',
                                          border: OutlineInputBorder(),
                                        ),
                                      ),
                                    )
                                  ]
                                : []),
                          ],
                        )))),
            floatingActionButton: FloatingActionButton.extended(
              onPressed: () async {
                setState(() {
                  showSpinner = true;
                });

                // verify that both passwords are the same
                if (widget.mode != Mode.signin) {
                  if (_ctrPassword.text != _ctrPasswordRpt.text) {
                    setState(() {
                      showSpinner = false;
                    });

                    final snackBar = SnackBar(
                      behavior: SnackBarBehavior.floating,
                      content: const Text('Passwords do not match'),
                      action: SnackBarAction(
                        label: 'Dismiss',
                        onPressed: () {
                          ScaffoldMessenger.of(context).hideCurrentSnackBar();
                        },
                      ),
                    );

                    ScaffoldMessenger.of(context).hideCurrentSnackBar();
                    ScaffoldMessenger.of(context).showSnackBar(snackBar);

                    _ctrPasswordRpt.clear();
                    return;
                  }
                }

                // password has to be at least 6 characters long
                if (_ctrPassword.text.length < 6) {
                  setState(() {
                    showSpinner = false;
                  });

                  final snackBar = SnackBar(
                    behavior: SnackBarBehavior.floating,
                    content: const Text(
                        'Password has to be at least 6 characters long'),
                    action: SnackBarAction(
                      label: 'Dismiss',
                      onPressed: () {
                        ScaffoldMessenger.of(context).hideCurrentSnackBar();
                      },
                    ),
                  );

                  ScaffoldMessenger.of(context).hideCurrentSnackBar();
                  ScaffoldMessenger.of(context).showSnackBar(snackBar);

                  _ctrPasswordRpt.clear();
                  return;
                }

                final scaffMgr = ScaffoldMessenger.of(context);

                // TODO: resolve homeserver url
                OutbagServer server;
                try {
                  server = await getOutbagServerUrl(_ctrServer.text);
                } catch (e) {
                  // unable to find outbag server
                  // at given server address
                  // stop authentification
                  setState(() {
                    showSpinner = false;
                  });

                  final snackBar = SnackBar(
                    behavior: SnackBarBehavior.floating,
                    content: Text(
                      'Unable to find valid outbag server on ${_ctrServer.text}'),
                    action: SnackBarAction(
                      label: 'Dismiss',
                      onPressed: () {
                        scaffMgr.hideCurrentSnackBar();
                      },
                    ),
                  );

                  scaffMgr.hideCurrentSnackBar();
                  scaffMgr.showSnackBar(snackBar);

                  return;
                }

                var bytes = utf8.encode(_ctrPassword.text);
                final password = sha256.convert(bytes).toString();
                try {
                  Response resp;
                  // validate account
                  if (widget.mode == Mode.signin) {
                    resp = await postUnauthorized(
                        target: server,
                        path: 'signin',
                        body: {
                          'name': _ctrUsername.text,
                          'server': server.tag,
                          'accountKey': password
                        });
                  } else if (widget.mode == Mode.signup) {
                    resp = await postUnauthorized(
                        target: server,
                        path: 'signup',
                        body: {
                          'name': _ctrUsername.text,
                          'server': server.tag,
                          'accountKey': password
                        });
                  } else {
                    // signup OTA
                    resp = await postUnauthorized(
                        target: server,
                        path: 'signupOTA',
                        body: {
                          'name': _ctrUsername.text,
                          'server': server.tag,
                          'accountKey': password,
                          'OTA': _ctrOTA.text
                        });
                  }

                  if (resp.res == Result.err) {
                    // error
                    final snackBar = SnackBar(
                      behavior: SnackBarBehavior.floating,
                      content: Text(errorAsString(resp.body)),
                      action: SnackBarAction(
                        label: 'Dismiss',
                        onPressed: () {
                          scaffMgr.hideCurrentSnackBar();
                        },
                      ),
                    );

                    scaffMgr.hideCurrentSnackBar();
                    scaffMgr.showSnackBar(snackBar);
                  } else {
                    // authorize user
                    await User(
                            username: _ctrUsername.text,
                            password: password,
                            server: server)
                        .toDisk();
                  }
                } catch (_) {
                  final snackBar = SnackBar(
                    behavior: SnackBarBehavior.floating,
                    content: const Text('Network error'),
                    action: SnackBarAction(
                      label: 'Dismiss',
                      onPressed: () {
                        scaffMgr.hideCurrentSnackBar();
                      },
                    ),
                  );

                  scaffMgr.hideCurrentSnackBar();
                  scaffMgr.showSnackBar(snackBar);
                }

                setState(() {
                  showSpinner = false;
                });
              },
              label: Text(modeName),
              icon: const Icon(Icons.check),
              tooltip: modeDescription,
            ),
          );
  }
}