fix: added edge-case handling for images with zero available height (#377)

Author: philprime

Example iOS-SwiftPM/Example_iOS-SPM.xcodeproj/project.pbxproj

@@ -523,7 +523,7 @@
 				GCC_WARN_UNUSED_LABEL = YES;
 				GCC_WARN_UNUSED_PARAMETER = YES;
 				INFOPLIST_FILE = Example/Info.plist;
-				IPHONEOS_DEPLOYMENT_TARGET = 12;
+				IPHONEOS_DEPLOYMENT_TARGET = 16;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",
@@ -548,7 +548,7 @@
 				GCC_WARN_UNUSED_LABEL = YES;
 				GCC_WARN_UNUSED_PARAMETER = YES;
 				INFOPLIST_FILE = Example/Info.plist;
-				IPHONEOS_DEPLOYMENT_TARGET = 12;
+				IPHONEOS_DEPLOYMENT_TARGET = 16;
 				LD_RUNPATH_SEARCH_PATHS = (
 					"$(inherited)",
 					"@executable_path/Frameworks",

Shared/Examples/ExperimentFactory.swift

@@ -8,43 +8,37 @@
 
 import Foundation
 import TPPDF
+import UIKit
 
 class ExperimentFactory: ExampleFactory {
     func generateDocument() -> [PDFDocument] {
-        let document = PDFDocument(format: .a4)
-
-        let items = (0..<40).map { $0.description }
-
-        // Simple bullet point list
-        let featureList = PDFList(indentations: [
-            (pre: 10.0, past: 20.0),
-            (pre: 20.0, past: 20.0),
-            (pre: 40.0, past: 20.0),
-        ])
-
-        // By adding the item first to a list item with the dot symbol, all of them will inherit it
-        featureList
-            .addItem(PDFListItem(symbol: .dot)
-                .addItems(items.map { item in
-                    PDFListItem(content: item)
-                }))
-        document.add(list: featureList)
-
-        document.add(space: 20)
-
-        // Numbered list with unusual indentation
-        let weirdIndentationList = PDFList(indentations: [
-            (pre: 10.0, past: 20.0),
-            (pre: 40.0, past: 30.0),
-            (pre: 20.0, past: 50.0),
-        ])
-
-        weirdIndentationList
-            .addItems(items.enumerated().map { arg in
-                PDFListItem(symbol: .numbered(value: "\(arg.offset + 1)"), content: arg.element)
-            })
-        document.add(list: weirdIndentationList)
-
+        let document = PDFDocument(format: .b5)
+        document.add(.contentCenter, text: "Some Test Name")
+        let images = [
+            "file:///Users/Philip/Downloads/test_images/0000.jpg",
+            "file:///Users/Philip/Downloads/test_images/0001.jpg",
+            "file:///Users/Philip/Downloads/test_images/0002.jpg",
+            "file:///Users/Philip/Downloads/test_images/0003.jpg",
+            "file:///Users/Philip/Downloads/test_images/0004.jpg",
+            "file:///Users/Philip/Downloads/test_images/0005.jpg",
+            "file:///Users/Philip/Downloads/test_images/0006.jpg",
+            "file:///Users/Philip/Downloads/test_images/0007.jpg",
+            "file:///Users/Philip/Downloads/test_images/0008.jpg",
+            "file:///Users/Philip/Downloads/test_images/0009.jpg",
+        ]
+        images[0..<images.count].compactMap({ imageFileUrl -> PDFImage? in
+            guard let imageURL = URL(string: imageFileUrl),
+                  let image = UIImage(contentsOfFile: imageURL.path(percentEncoded: false)),
+                  image.size != .zero
+            else {
+                return nil
+            }
+
+            let pdfImage = PDFImage(image: image)
+            return pdfImage
+        }).forEach({ pdfImage in
+            document.add(image: pdfImage)
+        })
         return [document]
     }
 }

Source/Internal/Image/PDFImageObject.swift

@@ -56,7 +56,10 @@ class PDFImageObject: PDFRenderObject {
                                                                                  sizeFit: image.sizeFit)
         let availableSize = PDFCalculations.calculateAvailableFrame(for: generator, in: container)
         if container.isCenter {
-            if imageSize.height + captionSize.height > availableSize.height || (image.sizeFit == .height && imageSize.height < image.size.height) {
+            let isAvailableHeightZero = availableSize.height == 0
+            let isImageCaptionHeightCombinedTooSmall = imageSize.height + captionSize.height > availableSize.height
+            let isImageHeightTooSmall = image.sizeFit == .height && imageSize.height < image.size.height
+            if isAvailableHeightZero || isImageCaptionHeightCombinedTooSmall || isImageHeightTooSmall {
                 result += try PDFPageBreakObject().calculate(generator: generator, container: container)
                 generator.layout.heights.content = 0