﻿// The MIT License (MIT)
// 
// Copyright (c) 2015-2018 Rasmus Mikkelsen
// Copyright (c) 2015-2018 eBay Software Foundation
// https://github.com/eventflow/EventFlow
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy of
// this software and associated documentation files (the "Software"), to deal in
// the Software without restriction, including without limitation the rights to
// use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
// the Software, and to permit persons to whom the Software is furnished to do so,
// subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
// FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
// COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
// IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
// CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

using System;
using System.Linq;
using System.Reflection;
using System.Threading;
using System.Threading.Tasks;
using EventFlow.Extensions;
using EventFlow.Logs;

namespace EventFlow.ReadStores
{
    public class ReadModelFactory<TReadModel> : IReadModelFactory<TReadModel>
        where TReadModel : IReadModel
    {
        private readonly ILog _log;

        static ReadModelFactory()
        {
            var type = typeof(TReadModel).GetTypeInfo();

            var emptyConstructor = type
                .GetConstructors()
                .Where(c => !c.GetParameters().Any())
                .ToList();

            if (!emptyConstructor.Any())
            {
                throw new ArgumentException(
                    $"Read model type '{typeof(TReadModel).PrettyPrint()}' doesn't have an empty "+
                    $"constructor. Please create a custom '{typeof(IReadModelFactory<TReadModel>).PrettyPrint()}' "+
                    "implementation.");
            }
        }

        public ReadModelFactory(
            ILog log)
        {
            _log = log;
        }

        public Task<TReadModel> CreateAsync(string id, CancellationToken cancellationToken)
        {
            _log.Verbose(() => $"Creating new instance of read model type '{typeof(TReadModel).PrettyPrint()}' with ID '{id}'");

            var readModel = (TReadModel) Activator.CreateInstance(typeof(TReadModel));

            return Task.FromResult(readModel);
        }
    }
}