using FileService.Application.Ports;
using FileService.Domain.IReposities;
using IM.Application.Abstractions;
using IM.Commons.IntegrationEvents;
using MassTransit;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace FileService.Application.EventHandler
{
    public class UploadTaskCompleteEventHandler : IConsumer<UploadTaskCompleteEvent>
    {
        private readonly IObjectStorageRouter router;
        private readonly IUploadFileReposity uploadFile;
        private readonly IUnitOfWork uwork;
        private readonly IUploadTaskReposity uploadTask;

        public UploadTaskCompleteEventHandler(IObjectStorageRouter router, IUploadFileReposity uploadFile, IUploadTaskReposity uploadTask, IUnitOfWork uwork)
        {
            this.router = router;
            this.uploadFile = uploadFile;
            this.uwork = uwork;
            this.uploadTask = uploadTask;
        }

        public async Task Consume(ConsumeContext<UploadTaskCompleteEvent> context)
        {
            var @event = context.Message;
            var existingFile = await uploadFile.FindBySourceTaskIdAsync(@event.TaskId);
            if (existingFile != null)
            {
                return;
            }

            var task = await uploadTask.FindByIdAsync(@event.TaskId);
            if (task is null)
            {
                throw new InvalidOperationException($"Upload task {@event.TaskId} has not been committed yet.");
            }

            var storage = router.Route(@event.ProviderCode);
            try
            {
                await storage.CompleteUploadAsync(new StorageContracts.CompleteUploadCommand(
                    ProviderCode: @event.ProviderCode,
                    Bucket: @event.Bucket,
                    Region: @event.Region,
                    ObjectKey: @event.ObjectKey,
                    UploadSessionId: @event.SessionId,
                    Parts: @event.Parts.Select(s => new StorageContracts.UploadPart(
                            PartNumber: s.PartNumber,
                            ETag: s.ETag,
                            Size: s.Size,
                            Checksum: s.Checksum
                        )).ToList()
                    ), context.CancellationToken);
                var file = new Domain.Entities.UploadFile(
                    ownerId: @event.OperatorId,
                    fileName: @event.FileName,
                    fileSize: @event.FileSize,
                    contentType: @event.ContentType,
                    new Domain.ValueObjects.StorageLocation(@event.ProviderCode, @event.Bucket, @event.ObjectKey, @event.Region),
                    checkSum: new Domain.ValueObjects.CheckSum("md5", @event.CheckSun),
                    sourceTaskId: @event.TaskId,
                    chatType: @event.ChatType,
                    targetId: @event.TargetId,
                    isPublic: false
                    );
                uploadFile.Create(file);
                task.CompleteUpload(file.Id);
                await uwork.SaveChangesAsync(context.CancellationToken);
            }
            catch (Exception ex)
            {
                task.Fail(ex.Message);
                await uwork.SaveChangesAsync(context.CancellationToken);
                throw;
            }
        }
    }
}