using System;
using System.Text.Json;
using System.Threading.Tasks;
using Avalonia.Collections;
using Avalonia.Controls.Notifications;
using Avalonia.Platform.Storage;
using CommunityToolkit.Mvvm.ComponentModel;
using CommunityToolkit.Mvvm.Input;
using FluentAvalonia.UI.Controls;
using NLog;
using StabilityMatrix.Avalonia.Models;
using StabilityMatrix.Avalonia.Models.Inference;
using StabilityMatrix.Avalonia.Services;
using StabilityMatrix.Avalonia.ViewModels.Inference;
using StabilityMatrix.Avalonia.Views;
using StabilityMatrix.Core.Api;
using StabilityMatrix.Core.Attributes;
using StabilityMatrix.Core.Models;
using StabilityMatrix.Core.Models.FileInterfaces;
using StabilityMatrix.Core.Models.Progress;
using StabilityMatrix.Core.Services;
using Symbol = FluentIcons.Common.Symbol;
using SymbolIconSource = FluentIcons.FluentAvalonia.SymbolIconSource;

namespace StabilityMatrix.Avalonia.ViewModels;

[View(typeof(InferencePage))]
public partial class InferenceViewModel : PageViewModelBase
{
    private static readonly Logger Logger = LogManager.GetCurrentClassLogger();
    private readonly INotificationService notificationService;
    private readonly ISettingsManager settingsManager;
    private readonly ServiceManager<ViewModelBase> vmFactory;
    private readonly IApiFactory apiFactory;

    public override string Title => "Inference";
    public override IconSource IconSource =>
        new SymbolIconSource { Symbol = Symbol.AppGeneric, IsFilled = true };

    public RefreshBadgeViewModel ConnectionBadge { get; } = new()
    {
        State = ProgressState.Failed,
        FailToolTipText = "Not connected",
        FailIcon = FluentAvalonia.UI.Controls.Symbol.Refresh,
        SuccessToolTipText = "Connected",
    };
    
    public IInferenceClientManager ClientManager { get; }

    public AvaloniaList<ViewModelBase> Tabs { get; } = new();

    [ObservableProperty]
    private ViewModelBase? selectedTab;

    public InferenceViewModel(
        ServiceManager<ViewModelBase> vmFactory,
        IApiFactory apiFactory,
        INotificationService notificationService,
        IInferenceClientManager inferenceClientManager, 
        ISettingsManager settingsManager)
    {
        this.vmFactory = vmFactory;
        this.apiFactory = apiFactory;
        this.notificationService = notificationService;
        this.settingsManager = settingsManager;
        
        ClientManager = inferenceClientManager;
    }

    private InferenceTextToImageViewModel CreateTextToImageViewModel()
    {
        return vmFactory.Get<InferenceTextToImageViewModel>(vm =>
        {
            vm.Parent = this;
        });
    }

    public override void OnLoaded()
    {
        if (Tabs.Count == 0)
        {
            Tabs.Add(CreateTextToImageViewModel());
        }

        // Select first tab if none is selected
        if (SelectedTab is null && Tabs.Count > 0)
        {
            SelectedTab = Tabs[0];
        }

        base.OnLoaded();
    }

    /// <summary>
    /// When the + button on the tab control is clicked, add a new tab.
    /// </summary>
    [RelayCommand]
    private void AddTab()
    {
        Tabs.Add(CreateTextToImageViewModel());
    }
    
    /// <summary>
    /// When the close button on the tab is clicked, remove the tab.
    /// </summary>
    public void OnTabCloseRequested(TabViewTabCloseRequestedEventArgs e)
    {
        if (e.Item is ViewModelBase vm)
        {
            Tabs.Remove(vm);
        }
    }

    /// <summary>
    /// Connect to the inference server.
    /// </summary>
    [RelayCommand]
    private async Task Connect()
    {
        if (ClientManager.IsConnected)
        {
            notificationService.Show("Already connected", "ComfyUI backend is already connected");
            return;
        }
        // TODO: make address configurable

        await notificationService.TryAsync(ClientManager.ConnectAsync(),
            "Could not connect to ComfyUI backend");
    }

    /// <summary>
    /// Disconnect from the inference server.
    /// </summary>
    [RelayCommand]
    private async Task Disconnect()
    {
        if (!ClientManager.IsConnected)
        {
            notificationService.Show("Not connected", "ComfyUI backend is not connected");
            return;
        }

        await notificationService.TryAsync(ClientManager.CloseAsync(),
            "Could not disconnect from ComfyUI backend");
    }

    /// <summary>
    /// Menu "Save As" command.
    /// </summary>
    [RelayCommand]
    private async Task MenuSaveAs()
    {
        var currentTab = SelectedTab;
        if (currentTab == null)
        {
            Logger.Trace("MenuSaveAs: currentTab is null");
            return;
        }
        
        var document = InferenceProjectDocument.FromLoadable(currentTab);
        
        // Prompt for save file dialog
        var provider = App.StorageProvider;

        var projectDir = new DirectoryPath(settingsManager.LibraryDir, "Projects");
        projectDir.Create();
        var startDir = await provider.TryGetFolderFromPathAsync(projectDir);
        
        var result = await provider.SaveFilePickerAsync(new FilePickerSaveOptions
        {
            Title = "Save As",
            SuggestedFileName = "Untitled",
            FileTypeChoices = new FilePickerFileType[]
            {
                new("StabilityMatrix Project")
                {
                    Patterns = new[] { "*.smproj" },
                    MimeTypes = new[] { "application/json" },
                }
            },
            SuggestedStartLocation = startDir,
            DefaultExtension = ".smproj",
            ShowOverwritePrompt = true,
        });
        
        if (result is null)
        {
            Logger.Trace("MenuSaveAs: user cancelled");
            return;
        }
        
        // Save to file
        await using var stream = await result.OpenWriteAsync();
        await JsonSerializer.SerializeAsync(stream, document, new JsonSerializerOptions
        {
            WriteIndented = true,
        });
        
        notificationService.Show("Saved", $"Saved project to {result.Name}", NotificationType.Success);
    }

    /// <summary>
    /// Menu "Open Project" command.
    /// </summary>
    [RelayCommand]
    private async Task MenuOpenProject()
    {
        // Prompt for open file dialog
        var provider = App.StorageProvider;

        var projectDir = new DirectoryPath(settingsManager.LibraryDir, "Projects");
        projectDir.Create();
        var startDir = await provider.TryGetFolderFromPathAsync(projectDir);
        
        var results = await provider.OpenFilePickerAsync(new FilePickerOpenOptions
        {
            Title = "Open Project File",
            FileTypeFilter = new FilePickerFileType[]
            {
                new("StabilityMatrix Project")
                {
                    Patterns = new[] { "*.smproj" },
                    MimeTypes = new[] { "application/json" },
                }
            },
            SuggestedStartLocation = startDir,
        });
        
        if (results.Count == 0)
        {
            Logger.Trace("MenuOpenProject: No files selected");
            return;
        }
        
        // Load from file
        var file = results[0];
        await using var stream = await file.OpenReadAsync();
        
        var document = await JsonSerializer.DeserializeAsync<InferenceProjectDocument>(stream);
        if (document == null)
        {
            Logger.Warn("MenuOpenProject: Deserialize project file returned null");
            return;
        }

        ViewModelBase? vm = null;
        if (document.ProjectType is InferenceProjectType.TextToImage)
        {
            var textToImage = CreateTextToImageViewModel();
            textToImage.LoadState(document.State.Deserialize<InferenceTextToImageModel>()!);
            vm = textToImage;
        }
        
        if (vm == null)
        {
            Logger.Warn("MenuOpenProject: Unknown project type");
            return;
        }
        
        Tabs.Add(vm);
    }
}