using Comal.Classes;
using InABox.Clients;
using InABox.Core;
using Syncfusion.Pdf.Graphics;
using Syncfusion.Pdf.Parsing;
using Syncfusion.Pdf;
using System;
using System.Collections.Generic;
using System.Drawing.Imaging;
using System.Drawing;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Media;
using System.Windows.Media.Imaging;
using InABox.DynamicGrid;
using InABox.WPF;
using Encoder = System.Drawing.Imaging.Encoder;
using Path = System.IO.Path;
using Image = System.Windows.Controls.Image;
using System.ComponentModel;
using System.Windows.Controls;
using Clipboard = System.Windows.Clipboard;
using DataFormats = System.Windows.DataFormats;
using DragDropEffects = System.Windows.DragDropEffects;
using DragEventArgs = System.Windows.DragEventArgs;
using MessageBox = System.Windows.MessageBox;
using UserControl = System.Windows.Controls.UserControl;
using InABox.Wpf;
using System.Collections.ObjectModel;
using System.Windows.Data;
using PRSDesktop.Panels.DataEntry;
using InABox.Wpf.Editors;
using System.Timers;
using Microsoft.Win32;
using javax.xml.crypto;

namespace PRSDesktop;

public static class PDFExtensions
{
    public static IEnumerable<PdfPageBase> GetPages(this PdfDocumentBase doc)
    {
        if (doc is PdfLoadedDocument lDoc)
            return lDoc.Pages.Cast<PdfPageBase>();
        if (doc is PdfDocument pdfDoc)
            return pdfDoc.Pages.Cast<PdfPageBase>();
        throw new Exception($"Unsupported PDF Document type {doc.GetType()}");
    }
    public static PdfPageBase GetPage(this PdfDocumentBase doc, int index)
    {
        if (doc is PdfLoadedDocument lDoc)
            return lDoc.Pages[index];
        if (doc is PdfDocument pdfDoc)
            return pdfDoc.Pages[index];
        throw new Exception($"Unsupported PDF Document type {doc.GetType()}");
    }
    public static int PageCount(this PdfDocumentBase doc)
    {
        if (doc is PdfLoadedDocument lDoc)
            return lDoc.Pages.Count;
        if (doc is PdfDocument pdfDoc)
            return pdfDoc.Pages.Count;
        throw new Exception($"Unsupported PDF Document type {doc.GetType()}");
    }
    public static PdfLoadedDocument AsLoadedDocument(this PdfDocumentBase doc)
    {
        if (doc is PdfLoadedDocument lDoc)
            return lDoc;
        if (doc is PdfDocument pdfDoc)
        {
            using var ms = new MemoryStream();
            pdfDoc.Save(ms);
            var array = ms.ToArray();
            return new PdfLoadedDocument(array);
        }
        throw new Exception($"Unsupported PDF Document type {doc.GetType()}");
    }

    public static byte[] SaveToBytes(this PdfDocumentBase doc)
    {
        using var ms = new MemoryStream();
        doc.Save(ms);
        return ms.ToArray();
    }
}

/// <summary>
/// Interaction logic for ScanPanel.xaml
/// </summary>
public partial class DataEntryList : UserControl, ICorePanel, IDockPanel
{
    private List<DataEntryDocument> SelectedScans = new();

    public delegate void DateEntrySelectionHandler(String appliesTo, Guid entityID, bool allowprocess);

    public event DateEntrySelectionHandler? SelectionChanged;

    private readonly object _viewListLock = new object();

    private class ViewDocument
    {
        public ImageSource Image { get; set; }

        public DataEntryDocument Document { get; set; }

        public int PageNumber { get; set; }

        public ViewDocument(ImageSource image, DataEntryDocument document, int page)
        {
            Image = image;
            Document = document;
            PageNumber = page;
        }
    }

    private List<ViewDocument> ViewDocuments { get; } = new();
    public ObservableCollection<ImageSource> ViewList { get; init; } = new();

    private List<DataEntryDocumentWindow> OpenWindows = new();
    
    public DataEntryList()
    {
        BindingOperations.EnableCollectionSynchronization(ViewList, _viewListLock);

        InitializeComponent();
    }

    #region Panel

    public void Setup()
    {
        _dataEntryGrid.HiddenColumns.Add(x => x.Document.ID);
        _dataEntryGrid.Refresh(true, false);
        _historyGrid.Refresh(true, false);
    }

    public void Refresh()
    {
        if (_pages.SelectedIndex == 0)
            _dataEntryGrid.Refresh(false, true);
        else if (_pages.SelectedIndex == 1)
            _historyGrid.Refresh(false,true);
            
    }

    public void Shutdown(CancelEventArgs? cancel)
    {
        CloseImageWindows();
    }

    #endregion

    #region View List

    private static List<byte[]> RenderTextFile(string textData)
    {
        var pdfDocument = new PdfDocument();
        var page = pdfDocument.Pages.Add();

        var font = new PdfStandardFont(PdfFontFamily.Courier, 14);
        var textElement = new PdfTextElement(textData, font);
        var layoutFormat = new PdfLayoutFormat
        {
            Layout = PdfLayoutType.Paginate,
            Break = PdfLayoutBreakType.FitPage
        };

        textElement.Draw(page, new RectangleF(0, 0, page.GetClientSize().Width, page.GetClientSize().Height), layoutFormat);

        using var docStream = new MemoryStream();
        pdfDocument.Save(docStream);

        var loadeddoc = new PdfLoadedDocument(docStream.ToArray());
        Bitmap[] bmpImages = loadeddoc.ExportAsImage(0, loadeddoc.Pages.Count - 1);

        var jpgEncoder = ImageUtils.GetEncoder(ImageFormat.Jpeg)!;
        var quality = Encoder.Quality;
        var encodeParams = new EncoderParameters(1);
        encodeParams.Param[0] = new EncoderParameter(quality, 100L);

        var images = new List<byte[]>();
        if (bmpImages != null)
            foreach (var image in bmpImages)
            {
                using var data = new MemoryStream();
                image.Save(data, jpgEncoder, encodeParams);
                images.Add(data.ToArray());
            }
        return images;
    }

    private void UpdateViewList(bool force = false)
    {
        var selected = _dataEntryGrid.SelectedRows.Select(x => x.ToObject<DataEntryDocument>()).ToList();
        if (!force && selected.Count == SelectedScans.Count && !selected.Any(x => SelectedScans.All(y => x.ID != y.ID)))
            return;

        SelectedScans = selected;
        ViewList.Clear();
        ViewDocuments.Clear();

        Task.Run(() =>
        {
            var docs = DataEntryCache.Cache.LoadDocuments(SelectedScans.Select(x => x.Document.ID).Distinct(), checkTimestamp: true);
            LoadDocuments(docs);
        }).ContinueWith((task) =>
        {
            if(task.Exception is not null)
            {
                MessageWindow.ShowError("An error occurred while loading the documents", task.Exception);
            }
        }, TaskScheduler.FromCurrentSynchronizationContext());
    }

    private void LoadDocuments(IEnumerable<Document> documents)
    {
        var bitmaps = new Dictionary<Guid, List<ImageSource>>();
        foreach (var document in documents)
        {
            List<byte[]> images;
            var bitmapImages = new List<ImageSource>();
            var extension = Path.GetExtension(document.FileName).ToLower();
            if (extension == ".pdf")
            {
                images = new List<byte[]>();
                try
                {
                    bitmapImages = ImageUtils.RenderPDFToImageSources(document.Data);
                }
                catch (Exception e)
                {
                    MessageBox.Show($"Cannot load document '{document.FileName}': {e.Message}");
                }
            }
            else if (extension == ".jpg" || extension == ".jpeg" || extension == ".png" || extension == ".bmp")
            {
                images = new List<byte[]> { document.Data };
            }
            else
            {
                images = ImageUtils.RenderTextFileToImages(Encoding.UTF8.GetString(document.Data));
            }

            bitmapImages.AddRange(images.Select(x =>
            {
                try
                {
                    return ImageUtils.LoadImage(x);
                }
                catch (Exception e)
                {
                    Dispatcher.BeginInvoke(() =>
                    {
                        MessageWindow.ShowError($"Cannot load document '{document.FileName}", e);
                    });
                }
                return null;
            }).Where(x => x != null).Cast<ImageSource>());

            foreach (var image in bitmapImages)
            {
                if (!bitmaps.TryGetValue(document.ID, out var list))
                {
                    list = new List<ImageSource>();
                    bitmaps[document.ID] = list;
                }

                list.Add(image);
            }
        }
        ViewDocuments.Clear();

        var maxWidth = 0.0;
        foreach (var scan in SelectedScans)
        {
            if (bitmaps.TryGetValue(scan.Document.ID, out var list))
            {
                int page = 1;
                foreach (var bitmap in list)
                {
                    maxWidth = Math.Max(maxWidth, bitmap.Width);
                    ViewDocuments.Add(new(bitmap, scan, page));
                    page++;
                }
            }
        }

        lock (_viewListLock)
        {
            ViewList.Clear();
            foreach(var doc in ViewDocuments)
            {
                ViewList.Add(doc.Image);
            }
            if(maxWidth != 0.0)
            {
                ZoomPanel.Scale = ZoomPanel.ActualWidth / (maxWidth * 1.1);
                ZoomPanel.MinScale = ZoomPanel.Scale / 2;
            }
        }
    }

    #endregion

    #region Uploading

    private static byte[] RenderData(ref string filename, byte[] data)
    {
        var extension = Path.GetExtension(filename).ToLower();
        if ((extension == ".jpg" || extension == ".jpeg" || extension == ".png" || extension == ".bmp") && ImageUtils.TryGetImageType(data, out var format))
        {
            return data;
        }
        else if (extension == ".pdf")
        {
            return data;
        }
        else
        {
            using var stream = new MemoryStream(data);
            filename = Path.ChangeExtension(filename, "pdf");
            return DataEntryReGroupWindow.RenderToPDF(filename, stream).SaveToBytes();
        }
        throw new Exception("Could not render file to PDF");
    }

    private void DynamicTabItem_Drop(object sender, DragEventArgs e)
    {
        Task.Run(() =>
        {
            Dispatcher.Invoke(() =>
            {
                Progress.Show("Uploading documents");
                try
                {
                    var result = DocumentUtils.HandleFileDrop(e);
                    if (result is not null)
                    {
                        foreach (var (filename, stream) in result)
                        {
                            var newFilename = filename;
                            byte[] data;
                            if (stream is null)
                            {
                                data = File.ReadAllBytes(newFilename);
                            }
                            else
                            {
                                using var memStream = new MemoryStream();
                                stream.CopyTo(memStream);
                                data = memStream.ToArray();
                            }
                            data = RenderData(ref newFilename, data);

                            _dataEntryGrid.UploadDocument(newFilename, data, Guid.Empty);
                        }
                    }
                    Progress.Close();
                }
                catch (Exception e)
                {
                    Progress.Close();
                    MessageWindow.ShowError("Could not upload documents.", e);
                }
            });
        });
    }

    private void DynamicTabItem_DragOver(object sender, DragEventArgs e)
    {
        if (e.Data.GetDataPresent(DataFormats.FileDrop) || e.Data.GetDataPresent("FileGroupDescriptor"))
        {
            e.Effects = DragDropEffects.Copy;
        }
        else
        {
            e.Effects = DragDropEffects.None;
        }
        e.Handled = true;
    }

    #endregion

    private void _documents_OnSelectItem(object sender, DynamicGridSelectionEventArgs e)
    {
        UpdateViewList(false);

        DoSelect(e.Rows);
    }

    private void DoSelect(CoreRow[]? rows)
    {
        var appliesTo = rows?.Length == 1
            ? rows[0].Get<DataEntryDocument, string>(x => x.Tag.AppliesTo)
            : "";
        var entityid = rows?.Length == 1
            ? rows[0].Get<DataEntryDocument, Guid>(x => x.EntityID)
            : Guid.Empty;
        var archived = rows?.Length == 1
            ? rows[0].Get<DataEntryDocument, DateTime>(x => x.Archived)
            : DateTime.MinValue;
        SelectionChanged?.Invoke(appliesTo, entityid, archived.IsEmpty());

        CloseImageWindows();
    }

    private void _historyGrid_OnOnSelectItem(object sender, DynamicGridSelectionEventArgs e)
    {
        DoSelect(e.Rows);
    }

    private void CloseImageWindows()
    {
        while (OpenWindows.Count > 0)
        {
            var win = OpenWindows.Last();
            OpenWindows.RemoveAt(OpenWindows.Count - 1);
            win.Close();
        }
    }
    private void OpenImageWindow(ImageSource image)
    {
        var window = OpenWindows.FirstOrDefault(x => x.Images.Contains(image));
        if (window is not null)
        {
            window.Activate();
        }
        else
        {
            window = new DataEntryDocumentWindow();
            window.Topmost = true;
            window.Images.Add(image);
            OpenWindows.Add(window);
            window.Closed += OpenWindow_Closed;
            window.Show();
        }
    }

    private void Image_MouseLeftButtonDown(object sender, System.Windows.Input.MouseButtonEventArgs e)
    {
        if (sender is not Image image) return;

        if(e.ClickCount >= 2)
        {
            OpenImageWindow(image.Source);
            e.Handled = true;
        }
    }

    private void OpenWindow_Closed(object? sender, EventArgs e)
    {
        if (sender is not DataEntryDocumentWindow window) return;
        OpenWindows.Remove(window);
    }

    private void _Explode_OnClick(object sender, RoutedEventArgs e)
    {
       _dataEntryGrid.DoExplode();
    }

    private List<DataEntryTag>? _tags;

    private void _uploadMenu_OnOpened(object sender, RoutedEventArgs e)
    {
        if (Clipboard.ContainsText())
        {
            _pasteItem.Header = "Paste Text from Clipboard";
            _pasteItem.Visibility = Visibility.Visible;
        }
        else if (Clipboard.ContainsImage())
        {
            _pasteItem.Header = "Paste Image from Clipboard";
            _pasteItem.Visibility = Visibility.Visible;
        }
        else if (Clipboard.ContainsFileDropList())
        {
            int count = CheckAllowableFiles();
            if (count > 0)
            {
                _pasteItem.Header = $@"Paste {count} File{(count > 1 ? "s" : "")} from Clipboard";
                _pasteItem.Visibility = Visibility.Visible;
            }
        }
        else
            _pasteItem.Visibility = Visibility.Collapsed;
        
        _archive.Visibility = _dataEntryGrid.SelectedRows.Any() && Security.CanEdit<DataEntryDocument>()
            ? Visibility.Visible
            : Visibility.Collapsed;

        _archiveseparator.Visibility = _archive.Visibility;
        
        _tags ??= DataEntryGrid.GetVisibleTagList();
        _changeTag.Items.Clear();

        foreach (var tag in _tags)
            _changeTag.Items.Add(new MenuItem()
            {
                Header = tag.Name, 
                Command = new Command((_) => ChangeTag(tag)) { }
            });
        _changeTag.Items.Add(new Separator());
        _changeTag.Items.Add(new MenuItem()
        {
            Header= "Clear Tags",
            Command = new Command((_) => ChangeTag(new DataEntryTag()))
        });
        
        _changeTag.Visibility = _dataEntryGrid.SelectedRows.Any() && _tags.Any() && (Security.CanEdit<DataEntryDocument>() || Security.IsAllowed<CanSetupDataEntryTags>())
            ? Visibility.Visible
            : Visibility.Collapsed;
        _changeNote.Visibility = _dataEntryGrid.SelectedRows.Any() && Security.CanEdit<DataEntryDocument>()
            ? Visibility.Visible
            : Visibility.Collapsed;
        
        _changetagseparator.Visibility = _archive.Visibility;
        
    }

    private void ChangeTag(object obj)
    {
        if (obj is DataEntryTag tag)
            _dataEntryGrid.DoChangeTags(tag.ID);
    }

    private void _addItem_OnClick(object sender, RoutedEventArgs e)
    {
        var ofd = new OpenFileDialog()
        {
            Filter = @"All Files (*.pdf, *.bmp, *.png, *.jpg, *.jpeg)|*.pdf;*.bmp;*.png;*.jpg;*.jpeg",
            Multiselect = true,
            Title = @"Select Files to Upload",
            InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.MyDocuments)
        };
        if (ofd.ShowDialog() == true)
        {
            foreach (var file in ofd.FileNames)
                Upload(
                    Path.GetFileName(file),
                    new FileStream(file,FileMode.Open));
        }
    }

    private void _pasteItem_OnClick(object sender, RoutedEventArgs e)
    {
        if (Clipboard.ContainsText())
        {
            Upload(
                $"Pasted Text {DateTime.Now:yyyy-MM-dd hh-mm-ss-fff}.txt",
                new MemoryStream(new UTF8Encoding().GetBytes(Clipboard.GetText()))
            );
        }
        else if (Clipboard.ContainsImage())
        {
            var img = Clipboard.GetImage();
            if (img != null)
            {
                var bmp = ImageUtils.BitmapSourceToBitmap(img);
                using (var ms = new MemoryStream())
                {
                    bmp.Save(ms, ImageFormat.Png);
                    Upload(
                        $"Pasted Image {DateTime.Now:yyyy-MM-dd hh-mm-ss-fff}.png",
                        ms
                    );
                }
            }
            
        }
        else if (CheckAllowableFiles() > 0)
        {
            var files = Clipboard.GetFileDropList().OfType<String>().ToArray();
            foreach (var file in files)
            {
                Upload(
                    Path.GetFileName(file), 
                    new FileStream(file,FileMode.Open)
                );
            }
        }
    }

    private void Upload(string filename, Stream data)
    {
        var doc = DataEntryReGroupWindow.RenderToPDF(filename, data);
        _dataEntryGrid.UploadDocument(Path.ChangeExtension(filename,"pdf"), doc.SaveToBytes(), Guid.Empty);
    }
    
    private static int CheckAllowableFiles()
    {
        var extensions = Clipboard.GetFileDropList().OfType<String>().Select(x => Path.GetExtension(x.ToUpper())).ToArray();
        return extensions.Count(x => 
            String.Equals(x, "PDF")
            || String.Equals(x, "PNG")
            || String.Equals(x, "JPG")
            || String.Equals(x, "JPEG")
            || String.Equals(x, "BMP")
            || String.Equals(x, "TXT")
        );
    }
    
    private void _pages_OnSelectionChanged(object sender, SelectionChangedEventArgs e)
    {
        if (_pages.SelectedIndex == 0)
            _dataEntryGrid.Refresh(false,true);
        else if (_pages.SelectedIndex == 1)
            _historyGrid.Refresh(false,true);
    }

    private void _remove_OnClick(object sender, RoutedEventArgs e)
    {
        _dataEntryGrid.DoRemove();
    }

    private void _reopen_OnClick(object sender, RoutedEventArgs e)
    {
        _historyGrid.DoReopen();
    }

    private void _changeNote_Click(object sender, RoutedEventArgs e)
    {
        var notes = _dataEntryGrid.SelectedRows.ToObjects<DataEntryDocument>().Select(x => x.Note).Distinct().ToArray();

        var note = notes.Length == 1 ? notes[0] : "";

        if(TextBoxDialog.Execute("Enter note:", ref note))
        {
            _dataEntryGrid.DoChangeNote(note);
        }
    }

    private void _dataEntryGrid_OnContextMenuOpening(object sender, ContextMenuEventArgs e)
    {

    }

    private void _ShowImage_Click(object sender, RoutedEventArgs e)
    {
        if (sender is not MenuItem item || item.Tag is not ImageSource image) return;

        OpenImageWindow(image);
    }

    private void RotateDocument(Document doc, int pageNumber)
    {
        var extension = Path.GetExtension(doc.FileName).ToLower();
        if (extension == ".pdf")
        {
            var loadeddoc = new PdfLoadedDocument(doc.Data);

            bool allPages = loadeddoc.PageCount() > 1;
            if (allPages)
            {
                allPages = MessageWindow.New()
                    .Message("Do you want to rotate all pages in this PDF?")
                    .Title("Rotate all?")
                    .AddYesButton("All pages")
                    .AddNoButton("Just this page")
                    .Display().Result == MessageWindowResult.Yes;
            }

            if(allPages)
            {
                foreach (var page in loadeddoc.GetPages())
                {
                    var rotation = (int)page.Rotation;
                    rotation = (rotation + 1) % 4;
                    page.Rotation = (PdfPageRotateAngle)rotation;
                }
            }
            else if(pageNumber <= loadeddoc.PageCount())
            {
                var page = loadeddoc.GetPage(pageNumber - 1);

                var rotation = (int)page.Rotation;
                rotation = (rotation + 1) % 4;
                page.Rotation = (PdfPageRotateAngle)rotation;
            }

            doc.Data = loadeddoc.SaveToBytes();
        }
        else if (extension == ".jpg" || extension == ".jpeg" || extension == ".png" || extension == ".bmp")
        {
            using var stream = new MemoryStream(doc.Data);
            var bitmap = Bitmap.FromStream(stream);
            bitmap.RotateFlip(RotateFlipType.Rotate90FlipNone);
            using var outStream = new MemoryStream();
            bitmap.Save(outStream, extension switch
            {
                ".jpg" or ".jpeg" => ImageFormat.Jpeg,
                ".png" => ImageFormat.Png,
                _ => ImageFormat.Bmp
            });
            doc.Data = outStream.ToArray();
        }
        else
        {
            using var stream = new MemoryStream(doc.Data);
            var loadeddoc = DataEntryReGroupWindow.RenderToPDF(doc.FileName, stream);

            foreach (var page in loadeddoc.GetPages())
            {
                var rotation = (int)page.Rotation;
                rotation = (rotation + 1) % 4;
                page.Rotation = (PdfPageRotateAngle)rotation;
            }

            doc.Data = loadeddoc.SaveToBytes();
        }
    }

    private void _RotateImage_Click(object sender, RoutedEventArgs e)
    {
        if (sender is not MenuItem item || item.Tag is not ImageSource image) return;

        var document = ViewDocuments.FirstOrDefault(x => x.Image == image);
        if (document is null)
        {
            MessageWindow.ShowError("An error occurred", "Document does not exist in ViewDocuments list");
            return;
        }

        var doc = DataEntryCache.Cache.LoadDocuments(CoreUtils.One(document.Document.Document.ID), checkTimestamp: true).First();
        try
        {
            RotateDocument(doc, document.PageNumber);
        }
        catch(Exception err)
        {
            MessageWindow.ShowError("Something went wrong while trying to rotate this document.", err);
            return;
        }

        Client.Save(doc, "Rotated by user.");

        if (Path.GetExtension(doc.FileName) == ".pdf")
        {
            document.Document.Thumbnail = ImageUtils.GetPDFThumbnail(doc.Data, 256, 256);
        }

        new Client<DataEntryDocument>().Save(document.Document, "");

        DataEntryCache.Cache.Add(new DataEntryCachedDocument(doc));

        UpdateViewList(true);
    }
}