using System;
using System.Collections.Generic;
using System.Collections.Immutable;
using System.ComponentModel.DataAnnotations;
using System.IO;
using System.Linq;
using System.Text.Json.Serialization;
using System.Threading;
using System.Threading.Tasks;
using AsyncAwaitBestPractices;
using Avalonia.Media.Imaging;
using Avalonia.Threading;
using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using NLog;
using Refit;
using SkiaSharp;
using StabilityMatrix.Avalonia.Helpers;
using StabilityMatrix.Avalonia.Models;
using StabilityMatrix.Avalonia.Services;
using StabilityMatrix.Avalonia.ViewModels.Base;
using StabilityMatrix.Avalonia.Views;
using StabilityMatrix.Core.Attributes;
using StabilityMatrix.Core.Extensions;
using StabilityMatrix.Core.Helper;
using StabilityMatrix.Core.Inference;
using StabilityMatrix.Core.Models;
using StabilityMatrix.Core.Models.Api.Comfy;
using StabilityMatrix.Core.Models.Api.Comfy.Nodes;
using StabilityMatrix.Core.Models.Api.Comfy.NodeTypes;
using StabilityMatrix.Core.Models.Api.Comfy.WebSocketData;
using StabilityMatrix.Core.Services;
using InferenceTextToImageView = StabilityMatrix.Avalonia.Views.Inference.InferenceTextToImageView;

#pragma warning disable CS0657 // Not a valid attribute location for this declaration

namespace StabilityMatrix.Avalonia.ViewModels.Inference;

[View(typeof(InferenceTextToImageView), persistent: true)]
public partial class InferenceTextToImageViewModel : InferenceTabViewModelBase
{
    private static readonly Logger Logger = LogManager.GetCurrentClassLogger();

    private readonly INotificationService notificationService;
    private readonly ServiceManager<ViewModelBase> vmFactory;
    private readonly IModelIndexService modelIndexService;

    public IInferenceClientManager ClientManager { get; }

    public ImageGalleryCardViewModel ImageGalleryCardViewModel { get; }
    public PromptCardViewModel PromptCardViewModel { get; }
    public StackCardViewModel StackCardViewModel { get; }

    public UpscalerCardViewModel UpscalerCardViewModel =>
        StackCardViewModel.GetCard<StackExpanderViewModel>().GetCard<UpscalerCardViewModel>();

    public SamplerCardViewModel HiresSamplerCardViewModel =>
        StackCardViewModel.GetCard<StackExpanderViewModel>().GetCard<SamplerCardViewModel>();

    public bool IsHiresFixEnabled => StackCardViewModel.GetCard<StackExpanderViewModel>().IsEnabled;

    public bool IsUpscaleEnabled => StackCardViewModel.GetCard<StackExpanderViewModel>(1).IsEnabled;

    [JsonIgnore]
    public ProgressViewModel OutputProgress { get; } = new();

    [ObservableProperty]
    [property: JsonIgnore]
    private string? outputImageSource;

    public InferenceTextToImageViewModel(
        INotificationService notificationService,
        IInferenceClientManager inferenceClientManager,
        ServiceManager<ViewModelBase> vmFactory,
        IModelIndexService modelIndexService
    )
    {
        this.notificationService = notificationService;
        this.vmFactory = vmFactory;
        this.modelIndexService = modelIndexService;
        ClientManager = inferenceClientManager;

        // Get sub view models from service manager

        var seedCard = vmFactory.Get<SeedCardViewModel>();
        seedCard.GenerateNewSeed();

        ImageGalleryCardViewModel = vmFactory.Get<ImageGalleryCardViewModel>();
        PromptCardViewModel = vmFactory.Get<PromptCardViewModel>();

        StackCardViewModel = vmFactory.Get<StackCardViewModel>();

        StackCardViewModel.AddCards(
            new LoadableViewModelBase[]
            {
                // Model Card
                vmFactory.Get<ModelCardViewModel>(),
                // Sampler
                vmFactory.Get<SamplerCardViewModel>(samplerCard =>
                {
                    samplerCard.IsDimensionsEnabled = true;
                    samplerCard.IsCfgScaleEnabled = true;
                    samplerCard.IsSamplerSelectionEnabled = true;
                    samplerCard.IsSchedulerSelectionEnabled = true;
                }),
                // Hires Fix
                vmFactory.Get<StackExpanderViewModel>(stackExpander =>
                {
                    stackExpander.Title = "Hires Fix";
                    stackExpander.AddCards(
                        new LoadableViewModelBase[]
                        {
                            // Hires Fix Upscaler
                            vmFactory.Get<UpscalerCardViewModel>(),
                            // Hires Fix Sampler
                            vmFactory.Get<SamplerCardViewModel>(samplerCard =>
                            {
                                samplerCard.IsDenoiseStrengthEnabled = true;
                            })
                        }
                    );
                }),
                vmFactory.Get<StackExpanderViewModel>(stackExpander =>
                {
                    stackExpander.Title = "Upscale";
                    stackExpander.AddCards(
                        new LoadableViewModelBase[]
                        {
                            // Post processing upscaler
                            vmFactory.Get<UpscalerCardViewModel>(),
                        }
                    );
                }),
                // Seed
                seedCard,
                // Batch Size
                vmFactory.Get<BatchSizeCardViewModel>(),
            }
        );

        // GenerateImageCommand.WithNotificationErrorHandler(notificationService);
    }

    private (NodeDictionary prompt, string[] outputs) BuildPrompt(
        GenerateOverrides? overrides = null
    )
    {
        using var _ = new CodeTimer();

        var samplerCard = StackCardViewModel.GetCard<SamplerCardViewModel>();
        var batchCard = StackCardViewModel.GetCard<BatchSizeCardViewModel>();
        var modelCard = StackCardViewModel.GetCard<ModelCardViewModel>();
        var seedCard = StackCardViewModel.GetCard<SeedCardViewModel>();

        var nodes = new NodeDictionary();
        var builder = new ComfyNodeBuilder(nodes);

        var emptyLatentImage = nodes.AddNamedNode(
            new NamedComfyNode("EmptyLatentImage")
            {
                ClassType = "EmptyLatentImage",
                Inputs = new Dictionary<string, object?>
                {
                    ["batch_size"] = batchCard.BatchSize,
                    ["height"] = samplerCard.Height,
                    ["width"] = samplerCard.Width,
                }
            }
        );

        var checkpointLoader = nodes.AddNamedNode(
            new NamedComfyNode("CheckpointLoader")
            {
                ClassType = "CheckpointLoaderSimple",
                Inputs = new Dictionary<string, object?>
                {
                    ["ckpt_name"] = modelCard.SelectedModelName
                }
            }
        );

        // Global connections for chaining
        var modelSource = checkpointLoader.GetOutput<ModelNodeConnection>(0);
        var clipSource = checkpointLoader.GetOutput<ClipNodeConnection>(1);
        var vaeSource = checkpointLoader.GetOutput<VAENodeConnection>(2);

        // Use custom VAE if enabled
        if (modelCard is { IsVaeSelectionEnabled: true, SelectedVae.IsDefault: false })
        {
            // Add a loader
            var vaeLoader = nodes.AddNamedNode(
                ComfyNodeBuilder.VAELoader("VAELoader", modelCard.SelectedVae.FileName)
            );

            // Set as source
            vaeSource = vaeLoader.Output;
        }

        // See if we need to load loras
        var prompt = PromptCardViewModel.GetPrompt();
        prompt.Process();
        var negativePrompt = PromptCardViewModel.GetNegativePrompt();
        negativePrompt.Process();

        // If need to load loras, add a group
        if (prompt.ExtraNetworks.Count > 0)
        {
            // Convert to local file names
            var loras = prompt.ExtraNetworks.Select(n =>
            {
                var localLoras = modelIndexService.ModelIndex.GetOrAdd(SharedFolderType.Lora);
                var localLora = localLoras.FirstOrDefault(
                    m =>
                        m.FileName == n.Name
                        || Path.GetFileNameWithoutExtension(m.FileName) == n.Name
                );

                if (localLora is null)
                {
                    throw new ApplicationException($"Lora model {n.Name} was not found locally");
                }

                return (localLora.FileName, n.ModelWeight, n.ClipWeight);
            });

            var lorasGroup = builder.Group_LoraLoadMany("Loras", modelSource, clipSource, loras);

            // Set as source
            modelSource = lorasGroup.Output1;
            clipSource = lorasGroup.Output2;
        }

        var positiveClip = nodes.AddNamedNode(
            new NamedComfyNode("PositiveCLIP")
            {
                ClassType = "CLIPTextEncode",
                Inputs = new Dictionary<string, object?>
                {
                    ["clip"] = clipSource,
                    ["text"] = prompt.ProcessedText,
                }
            }
        );

        var negativeClip = nodes.AddNamedNode(
            new NamedComfyNode("NegativeCLIP")
            {
                ClassType = "CLIPTextEncode",
                Inputs = new Dictionary<string, object?>
                {
                    ["clip"] = clipSource,
                    ["text"] = negativePrompt.ProcessedText,
                }
            }
        );

        var sampler = nodes.AddNamedNode(
            ComfyNodeBuilder.KSampler(
                "Sampler",
                modelSource,
                Convert.ToUInt64(seedCard.Seed),
                samplerCard.Steps,
                samplerCard.CfgScale,
                samplerCard.SelectedSampler
                    ?? throw new ValidationException("Sampler not selected"),
                samplerCard.SelectedScheduler
                    ?? throw new ValidationException("Sampler not selected"),
                positiveClip.GetOutput<ConditioningNodeConnection>(0),
                negativeClip.GetOutput<ConditioningNodeConnection>(0),
                emptyLatentImage.GetOutput<LatentNodeConnection>(0),
                samplerCard.DenoiseStrength
            )
        );

        var lastLatent = sampler.Output;
        var lastLatentWidth = samplerCard.Width;
        var lastLatentHeight = samplerCard.Height;

        var vaeDecoder = nodes.AddNamedNode(
            new NamedComfyNode("VAEDecoder")
            {
                ClassType = "VAEDecode",
                Inputs = new Dictionary<string, object?>
                {
                    ["samples"] = lastLatent,
                    ["vae"] = vaeSource
                }
            }
        );

        var saveImage = nodes.AddNamedNode(
            new NamedComfyNode("SaveImage")
            {
                ClassType = "SaveImage",
                Inputs = new Dictionary<string, object?>
                {
                    ["filename_prefix"] = "SM-Inference",
                    ["images"] = vaeDecoder.GetOutput(0)
                }
            }
        );

        // If hi-res fix is enabled, add the LatentUpscale node and another KSampler node
        if (overrides?.IsHiresFixEnabled ?? IsHiresFixEnabled)
        {
            var hiresUpscalerCard = UpscalerCardViewModel;
            var hiresSamplerCard = HiresSamplerCardViewModel;

            // Requested upscale to this size
            var hiresWidth = (int)Math.Floor(lastLatentWidth * hiresUpscalerCard.Scale);
            var hiresHeight = (int)Math.Floor(lastLatentHeight * hiresUpscalerCard.Scale);

            LatentNodeConnection hiresLatent;

            // Select between latent upscale and normal upscale based on the upscale method
            var selectedUpscaler = hiresUpscalerCard.SelectedUpscaler!.Value;

            if (selectedUpscaler.Type == ComfyUpscalerType.None)
            {
                // If no upscaler selected or none, just reroute the latent image
                hiresLatent = sampler.Output;
            }
            else
            {
                // Otherwise upscale the latent image
                hiresLatent = builder
                    .Group_UpscaleToLatent(
                        "HiresFix",
                        lastLatent,
                        vaeSource,
                        selectedUpscaler,
                        hiresWidth,
                        hiresHeight
                    )
                    .Output;
            }

            var hiresSampler = nodes.AddNamedNode(
                ComfyNodeBuilder.KSampler(
                    "HiresSampler",
                    modelSource,
                    Convert.ToUInt64(seedCard.Seed),
                    hiresSamplerCard.Steps,
                    hiresSamplerCard.CfgScale,
                    // Use hires sampler name if not null, otherwise use the normal sampler
                    hiresSamplerCard.SelectedSampler
                        ?? samplerCard.SelectedSampler
                        ?? throw new ValidationException("Sampler not selected"),
                    hiresSamplerCard.SelectedScheduler
                        ?? samplerCard.SelectedScheduler
                        ?? throw new ValidationException("Scheduler not selected"),
                    positiveClip.GetOutput<ConditioningNodeConnection>(0),
                    negativeClip.GetOutput<ConditioningNodeConnection>(0),
                    hiresLatent,
                    hiresSamplerCard.DenoiseStrength
                )
            );

            // Set as last latent
            lastLatent = hiresSampler.Output;
            lastLatentWidth = hiresWidth;
            lastLatentHeight = hiresHeight;
            // Reroute the VAEDecoder's input to be from the hires sampler
            vaeDecoder.Inputs["samples"] = lastLatent;
        }

        // If upscale is enabled, add another upscale group
        if (IsUpscaleEnabled)
        {
            var postUpscalerCard = StackCardViewModel
                .GetCard<StackExpanderViewModel>(1)
                .GetCard<UpscalerCardViewModel>();

            var upscaleWidth = (int)Math.Floor(lastLatentWidth * postUpscalerCard.Scale);
            var upscaleHeight = (int)Math.Floor(lastLatentHeight * postUpscalerCard.Scale);

            // Build group
            var postUpscaleGroup = builder.Group_UpscaleToImage(
                "PostUpscale",
                lastLatent,
                vaeSource,
                postUpscalerCard.SelectedUpscaler!.Value,
                upscaleWidth,
                upscaleHeight
            );

            // Remove the original vae decoder
            nodes.Remove(vaeDecoder.Name);

            // Set as the input for save image
            saveImage.Inputs["images"] = postUpscaleGroup.Output;
        }

        nodes.NormalizeConnectionTypes();

        return (nodes, new[] { saveImage.Name });
    }

    private void OnProgressUpdateReceived(object? sender, ComfyProgressUpdateEventArgs args)
    {
        Dispatcher.UIThread.Post(() =>
        {
            OutputProgress.Value = args.Value;
            OutputProgress.Maximum = args.Maximum;
            OutputProgress.IsIndeterminate = false;

            OutputProgress.Text =
                $"({args.Value} / {args.Maximum})"
                + (args.RunningNode != null ? $" {args.RunningNode}" : "");
        });
    }

    private void OnPreviewImageReceived(object? sender, ComfyWebSocketImageData args)
    {
        ImageGalleryCardViewModel.SetPreviewImage(args.ImageBytes);
    }

    private async Task GenerateImageImpl(
        GenerateOverrides? overrides = null,
        CancellationToken cancellationToken = default
    )
    {
        if (!ClientManager.IsConnected)
        {
            notificationService.Show("Client not connected", "Please connect first");
            return;
        }

        // Validate the prompts
        if (!await PromptCardViewModel.ValidatePrompts())
        {
            return;
        }

        // If enabled, randomize the seed
        var seedCard = StackCardViewModel.GetCard<SeedCardViewModel>();
        if (overrides is not { UseCurrentSeed: true } && seedCard.IsRandomizeEnabled)
        {
            seedCard.GenerateNewSeed();
        }

        var client = ClientManager.Client;

        var (nodes, outputNodeNames) = BuildPrompt(overrides);

        // Connect preview image handler
        client.PreviewImageReceived += OnPreviewImageReceived;

        ComfyTask? promptTask = null;
        try
        {
            // Register to interrupt if user cancels
            cancellationToken.Register(() =>
            {
                Logger.Info("Cancelling prompt");
                client
                    .InterruptPromptAsync(new CancellationTokenSource(5000).Token)
                    .SafeFireAndForget();
            });

            try
            {
                promptTask = await client.QueuePromptAsync(nodes, cancellationToken);
            }
            catch (ApiException e)
            {
                Logger.Warn(e, "Api exception while queuing prompt");
                await DialogHelper.CreateApiExceptionDialog(e, "Api Error").ShowAsync();
                return;
            }

            // Register progress handler
            promptTask.ProgressUpdate += OnProgressUpdateReceived;

            // Wait for prompt to finish
            await promptTask.Task.WaitAsync(cancellationToken);
            Logger.Trace($"Prompt task {promptTask.Id} finished");

            // Get output images
            var imageOutputs = await client.GetImagesForExecutedPromptAsync(
                promptTask.Id,
                cancellationToken
            );

            ImageGalleryCardViewModel.ImageSources.Clear();

            var images = imageOutputs[outputNodeNames[0]];
            if (images is null)
                return;

            List<ImageSource> outputImages;
            // Use local file path if available, otherwise use remote URL
            if (client.OutputImagesDir is { } outputPath)
            {
                outputImages = images
                    .Select(i => new ImageSource(i.ToFilePath(outputPath)))
                    .ToList();
            }
            else
            {
                outputImages = images
                    .Select(i => new ImageSource(i.ToUri(client.BaseAddress)))
                    .ToList();
            }

            // Download all images to make grid, if multiple
            if (outputImages.Count > 1)
            {
                var loadedImages = outputImages
                    .Select(i => SKImage.FromEncodedData(i.LocalFile?.Info.OpenRead()))
                    .ToImmutableArray();

                var grid = ImageProcessor.CreateImageGrid(loadedImages);

                // Save to disk
                var lastName = outputImages.Last().LocalFile?.Info.Name;
                var gridPath = client.OutputImagesDir!.JoinFile($"grid-{lastName}");

                await using (var fileStream = gridPath.Info.OpenWrite())
                {
                    await fileStream.WriteAsync(grid.Encode().ToArray(), cancellationToken);
                }

                // Insert to start of images
                var gridImage = new ImageSource(gridPath);
                // Preload
                await gridImage.GetBitmapAsync();
                ImageGalleryCardViewModel.ImageSources.Add(gridImage);
            }

            // Add rest of images
            foreach (var img in outputImages)
            {
                // Preload
                await img.GetBitmapAsync();
                ImageGalleryCardViewModel.ImageSources.Add(img);
            }
        }
        finally
        {
            // Disconnect progress handler
            OutputProgress.Value = 0;
            OutputProgress.Text = "";
            ImageGalleryCardViewModel.PreviewImage?.Dispose();
            ImageGalleryCardViewModel.PreviewImage = null;
            ImageGalleryCardViewModel.IsPreviewOverlayEnabled = false;

            promptTask?.Dispose();
            client.PreviewImageReceived -= OnPreviewImageReceived;
        }
    }

    [RelayCommand(IncludeCancelCommand = true)]
    private async Task GenerateImage(
        string? options = null,
        CancellationToken cancellationToken = default
    )
    {
        try
        {
            var overrides = new GenerateOverrides
            {
                IsHiresFixEnabled = options?.Contains("hires_fix"),
                UseCurrentSeed = options?.Contains("current_seed")
            };

            await GenerateImageImpl(overrides, cancellationToken);
        }
        catch (OperationCanceledException e)
        {
            Logger.Debug($"[Image Generation Canceled] {e.Message}");
        }
    }

    internal class GenerateOverrides
    {
        public bool? IsHiresFixEnabled { get; set; }
        public bool? UseCurrentSeed { get; set; }
    }
}