using MeksMathGame.Models;
using ReactiveUI;
using System;
using System.Collections.Generic;
using System.Reactive;

namespace MeksMathGame.ViewModels;

public class GameEngineViewModel : ViewModelBase
{
    public string? _gameText;
    public string? _operation;
    public string? _winLoseText = "";
    public string? _scoreInfo;
    public int? _numberOne;
    public int? _numberTwo;
    public int? _score = 0;
    public double _solution;
    public double _gameSolution;
    public bool _isCorrect;
    public bool _isVisible = false;
    public List<string> operations = new() { "➕", "➖", "✖️", "➗" };

    public GameEngineViewModel(Game game)
    {
        GameText = $"Game: {game.GameType} - Difficulty: {game.Difficulty}";
        ScoreInfo = $"Score: {Score} / {game.TotalQuestions}";
        NumberOne = GetNumber(game.Difficulty);
        NumberTwo = GetNumber(game.Difficulty);
        Operation = GetOperation(game.GameType);
        GameSolution = GetSolution(game.GameType);

        WinLoseText = IsCorrect
            ? "Correct Answer! Great Job!"
            : $"Incorrect Answer! Expected: {GameSolution}";

        IObservable<bool> entryOk = this.WhenAnyValue(
            x => x.Solution,
            x => x >= 0);

        Submit = ReactiveCommand.Create(
            CheckSolution,
            entryOk);

        GoHome = ReactiveCommand.Create(() => { });
    }

    public int GetNumber(string diff)
    {
        Random rnd = new();

        return diff switch
        {
            "Easy" => rnd.Next(0, 300),
            "Medium" => rnd.Next(0, 600),
            "Hard" => rnd.Next(0, 900),
            _ => throw new Exception("Error Getting Random Number")
        };
    }

    public string GetOperation(string gameType)
    {
        Random rnd = new();
        int rndNum = rnd.Next(0, operations.Count);

        return gameType switch
        {
            "Addition" => "➕",
            "Subtraction" => "➖",
            "Multiplication" => "✖️",
            "Division" => "➗",
            "Random" => operations[rndNum],
            _ => throw new Exception("Error Getting Operation")
        };
    }

    public void CheckSolution()
    {
        if (Solution == GameSolution)
        {
            Score++;
            WinLoseText = "Correct Answer! Great Job!";
        }
        else
        {
            WinLoseText = $"Incorrect Answer! Expected: {GameSolution}";
        }

        IsVisible = true;
    }

    public double GetSolution(string gameType)
    {
        return gameType switch
        {
            "Addition" => GameSolution = Convert.ToDouble(NumberOne + NumberTwo),
            "Subtraction" => GameSolution = Convert.ToDouble(NumberOne - NumberTwo),
            "Multiplication" => GameSolution = Convert.ToDouble(NumberOne * NumberTwo),
            "Division" => GameSolution = Convert.ToDouble(NumberOne / NumberTwo),
            _ => throw new Exception("Error Obtaining Solution")
        };
    }

    #region Getters/Setters
    public string? GameText
    {
        get => _gameText;
        set => this.RaiseAndSetIfChanged(ref _gameText, value);
    }

    public string? Operation
    {
        get => _operation;
        set => this.RaiseAndSetIfChanged(ref _operation, value);
    }

    public string WinLoseText
    {
        get => _winLoseText;
        set => this.RaiseAndSetIfChanged(ref _winLoseText, value);
    }

    public string? ScoreInfo
    {
        get => _scoreInfo;
        set => this.RaiseAndSetIfChanged(ref _scoreInfo, value);
    }

    public int? NumberOne
    {
        get => _numberOne;
        set => this.RaiseAndSetIfChanged(ref _numberOne, value);
    }

    public int? NumberTwo
    {
        get => _numberTwo;
        set => this.RaiseAndSetIfChanged(ref _numberTwo, value);
    }

    public int? Score
    {
        get => _score;
        set => this.RaiseAndSetIfChanged(ref _score, value);
    }

    public double Solution
    {
        get => _solution;
        set => this.RaiseAndSetIfChanged(ref _solution, value);
    }

    public double GameSolution
    {
        get => _gameSolution;
        set => this.RaiseAndSetIfChanged(ref _gameSolution, value);
    }

    public bool IsCorrect
    {
        get => _isCorrect;
        set => this.RaiseAndSetIfChanged(ref _isCorrect, value);
    }

    public bool IsVisible
    {
        get => _isVisible;
        set => this.RaiseAndSetIfChanged(ref _isVisible, value);
    }
    #endregion

    public ReactiveCommand<Unit, Unit> Submit { get; }
    public ReactiveCommand<Unit, Unit> GoHome { get; }
}