using System.Drawing.Imaging;
using System.IO;
using System.Net;
using Azaion.Common.Database;
using Azaion.Common.DTO;
using Azaion.Common.DTO.Config;
using Azaion.Common.DTO.Queue;
using Azaion.CommonSecurity.DTO;
using Azaion.CommonSecurity.Services;
using LinqToDB;
using MediatR;
using MessagePack;
using Microsoft.Extensions.Options;
using Newtonsoft.Json;
using RabbitMQ.Stream.Client;
using RabbitMQ.Stream.Client.Reliable;

namespace Azaion.Common.Services;

public class AnnotationService
{
    private readonly AzaionApiClient _apiClient;
    private readonly IDbFactory _dbFactory;
    private readonly FailsafeAnnotationsProducer _producer;
    private readonly IGalleryService _galleryService;
    private readonly IMediator _mediator;
    private readonly QueueConfig _queueConfig;
    private Consumer _consumer = null!;

    public AnnotationService(AzaionApiClient apiClient,
        IDbFactory dbFactory,
        FailsafeAnnotationsProducer producer,
        IOptions<QueueConfig> queueConfig,
        IGalleryService galleryService,
        IMediator mediator)
    {
        _apiClient = apiClient;
        _dbFactory = dbFactory;
        _producer = producer;
        _galleryService = galleryService;
        _mediator = mediator;
        _queueConfig = queueConfig.Value;

        Task.Run(async () => await Init()).Wait();
    }

    private async Task Init()
    {
        var consumerSystem = await StreamSystem.Create(new StreamSystemConfig
        {
            Endpoints = new List<EndPoint>{new DnsEndPoint(_queueConfig.Host, _queueConfig.Port)},
            UserName = _queueConfig.ConsumerUsername,
            Password = _queueConfig.ConsumerPassword
        });
        _consumer = await Consumer.Create(new ConsumerConfig(consumerSystem, Constants.MQ_ANNOTATIONS_QUEUE)
        {
            OffsetSpec = new OffsetTypeFirst(),
            MessageHandler = async (stream, _, _, message) =>
                await Consume(MessagePackSerializer.Deserialize<AnnotationCreatedMessage>(message.Data.Contents)),
        });
    }

    //AI / Manual
    public async Task SaveAnnotation(string fName, string imageExtension, List<Detection> detections, SourceEnum source, Stream? stream = null, CancellationToken token = default) =>
        await SaveAnnotationInner(DateTime.UtcNow, fName, imageExtension, detections, source, stream, _apiClient.User.Role, _apiClient.User.Email, token);

    //Queue (only from operators)
    public async Task Consume(AnnotationCreatedMessage message, CancellationToken cancellationToken = default)
    {
        if (message.CreatedRole == RoleEnum.Validator) //Don't proceed our own messages (or from another Validator)
            return;

        await SaveAnnotationInner(
            message.CreatedDate,
            message.Name,
            message.ImageExtension,
            JsonConvert.DeserializeObject<List<Detection>>(message.Detections) ?? [],
            message.Source,
            new MemoryStream(message.Image),
            message.CreatedRole,
            message.CreatedEmail,
            cancellationToken);
    }

    private async Task SaveAnnotationInner(DateTime createdDate, string fName, string imageExtension, List<Detection> detections, SourceEnum source, Stream? stream,
        RoleEnum createdRole,
        string createdEmail,
        CancellationToken token = default)
    {
        //Flow for roles:
        // Operator:
        //   sourceEnum: (manual, ai) <AnnotationCreatedMessage>
        // Validator:
        //   sourceEnum: (manual)     if was in received.json then <AnnotationValidatedMessage> else <AnnotationCreatedMessage>
        //   sourceEnum: (queue, AI)  if queue CreatedMessage with the same user - do nothing Add to received.json

        var classes = detections.Select(x => x.ClassNumber).Distinct().ToList() ?? [];
        AnnotationStatus status;

        var annotation = await _dbFactory.Run(async db =>
        {
            var ann = await db.Annotations.FirstOrDefaultAsync(x => x.Name == fName, token: token);
            status = ann?.AnnotationStatus == AnnotationStatus.Created && createdRole == RoleEnum.Validator
                ? AnnotationStatus.Validated
                : AnnotationStatus.Created;

            if (ann != null)
                await db.Annotations
                    .Where(x => x.Name == fName)
                    .Set(x => x.Classes, classes)
                    .Set(x => x.Source, source)
                    .Set(x => x.AnnotationStatus, status)
                    .UpdateAsync(token: token);
            else
            {
                ann = new Annotation
                {
                    CreatedDate = createdDate,
                    Name = fName,
                    ImageExtension = imageExtension,
                    CreatedEmail = createdEmail,
                    CreatedRole = createdRole,
                    AnnotationStatus = status,
                    Source = source,
                    Detections = detections
                };
                await db.InsertAsync(ann, token: token);
            }
            return ann;
        });

        if (stream != null)
        {
            var img = System.Drawing.Image.FromStream(stream);
            img.Save(annotation.ImagePath, ImageFormat.Jpeg); //todo: check png images coming from queue
        }
        await YoloLabel.WriteToFile(detections, annotation.LabelPath, token);
        await _galleryService.CreateThumbnail(annotation, token);
        await _producer.SendToQueue(annotation, token);

        await _mediator.Publish(new AnnotationCreatedEvent(annotation), token);
    }
}