using System;
using System.Reflection;
using System.Threading.Tasks;
using Kruzya.TelegramBot.Core.Data;
using Kruzya.TelegramBot.Core.Extensions;

namespace Kruzya.TelegramBot.Core.Options;

public class DbOptionProvider : IOptionProvider
{
    private readonly CoreContext _db;

    public DbOptionProvider(CoreContext db)
    {
        _db = db;
    }

    public async Task<TValue> GetValueAsync<TOption, TValue>(long chatId)
    {
        return await GetValueAsync(
            chatId, 
            GetOptionId<TOption>(), 
            GetDefaultValue<TOption, TValue>()
        );
    }

    public async Task<TValue> GetValueAsync<TValue>(long chatId, string optionId, TValue defVal)
    {
        return (await _db.ChatOptionValues.FindOrCreateOption(chatId, optionId)).GetValue(defVal);
    }

    public async Task SetValueAsync<TOption, TValue>(long chatId, TValue value)
    {
        var chatOption = await _db.ChatOptionValues.FindOrCreateOption(chatId, GetOptionId<TOption>());
        chatOption.SetValue(value);
        _db.AddOrUpdate(chatOption);
    }

    protected OptionAttribute GetOptionAttribute<TOption>()
    {
        return typeof(TOption).GetCustomAttribute<OptionAttribute>();
    }

    protected string GetOptionId<TOption>()
    {
        var optionId = GetOptionAttribute<TOption>()?.OptionId;
        if (optionId == null)
        {
            throw new ArgumentException("Option must implement OptionAttribute");
        }
        
        return optionId;
    }

    protected TValue GetDefaultValue<TOption, TValue>()
    {
        return (TValue) GetOptionAttribute<TOption>().DefaultValue;
    }
}