Implement lang attribute processing

DEVSIX-3243

Author: introfog

src/main/java/com/itextpdf/html2pdf/attach/impl/layout/Html2PdfProperty.java

@@ -91,4 +91,7 @@ public class Html2PdfProperty {
 
     /** The Constant FORM_FIELD_SELECTED. */
     public static final int FORM_FIELD_LABEL = PROPERTY_START + 14;
+
+    /** The Constant FORM_ACCESSIBILITY_LANGUAGE. */
+    public static final int FORM_ACCESSIBILITY_LANGUAGE = PROPERTY_START + 15;
 }

src/main/java/com/itextpdf/html2pdf/attach/impl/layout/PageMarginBoxDummyElement.java

@@ -73,7 +73,7 @@ public IAttributes getAttributes() {
 
     @Override
     public String getAttribute(String key) {
-        throw new UnsupportedOperationException();
+        return null;
     }
 
     @Override

src/main/java/com/itextpdf/html2pdf/attach/impl/layout/form/element/FormField.java

@@ -89,5 +89,4 @@ public <T1> T1 getDefaultProperty(int property) {
                 return super.<T1>getDefaultProperty(property);
         }
     }
-
 }

src/main/java/com/itextpdf/html2pdf/attach/impl/layout/form/renderer/AbstractFormFieldRenderer.java

@@ -45,7 +45,15 @@ This file is part of the iText (R) project.
 import com.itextpdf.html2pdf.LogMessageConstant;
 import com.itextpdf.html2pdf.attach.impl.layout.Html2PdfProperty;
 import com.itextpdf.html2pdf.attach.impl.layout.form.element.IFormField;
+import com.itextpdf.html2pdf.attach.util.AccessiblePropHelper;
+import com.itextpdf.io.font.PdfEncodings;
 import com.itextpdf.kernel.geom.Rectangle;
+import com.itextpdf.kernel.pdf.PdfDocument;
+import com.itextpdf.kernel.pdf.PdfString;
+import com.itextpdf.kernel.pdf.tagging.PdfStructElem;
+import com.itextpdf.kernel.pdf.tagging.StandardRoles;
+import com.itextpdf.kernel.pdf.tagutils.TagTreePointer;
+import com.itextpdf.layout.IPropertyContainer;
 import com.itextpdf.layout.layout.LayoutContext;
 import com.itextpdf.layout.layout.LayoutResult;
 import com.itextpdf.layout.layout.MinMaxWidthLayoutResult;
@@ -58,6 +66,9 @@ This file is part of the iText (R) project.
 import com.itextpdf.layout.renderer.DrawContext;
 import com.itextpdf.layout.renderer.ILeafElementRenderer;
 import com.itextpdf.layout.renderer.IRenderer;
+import com.itextpdf.layout.tagging.IAccessibleElement;
+
+import java.util.List;
 import org.slf4j.LoggerFactory;
 
 /**
@@ -126,6 +137,7 @@ public LayoutResult layout(LayoutContext layoutContext) {
                 setProperty(Property.FORCED_PLACEMENT, true);
             } else {
                 flatRenderer = childRenderers.get(0);
+                processLangAttribute();
                 childRenderers.clear();
                 childRenderers.add(flatRenderer);
                 adjustFieldLayout(layoutContext);
@@ -142,6 +154,7 @@ public LayoutResult layout(LayoutContext layoutContext) {
         }
         if (!childRenderers.isEmpty()) {
             flatRenderer = childRenderers.get(0);
+            processLangAttribute();
             childRenderers.clear();
             childRenderers.add(flatRenderer);
             adjustFieldLayout(layoutContext);
@@ -279,6 +292,15 @@ protected Float getContentWidth() {
         return super.retrieveWidth(0);
     }
 
+    /**
+     * Gets the accessibility language.
+     *
+     * @return the accessibility language
+     */
+    protected String getLang() {
+        return this.<String>getProperty(Html2PdfProperty.FORM_ACCESSIBILITY_LANGUAGE);
+    }
+
     //NOTE: should be removed in 3.0.0
     @Override
     protected Float retrieveWidth(float parentBoxWidth) {
@@ -292,4 +314,25 @@ protected Float retrieveWidth(float parentBoxWidth) {
     protected boolean isLayoutBasedOnFlatRenderer() {
         return true;
     }
+
+    protected void writeAcroFormFieldLangAttribute(PdfDocument pdfDoc) {
+        if (pdfDoc.isTagged()) {
+            TagTreePointer formParentPointer = pdfDoc.getTagStructureContext().getAutoTaggingPointer();
+            List<String> kidsRoles = formParentPointer.getKidsRoles();
+            int lastFormIndex = kidsRoles.lastIndexOf(StandardRoles.FORM);
+            TagTreePointer formPointer = formParentPointer.moveToKid(lastFormIndex);
+
+            if (getLang() != null) {
+                formPointer.getProperties().setLanguage(getLang());
+            }
+            formParentPointer.moveToParent();
+        }
+    }
+
+    private void processLangAttribute() {
+        IPropertyContainer propertyContainer = flatRenderer.getModelElement();
+        if (propertyContainer instanceof IAccessibleElement) {
+            AccessiblePropHelper.trySetLangAttribute((IAccessibleElement) propertyContainer, getLang());
+        }
+    }
 }

src/main/java/com/itextpdf/html2pdf/attach/impl/layout/form/renderer/AbstractSelectFieldRenderer.java

@@ -144,6 +144,15 @@ public void drawChildren(DrawContext drawContext) {
         }
     }
 
+    /**
+     * Gets the accessibility language.
+     *
+     * @return the accessibility language
+     */
+    protected String getLang() {
+        return this.<String>getProperty(Html2PdfProperty.FORM_ACCESSIBILITY_LANGUAGE);
+    }
+
     protected abstract IRenderer createFlatRenderer();
 
     protected abstract void applyAcroField(DrawContext drawContext);

src/main/java/com/itextpdf/html2pdf/attach/impl/layout/form/renderer/ButtonContainerRenderer.java

@@ -52,13 +52,17 @@ This file is part of the iText (R) project.
 import com.itextpdf.kernel.pdf.PdfDocument;
 import com.itextpdf.kernel.pdf.PdfPage;
 import com.itextpdf.kernel.pdf.annot.PdfAnnotation;
+import com.itextpdf.kernel.pdf.tagging.StandardRoles;
+import com.itextpdf.kernel.pdf.tagutils.TagTreePointer;
 import com.itextpdf.layout.property.Property;
 import com.itextpdf.layout.property.TransparentColor;
 import com.itextpdf.layout.property.UnitValue;
 import com.itextpdf.layout.renderer.BlockRenderer;
 import com.itextpdf.layout.renderer.DrawContext;
 import com.itextpdf.layout.renderer.IRenderer;
 
+import java.util.List;
+
 /**
  * The {@link AbstractOneLineTextFieldRenderer} implementation for buttons with kids.
  * @deprecated Will be renamed to {@code ButtonRenderer} in next major release.
@@ -99,6 +103,19 @@ public void draw(DrawContext drawContext) {
             if (forms.getField(name) == null) {
                 forms.addField(button, page);
             }
+
+            if (doc.isTagged()) {
+                TagTreePointer formParentPointer = doc.getTagStructureContext().getAutoTaggingPointer();
+                List<String> kidsRoles = formParentPointer.getKidsRoles();
+                int lastFormIndex = kidsRoles.lastIndexOf(StandardRoles.FORM);
+                TagTreePointer formPointer = formParentPointer.moveToKid(lastFormIndex);
+
+                String lang = this.<String>getProperty(Html2PdfProperty.FORM_ACCESSIBILITY_LANGUAGE);
+                if (lang != null) {
+                    formPointer.getProperties().setLanguage(lang);
+                }
+                formParentPointer.moveToParent();
+            }
         }
     }
 

src/main/java/com/itextpdf/html2pdf/attach/impl/layout/form/renderer/ButtonRenderer.java

@@ -155,6 +155,8 @@ protected void applyAcroField(DrawContext drawContext) {
         }
         applyDefaultFieldProperties(button);
         PdfAcroForm.getAcroForm(doc, true).addField(button, page);
+
+        writeAcroFormFieldLangAttribute(doc);
     }
 
     /* (non-Javadoc)

src/main/java/com/itextpdf/html2pdf/attach/impl/layout/form/renderer/CheckBoxRenderer.java

@@ -133,6 +133,8 @@ protected void applyAcroField(DrawContext drawContext) {
         PdfPage page = doc.getPage(occupiedArea.getPageNumber());
         PdfButtonFormField checkBox = PdfFormField.createCheckBox(doc, area, name, isBoxChecked() ? "Yes" : "Off");
         PdfAcroForm.getAcroForm(doc, true).addField(checkBox, page);
+
+        writeAcroFormFieldLangAttribute(doc);
     }
 
     @Override

src/main/java/com/itextpdf/html2pdf/attach/impl/layout/form/renderer/InputFieldRenderer.java

@@ -183,6 +183,8 @@ protected void applyAcroField(DrawContext drawContext) {
         }
         applyDefaultFieldProperties(inputField);
         PdfAcroForm.getAcroForm(doc, true).addField(inputField, page);
+
+        writeAcroFormFieldLangAttribute(doc);
     }
 
     @Override

src/main/java/com/itextpdf/html2pdf/attach/impl/layout/form/renderer/RadioRenderer.java

@@ -151,13 +151,17 @@ protected void applyAcroField(DrawContext drawContext) {
         if (isBoxChecked()) {
             radioGroup.setValue(getModelId());
         }
-        PdfFormField.createRadioButton(doc, area, radioGroup, getModelId())
-                .setCheckType(PdfFormField.TYPE_CIRCLE);
+
+        PdfFormField radio = PdfFormField.createRadioButton(doc, area, radioGroup, getModelId());
+        radio.setCheckType(PdfFormField.TYPE_CIRCLE);
+
         if (addNew) {
             form.addField(radioGroup, page);
         } else {
             form.replaceField(getModelId(), radioGroup);
         }
+
+        writeAcroFormFieldLangAttribute(doc);
     }
 
     @Override