Enabled support for PDF/A-1a now that we have Tagged PDF, Natural Language Specification and alternate descriptions (fox:alt-text).

git-svn-id: https://svn.apache.org/repos/asf/xmlgraphics/fop/branches/Temp_Accessibility@765979 13f79535-47bb-0310-9956-ffa450edef68

src/java/org/apache/fop/pdf/PDFAMode.java

@@ -44,7 +44,18 @@ public final class PDFAMode {
         return this.name;
     }
 
-    /** @return true if this mode obey the restrictions established by PDF/A-1b. */
+    /**
+     * Indicates whether this mode obeys the restrictions established by PDF/A-1a.
+     * @return true if this mode obeys the restrictions established by PDF/A-1a.
+     */
+    public boolean isPDFA1LevelA() {
+        return (this != DISABLED);
+    }
+
+    /**
+     * Indicates whether this mode obeys the restrictions established by PDF/A-1b.
+     * @return true if this mode obeys the restrictions established by PDF/A-1b.
+     */
     public boolean isPDFA1LevelB() {
         return (this != DISABLED);
         //PDF/A-1a is a superset of PDF/A-1b!

src/java/org/apache/fop/pdf/PDFProfile.java

@@ -58,9 +58,6 @@ public class PDFProfile {
      */
     protected void validateProfileCombination() {
         if (pdfAMode != PDFAMode.DISABLED) {
-            if (pdfAMode == PDFAMode.PDFA_1A) {
-                throw new UnsupportedOperationException("PDF/A-1a is not implemented, yet");
-            }
             if (pdfAMode == PDFAMode.PDFA_1B) {
                 if (pdfXMode != PDFXMode.DISABLED && pdfXMode != PDFXMode.PDFX_3_2003) {
                     throw new PDFConformanceException(
@@ -192,6 +189,32 @@ public class PDFProfile {
         }
     }
 
+    /**
+     * Checks a few things required for tagged PDF.
+     */
+    public void verifyTaggedPDF() {
+        if (getPDFAMode().isPDFA1LevelA()) {
+            final String err = "{0} requires the {1} dictionary entry to be set";
+            PDFDictionary markInfo = getDocument().getRoot().getMarkInfo();
+            if (markInfo == null) {
+                throw new PDFConformanceException(format(
+                        "{0} requires the MarkInfo dictionary to be present", getPDFAMode()));
+            }
+            if (!Boolean.TRUE.equals(markInfo.get("Marked"))) {
+                throw new PDFConformanceException(format(err,
+                        new Object[] {getPDFAMode(), "Marked"}));
+            }
+            if (getDocument().getRoot().getStructTreeRoot() == null) {
+                throw new PDFConformanceException(format(err,
+                        new Object[] {getPDFAMode(), "StructTreeRoot"}));
+            }
+            if (getDocument().getRoot().getLanguage() == null) {
+                throw new PDFConformanceException(format(err,
+                        new Object[] {getPDFAMode(), "Lang"}));
+            }
+        }
+    }
+
     /** @return true if the ID entry must be present in the trailer. */
     public boolean isIDEntryRequired() {
         return isPDFAActive() || isPDFXActive();

src/java/org/apache/fop/pdf/PDFRoot.java

@@ -19,6 +19,9 @@
 
 package org.apache.fop.pdf;
 
+import java.io.IOException;
+import java.io.OutputStream;
+
 /**
  * Class representing a Root (/Catalog) object.
  */
@@ -56,7 +59,7 @@ public class PDFRoot extends PDFDictionary {
      * object must be created before the PDF document is
      * generated, but it is not assigned an object ID until
      * it is about to be written (immediately before the xref
-     * table as part of the trsailer). (mark-fop@inomial.com)
+     * table as part of the trailer). (mark-fop@inomial.com)
      *
      * @param objnum the object's number
      * @param pages the PDFPages object
@@ -68,6 +71,12 @@ public class PDFRoot extends PDFDictionary {
         setRootPages(pages);
     }
 
+    /** {@inheritDoc} */
+    protected int output(OutputStream stream) throws IOException {
+        getDocument().getProfile().verifyTaggedPDF();
+        return super.output(stream);
+    }
+
     /**
      * Set the page mode for the PDF document.
      *
@@ -280,4 +289,11 @@ public class PDFRoot extends PDFDictionary {
         put("MarkInfo", dict);  //new PDFMarkInfo()
     }
 
+    /**
+     * Returns the MarkInfo dictionary.
+     * @return the MarkInfo dictionary (or null if it's not present)
+     */
+    public PDFDictionary getMarkInfo() {
+        return (PDFDictionary)get("MarkInfo");
+    }
 }

src/java/org/apache/fop/render/pdf/PDFDocumentHandler.java

@@ -306,8 +306,15 @@ public class PDFDocumentHandler extends AbstractBinaryWritingIFDocumentHandler {
         if (getUserAgent().isAccessibilityEnabled()) {
             try {
                 if (this.pdfDoc.getRoot().getLanguage() == null) {
-                    //No language has been set on the first page-sequence, so fall back to "en".
-                    this.pdfDoc.getRoot().setLanguage("en");
+                    String fallbackLanguage;
+                    if (this.pdfDoc.getProfile().getPDFAMode().isPDFA1LevelA()) {
+                        //According to Annex B of ISO-19005-1:2005(E), section B.2
+                        fallbackLanguage = "x-unknown";
+                    } else {
+                        //No language has been set on the first page-sequence, so fall back to "en".
+                        fallbackLanguage = "en";
+                    }
+                    this.pdfDoc.getRoot().setLanguage(fallbackLanguage);
                 }
 
                 if (reducedFOTree == null) {

src/java/org/apache/fop/render/pdf/PDFRenderingUtil.java

@@ -37,6 +37,7 @@ import org.apache.xmlgraphics.xmp.Metadata;
 import org.apache.xmlgraphics.xmp.schemas.XMPBasicAdapter;
 import org.apache.xmlgraphics.xmp.schemas.XMPBasicSchema;
 
+import org.apache.fop.accessibility.AccessibilityUtil;
 import org.apache.fop.apps.FOUserAgent;
 import org.apache.fop.fo.extensions.xmp.XMPMetadata;
 import org.apache.fop.pdf.PDFAMode;
@@ -109,7 +110,7 @@ class PDFRenderingUtil implements PDFConfigurationConstants {
 
     private void initialize() {
         PDFEncryptionParams params
-        = (PDFEncryptionParams)userAgent.getRendererOptions().get(ENCRYPTION_PARAMS);
+            = (PDFEncryptionParams)userAgent.getRendererOptions().get(ENCRYPTION_PARAMS);
         if (params != null) {
             this.encryptionParams = params; //overwrite if available
         }
@@ -161,6 +162,10 @@ class PDFRenderingUtil implements PDFConfigurationConstants {
         if (s != null) {
             this.pdfAMode = PDFAMode.valueOf(s);
         }
+        if (this.pdfAMode.isPDFA1LevelA()) {
+            //Enable accessibility if PDF/A-1a is enabled because it requires tagged PDF.
+            userAgent.getRendererOptions().put(AccessibilityUtil.ACCESSIBILITY, Boolean.TRUE);
+        }
         s = (String)userAgent.getRendererOptions().get(PDF_X_MODE);
         if (s != null) {
             this.pdfXMode = PDFXMode.valueOf(s);