class _LevelOneState extends State<LevelOnePage> {
  late Timer time;
  int tick = 0;
  @override
  void initState() {
    super.initState();
    time = Timer.periodic(const Duration(seconds: 1), updateTick);
  }

  void updateTick(Timer timer) {
    setState(() {
      tick++;
      if (tick == 15) {
        time.cancel();
        Navigator.of(context)
            .push(MaterialPageRoute(builder: (BuildContext context) {
          return const StartPage();
        }));
      }
    });
  }

  List<String> numberPad = [
    '7',
    '8',
    '9',
    'C',
    '4',
    '5',
    '6',
    'DEL',
    '1',
    '2',
    '3',
    '=',
    '0',
  ];
  // Question
  int numberA = 1;
  int numberB = 1;
  // Answer
  String userAnswer = '';
  // On Button Tapped
  void buttonTapped(String button) {
    setState(
      () {
        if (button == '=') {
          //Check if user is correct
          // TODO: YOU NEED TO HAVE A SYMBOL THAT IS BEING USED SOMEPLACE, DOESN"T LOOK LIKE YOU HAVE ONE, JUST A METHOD TO GET ONE
          checkResult( '+', numberA, numberB, double.parse(userAnswer));
        } else if (button == 'C') {
          // CLears answer input
          userAnswer = '';
        } else if (button == 'DEL') {
          // Deletes the last user input
          if (userAnswer.isNotEmpty) {
            userAnswer = userAnswer.substring(0, userAnswer.length - 1);
          }
          // Caps at 3 Numbers
        } else if (userAnswer.length < 3) {
          userAnswer += button;
        }
      },
    );
  }

  bool isAnswerCorrect(String op, int numberA, int numberB, double answer) {
    switch (op) {
      case '+':
        return answer == numberA + numberB;
      case '-':
        return answer == numberA - numberB;
      case '/':
        return answer == numberA / numberB;
      case '*':
        return answer == numberA * numberB;
      default:
        return false;
    }
  }

  //check if user is right
  void checkResult(String op, int numberA, int numberB, double answer) {
   if(isAnswerCorrect(op, numberA, numberB, answer)) {
      // If correct
      showDialog(
        context: context,
        builder: (context) {
          return  ResultMessage(
            message: 'Correct  ',
            onTap: goToNextQuestion,
            icon: Icons.arrow_forward,
          );
        },
      );
    } else{
      // ignore: avoid_print
      showDialog(
        context: context,
        builder: (context) {
          return  ResultMessage(
              message: 'Sorry Try Again',
              onTap: goBackToQuestion,
              icon: Icons.rotate_left);
        },
      );
    }
}

// Create Random Number
  var randomNumber = Random();
  // Create Random Symbol
  String createRandomSymbol() {
    var symbols = ['+', '-', '*', '/'];
    symbols.shuffle();
    return symbols.first;
  }

  // GoToNextQuestion
  void goToNextQuestion() {
    //Dimiss
    Navigator.of(context).pop();
    //Value Reset
    setState(() {
      userAnswer = '';
    });
    //New Question
    numberA = randomNumber.nextInt(12);
    numberB = randomNumber.nextInt(12);
  }

  //goBackToQuestion
  void goBackToQuestion() {
    Navigator.of(context).pop();
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      backgroundColor: Colors.lightGreenAccent,
      body: Column(
        children: <Widget>[
          Expanded(
            child: Container(
              child: Column(
                  mainAxisAlignment: MainAxisAlignment.spaceEvenly,
                  children: <Widget>[
                    Container(
                      padding: const EdgeInsets.all(
                        25,
                      ),
                      alignment: Alignment.centerRight,
                      child: Text(tick.toString(),
                          textAlign: TextAlign.right, style: basicTextStyle),
                    ),
                  ]),
            ),
          ),
          Container(
            padding: const EdgeInsets.all(15),
            alignment: Alignment.bottomCenter,
            child:
                //Question
                Text(
              // ignore: prefer_interpolation_to_compose_strings
              numberA.toString() + ' + ' + numberB.toString() + ' = ',
              style: const TextStyle(fontSize: 32, color: Colors.purpleAccent),
            ),
          ),
          Container(
            height: 55,
            width: 110,
            decoration: BoxDecoration(
              color: Colors.deepPurpleAccent,
              borderRadius: BorderRadius.circular(4),
            ),
            child: Center(
              child: Text(userAnswer, style: basicTextStyle),
            ),
          ),
          Expanded(
            flex: 3,
            child: Container(
              child: GridView.builder(
                itemCount: numberPad.length,
                physics: const NeverScrollableScrollPhysics(),
                gridDelegate: const SliverGridDelegateWithFixedCrossAxisCount(
                    crossAxisCount: 4),
                itemBuilder: (BuildContext context, int index) {
                  return MyButton(
                    child: numberPad[index],
                    onTap: () => buttonTapped(numberPad[index]),
                  );
                },
              ),
            ),
          ),
        ],
      ),
    );
  }
}