Add unit tests for DocumentOperation methods

Source/QuestPDF.UnitTests/DocumentOperationTests.cs

@@ -0,0 +1,239 @@
+using System;
+using System.Linq;
+using NUnit.Framework;
+using QuestPDF.Fluent;
+using QuestPDF.Helpers;
+using QuestPDF.Infrastructure;
+
+namespace QuestPDF.UnitTests;
+
+/// <summary>
+/// This test suite focus on executing various QPDF operations.
+/// In most cases, it does not check the result but rather if any exception is thrown.
+/// </summary>
+public class DocumentOperationTests
+{
+    [Test]
+    public void TakePages()
+    {
+        GenerateSampleDocument("take-input.pdf", Colors.Red.Medium, 10);
+        
+        DocumentOperation
+            .LoadFile("take-input.pdf")
+            .TakePages("2-5")
+            .Save("operation-take.pdf");
+    }
+    
+    [Test]
+    public void MergeTest()
+    {
+        GenerateSampleDocument("merge-first.pdf", Colors.Red.Medium, 3);
+        GenerateSampleDocument("merge-second.pdf", Colors.Green.Medium, 5);
+        GenerateSampleDocument("merge-third.pdf", Colors.Blue.Medium, 7);
+        
+        DocumentOperation
+            .LoadFile("merge-first.pdf")
+            .MergeFile("merge-second.pdf")
+            .MergeFile("merge-third.pdf")
+            .Save("operation-merged.pdf");
+    }
+    
+    [Test]
+    public void OverlayTest()
+    {
+        GenerateSampleDocument("overlay-main.pdf", Colors.Red.Medium, 10);
+        GenerateSampleDocument("overlay-watermark.pdf", Colors.Green.Medium, 5);
+        
+        DocumentOperation
+            .LoadFile("overlay-main.pdf")
+            .OverlayFile(new DocumentOperation.LayerConfiguration
+            {
+                FilePath = "overlay-watermark.pdf"
+            })
+            .Save("operation-overlay.pdf");
+    }
+    
+    [Test]
+    public void UnderlayTest()
+    {
+        GenerateSampleDocument("underlay-main.pdf", Colors.Red.Medium, 10);
+        GenerateSampleDocument("underlay-watermark.pdf", Colors.Green.Medium, 5);
+        
+        DocumentOperation
+            .LoadFile("underlay-main.pdf")
+            .UnderlayFile(new DocumentOperation.LayerConfiguration
+            {
+                FilePath = "underlay-watermark.pdf",
+            })
+            .Save("operation-underlay.pdf");
+    }
+
+    [Test]
+    public void AttachmentTest()
+    {
+        GenerateSampleDocument("attachment-main.pdf", Colors.Red.Medium, 10);
+        GenerateSampleDocument("attachment-file.pdf", Colors.Green.Medium, 5);
+        
+        DocumentOperation
+            .LoadFile("attachment-main.pdf")
+            .AddAttachment(new DocumentOperation.DocumentAttachment
+            {
+                FilePath = "attachment-file.pdf"
+            })
+            .Save("operation-attachment.pdf");
+    }
+    
+    [Test]
+    public void Encrypt40Test()
+    {
+        GenerateSampleDocument("encrypt40-input.pdf", Colors.Red.Medium, 10);
+        
+        DocumentOperation
+            .LoadFile("encrypt40-input.pdf")
+            .Encrypt(new DocumentOperation.Encryption40Bit()
+            {
+                UserPassword = "user_password",
+                OwnerPassword = "owner_password"
+            })
+            .Save("operation-encrypt40.pdf");
+    }
+    
+    [Test]
+    public void Encrypt128Test()
+    {
+        GenerateSampleDocument("encrypt128-input.pdf", Colors.Red.Medium, 10);
+        
+        DocumentOperation
+            .LoadFile("encrypt128-input.pdf")
+            .Encrypt(new DocumentOperation.Encryption128Bit()
+            {
+                UserPassword = "user_password",
+                OwnerPassword = "owner_password"
+            })
+            .Save("operation-encrypt128.pdf");
+    }
+    
+    [Test]
+    public void Encrypt256Test()
+    {
+        GenerateSampleDocument("encrypt256-input.pdf", Colors.Red.Medium, 10);
+        
+        DocumentOperation
+            .LoadFile("encrypt256-input.pdf")
+            .Encrypt(new DocumentOperation.Encryption256Bit()
+            {
+                UserPassword = "user_password",
+                OwnerPassword = "owner_password"
+            })
+            .Save("operation-encrypt256.pdf");
+    }
+    
+    [Test]
+    public void LinearizeTest()
+    {
+        GenerateSampleDocument("linearize-input.pdf", Colors.Red.Medium, 10);
+        
+        DocumentOperation
+            .LoadFile("linearize-input.pdf")
+            .Linearize()
+            .Save("operation-linearize.pdf");
+    }
+    
+    [Test]
+    public void DecryptTest()
+    {
+        GenerateSampleDocument("decrypt-input-not-encrypted.pdf", Colors.Red.Medium, 10);
+        
+        DocumentOperation
+            .LoadFile("decrypt-input-not-encrypted.pdf")
+            .Encrypt(new DocumentOperation.Encryption256Bit()
+            {
+                UserPassword = "user_password",
+                OwnerPassword = "owner_password"
+            })
+            .Save("decrypt-input-encrypted.pdf");
+        
+        DocumentOperation
+            .LoadFile("decrypt-input-encrypted.pdf", "owner_password")
+            .Decrypt()
+            .Save("operation-decrypt.pdf");
+    }
+    
+    [Test]
+    public void LoadEncryptedWithIncorrectPasswordTest()
+    {
+        GenerateSampleDocument("load-encrypted-input-not-encrypted.pdf", Colors.Red.Medium, 10);
+        
+        DocumentOperation
+            .LoadFile("load-encrypted-input-not-encrypted.pdf")
+            .Encrypt(new DocumentOperation.Encryption256Bit()
+            {
+                UserPassword = "user_password",
+                OwnerPassword = "owner_password"
+            })
+            .Save("load-encrypted-input-encrypted.pdf");
+        
+        Assert.Catch(() =>
+        {
+            DocumentOperation
+                .LoadFile("load-encrypted-input-encrypted.pdf", "wrong_password")
+                .Save("operation-load-encrypted.pdf");
+        });
+    }
+    
+    [Test]
+    public void ExtendMetadataTest()
+    {
+        GenerateSampleDocument("extend-metadata-input.pdf", Colors.Red.Medium, 10);
+        
+        // requires PDF/A-3b
+        DocumentOperation
+            .LoadFile("extend-metadata-input.pdf")
+            .ExtendMetadata("<rdf:Description xmlns:dc=\"http://purl.org/dc/elements/1.1/\" rdf:about=\"\"></rdf:Description>")
+            .Save("operation-extend-metadata.pdf");
+    }
+
+    
+    private void GenerateSampleDocument(string filePath, Color color, int length)
+    {
+        Document
+            .Create(document =>
+            {
+                document.Page(page =>
+                {
+                    page.Size(PageSizes.A4);
+                    page.PageColor(Colors.Transparent);
+                    
+                    page.Content().Column(column =>
+                    {
+                        foreach (var i in Enumerable.Range(1, length))
+                        {
+                            if (i != 1)
+                                column.Item().PageBreak();
+                            
+                            var width = Random.Shared.Next(100, 200);
+                            var height = Random.Shared.Next(100, 200);
+                            
+                            var horizontalTranslation = Random.Shared.Next(0, (int)PageSizes.A4.Width - width);
+                            var verticalTranslation = Random.Shared.Next(0, (int)PageSizes.A4.Height - height);
+                            
+                            column.Item()
+                                .TranslateX(horizontalTranslation)
+                                .TranslateY(verticalTranslation)
+                                .Width(width)
+                                .Height(height)
+                                .Background(color.WithAlpha(64))
+                                .AlignCenter()
+                                .AlignMiddle()
+                                .Text($"{filePath}\npage {i}")
+                                .FontColor(color)
+                                .Bold()
+                                .FontSize(16);
+                        }
+                    });
+                });
+            })
+            .WithSettings(new DocumentSettings { PdfA = true })
+            .GeneratePdf(filePath);
+    }
+}