#nullable enable
using System.Linq;
using System.Threading.Tasks;
using Kruzya.TelegramBot.Core.Data;
using Kruzya.TelegramBot.Core.Extensions;
using Microsoft.EntityFrameworkCore;

namespace Kruzya.TelegramBot.Core.Option;

public class CoreContextStorageService : IOptionStorageAdapter
{
    private CoreContext _db;
    public CoreContextStorageService(CoreContext db)
    {
        _db = db;
    }

    public async Task<byte[]?> LoadValueAsync(IOptionKey key)
    {
        var entity = await BuildQueryForKey(key).FirstOrDefaultAsync();

        return entity?.Value;
    }

    public async Task SaveValueAsync(IOptionKey key, byte[] value)
    {
         var entity = await BuildQueryForKey(key).FirstOrDefaultAsync();
         if (entity == null)
         {
             entity = await CreateEntity(key);
         }

         entity.Value = value;
         _db.AddOrUpdate(entity);
    }

    private IQueryable<BotUserValue> BuildQueryForKey(IOptionKey key)
    {
        var legacyUserId = key.UserId ?? 0;

        return _db.UserValues.Where(e => e.BotUser.ChatId == key.ChatId && e.BotUser.UserId == legacyUserId
                                                                        && e.Name == key.Identifier);
    }

    private async Task<BotUserValue> CreateEntity(IOptionKey key)
    {
        var entity = _db.UserValues.Create()!;
        entity.BotUser = await _db.Users.FindOrCreate(key.ChatId, key.UserId ?? 0);
        return entity;
    }
}