using Avalonia;
using Avalonia.Controls;
using Avalonia.Interactivity;
using Avalonia.Layout;
using Avalonia.Platform.Storage;
using Avalonia.Styling;
using Avalonia.Threading;
using ImageCatalog_2.Services;
using Microsoft.Extensions.DependencyInjection;
using System.ComponentModel;
using System.IO;

namespace ImageCatalog_2;

public partial class AvaloniaMainWindow : Window
{
    private readonly DataModel _model;
    private readonly PickerPreferenceService _pickerPreferenceService;
    private bool _isDarkTheme;
    private bool _startupSettingsRestoreAttempted;

    public AvaloniaMainWindow()
        : this(Program.ServiceProvider.GetRequiredService<DataModel>())
    {
    }

    public AvaloniaMainWindow(DataModel model)
    {
        InitializeComponent();

        _model = model;
        _pickerPreferenceService = Program.ServiceProvider.GetRequiredService<PickerPreferenceService>();
        DataContext = _model;

        Opened += async (_, _) =>
        {
            SyncThemeStateFromCurrentTheme();
            await TryLoadLastSettingsOnStartupAsync();
        };
        Closing += AvaloniaMainWindow_Closing;

        // Let DataModel marshal callbacks onto Avalonia UI thread.
        _model.UiInvoker = action => Dispatcher.UIThread.Invoke(action);
        _model.ConfirmAiCsvOverwriteAsync = ShowConfirmationDialogAsync;

        _model.SelectSourceFolderRequested += async (_, _) =>
        {
            var suggestedStartLocation = await _pickerPreferenceService.TryGetStartFolderAsync(StorageProvider, PickerPreferenceKeys.SourceFolder, _model.SourcePath);
            var folders = await StorageProvider.OpenFolderPickerAsync(new FolderPickerOpenOptions
            {
                Title = "Seleziona cartella sorgente",
                SuggestedStartLocation = suggestedStartLocation
            });

            if (folders.Count > 0)
            {
                _model.SourcePath = folders[0].Path.LocalPath + Path.DirectorySeparatorChar;
                _pickerPreferenceService.RememberPath(PickerPreferenceKeys.SourceFolder, _model.SourcePath);
            }
        };

        _model.SelectDestinationFolderRequested += async (_, _) =>
        {
            var suggestedStartLocation = await _pickerPreferenceService.TryGetStartFolderAsync(StorageProvider, PickerPreferenceKeys.DestinationFolder, _model.DestinationPath);
            var folders = await StorageProvider.OpenFolderPickerAsync(new FolderPickerOpenOptions
            {
                Title = "Seleziona cartella destinazione",
                SuggestedStartLocation = suggestedStartLocation
            });

            if (folders.Count > 0)
            {
                _model.DestinationPath = folders[0].Path.LocalPath + Path.DirectorySeparatorChar;
                _pickerPreferenceService.RememberPath(PickerPreferenceKeys.DestinationFolder, _model.DestinationPath);
            }
        };

        _model.SelectLogoFileRequested += async (_, _) =>
        {
            var suggestedStartLocation = await _pickerPreferenceService.TryGetStartFolderAsync(StorageProvider, PickerPreferenceKeys.LogoFile, _model.LogoFile);
            var files = await StorageProvider.OpenFilePickerAsync(new FilePickerOpenOptions
            {
                Title = "Seleziona logo",
                SuggestedStartLocation = suggestedStartLocation,
                FileTypeFilter =
                [
                    new FilePickerFileType("Immagini") { Patterns = ["*.jpg", "*.jpeg", "*.png", "*.bmp", "*.gif"] }
                ]
            });

            if (files.Count > 0)
            {
                _model.LogoFile = files[0].Path.LocalPath;
                _pickerPreferenceService.RememberPath(PickerPreferenceKeys.LogoFile, _model.LogoFile);
            }
        };

        _model.SelectModelsFolderRequested += async (_, _) =>
        {
            var suggestedStartLocation = await _pickerPreferenceService.TryGetStartFolderAsync(StorageProvider, PickerPreferenceKeys.ModelsFolder, _model.ModelsFolderPath);
            var folders = await StorageProvider.OpenFolderPickerAsync(new FolderPickerOpenOptions
            {
                Title = "Seleziona cartella modelli",
                SuggestedStartLocation = suggestedStartLocation
            });

            if (folders.Count > 0)
            {
                _model.ModelsFolderPath = folders[0].Path.LocalPath + Path.DirectorySeparatorChar;
                _pickerPreferenceService.RememberPath(PickerPreferenceKeys.ModelsFolder, _model.ModelsFolderPath);
            }
        };

        _model.SelectCsvOutputRequested += async (_, _) =>
        {
            var suggestedStartLocation = await _pickerPreferenceService.TryGetStartFolderAsync(StorageProvider, PickerPreferenceKeys.CsvOutput, _model.CsvOutputPath);
            var file = await StorageProvider.SaveFilePickerAsync(new FilePickerSaveOptions
            {
                Title = "Salva CSV",
                DefaultExtension = "csv",
                FileTypeChoices = [new FilePickerFileType("CSV") { Patterns = ["*.csv"] }],
                SuggestedStartLocation = suggestedStartLocation
            });

            if (file is not null)
            {
                _model.CsvOutputPath = file.Path.LocalPath;
                _pickerPreferenceService.RememberPath(PickerPreferenceKeys.CsvOutput, _model.CsvOutputPath);
            }
        };

        _model.SaveSettingsRequested += async (_, _) =>
        {
            var suggestedStartLocation = await _pickerPreferenceService.TryGetStartFolderAsync(StorageProvider, PickerPreferenceKeys.SettingsFile);
            var file = await StorageProvider.SaveFilePickerAsync(new FilePickerSaveOptions
            {
                Title = "Salva impostazioni",
                DefaultExtension = "xml",
                FileTypeChoices = [new FilePickerFileType("Setup") { Patterns = ["*.xml"] }],
                SuggestedStartLocation = suggestedStartLocation
            });

            if (file is not null)
            {
                await _model.SaveSettingsToFileAsync(file.Path.LocalPath);
                _pickerPreferenceService.RememberPath(PickerPreferenceKeys.SettingsFile, file.Path.LocalPath);
                _pickerPreferenceService.RememberValue(PickerPreferenceKeys.LastSettingsFile, file.Path.LocalPath);
            }
        };

        _model.LoadSettingsRequested += async (_, _) =>
        {
            var suggestedStartLocation = await _pickerPreferenceService.TryGetStartFolderAsync(StorageProvider, PickerPreferenceKeys.SettingsFile);
            var files = await StorageProvider.OpenFilePickerAsync(new FilePickerOpenOptions
            {
                Title = "Carica impostazioni",
                FileTypeFilter = [new FilePickerFileType("Setup") { Patterns = ["*.xml"] }],
                SuggestedStartLocation = suggestedStartLocation
            });

            if (files.Count > 0)
            {
                await _model.LoadSettingsFromFileAsync(files[0].Path.LocalPath);
                _pickerPreferenceService.RememberPath(PickerPreferenceKeys.SettingsFile, files[0].Path.LocalPath);
                _pickerPreferenceService.RememberValue(PickerPreferenceKeys.LastSettingsFile, files[0].Path.LocalPath);
            }
        };

        _model.SelectColorRequested += (_, _) =>
        {
            // Color is set by typing hex directly in the TextBox.
        };

        _model.SelectTransparentColorRequested += (_, _) =>
        {
            // Color is set by typing hex directly in the TextBox.
        };

        _model.ShowMessageRequested += async (_, args) =>
        {
            await ShowMessageDialogAsync(args.Item1, args.Item2);
        };
    }

    private bool _isStoppingFaceEncoderForClose;

    private async Task TryLoadLastSettingsOnStartupAsync()
    {
        if (_startupSettingsRestoreAttempted)
        {
            return;
        }

        _startupSettingsRestoreAttempted = true;

        var lastSettingsFile = _pickerPreferenceService.GetRememberedValue(PickerPreferenceKeys.LastSettingsFile);
        if (string.IsNullOrWhiteSpace(lastSettingsFile))
        {
            return;
        }

        if (!File.Exists(lastSettingsFile))
        {
            _pickerPreferenceService.ForgetValue(PickerPreferenceKeys.LastSettingsFile);
            return;
        }

        try
        {
            await _model.LoadSettingsFromFileAsync(lastSettingsFile);
            _pickerPreferenceService.RememberPath(PickerPreferenceKeys.SettingsFile, lastSettingsFile);
        }
        catch (Exception ex)
        {
            await ShowMessageDialogAsync("Impostazioni", $"Impossibile caricare il file impostazioni automatico:\n{ex.GetBaseException().Message}");
        }
    }

    private async void AvaloniaMainWindow_Closing(object? sender, CancelEventArgs e)
    {
        if (_isStoppingFaceEncoderForClose || (!_model.IsFaceEncoderRunning && !_model.IsFaceMatcherRunning))
        {
            return;
        }

        e.Cancel = true;
        _isStoppingFaceEncoderForClose = true;

        try
        {
            if (_model.IsFaceMatcherRunning)
            {
                await _model.StopFaceMatcherAsync("Arresto face matcher in chiusura...", waitForExit: true);
            }

            if (_model.IsFaceEncoderRunning)
            {
                await _model.StopFaceEncoderAsync("Arresto face encoder in chiusura...", waitForExit: true);
            }
        }
        finally
        {
            _isStoppingFaceEncoderForClose = false;
            Close();
        }
    }

    private void ToggleTheme_Click(object? sender, RoutedEventArgs e)
    {
        _isDarkTheme = !_isDarkTheme;

        if (Avalonia.Application.Current is not null)
        {
            Avalonia.Application.Current.RequestedThemeVariant = _isDarkTheme ? ThemeVariant.Dark : ThemeVariant.Light;
        }

        UpdateThemeToggleButtonContent();
    }

    private void SyncThemeStateFromCurrentTheme()
    {
        _isDarkTheme = ActualThemeVariant == ThemeVariant.Dark;
        UpdateThemeToggleButtonContent();
    }

    private void UpdateThemeToggleButtonContent()
    {
        _ = this.FindControl<Avalonia.Controls.Button>("ThemeToggleButton");
    }

    private async Task ShowMessageDialogAsync(string title, string message)
    {
        var dialog = new Window
        {
            Title = title,
            Width = 480,
            CanResize = false,
            WindowStartupLocation = WindowStartupLocation.CenterOwner,
            SizeToContent = SizeToContent.Height
        };

        dialog.Content = BuildMessageDialogContent(message, () => dialog.Close());

        await dialog.ShowDialog(this);
    }

    private async Task<bool> ShowConfirmationDialogAsync(string title, string message)
    {
        var dialog = new Window
        {
            Title = title,
            Width = 520,
            CanResize = false,
            WindowStartupLocation = WindowStartupLocation.CenterOwner,
            SizeToContent = SizeToContent.Height
        };

        dialog.Content = BuildConfirmationDialogContent(
            message,
            () => dialog.Close(true),
            () => dialog.Close(false));

        return await dialog.ShowDialog<bool>(this);
    }

    private static Control BuildMessageDialogContent(string message, Action closeDialog)
    {
        var layout = new StackPanel
        {
            Margin = new Thickness(16),
            Spacing = 12
        };

        layout.Children.Add(new TextBlock
        {
            Text = message,
            TextWrapping = Avalonia.Media.TextWrapping.Wrap,
            MaxWidth = 420
        });

        var closeButton = new Button
        {
            Content = "OK",
            MinWidth = 88,
            HorizontalAlignment = HorizontalAlignment.Right
        };

        closeButton.Click += (_, _) => closeDialog();

        layout.Children.Add(closeButton);
        return layout;
    }

    private static Control BuildConfirmationDialogContent(string message, Action confirmDialog, Action cancelDialog)
    {
        var layout = new StackPanel
        {
            Margin = new Thickness(16),
            Spacing = 12
        };

        layout.Children.Add(new TextBlock
        {
            Text = message,
            TextWrapping = Avalonia.Media.TextWrapping.Wrap,
            MaxWidth = 460
        });

        var buttons = new StackPanel
        {
            Orientation = Orientation.Horizontal,
            HorizontalAlignment = HorizontalAlignment.Right,
            Spacing = 8
        };

        var cancelButton = new Button
        {
            Content = "Annulla",
            MinWidth = 96
        };
        cancelButton.Click += (_, _) => cancelDialog();

        var confirmButton = new Button
        {
            Content = "Sovrascrivi",
            MinWidth = 96
        };
        confirmButton.Click += (_, _) => confirmDialog();

        buttons.Children.Add(cancelButton);
        buttons.Children.Add(confirmButton);
        layout.Children.Add(buttons);
        return layout;
    }
}