Introduce support of intrinsic aspect ratio in flex algorithm

DEVSIX-5004

Author: Eugene Bochilo

io/src/main/java/com/itextpdf/io/LogMessageConstant.java

@@ -110,6 +110,8 @@ public final class LogMessageConstant {
     public static final String FAILED_TO_PROCESS_A_TRANSFORMATION_MATRIX = "Failed to process a transformation matrix which is noninvertible. Some content may be placed not as expected.";
     public static final String FIELD_VALUE_IS_NOT_CONTAINED_IN_OPT_ARRAY = "Value \"{0}\" is not contained in /Opt array of field \"{1}\".";
     public static final String FILE_CHANNEL_CLOSING_FAILED = "Closing of the file channel this source is based on failed.";
+    public static final String FLEX_ITEM_LAYOUT_RESULT_IS_NOT_FULL =
+            "Flex item layout result isn't full, but it must be. The cross size of the flex item will be 0.";
     public static final String FLUSHED_OBJECT_CONTAINS_FREE_REFERENCE = "Flushed object contains indirect reference which is free. Null object will be written instead.";
     public static final String FLUSHED_OBJECT_CONTAINS_REFERENCE_WHICH_NOT_REFER_TO_ANY_OBJECT = "Flushed object contains indirect reference which doesn't refer to any other object. Null object will be written instead.";
     public static final String FONT_DICTIONARY_WITH_NO_FONT_DESCRIPTOR = "Font dictionary does not contain required /FontDescriptor entry.";

layout/src/main/java/com/itextpdf/layout/renderer/AbstractRenderer.java

@@ -1308,6 +1308,55 @@ protected static boolean isOverflowFit(OverflowPropertyValue rendererOverflowPro
         return rendererOverflowProperty == null || OverflowPropertyValue.FIT.equals(rendererOverflowProperty);
     }
 
+    /**
+     * Replaces given property own value with the given value.
+     *
+     * @param property the property to be replaced
+     * @param replacementValue the value with which property will be replaced
+     * @param <T> the type associated with the property
+     * @return previous property value
+     */
+    <T> T replaceOwnProperty(int property, T replacementValue) {
+        T ownProperty = this.<T>getOwnProperty(property);
+        setProperty(property, replacementValue);
+        return ownProperty;
+    }
+
+    /**
+     * Returns back own value of the given property.
+     *
+     * @param property the property to be returned back
+     * @param prevValue the value which will be returned back
+     * @param <T> the type associated with the property
+     */
+    <T> void returnBackOwnProperty(int property, T prevValue) {
+        if (prevValue == null) {
+            deleteOwnProperty(property);
+        } else {
+            setProperty(property, prevValue);
+        }
+    }
+
+    /**
+     * Checks if this renderer has intrinsic aspect ratio.
+     *
+     * @return true, if aspect ratio is defined for this renderer, false otherwise
+     */
+    boolean hasAspectRatio() {
+        // TODO DEVSIX-5255 This method should be changed after we support aspect-ratio property
+        return false;
+    }
+
+    /**
+     * Gets intrinsic aspect ratio for this renderer.
+     *
+     * @return aspect ratio, if it is defined for this renderer, null otherwise
+     */
+    Float getAspectRatio() {
+        // TODO DEVSIX-5255 This method should be changed after we support aspect-ratio property
+        return null;
+    }
+
     static void processWaitingDrawing(IRenderer child, Transform transformProp, List<IRenderer> waitingDrawing) {
         if (FloatingHelper.isRendererFloating(child) || transformProp != null) {
             waitingDrawing.add(child);

layout/src/main/java/com/itextpdf/layout/renderer/FlexUtil.java

@@ -101,6 +101,8 @@ public class ImageRenderer extends AbstractRenderer implements ILeafElementRende
      */
     public ImageRenderer(Image image) {
         super(image);
+        imageWidth = image.getImageWidth();
+        imageHeight = image.getImageHeight();
     }
 
     @Override
@@ -111,8 +113,6 @@ public LayoutResult layout(LayoutContext layoutContext) {
         AffineTransform t = new AffineTransform();
         Image modelElement = (Image) (getModelElement());
         PdfXObject xObject = modelElement.getXObject();
-        imageWidth = modelElement.getImageWidth();
-        imageHeight = modelElement.getImageHeight();
 
         calculateImageDimensions(layoutBox, t, xObject);
 
@@ -390,6 +390,40 @@ public Rectangle getBorderAreaBBox() {
         return initialOccupiedAreaBBox;
     }
 
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    boolean hasAspectRatio() {
+        return true;
+    }
+
+    /**
+     * {@inheritDoc}
+     */
+    @Override
+    Float getAspectRatio() {
+        return imageWidth / imageHeight;
+    }
+
+    /**
+     * Gets original width of the image, not the width set by {@link Image#setWidth} method.
+     *
+     * @return original image width
+     */
+    public float getImageWidth() {
+        return imageWidth;
+    }
+
+    /**
+     * Gets original height of the image, not the height set by {@link Image#setHeight} method.
+     *
+     * @return original image height
+     */
+    public float getImageHeight() {
+        return imageHeight;
+    }
+
     @Override
     protected Rectangle applyPaddings(Rectangle rect, UnitValue[] paddings, boolean reverse) {
         return rect;

layout/src/main/java/com/itextpdf/layout/renderer/ImageRenderer.java

@@ -80,14 +80,9 @@ public FlexContainerTest(Object alignItemsValue, Object justifyContentValue, Obj
     public static Iterable<Object[]> alignItemsAndJustifyContentProperties() {
         return Arrays.asList(new Object[][]{
                 {AlignmentPropertyValue.FLEX_START, JustifyContent.FLEX_START, 1},
-                {AlignmentPropertyValue.START, JustifyContent.START, 2},
-                {AlignmentPropertyValue.SELF_START, JustifyContent.SELF_START, 3},
-                {AlignmentPropertyValue.BASELINE, JustifyContent.LEFT, 4},
-                {AlignmentPropertyValue.FLEX_END, JustifyContent.FLEX_END, 5},
-                {AlignmentPropertyValue.END, JustifyContent.END, 6},
-                {AlignmentPropertyValue.SELF_END, JustifyContent.RIGHT, 7},
-                {AlignmentPropertyValue.CENTER, JustifyContent.CENTER, 8},
-                {AlignmentPropertyValue.STRETCH, JustifyContent.CENTER, 9}
+                {AlignmentPropertyValue.FLEX_END, JustifyContent.FLEX_END, 2},
+                {AlignmentPropertyValue.CENTER, JustifyContent.CENTER, 3},
+                {AlignmentPropertyValue.STRETCH, JustifyContent.CENTER, 4}
         });
     }
 

layout/src/test/java/com/itextpdf/layout/element/FlexContainerTest.java

@@ -29,6 +29,7 @@ This file is part of the iText (R) project.
 import com.itextpdf.kernel.geom.Rectangle;
 import com.itextpdf.kernel.pdf.PdfDocument;
 import com.itextpdf.kernel.pdf.PdfWriter;
+import com.itextpdf.kernel.pdf.xobject.PdfFormXObject;
 import com.itextpdf.layout.Document;
 import com.itextpdf.layout.Style;
 import com.itextpdf.layout.borders.SolidBorder;
@@ -2266,6 +2267,150 @@ public void differentBasisPercentSumGtWidthGrow1Shrink0Test01() {
         Assert.assertEquals(200f, rectangleTable.get(0).get(2).getRectangle().getWidth(), EPS);
     }
 
+    @Test
+    public void calculateMinContentWithMinWidthTest() {
+        DivRenderer divRenderer = new DivRenderer(new Div());
+        divRenderer.setProperty(Property.WIDTH, UnitValue.createPointValue(100));
+        divRenderer.setProperty(Property.MIN_WIDTH, UnitValue.createPointValue(30));
+
+        FlexUtil.FlexItemCalculationInfo info = createFlexItemCalculationInfo(divRenderer);
+        Assert.assertEquals(30f, info.minContent, EPS);
+
+        divRenderer.setProperty(Property.WIDTH, UnitValue.createPointValue(30));
+        divRenderer.setProperty(Property.MIN_WIDTH, UnitValue.createPointValue(100));
+
+        info = createFlexItemCalculationInfo(divRenderer);
+        Assert.assertEquals(100f, info.minContent, EPS);
+    }
+
+    @Test
+    public void calculateMinContentForDivWithContentTest() {
+        Div div = new Div();
+        div.add(new Div().setWidth(50));
+        IRenderer divRenderer = div.createRendererSubTree();
+
+        FlexUtil.FlexItemCalculationInfo info = createFlexItemCalculationInfo((AbstractRenderer) divRenderer);
+        Assert.assertEquals(50.0f, info.minContent, EPS);
+    }
+
+    @Test
+    public void calculateMinContentForDivWithWidthTest() {
+        DivRenderer divRenderer = new DivRenderer(new Div());
+        divRenderer.setProperty(Property.WIDTH, UnitValue.createPointValue(100));
+
+        FlexUtil.FlexItemCalculationInfo info = createFlexItemCalculationInfo(divRenderer);
+        Assert.assertEquals(0.0f, info.minContent, EPS);
+    }
+
+    @Test
+    public void calculateMinContentForDivWithWidthAndContentTest() {
+        Div div = new Div();
+        div.add(new Div().setWidth(50));
+        IRenderer divRenderer = div.createRendererSubTree();
+        divRenderer.setProperty(Property.WIDTH, UnitValue.createPointValue(100));
+
+        FlexUtil.FlexItemCalculationInfo info = createFlexItemCalculationInfo((AbstractRenderer) divRenderer);
+        Assert.assertEquals(50.0f, info.minContent, EPS);
+
+        div = new Div();
+        div.add(new Div().setWidth(150));
+        divRenderer = div.createRendererSubTree();
+        divRenderer.setProperty(Property.WIDTH, UnitValue.createPointValue(100));
+
+        info = createFlexItemCalculationInfo((AbstractRenderer) divRenderer);
+        Assert.assertEquals(100.0f, info.minContent, EPS);
+    }
+
+    @Test
+    public void calculateMinContentForDivWithWidthMaxWidthAndContentTest() {
+        Div div = new Div();
+        div.add(new Div().setWidth(50));
+        div.setProperty(Property.MAX_WIDTH, UnitValue.createPointValue(45));
+        IRenderer divRenderer = div.createRendererSubTree();
+        divRenderer.setProperty(Property.WIDTH, UnitValue.createPointValue(100));
+
+        FlexUtil.FlexItemCalculationInfo info = createFlexItemCalculationInfo((AbstractRenderer) divRenderer);
+        Assert.assertEquals(45.0f, info.minContent, EPS);
+
+        div = new Div();
+        div.add(new Div().setWidth(150));
+        div.setProperty(Property.MAX_WIDTH, UnitValue.createPointValue(120));
+        divRenderer = div.createRendererSubTree();
+        divRenderer.setProperty(Property.WIDTH, UnitValue.createPointValue(100));
+
+        info = createFlexItemCalculationInfo((AbstractRenderer) divRenderer);
+        Assert.assertEquals(100.0f, info.minContent, EPS);
+    }
+
+    @Test
+    public void calculateMinContentForImageTest() {
+        Image image = new Image(new PdfFormXObject(new Rectangle(60, 150)));
+        IRenderer imageRenderer = image.createRendererSubTree();
+
+        FlexUtil.FlexItemCalculationInfo info = createFlexItemCalculationInfo((AbstractRenderer) imageRenderer);
+        Assert.assertEquals(60.0f, info.minContent, EPS);
+    }
+
+    @Test
+    public void calculateMinContentForImageWithHeightTest() {
+        Image image = new Image(new PdfFormXObject(new Rectangle(60, 150)));
+        image.setHeight(300);
+        IRenderer imageRenderer = image.createRendererSubTree();
+
+        FlexUtil.FlexItemCalculationInfo info = createFlexItemCalculationInfo((AbstractRenderer) imageRenderer);
+        Assert.assertEquals(60.0f, info.minContent, EPS);
+
+        image = new Image(new PdfFormXObject(new Rectangle(60, 150)));
+        image.setHeight(100);
+        imageRenderer = image.createRendererSubTree();
+
+        info = createFlexItemCalculationInfo((AbstractRenderer) imageRenderer);
+        Assert.assertEquals(40.0f, info.minContent, EPS);
+    }
+
+    @Test
+    public void calculateMinContentForImageWithHeightAndMinMaxHeightsTest() {
+        Image image = new Image(new PdfFormXObject(new Rectangle(60, 150)));
+        image.setHeight(300);
+        image.setMinHeight(20);
+        image.setMaxHeight(100);
+        IRenderer imageRenderer = image.createRendererSubTree();
+
+        FlexUtil.FlexItemCalculationInfo info = createFlexItemCalculationInfo((AbstractRenderer) imageRenderer);
+        Assert.assertEquals(40.0f, info.minContent, EPS);
+
+        image = new Image(new PdfFormXObject(new Rectangle(60, 150)));
+        image.setHeight(100);
+        image.setMinHeight(20);
+        image.setMaxHeight(75);
+        imageRenderer = image.createRendererSubTree();
+
+        info = createFlexItemCalculationInfo((AbstractRenderer) imageRenderer);
+        Assert.assertEquals(30.0f, info.minContent, EPS);
+    }
+
+    @Test
+    public void calculateMinContentForImageWithHeightAndWidthTest() {
+        Image image = new Image(new PdfFormXObject(new Rectangle(60, 150)));
+        image.setHeight(50);
+        image.setWidth(100);
+        IRenderer imageRenderer = image.createRendererSubTree();
+
+        FlexUtil.FlexItemCalculationInfo info = createFlexItemCalculationInfo((AbstractRenderer) imageRenderer);
+        Assert.assertEquals(60.0f, info.minContent, EPS);
+
+        image = new Image(new PdfFormXObject(new Rectangle(60, 150)));
+        image.setHeight(50);
+        image.setWidth(50);
+        imageRenderer = image.createRendererSubTree();
+
+        info = createFlexItemCalculationInfo((AbstractRenderer) imageRenderer);
+        Assert.assertEquals(50.0f, info.minContent, EPS);
+    }
+
+    private static FlexUtil.FlexItemCalculationInfo createFlexItemCalculationInfo(AbstractRenderer renderer) {
+        return new FlexUtil.FlexItemCalculationInfo(renderer, 0, 0, 0, 0, false);
+    }
 
     private static List<List<FlexItemInfo>> testFlex(List<UnitValue> flexBasisValues, List<Float> flexGrowValues,
             List<Float> flexShrinkValues) {