PDFOffice_Windows_exe/PDF Office/ViewModels/EditTools/Background/BackgroundDocumentContentViewModel.cs

using ComPDFKit.PDFDocument;
using ComPDFKit.PDFPage;
using ComPDFKitViewer.PdfViewer;
using PDF_Office.EventAggregators;
using PDF_Office.Helper;
using PDF_Office.Model;
using PDF_Office.Model.EditTools.Background;
using Prism.Commands;
using Prism.Events;
using Prism.Mvvm;
using Prism.Regions;
using System;
using System.Collections.Generic;
using System.Drawing;
using System.Linq;
using System.Threading.Tasks;
using System.Windows;
using System.Windows.Media;
using System.Windows.Media.Imaging;

namespace PDF_Office.ViewModels.EditTools.Background
{
    public class BackgroundDocumentContentViewModel : BindableBase,INavigationAware
    {
        public IEventAggregator eventAggregator;
        public CPDFViewer PDFViewer;
        public CPDFDocument document;
        public CPDFBackground background;


        private ImageSource _imageSource = null;
        public ImageSource ImageSource
        {
            get { return _imageSource; }
            set
            {
                SetProperty(ref _imageSource, value);
            }
        }


        public BackgroundDocumentContentViewModel(IEventAggregator  eventAggregator)
        {
            this.eventAggregator = eventAggregator;
            eventAggregator.GetEvent<SetBackgroundEvent>().Subscribe(SetBackground);
        }

        public async void AwaitRenderBitmap(CPDFDocument doc)
        {
            await RenderBitmap(doc);
        }

        public void SetBackground( BackgroundInfo backgroundInfo)
        {
            CreateBackground(backgroundInfo);
            document.PdfToImage("0-1", "D:\\");
            document.WriteToFilePath("D:\\sb22222.pdf");
            AwaitRenderBitmap(document);
        }

        public void CreateBackground(BackgroundInfo backgroundInfo)
        {
            byte[] color = {0,255, 255};
            background = document.GetBackground();
            backgroundInfo.BackgroundType = C_Background_Type.BG_TYPE_IMAGE;

            if (backgroundInfo.BackgroundType == C_Background_Type.BG_TYPE_COLOR)
            {
                background.SetBackgroundType(C_Background_Type.BG_TYPE_COLOR);
                background.SetColor(color);
                background.SetScale(1);
            }
            else
            {
                background.SetBackgroundType(C_Background_Type.BG_TYPE_IMAGE);
                background.SetImage(backgroundInfo.ImageArray, backgroundInfo.ImageWidth, backgroundInfo.ImageHeight, ComPDFKit.Import.C_Scale_Type.fitCenter);
                background.SetScale(1);
            }
            background.SetHorizalign(C_Background_Horizalign.BG_HORIZALIGN_CENTER);
            background.SetVertalign(C_Background_Vertalign.BG_VERTALIGN_CENTER);
            background.SetOpacity(50);
            background.SetPages("0");
            background.SetRotation(0);
            background.SetXOffset(0);
            background.SetYOffset(0);
            background.Update();
            background.Release();
        }

        public static BitmapSource ToBitmapSource(System.Drawing.Bitmap image)
        {
            IntPtr ptr = image.GetHbitmap();//obtain the Hbitmap
            BitmapSource bs = System.Windows.Interop.Imaging.CreateBitmapSourceFromHBitmap
            (
                ptr,
                IntPtr.Zero,
                Int32Rect.Empty,
                System.Windows.Media.Imaging.BitmapSizeOptions.FromEmptyOptions()
            );
            return bs;
        }


        public async Task RenderBitmap(CPDFDocument doc)
        {

            CPDFPage page = doc.PageAtIndex(0, true);

            byte[] bmp_data = new byte[(int)page.PageSize.Width * (int)page.PageSize.Height * 4];
            Bitmap bitmap = await ToolMethod.RenderPageBitmap(document, (int)(page.PageSize.Width * 1.4), (int)(page.PageSize.Height * 1.4), 0, true, true);
            //await Task.Run(delegate
            //{
            //    page.RenderPageBitmap(0, 0, (int)page.PageSize.Width, (int)page.PageSize.Height, 0xffffffff, bmp_data, 1);
            //});
            //PixelFormat fmt = PixelFormats.Bgra32;
            //BitmapSource bps = BitmapSource.Create((int)page.PageSize.Width, (int)page.PageSize.Height, 96.0, 96.0, fmt, null, bmp_data, ((int)page.PageSize.Width * fmt.BitsPerPixel + 7) / 8);
            ImageSource = ToBitmapSource(bitmap);
            doc.ReleasePages();
        }

        public bool IsNavigationTarget(NavigationContext navigationContext)
        {
            return true;
        }

        public void OnNavigatedFrom(NavigationContext navigationContext)
        {
        }

        public void OnNavigatedTo(NavigationContext navigationContext)
        {
            navigationContext.Parameters.TryGetValue<CPDFViewer>(ParameterNames.PDFViewer, out PDFViewer);
            document = PDFViewer.Document;
            AwaitRenderBitmap(PDFViewer.Document);
        }
    }
}