PDFOffice_Windows_exe/PDF Office/ViewModels/PropertyPanel/AnnotPanel/SignatureCreateDialogViewModel.cs

using ComPDFKitViewer.PdfViewer;
using Microsoft.Win32;
using PDF_Office.Model;
using Prism.Commands;
using Prism.Mvvm;
using Prism.Regions;
using Prism.Services.Dialogs;
using System;
using System.Collections.Generic;
using System.Collections.ObjectModel;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Windows.Media;
using System.Windows.Media.Imaging;

namespace PDF_Office.ViewModels.PropertyPanel.AnnotPanel
{
    class SignatureCreateDialogViewModel : BindableBase, IDialogAware
    {
        public string Title => "";
        private CPDFViewer PDFViewer;
        public event Action<IDialogResult> RequestClose;
        public DelegateCommand CancelCommand { get; set; }

        public DelegateCommand CreateCommnad { get; set; }

        public DelegateCommand<object> CheckedCommnad { get; set; }

        public DelegateCommand OpenImageCommnad { get; set; }
        public ObservableCollection<string> FontNameList { get; set; }

        private int fontNameIndex = 0;

        public int FontNameIndex
        {
            get { return fontNameIndex; }
            set
            {
                SetProperty(ref fontNameIndex, value);
            }
        }

        private int radioButtonIndex;

        public int RadioButtonIndex
        {
            get { return radioButtonIndex; }
            set
            {
                SetProperty(ref radioButtonIndex, value);
            }
        }

        private int tabItemIndex;

        public int TabItemIndex
        {
            get { return tabItemIndex; }
            set
            {
                SetProperty(ref tabItemIndex, value);
            }
        }

        private string inputText = "";

        public string InputText
        {
            get { return inputText; }
            set
            {
                SetProperty(ref inputText, value);
            }
        }
        public string SaveToPath { get; private set; }

        public SignatureCreateDialogViewModel()
        {
            FontNameList = new ObservableCollection<string>();
            CancelCommand = new DelegateCommand(Cancel);
            CreateCommnad = new DelegateCommand(Create);
            CheckedCommnad = new DelegateCommand<object>(Checked);
            OpenImageCommnad = new DelegateCommand(OpenImage);
            InitFontNameList();
        }

        private void InitFontNameList()
        {
            System.Drawing.Text.InstalledFontCollection objFont = new System.Drawing.Text.InstalledFontCollection();
            foreach (var item in objFont.Families)
            {
                FontNameList.Add(item.Name);
            }
        }

        private void Checked(object index)
        {
            RadioButtonIndex = Convert.ToInt32(index);
        }
        public void OpenImage()
        {
            OpenFileDialog openFile = new OpenFileDialog();
            openFile.Filter = "All Image Files(*.bmp;*.gif;*.jpeg;*.jpg;*.png;*.tiff)|*.bmp;*.gif;*.jpeg;*.jpg;*.png;*.tiff|(*.bmp)|*.bmp|" +
                "(*.gif)|*.gif|" +
                "(*.jpeg)|*.jpeg|" +
                "(*.jpg)|*.jpg|" +
                "(*.png)|*.png|" +
                "(*.tiff)|*.tiff";
            if (openFile.ShowDialog() == false)
            {
                return;
            }
            string path = App.CachePath.CustomStampPath;
            string name = Guid.NewGuid().ToString();
            if (!string.IsNullOrEmpty(path))
            {
                BitmapImage image = new BitmapImage(new Uri(openFile.FileName));
                double scale = Math.Min((double)600 / image.PixelWidth, (double)600 / image.PixelHeight);
                scale = Math.Min(scale, 1);
                string ext = Path.GetExtension(openFile.FileName);
                if (ext.ToUpper() == ".PNG")
                {
                    BitmapEncoder encoder = new PngBitmapEncoder();
                    var targetBitmap = new TransformedBitmap(image, new ScaleTransform(scale, scale));
                    encoder.Frames.Add(BitmapFrame.Create(targetBitmap));
                    path = System.IO.Path.Combine(path, name);
                    using (FileStream stream = new FileStream(path, FileMode.Create))
                    {
                        encoder.Save(stream);
                    }
                    if (!string.IsNullOrEmpty(SaveToPath))
                    {
                        App.CachePath.AddToDeleteFiles(SaveToPath);
                    }
                    SaveToPath = path;
                }
                else
                {
                    BitmapEncoder encoder = new JpegBitmapEncoder();
                    TransformedBitmap targetBitmap = new TransformedBitmap(image, new ScaleTransform(scale, scale));
                    encoder.Frames.Add(BitmapFrame.Create(targetBitmap));
                    path = System.IO.Path.Combine(path, name);
                    using (FileStream stream = new FileStream(path, FileMode.Create))
                    {
                        encoder.Save(stream);
                    }
                    if (!string.IsNullOrEmpty(SaveToPath))
                    {
                        App.CachePath.AddToDeleteFiles(SaveToPath);
                    }
                    SaveToPath = path;
                }
            }
            else
            {
                SaveToPath = "";
            }
        }

        /// <summary>
        /// 把文字转换成Bitmap
        /// </summary>
        /// <param name="text"></param>
        /// <param name="font"></param>
        /// <param name="rect">用于输出的矩形，文字在这个矩形内显示，为空时自动计算</param>
        /// <param name="fontcolor">字体颜色</param>
        /// <param name="backColor">背景颜色</param>
        /// <returns></returns>
        private Bitmap TextToBitmap(string text, Font font, Rectangle rect, System.Drawing.Color fontcolor, System.Drawing.Color backColor)
        {
            Graphics g;
            Bitmap bmp;
            StringFormat format = new StringFormat(StringFormatFlags.NoClip);
            if (rect == Rectangle.Empty)
            {
                bmp = new Bitmap(1, 1);
                g = Graphics.FromImage(bmp);
                //计算绘制文字所需的区域大小（根据宽度计算长度），重新创建矩形区域绘图
                SizeF sizef = g.MeasureString(text, font, PointF.Empty, format);

                int width = (int)(sizef.Width + 1);
                int height = (int)(sizef.Height + 1);
                rect = new Rectangle(0, 0, width, height);
                bmp.Dispose();

                bmp = new Bitmap(width, height);
            }
            else
            {
                bmp = new Bitmap(rect.Width, rect.Height);
            }

            g = Graphics.FromImage(bmp);

            //使用ClearType字体功能
            g.TextRenderingHint = System.Drawing.Text.TextRenderingHint.AntiAlias;
            g.FillRectangle(new SolidBrush(backColor), rect);
            g.DrawString(text, font, new SolidBrush(fontcolor), rect, format);
            return bmp;
        }
        private void Cancel()
        {
            RequestClose.Invoke(new DialogResult(ButtonResult.Cancel));
        }

        private void Create()
        {
            switch (TabItemIndex)
            {
                case 0:
                    Bitmap bmp = TextToBitmap(InputText, new Font(FontNameList[fontNameIndex], 48), Rectangle.Empty, System.Drawing.Color.Red, System.Drawing.Color.Transparent);
                    string guid = Guid.NewGuid().ToString();
                    string path = System.IO.Path.Combine(App.CachePath.SignatureStampPath, guid);
                    bmp.Save(path, ImageFormat.Png);
                    SaveToPath = path;
                    break;
                case 1:
                    break;
                case 2:
                    break;
                default:
                    break;
            }
            DialogParameters valuePairs = new DialogParameters();
            valuePairs.Add(ParameterNames.DataModel, this);
            RequestClose.Invoke(new DialogResult(ButtonResult.OK, valuePairs));
        }

        public bool CanCloseDialog()
        {
            return true;
        }

        public void OnDialogClosed()
        {
            return;
        }

        public void OnDialogOpened(IDialogParameters parameters)
        {
            if (parameters != null)
            {
                PDFViewer = parameters.GetValue<CPDFViewer>(ParameterNames.PDFViewer);
                if (PDFViewer != null)
                {

                }
            }
            return;
        }
    }
}