// ==========================================================================
//  Squidex Headless CMS
// ==========================================================================
//  Copyright (c) Squidex UG (haftungsbeschränkt)
//  All rights reserved. Licensed under the MIT license.
// ==========================================================================

using System;
using System.Threading.Tasks;
using Squidex.Domain.Apps.Entities.Assets.Commands;
using Squidex.Infrastructure;
using Squidex.Infrastructure.Assets;
using Squidex.Infrastructure.Commands;
using Squidex.Infrastructure.States;

namespace Squidex.Domain.Apps.Entities.Assets
{
    public sealed class AssetCommandMiddleware : GrainCommandMiddleware<AssetCommand, AssetGrain>
    {
        private readonly IAssetStore assetStore;
        private readonly IAssetThumbnailGenerator assetThumbnailGenerator;

        public AssetCommandMiddleware(
            IStateFactory stateFactory,
            IAssetStore assetStore,
            IAssetThumbnailGenerator assetThumbnailGenerator)
            : base(stateFactory)
        {
            Guard.NotNull(assetStore, nameof(assetStore));
            Guard.NotNull(assetThumbnailGenerator, nameof(assetThumbnailGenerator));

            this.assetStore = assetStore;
            this.assetThumbnailGenerator = assetThumbnailGenerator;
        }

        public async override Task HandleAsync(CommandContext context, Func<Task> next)
        {
            switch (context.Command)
            {
                case CreateAsset createAsset:
                    {
                        createAsset.ImageInfo = await assetThumbnailGenerator.GetImageInfoAsync(createAsset.File.OpenRead());

                        await assetStore.UploadTemporaryAsync(context.ContextId.ToString(), createAsset.File.OpenRead());
                        try
                        {
                            var result = await ExecuteCommandAsync(createAsset) as AssetSavedResult;

                            context.Complete(EntityCreatedResult.Create(createAsset.AssetId, result.Version));

                            await assetStore.CopyTemporaryAsync(context.ContextId.ToString(), createAsset.AssetId.ToString(), result.FileVersion, null);
                        }
                        finally
                        {
                            await assetStore.DeleteTemporaryAsync(context.ContextId.ToString());
                        }

                        break;
                    }

                case UpdateAsset updateAsset:
                    {
                        updateAsset.ImageInfo = await assetThumbnailGenerator.GetImageInfoAsync(updateAsset.File.OpenRead());

                        await assetStore.UploadTemporaryAsync(context.ContextId.ToString(), updateAsset.File.OpenRead());
                        try
                        {
                            var result = await ExecuteCommandAsync(updateAsset) as AssetSavedResult;

                            context.Complete(result);

                            await assetStore.CopyTemporaryAsync(context.ContextId.ToString(), updateAsset.AssetId.ToString(), result.FileVersion, null);
                        }
                        finally
                        {
                            await assetStore.DeleteTemporaryAsync(context.ContextId.ToString());
                        }

                        break;
                    }

                default:
                    await base.HandleAsync(context, next);
                    break;
            }
        }
    }
}