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Services/PdfShellService.cs

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+using System.Diagnostics;
+using System.IO;
+using CRAWLER.Models;
+
+namespace CRAWLER.Services;
+
+internal interface IPdfOpener
+{
+    void OpenAttachment(PdfAttachment attachment);
+    void OpenUri(string uri);
+}
+
+internal sealed class PdfShellService : IPdfOpener
+{
+    public void OpenAttachment(PdfAttachment attachment)
+    {
+        if (attachment == null)
+        {
+            return;
+        }
+
+        if (!string.IsNullOrWhiteSpace(attachment.LocalPath) && File.Exists(attachment.LocalPath))
+        {
+            OpenUri(attachment.LocalPath);
+            return;
+        }
+
+        if (!string.IsNullOrWhiteSpace(attachment.SourceUrl))
+        {
+            OpenUri(attachment.SourceUrl);
+        }
+    }
+
+    public void OpenUri(string uri)
+    {
+        if (string.IsNullOrWhiteSpace(uri))
+        {
+            return;
+        }
+
+        Process.Start(new ProcessStartInfo(uri)
+        {
+            UseShellExecute = true
+        });
+    }
+}