using System;
using System.Collections;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using Luticate2.Auth.Utils.Dbo;
using Luticate2.Auth.Utils.Dbo.Fields;
using Luticate2.Auth.Utils.Dbo.Result;
using Luticate2.Auth.Utils.Interfaces;

namespace Luticate2.Auth.Utils.Business.ObjectConverter
{
    public abstract class LuObjectConverterLists : ILuObjectConverter
    {
        protected IServiceProvider ServiceProvider { get; }

        public LuObjectConverterLists(IServiceProvider serviceProvider)
        {
            ServiceProvider = serviceProvider;
        }

        protected abstract Type GetListType();

        public LuResult<object> Convert(object srcObj, LuPartialFieldsDbo fields, ILuObjectConverterOptions options)
        {
            if (srcObj is IEnumerable enumerable)
            {
                var listType = GetListType();
                var listTypeTo = options.TypeConverter.ConvertType(srcObj.GetType().GetGenericArguments()[0]);
                var glistType = listType.MakeGenericType(listTypeTo);
                var collection = options.Allocator.GetInstance(glistType);
                foreach (var obj in enumerable)
                {
                    object convertedObj = null;
                    if (obj != null)
                    {
                        var typeFrom = obj.GetType();
                        var typeTo = options.TypeConverter.ConvertType(typeFrom);
                        // TODO Handle converter == null
                        var converter = LuObjectConverterUtils.GetObjectConverter(ServiceProvider, typeFrom, typeTo);
                        var convertResult = converter.Convert(obj, fields, options);
                        if (!convertResult)
                        {
                            return convertResult;
                        }

                        convertedObj = convertResult.Data;
                    }

                    var methodInfo = collection.GetType().GetMethod(nameof(ICollection<object>.Add));
                    methodInfo.Invoke(collection, new []{convertedObj});
                }

                return LuResult<object>.Ok(collection);
            }
            else
            {
                return LuResult<object>.Error(LuStatus.InputError.ToInt(), $"Could not convert {nameof(srcObj)} to {nameof(IEnumerable)}");
            }
        }
    }

    public class LuObjectConverterList : LuObjectConverterLists
    {
        public LuObjectConverterList(IServiceProvider serviceProvider) : base(serviceProvider)
        {
        }

        protected override Type GetListType()
        {
            return typeof(List<>);
        }
    }

    public class LuObjectConverterCollection : LuObjectConverterLists
    {
        public LuObjectConverterCollection(IServiceProvider serviceProvider) : base(serviceProvider)
        {
        }

        protected override Type GetListType()
        {
            return typeof(Collection<>);
        }
    }
}