using System.Data;
using System.Text.Json;
using riff;

public class MysteriousCube : IRCBot
{
    private HttpClient RequestClient = new();
    private const string AllTriviaQuestionsPath = "data/TriviaQuestions.json";
    private const string UnaskedTriviaQuestionsPath = "data/UnaskedTriviaQuestions.json";
    private TriviaQuestion[] AllTriviaQuestions;
    private List<TriviaQuestion> UnaskedTriviaQuestions;
    private bool ListeningForAnswer = false;
    private TriviaQuestion? CurrentQuestion = null;
    private Random Rand = new();

    public MysteriousCube(string host, int port, string nick, string realname, List<string> permanentChannels) 
        : base(host, port, nick, realname, permanentChannels)
    {
        AllTriviaQuestions = LoadAllQuestions();
        UnaskedTriviaQuestions = LoadUnaskedQuestions();

        (string, Action<PRIVMSG>)[] commands = [
            ("echo", Echo),
            ("trivia", PostQuestion)
        ];

        Action<PRIVMSG>[] listeners = [
            AnswerListener
        ];

        HookCommands(commands);
        HookListeners(listeners);
    }

    private void Echo(PRIVMSG privmsg)
    {
        SendPrivmsg(privmsg.Sender, privmsg.Body);
    }

    private void PostQuestion(PRIVMSG privmsg)
    {
        var question = GetQuestion();
        CurrentQuestion = question;
        ListeningForAnswer = true;
        SendPrivmsg(privmsg.Sender, $"Answer 'true' or 'false': {question.Question}");
    }

    private void AnswerListener(PRIVMSG privmsg)
    {
        if (!ListeningForAnswer || CurrentQuestion == null)
            return;
        string line = privmsg.Body.ToLower().Trim();
        bool? answer = null;
        if (line.StartsWith("true"))
            answer = true;
        else if (line.StartsWith("false"))
            answer = false;
        else
            return;
        ListeningForAnswer = false;
        string response;
        if (answer == CurrentQuestion.Answer)
            response = $"{privmsg.Nick} is correct!";
        else
            response = $"{privmsg.Nick} is wrong!";
        CurrentQuestion = null;
        SendPrivmsg(privmsg.Sender, response);
    }

    private TriviaQuestion GetQuestion()
    {
        if (UnaskedTriviaQuestions.Count == 0)
            UnaskedTriviaQuestions = AllTriviaQuestions.ToList();
        TriviaQuestion question = UnaskedTriviaQuestions[Rand.Next(UnaskedTriviaQuestions.Count)];
        UnaskedTriviaQuestions.Remove(question);
        File.WriteAllText(UnaskedTriviaQuestionsPath, JsonSerializer.Serialize(UnaskedTriviaQuestions));
        return question;
    }

    private TriviaQuestion[] LoadAllQuestions()
    {
        try
        {
            using (FileStream stream = File.OpenRead(AllTriviaQuestionsPath))
            {
                TriviaQuestion[] questions = JsonSerializer.Deserialize<TriviaQuestion[]>(stream)!;
                if (questions == null)
                    throw new NoNullAllowedException();
                return questions;
            }
        }
        catch (FileNotFoundException)
        {
            Console.WriteLine("Trivia questions not downloaded. Use download_trivia.py script.");
            Environment.Exit(1);
            return Array.Empty<TriviaQuestion>(); // Unreachable, but required for compiler
        }
    }

    private List<TriviaQuestion> LoadUnaskedQuestions()
    {
        try
        {
            using (FileStream stream = File.OpenRead(UnaskedTriviaQuestionsPath))
            {
                List<TriviaQuestion> questions = JsonSerializer.Deserialize<List<TriviaQuestion>>(stream)!;
                if (questions == null)
                    throw new NoNullAllowedException();
                return questions;
            }
        }
        catch (FileNotFoundException)
        {
            return AllTriviaQuestions.ToList();
        }
    }
}

public class TriviaQuestion
{
    public required string Question { get; set; }
    public required bool Answer { get; set; }
}