Add WeasyPrint to convert PDFs

Elwig/Documents/Pdf.cs

@@ -1,64 +1,45 @@
-using System;
 using System.Threading.Tasks;
-using System.Windows;
-using PdfSharp.Pdf.IO;
-using PuppeteerSharp;
 using Elwig.Helpers;
 using Elwig.Windows;
 using System.Diagnostics;
+using Balbarak.WeasyPrint;
+using System;
+using System.IO;
 
 namespace Elwig.Documents {
     public static class Pdf {
 
-        private static readonly string Chromium = @"C:\Program Files (x86)\Microsoft\Edge\Application\msedge.exe";
         private static readonly string PdfToPrinter = App.ExePath + "PDFtoPrinter.exe";
-        private static IBrowser? Browser = null;
-        public static bool IsReady => Browser != null;
+        private static readonly FilesManager WeasyPrintManager = new();
+        private static string? WeasyPrintPython = null;
+        private static string? WeasyPrintDir => WeasyPrintManager.FolderPath;
+        public static bool IsReady => WeasyPrintPython != null && WeasyPrintDir != null;
 
         public static async Task Init(Action evtHandler) {
-            Browser = await Puppeteer.LaunchAsync(new LaunchOptions {
-                Headless = true,
-                ExecutablePath = Chromium,
-                // paged.js uses XHRs to load styles, so this is needed
-                Args = new[] { "--allow-file-access-from-files" },
-            });
+            if (!WeasyPrintManager.IsFilesExsited()) {
+                await WeasyPrintManager.InitFilesAsync();
+            }
+            WeasyPrintPython = Path.Combine(WeasyPrintManager.FolderPath, "python.exe");
             evtHandler();
         }
 
-        public static async Task Close() {
-            if (Browser == null) return;
-            await Browser.CloseAsync();
-            Browser = null;
-        }
-
         public static async Task Convert(string htmlPath, string pdfPath) {
-            if (Browser == null) throw new InvalidOperationException("The puppeteer engine has not been initialized yet");
-            using var page = await Browser.NewPageAsync();
-            page.Console += OnConsole;
-            await page.GoToAsync($"file://{htmlPath}");
-            await page.EvaluateFunctionAsync("async () => { await window.PagedPolyfill.preview(); }");
-            await page.PdfAsync(pdfPath, new() {
-                PreferCSSPageSize = true,
-                //Format = PaperFormat.A4,
-                DisplayHeaderFooter = false,
-                MarginOptions = new() {
-                    Top = "0mm",
-                    Right = "0mm",
-                    Bottom = "0mm",
-                    Left = "0mm",
-                },
-            });
-        }
-
-        private static void OnConsole(object? sender, ConsoleEventArgs e) {
-            MessageBox.Show(e.Message.Text);
-        }
-
-        public static void UpdateMetadata(string path, string title, string author) {
-            using var doc = PdfReader.Open(path);
-            doc.Info.Title = title;
-            doc.Info.Author = author;
-            doc.Save(path);
+            var p = new Process() { StartInfo = new() {
+                FileName = WeasyPrintPython,
+                CreateNoWindow = true,
+                WorkingDirectory = WeasyPrintDir,
+                RedirectStandardError = true,
+            } };
+            p.StartInfo.EnvironmentVariables["PATH"] = "Scripts;gtk3;" + Environment.GetEnvironmentVariable("PATH");
+            p.StartInfo.ArgumentList.Add("scripts/weasyprint.exe");
+            p.StartInfo.ArgumentList.Add("-e");
+            p.StartInfo.ArgumentList.Add("utf8");
+            p.StartInfo.ArgumentList.Add(htmlPath);
+            p.StartInfo.ArgumentList.Add(pdfPath);
+            p.Start();
+            await p.WaitForExitAsync();
+            var stderr = await p.StandardError.ReadToEndAsync();
+            if (p.ExitCode != 0) throw new Exception(stderr);
         }
 
         public static void Show(TempFile file, string title) {