XMPCore/src/com/adobe/xmp/impl/XMPNormalizer.java - platform/external/xmp_toolkit - Git at Google

 // =================================================================================================
 // ADOBE SYSTEMS INCORPORATED
 // Copyright 2006 Adobe Systems Incorporated
 // All Rights Reserved
 //
 // NOTICE:  Adobe permits you to use, modify, and distribute this file in accordance with the terms
 // of the Adobe license agreement accompanying it.
 // =================================================================================================

 package com.adobe.xmp.impl;

 import java.util.Calendar;
 import java.util.HashMap;
 import java.util.Iterator;
 import java.util.Map;

 import com.adobe.xmp.XMPConst;
 import com.adobe.xmp.XMPDateTime;
 import com.adobe.xmp.XMPError;
 import com.adobe.xmp.XMPException;
 import com.adobe.xmp.XMPMeta;
 import com.adobe.xmp.XMPMetaFactory;
 import com.adobe.xmp.XMPUtils;
 import com.adobe.xmp.impl.xpath.XMPPath;
 import com.adobe.xmp.impl.xpath.XMPPathParser;
 import com.adobe.xmp.options.ParseOptions;
 import com.adobe.xmp.options.PropertyOptions;
 import com.adobe.xmp.properties.XMPAliasInfo;

 /**
  * @since   Aug 18, 2006
  */
 public class XMPNormalizer
 {
 	/** caches the correct dc-property array forms */
 	private static Map dcArrayForms;
 	/** init char tables */
 	static
 	{
 		initDCArrays();
 	}


 	/**
 	 * Hidden constructor
 	 */
 	private XMPNormalizer()
 	{
 		// EMPTY
 	}


 	/**
 	 * Normalizes a raw parsed XMPMeta-Object
 	 * @param xmp the raw metadata object
 	 * @param options the parsing options
 	 * @return Returns the normalized metadata object
 	 * @throws XMPException Collects all severe processing errors.
 	 */
 	static XMPMeta process(XMPMetaImpl xmp, ParseOptions options) throws XMPException
 	{
 		XMPNode tree = xmp.getRoot();

 		touchUpDataModel(xmp);
 		moveExplicitAliases(tree, options);

 		tweakOldXMP(tree);

 		deleteEmptySchemas(tree);

 		return xmp;
 	}


 	/**
 	 * Tweak old XMP: Move an instance ID from rdf:about to the
 	 * <em>xmpMM:InstanceID</em> property. An old instance ID usually looks
 	 * like &quot;uuid:bac965c4-9d87-11d9-9a30-000d936b79c4&quot;, plus InDesign
 	 * 3.0 wrote them like &quot;bac965c4-9d87-11d9-9a30-000d936b79c4&quot;. If
 	 * the name looks like a UUID simply move it to <em>xmpMM:InstanceID</em>,
 	 * don't worry about any existing <em>xmpMM:InstanceID</em>. Both will
 	 * only be present when a newer file with the <em>xmpMM:InstanceID</em>
 	 * property is updated by an old app that uses <em>rdf:about</em>.
 	 *
 	 * @param tree the root of the metadata tree
 	 * @throws XMPException Thrown if tweaking fails.
 	 */
 	private static void tweakOldXMP(XMPNode tree) throws XMPException
 	{
 		if (tree.getName() != null  &&  tree.getName().length() >= Utils.UUID_LENGTH)
 		{
 			String nameStr = tree.getName().toLowerCase();
 			if (nameStr.startsWith("uuid:"))
 			{
 				nameStr = nameStr.substring(5);
 			}

 			if (Utils.checkUUIDFormat(nameStr))
 			{
 				// move UUID to xmpMM:InstanceID and remove it from the root node
 				XMPPath path = XMPPathParser.expandXPath(XMPConst.NS_XMP_MM, "InstanceID");
 				XMPNode idNode = XMPNodeUtils.findNode (tree, path, true, null);
 				if (idNode != null)
 				{
 					idNode.setOptions(null);	// Clobber any existing xmpMM:InstanceID.
 					idNode.setValue("uuid:" + nameStr);
 					idNode.removeChildren();
 					idNode.removeQualifiers();
 					tree.setName(null);
 				}
 				else
 				{
 					throw new XMPException("Failure creating xmpMM:InstanceID",
 							XMPError.INTERNALFAILURE);
 				}
 			}
 		}
 	}


 	/**
 	 * Visit all schemas to do general fixes and handle special cases.
 	 *
 	 * @param xmp the metadata object implementation
 	 * @throws XMPException Thrown if the normalisation fails.
 	 */
 	private static void touchUpDataModel(XMPMetaImpl xmp) throws XMPException
 	{
 		// make sure the DC schema is existing, because it might be needed within the normalization
 		// if not touched it will be removed by removeEmptySchemas
 		XMPNodeUtils.findSchemaNode(xmp.getRoot(), XMPConst.NS_DC, true);

 		// Do the special case fixes within each schema.
 		for (Iterator it = xmp.getRoot().iterateChildren(); it.hasNext();)
 		{
 			XMPNode currSchema = (XMPNode) it.next();
 			if (XMPConst.NS_DC.equals(currSchema.getName()))
 			{
 				normalizeDCArrays(currSchema);
 			}
 			else if (XMPConst.NS_EXIF.equals(currSchema.getName()))
 			{
 				// Do a special case fix for exif:GPSTimeStamp.
 				fixGPSTimeStamp(currSchema);
 				XMPNode arrayNode = XMPNodeUtils.findChildNode(currSchema, "exif:UserComment",
 						false);
 				if (arrayNode != null)
 				{
 					repairAltText(arrayNode);
 				}
 			}
 			else if (XMPConst.NS_DM.equals(currSchema.getName()))
 			{
 				// Do a special case migration of xmpDM:copyright to
 				// dc:rights['x-default'].
 				XMPNode dmCopyright = XMPNodeUtils.findChildNode(currSchema, "xmpDM:copyright",
 						false);
 				if (dmCopyright != null)
 				{
 					migrateAudioCopyright(xmp, dmCopyright);
 				}
 			}
 			else if (XMPConst.NS_XMP_RIGHTS.equals(currSchema.getName()))
 			{
 				XMPNode arrayNode = XMPNodeUtils.findChildNode(currSchema, "xmpRights:UsageTerms",
 						false);
 				if (arrayNode != null)
 				{
 					repairAltText(arrayNode);
 				}
 			}
 		}
 	}


 	/**
 	 * Undo the denormalization performed by the XMP used in Acrobat 5.<br>
 	 * If a Dublin Core array had only one item, it was serialized as a simple
 	 * property. <br>
 	 * The <code>xml:lang</code> attribute was dropped from an
 	 * <code>alt-text</code> item if the language was <code>x-default</code>.
 	 *
 	 * @param dcSchema the DC schema node
 	 * @throws XMPException Thrown if normalization fails
 	 */
 	private static void normalizeDCArrays(XMPNode dcSchema) throws XMPException
 	{
 		for (int i = 1; i <= dcSchema.getChildrenLength(); i++)
 		{
 			XMPNode currProp = dcSchema.getChild(i);

 			PropertyOptions arrayForm = (PropertyOptions) dcArrayForms.get(currProp.getName());
 			if (arrayForm == null)
 			{
 				continue;
 			}
 			else if (currProp.getOptions().isSimple())
 			{
 				// create a new array and add the current property as child,
 				// if it was formerly simple
 				XMPNode newArray = new XMPNode(currProp.getName(), arrayForm);
 				currProp.setName(XMPConst.ARRAY_ITEM_NAME);
 				newArray.addChild(currProp);
 				dcSchema.replaceChild(i, newArray);

 				// fix language alternatives
 				if (arrayForm.isArrayAltText()  &&  !currProp.getOptions().getHasLanguage())
 				{
 					XMPNode newLang = new XMPNode(XMPConst.XML_LANG, XMPConst.X_DEFAULT, null);
 					currProp.addQualifier(newLang);
 				}
 			}
 			else
 			{
 				// clear array options and add corrected array form if it has been an array before
 				currProp.getOptions().setOption(
 					PropertyOptions.ARRAY  |
 					PropertyOptions.ARRAY_ORDERED  |
 					PropertyOptions.ARRAY_ALTERNATE  |
 					PropertyOptions.ARRAY_ALT_TEXT,
 					false);
 				currProp.getOptions().mergeWith(arrayForm);

 				if (arrayForm.isArrayAltText())
 				{
 					// applying for "dc:description", "dc:rights", "dc:title"
 					repairAltText(currProp);
 				}
 			}

 		}
 	}


 	/**
 	 * Make sure that the array is well-formed AltText. Each item must be simple
 	 * and have an "xml:lang" qualifier. If repairs are needed, keep simple
 	 * non-empty items by adding the "xml:lang" with value "x-repair".
 	 * @param arrayNode the property node of the array to repair.
 	 * @throws XMPException Forwards unexpected exceptions.
 	 */
 	private static void repairAltText(XMPNode arrayNode) throws XMPException
 	{
 		if (arrayNode == null  ||
 			!arrayNode.getOptions().isArray())
 		{
 			// Already OK or not even an array.
 			return;
 		}

 		// fix options
 		arrayNode.getOptions().setArrayOrdered(true).setArrayAlternate(true).setArrayAltText(true);

 		for (Iterator it = arrayNode.iterateChildren(); it.hasNext();)
 		{
 			XMPNode currChild = (XMPNode) it.next();
 			if (currChild.getOptions().isCompositeProperty())
 			{
 				// Delete non-simple children.
 				it.remove();
 			}
 			else if (!currChild.getOptions().getHasLanguage())
 			{
 				String childValue = currChild.getValue();
 				if (childValue == null  ||  childValue.length() == 0)
 				{
 					// Delete empty valued children that have no xml:lang.
 					it.remove();
 				}
 				else
 				{
 					// Add an xml:lang qualifier with the value "x-repair".
 					XMPNode repairLang = new XMPNode(XMPConst.XML_LANG, "x-repair", null);
 					currChild.addQualifier(repairLang);
 				}
 			}
 		}
 	}


 	/**
 	 * Visit all of the top level nodes looking for aliases. If there is
 	 * no base, transplant the alias subtree. If there is a base and strict
 	 * aliasing is on, make sure the alias and base subtrees match.
 	 *
 	 * @param tree the root of the metadata tree
 	 * @param options th parsing options
 	 * @throws XMPException Forwards XMP errors
 	 */
 	private static void moveExplicitAliases(XMPNode tree, ParseOptions options)
 			throws XMPException
 	{
 		if (!tree.getHasAliases())
 		{
 			return;
 		}
 		tree.setHasAliases(false);

 		boolean strictAliasing = options.getStrictAliasing();

 		for (Iterator schemaIt = tree.getUnmodifiableChildren().iterator(); schemaIt.hasNext();)
 		{
 			XMPNode currSchema = (XMPNode) schemaIt.next();
 			if (!currSchema.getHasAliases())
 			{
 				continue;
 			}

 			for (Iterator propertyIt = currSchema.iterateChildren(); propertyIt.hasNext();)
 			{
 				XMPNode currProp = (XMPNode) propertyIt.next();

 				if (!currProp.isAlias())
 				{
 					continue;
 				}

 				currProp.setAlias(false);

 				// Find the base path, look for the base schema and root node.
 				XMPAliasInfo info = XMPMetaFactory.getSchemaRegistry()
 						.findAlias(currProp.getName());
 				if (info != null)
 				{
 					// find or create schema
 					XMPNode baseSchema = XMPNodeUtils.findSchemaNode(tree, info
 							.getNamespace(), null, true);
 					baseSchema.setImplicit(false);

 					XMPNode baseNode = XMPNodeUtils
 							.findChildNode(baseSchema,
 								info.getPrefix() + info.getPropName(), false);
 					if (baseNode == null)
 					{
 						if (info.getAliasForm().isSimple())
 						{
 							// A top-to-top alias, transplant the property.
 							// change the alias property name to the base name
 							String qname = info.getPrefix() + info.getPropName();
 							currProp.setName(qname);
 							baseSchema.addChild(currProp);
 							// remove the alias property
 							propertyIt.remove();
 						}
 						else
 						{
 							// An alias to an array item,
 							// create the array and transplant the property.
 							baseNode = new XMPNode(info.getPrefix() + info.getPropName(), info
 									.getAliasForm().toPropertyOptions());
 							baseSchema.addChild(baseNode);
 							transplantArrayItemAlias (propertyIt, currProp, baseNode);
 						}

 					}
 					else if (info.getAliasForm().isSimple())
 					{
 						// The base node does exist and this is a top-to-top alias.
 						// Check for conflicts if strict aliasing is on.
 						// Remove and delete the alias subtree.
 						if (strictAliasing)
 						{
 							compareAliasedSubtrees (currProp, baseNode, true);
 						}

 						propertyIt.remove();
 					}
 					else
 					{
 						// This is an alias to an array item and the array exists.
 						// Look for the aliased item.
 						// Then transplant or check & delete as appropriate.

 						XMPNode  itemNode = null;
 						if (info.getAliasForm().isArrayAltText())
 						{
 							int xdIndex = XMPNodeUtils.lookupLanguageItem(baseNode,
 									XMPConst.X_DEFAULT);
 							if (xdIndex != -1)
 							{
 								itemNode = baseNode.getChild(xdIndex);
 							}
 						}
 						else if (baseNode.hasChildren())
 						{
 							itemNode = baseNode.getChild(1);
 						}

 						if (itemNode == null)
 						{
 							transplantArrayItemAlias (propertyIt, currProp, baseNode);
 						}
 						else
 						{
 							if (strictAliasing)
 							{
 								compareAliasedSubtrees (currProp, itemNode, true);
 							}

 							propertyIt.remove();
 						}
 					}
 				}
 			}
 			currSchema.setHasAliases(false);
 		}
 	}


 	/**
 	 * Moves an alias node of array form to another schema into an array
 	 * @param propertyIt the property iterator of the old schema (used to delete the property)
 	 * @param childNode the node to be moved
 	 * @param baseArray the base array for the array item
 	 * @throws XMPException Forwards XMP errors
 	 */
 	private static void transplantArrayItemAlias(Iterator propertyIt, XMPNode childNode,
 			XMPNode baseArray) throws XMPException
 	{
 		if (baseArray.getOptions().isArrayAltText())
 		{
 			if (childNode.getOptions().getHasLanguage())
 			{
 				throw new XMPException("Alias to x-default already has a language qualifier",
 						XMPError.BADXMP);
 			}

 			XMPNode langQual = new XMPNode(XMPConst.XML_LANG, XMPConst.X_DEFAULT, null);
 			childNode.addQualifier(langQual);
 		}

 		propertyIt.remove();
 		childNode.setName(XMPConst.ARRAY_ITEM_NAME);
 		baseArray.addChild(childNode);
 	}


 	/**
 	 * Fixes the GPS Timestamp in EXIF.
 	 * @param exifSchema the EXIF schema node
 	 * @throws XMPException Thrown if the date conversion fails.
 	 */
 	private static void fixGPSTimeStamp(XMPNode exifSchema)
 			throws XMPException
 	{
 		// Note: if dates are not found the convert-methods throws an exceptions,
 		// 		 and this methods returns.
 		XMPNode gpsDateTime = XMPNodeUtils.findChildNode(exifSchema, "exif:GPSTimeStamp", false);
 		if (gpsDateTime == null)
 		{
 			return;
 		}

 		try
 		{
 			XMPDateTime binGPSStamp;
 			XMPDateTime binOtherDate;

 			binGPSStamp = XMPUtils.convertToDate(gpsDateTime.getValue());
 			if (binGPSStamp.getYear() != 0  ||
 				binGPSStamp.getMonth() != 0  ||
 				binGPSStamp.getDay() != 0)
 			{
 				return;
 			}

 			XMPNode otherDate = XMPNodeUtils.findChildNode(exifSchema, "exif:DateTimeOriginal",
 					false);
 			if (otherDate == null)
 			{
 				otherDate = XMPNodeUtils.findChildNode(exifSchema, "exif:DateTimeDigitized", false);
 			}

 			binOtherDate = XMPUtils.convertToDate(otherDate.getValue());
 			Calendar cal = binGPSStamp.getCalendar();
 			cal.set(Calendar.YEAR, binOtherDate.getYear());
 			cal.set(Calendar.MONTH, binOtherDate.getMonth());
 			cal.set(Calendar.DAY_OF_MONTH, binOtherDate.getDay());
 			binGPSStamp = new XMPDateTimeImpl(cal);
 			gpsDateTime.setValue(XMPUtils.convertFromDate (binGPSStamp));
 		}
 		catch (XMPException e)
 		{
 			// Don't let a missing or bad date stop other things.
 			return;
 		}
 	}


 	/**
 	 * Remove all empty schemas from the metadata tree that were generated during the rdf parsing.
 	 * @param tree the root of the metadata tree
 	 */
 	private static void deleteEmptySchemas(XMPNode tree)
 	{
 		// Delete empty schema nodes. Do this last, other cleanup can make empty
 		// schema.

 		for (Iterator it = tree.iterateChildren(); it.hasNext();)
 		{
 			XMPNode schema = (XMPNode) it.next();
 			if (!schema.hasChildren())
 			{
 				it.remove();
 			}
 		}
 	}


 	/**
 	 * The outermost call is special. The names almost certainly differ. The
 	 * qualifiers (and hence options) will differ for an alias to the x-default
 	 * item of a langAlt array.
 	 *
 	 * @param aliasNode the alias node
 	 * @param baseNode the base node of the alias
 	 * @param outerCall marks the outer call of the recursion
 	 * @throws XMPException Forwards XMP errors
 	 */
 	private static void compareAliasedSubtrees(XMPNode aliasNode, XMPNode baseNode,
 			boolean outerCall) throws XMPException
 	{
 		if (!aliasNode.getValue().equals(baseNode.getValue())  ||
 			aliasNode.getChildrenLength() != baseNode.getChildrenLength())
 		{
 			throw new XMPException("Mismatch between alias and base nodes", XMPError.BADXMP);
 		}

 		if (
 				!outerCall  &&
 				(!aliasNode.getName().equals(baseNode.getName())  ||
 				 !aliasNode.getOptions().equals(baseNode.getOptions())  ||
 				 aliasNode.getQualifierLength() != baseNode.getQualifierLength())
 		   )
 	    {
 			throw new XMPException("Mismatch between alias and base nodes",
 				XMPError.BADXMP);
 		}

 		for (Iterator an = aliasNode.iterateChildren(),
 					  bn = baseNode.iterateChildren();
 			 an.hasNext() && bn.hasNext();)
 		{
 			XMPNode aliasChild = (XMPNode) an.next();
 			XMPNode baseChild =  (XMPNode) bn.next();
 			compareAliasedSubtrees (aliasChild, baseChild, false);
 		}


 		for (Iterator an = aliasNode.iterateQualifier(),
 					  bn = baseNode.iterateQualifier();
 			 an.hasNext() && bn.hasNext();)
 		{
 			XMPNode aliasQual = (XMPNode) an.next();
 			XMPNode baseQual =  (XMPNode) bn.next();
 			compareAliasedSubtrees (aliasQual, baseQual, false);
 		}
 	}


 	/**
 	 * The initial support for WAV files mapped a legacy ID3 audio copyright
 	 * into a new xmpDM:copyright property. This is special case code to migrate
 	 * that into dc:rights['x-default']. The rules:
 	 *
 	 * <pre>
 	 * 1. If there is no dc:rights array, or an empty array -
 	 *    Create one with dc:rights['x-default'] set from double linefeed and xmpDM:copyright.
 	 *
 	 * 2. If there is a dc:rights array but it has no x-default item -
 	 *    Create an x-default item as a copy of the first item then apply rule #3.
 	 *
 	 * 3. If there is a dc:rights array with an x-default item,
 	 *    Look for a double linefeed in the value.
 	 *     A. If no double linefeed, compare the x-default value to the xmpDM:copyright value.
 	 *         A1. If they match then leave the x-default value alone.
 	 *         A2. Otherwise, append a double linefeed and
 	 *             the xmpDM:copyright value to the x-default value.
 	 *     B. If there is a double linefeed, compare the trailing text to the xmpDM:copyright value.
 	 *         B1. If they match then leave the x-default value alone.
 	 *         B2. Otherwise, replace the trailing x-default text with the xmpDM:copyright value.
 	 *
 	 * 4. In all cases, delete the xmpDM:copyright property.
 	 * </pre>
 	 *
 	 * @param xmp the metadata object
 	 * @param dmCopyright the "dm:copyright"-property
 	 */
 	private static void	migrateAudioCopyright (XMPMeta xmp, XMPNode dmCopyright)
 	{
 		try
 		{
 			XMPNode dcSchema = XMPNodeUtils.findSchemaNode(
 				((XMPMetaImpl) xmp).getRoot(), XMPConst.NS_DC, true);

 			String dmValue = dmCopyright.getValue();
 			String doubleLF = "\n\n";

 			XMPNode dcRightsArray = XMPNodeUtils.findChildNode (dcSchema, "dc:rights", false);

 			if (dcRightsArray == null  ||  !dcRightsArray.hasChildren())
 			{
 				// 1. No dc:rights array, create from double linefeed and xmpDM:copyright.
 				dmValue = doubleLF + dmValue;
 				xmp.setLocalizedText(XMPConst.NS_DC, "rights", "", XMPConst.X_DEFAULT, dmValue,
 						null);
 			}
 			else
 			{
 				int xdIndex = XMPNodeUtils.lookupLanguageItem(dcRightsArray, XMPConst.X_DEFAULT);

 				if (xdIndex < 0)
 				{
 					// 2. No x-default item, create from the first item.
 					String firstValue = dcRightsArray.getChild(1).getValue();
 					xmp.setLocalizedText (XMPConst.NS_DC, "rights", "", XMPConst.X_DEFAULT,
 						firstValue, null);
 					xdIndex = XMPNodeUtils.lookupLanguageItem(dcRightsArray, XMPConst.X_DEFAULT);
 				}

 				// 3. Look for a double linefeed in the x-default value.
 				XMPNode defaultNode = dcRightsArray.getChild(xdIndex);
 				String defaultValue = defaultNode.getValue();
 				int lfPos = defaultValue.indexOf(doubleLF);

 				if (lfPos < 0)
 				{
 					// 3A. No double LF, compare whole values.
 					if (!dmValue.equals(defaultValue))
 					{
 						// 3A2. Append the xmpDM:copyright to the x-default
 						// item.
 						defaultNode.setValue(defaultValue + doubleLF + dmValue);
 					}
 				}
 				else
 				{
 					// 3B. Has double LF, compare the tail.
 					if (!defaultValue.substring(lfPos + 2).equals(dmValue))
 					{
 						// 3B2. Replace the x-default tail.
 						defaultNode.setValue(defaultValue.substring(0, lfPos + 2) + dmValue);
 					}
 				}

 			}

 			// 4. Get rid of the xmpDM:copyright.
 			dmCopyright.getParent().removeChild(dmCopyright);
 		}
 		catch (XMPException e)
 		{
 			// Don't let failures (like a bad dc:rights form) stop other
 			// cleanup.
 		}
 	}


 	/**
 	 * Initializes the map that contains the known arrays, that are fixed by
 	 * {@link XMPNormalizer#normalizeDCArrays(XMPNode)}.
 	 */
 	private static void initDCArrays()
 	{
 		dcArrayForms = new HashMap();

 		// Properties supposed to be a "Bag".
 		PropertyOptions bagForm = new PropertyOptions();
 		bagForm.setArray(true);
 		dcArrayForms.put("dc:contributor", bagForm);
 		dcArrayForms.put("dc:language", bagForm);
 		dcArrayForms.put("dc:publisher", bagForm);
 		dcArrayForms.put("dc:relation", bagForm);
 		dcArrayForms.put("dc:subject", bagForm);
 		dcArrayForms.put("dc:type", bagForm);

 		// Properties supposed to be a "Seq".
 		PropertyOptions seqForm = new PropertyOptions();
 		seqForm.setArray(true);
 		seqForm.setArrayOrdered(true);
 		dcArrayForms.put("dc:creator", seqForm);
 		dcArrayForms.put("dc:date", seqForm);

 		// Properties supposed to be an "Alt" in alternative-text form.
 		PropertyOptions altTextForm = new PropertyOptions();
 		altTextForm.setArray(true);
 		altTextForm.setArrayOrdered(true);
 		altTextForm.setArrayAlternate(true);
 		altTextForm.setArrayAltText(true);
 		dcArrayForms.put("dc:description", altTextForm);
 		dcArrayForms.put("dc:rights", altTextForm);
 		dcArrayForms.put("dc:title", altTextForm);
 	}
 }
	// =================================================================================================
	// ADOBE SYSTEMS INCORPORATED
	// Copyright 2006 Adobe Systems Incorporated
	// All Rights Reserved
	//
	// NOTICE: Adobe permits you to use, modify, and distribute this file in accordance with the terms
	// of the Adobe license agreement accompanying it.
	// =================================================================================================

	package com.adobe.xmp.impl;

	import java.util.Calendar;
	import java.util.HashMap;
	import java.util.Iterator;
	import java.util.Map;

	import com.adobe.xmp.XMPConst;
	import com.adobe.xmp.XMPDateTime;
	import com.adobe.xmp.XMPError;
	import com.adobe.xmp.XMPException;
	import com.adobe.xmp.XMPMeta;
	import com.adobe.xmp.XMPMetaFactory;
	import com.adobe.xmp.XMPUtils;
	import com.adobe.xmp.impl.xpath.XMPPath;
	import com.adobe.xmp.impl.xpath.XMPPathParser;
	import com.adobe.xmp.options.ParseOptions;
	import com.adobe.xmp.options.PropertyOptions;
	import com.adobe.xmp.properties.XMPAliasInfo;

	/**
	* @since Aug 18, 2006
	*/
	public class XMPNormalizer
	{
	/** caches the correct dc-property array forms */
	private static Map dcArrayForms;
	/** init char tables */
	static
	{
	initDCArrays();
	}


	/**
	* Hidden constructor
	*/
	private XMPNormalizer()
	{
	// EMPTY
	}


	/**
	* Normalizes a raw parsed XMPMeta-Object
	* @param xmp the raw metadata object
	* @param options the parsing options
	* @return Returns the normalized metadata object
	* @throws XMPException Collects all severe processing errors.
	*/
	static XMPMeta process(XMPMetaImpl xmp, ParseOptions options) throws XMPException
	{
	XMPNode tree = xmp.getRoot();

	touchUpDataModel(xmp);
	moveExplicitAliases(tree, options);

	tweakOldXMP(tree);

	deleteEmptySchemas(tree);

	return xmp;
	}


	/**
	* Tweak old XMP: Move an instance ID from rdf:about to the
	* <em>xmpMM:InstanceID</em> property. An old instance ID usually looks
	* like "uuid:bac965c4-9d87-11d9-9a30-000d936b79c4", plus InDesign
	* 3.0 wrote them like "bac965c4-9d87-11d9-9a30-000d936b79c4". If
	* the name looks like a UUID simply move it to <em>xmpMM:InstanceID</em>,
	* don't worry about any existing <em>xmpMM:InstanceID</em>. Both will
	* only be present when a newer file with the <em>xmpMM:InstanceID</em>
	* property is updated by an old app that uses <em>rdf:about</em>.
	*
	* @param tree the root of the metadata tree
	* @throws XMPException Thrown if tweaking fails.
	*/
	private static void tweakOldXMP(XMPNode tree) throws XMPException
	{
	if (tree.getName() != null && tree.getName().length() >= Utils.UUID_LENGTH)
	{
	String nameStr = tree.getName().toLowerCase();
	if (nameStr.startsWith("uuid:"))
	{
	nameStr = nameStr.substring(5);
	}

	if (Utils.checkUUIDFormat(nameStr))
	{
	// move UUID to xmpMM:InstanceID and remove it from the root node
	XMPPath path = XMPPathParser.expandXPath(XMPConst.NS_XMP_MM, "InstanceID");
	XMPNode idNode = XMPNodeUtils.findNode (tree, path, true, null);
	if (idNode != null)
	{
	idNode.setOptions(null); // Clobber any existing xmpMM:InstanceID.
	idNode.setValue("uuid:" + nameStr);
	idNode.removeChildren();
	idNode.removeQualifiers();
	tree.setName(null);
	}
	else
	{
	throw new XMPException("Failure creating xmpMM:InstanceID",
	XMPError.INTERNALFAILURE);
	}
	}
	}
	}


	/**
	* Visit all schemas to do general fixes and handle special cases.
	*
	* @param xmp the metadata object implementation
	* @throws XMPException Thrown if the normalisation fails.
	*/
	private static void touchUpDataModel(XMPMetaImpl xmp) throws XMPException
	{
	// make sure the DC schema is existing, because it might be needed within the normalization
	// if not touched it will be removed by removeEmptySchemas
	XMPNodeUtils.findSchemaNode(xmp.getRoot(), XMPConst.NS_DC, true);

	// Do the special case fixes within each schema.
	for (Iterator it = xmp.getRoot().iterateChildren(); it.hasNext();)
	{
	XMPNode currSchema = (XMPNode) it.next();
	if (XMPConst.NS_DC.equals(currSchema.getName()))
	{
	normalizeDCArrays(currSchema);
	}
	else if (XMPConst.NS_EXIF.equals(currSchema.getName()))
	{
	// Do a special case fix for exif:GPSTimeStamp.
	fixGPSTimeStamp(currSchema);
	XMPNode arrayNode = XMPNodeUtils.findChildNode(currSchema, "exif:UserComment",
	false);
	if (arrayNode != null)
	{
	repairAltText(arrayNode);
	}
	}
	else if (XMPConst.NS_DM.equals(currSchema.getName()))
	{
	// Do a special case migration of xmpDM:copyright to
	// dc:rights['x-default'].
	XMPNode dmCopyright = XMPNodeUtils.findChildNode(currSchema, "xmpDM:copyright",
	false);
	if (dmCopyright != null)
	{
	migrateAudioCopyright(xmp, dmCopyright);
	}
	}
	else if (XMPConst.NS_XMP_RIGHTS.equals(currSchema.getName()))
	{
	XMPNode arrayNode = XMPNodeUtils.findChildNode(currSchema, "xmpRights:UsageTerms",
	false);
	if (arrayNode != null)
	{
	repairAltText(arrayNode);
	}
	}
	}
	}


	/**
	* Undo the denormalization performed by the XMP used in Acrobat 5.<br>
	* If a Dublin Core array had only one item, it was serialized as a simple
	* property. <br>
	* The <code>xml:lang</code> attribute was dropped from an
	* <code>alt-text</code> item if the language was <code>x-default</code>.
	*
	* @param dcSchema the DC schema node
	* @throws XMPException Thrown if normalization fails
	*/
	private static void normalizeDCArrays(XMPNode dcSchema) throws XMPException
	{
	for (int i = 1; i <= dcSchema.getChildrenLength(); i++)
	{
	XMPNode currProp = dcSchema.getChild(i);

	PropertyOptions arrayForm = (PropertyOptions) dcArrayForms.get(currProp.getName());
	if (arrayForm == null)
	{
	continue;
	}
	else if (currProp.getOptions().isSimple())
	{
	// create a new array and add the current property as child,
	// if it was formerly simple
	XMPNode newArray = new XMPNode(currProp.getName(), arrayForm);
	currProp.setName(XMPConst.ARRAY_ITEM_NAME);
	newArray.addChild(currProp);
	dcSchema.replaceChild(i, newArray);

	// fix language alternatives
	if (arrayForm.isArrayAltText() && !currProp.getOptions().getHasLanguage())
	{
	XMPNode newLang = new XMPNode(XMPConst.XML_LANG, XMPConst.X_DEFAULT, null);
	currProp.addQualifier(newLang);
	}
	}
	else
	{
	// clear array options and add corrected array form if it has been an array before
	currProp.getOptions().setOption(
	PropertyOptions.ARRAY \|
	PropertyOptions.ARRAY_ORDERED \|
	PropertyOptions.ARRAY_ALTERNATE \|
	PropertyOptions.ARRAY_ALT_TEXT,
	false);
	currProp.getOptions().mergeWith(arrayForm);

	if (arrayForm.isArrayAltText())
	{
	// applying for "dc:description", "dc:rights", "dc:title"
	repairAltText(currProp);
	}
	}

	}
	}


	/**
	* Make sure that the array is well-formed AltText. Each item must be simple
	* and have an "xml:lang" qualifier. If repairs are needed, keep simple
	* non-empty items by adding the "xml:lang" with value "x-repair".
	* @param arrayNode the property node of the array to repair.
	* @throws XMPException Forwards unexpected exceptions.
	*/
	private static void repairAltText(XMPNode arrayNode) throws XMPException
	{
	if (arrayNode == null \|\|
	!arrayNode.getOptions().isArray())
	{
	// Already OK or not even an array.
	return;
	}

	// fix options
	arrayNode.getOptions().setArrayOrdered(true).setArrayAlternate(true).setArrayAltText(true);

	for (Iterator it = arrayNode.iterateChildren(); it.hasNext();)
	{
	XMPNode currChild = (XMPNode) it.next();
	if (currChild.getOptions().isCompositeProperty())
	{
	// Delete non-simple children.
	it.remove();
	}
	else if (!currChild.getOptions().getHasLanguage())
	{
	String childValue = currChild.getValue();
	if (childValue == null \|\| childValue.length() == 0)
	{
	// Delete empty valued children that have no xml:lang.
	it.remove();
	}
	else
	{
	// Add an xml:lang qualifier with the value "x-repair".
	XMPNode repairLang = new XMPNode(XMPConst.XML_LANG, "x-repair", null);
	currChild.addQualifier(repairLang);
	}
	}
	}
	}


	/**
	* Visit all of the top level nodes looking for aliases. If there is
	* no base, transplant the alias subtree. If there is a base and strict
	* aliasing is on, make sure the alias and base subtrees match.
	*
	* @param tree the root of the metadata tree
	* @param options th parsing options
	* @throws XMPException Forwards XMP errors
	*/
	private static void moveExplicitAliases(XMPNode tree, ParseOptions options)
	throws XMPException
	{
	if (!tree.getHasAliases())
	{
	return;
	}
	tree.setHasAliases(false);

	boolean strictAliasing = options.getStrictAliasing();

	for (Iterator schemaIt = tree.getUnmodifiableChildren().iterator(); schemaIt.hasNext();)
	{
	XMPNode currSchema = (XMPNode) schemaIt.next();
	if (!currSchema.getHasAliases())
	{
	continue;
	}

	for (Iterator propertyIt = currSchema.iterateChildren(); propertyIt.hasNext();)
	{
	XMPNode currProp = (XMPNode) propertyIt.next();

	if (!currProp.isAlias())
	{
	continue;
	}

	currProp.setAlias(false);

	// Find the base path, look for the base schema and root node.
	XMPAliasInfo info = XMPMetaFactory.getSchemaRegistry()
	.findAlias(currProp.getName());
	if (info != null)
	{
	// find or create schema
	XMPNode baseSchema = XMPNodeUtils.findSchemaNode(tree, info
	.getNamespace(), null, true);
	baseSchema.setImplicit(false);

	XMPNode baseNode = XMPNodeUtils
	.findChildNode(baseSchema,
	info.getPrefix() + info.getPropName(), false);
	if (baseNode == null)
	{
	if (info.getAliasForm().isSimple())
	{
	// A top-to-top alias, transplant the property.
	// change the alias property name to the base name
	String qname = info.getPrefix() + info.getPropName();
	currProp.setName(qname);
	baseSchema.addChild(currProp);
	// remove the alias property
	propertyIt.remove();
	}
	else
	{
	// An alias to an array item,
	// create the array and transplant the property.
	baseNode = new XMPNode(info.getPrefix() + info.getPropName(), info
	.getAliasForm().toPropertyOptions());
	baseSchema.addChild(baseNode);
	transplantArrayItemAlias (propertyIt, currProp, baseNode);
	}

	}
	else if (info.getAliasForm().isSimple())
	{
	// The base node does exist and this is a top-to-top alias.
	// Check for conflicts if strict aliasing is on.
	// Remove and delete the alias subtree.
	if (strictAliasing)
	{
	compareAliasedSubtrees (currProp, baseNode, true);
	}

	propertyIt.remove();
	}
	else
	{
	// This is an alias to an array item and the array exists.
	// Look for the aliased item.
	// Then transplant or check & delete as appropriate.

	XMPNode itemNode = null;
	if (info.getAliasForm().isArrayAltText())
	{
	int xdIndex = XMPNodeUtils.lookupLanguageItem(baseNode,
	XMPConst.X_DEFAULT);
	if (xdIndex != -1)
	{
	itemNode = baseNode.getChild(xdIndex);
	}
	}
	else if (baseNode.hasChildren())
	{
	itemNode = baseNode.getChild(1);
	}

	if (itemNode == null)
	{
	transplantArrayItemAlias (propertyIt, currProp, baseNode);
	}
	else
	{
	if (strictAliasing)
	{
	compareAliasedSubtrees (currProp, itemNode, true);
	}

	propertyIt.remove();
	}
	}
	}
	}
	currSchema.setHasAliases(false);
	}
	}


	/**
	* Moves an alias node of array form to another schema into an array
	* @param propertyIt the property iterator of the old schema (used to delete the property)
	* @param childNode the node to be moved
	* @param baseArray the base array for the array item
	* @throws XMPException Forwards XMP errors
	*/
	private static void transplantArrayItemAlias(Iterator propertyIt, XMPNode childNode,
	XMPNode baseArray) throws XMPException
	{
	if (baseArray.getOptions().isArrayAltText())
	{
	if (childNode.getOptions().getHasLanguage())
	{
	throw new XMPException("Alias to x-default already has a language qualifier",
	XMPError.BADXMP);
	}

	XMPNode langQual = new XMPNode(XMPConst.XML_LANG, XMPConst.X_DEFAULT, null);
	childNode.addQualifier(langQual);
	}

	propertyIt.remove();
	childNode.setName(XMPConst.ARRAY_ITEM_NAME);
	baseArray.addChild(childNode);
	}


	/**
	* Fixes the GPS Timestamp in EXIF.
	* @param exifSchema the EXIF schema node
	* @throws XMPException Thrown if the date conversion fails.
	*/
	private static void fixGPSTimeStamp(XMPNode exifSchema)
	throws XMPException
	{
	// Note: if dates are not found the convert-methods throws an exceptions,
	// and this methods returns.
	XMPNode gpsDateTime = XMPNodeUtils.findChildNode(exifSchema, "exif:GPSTimeStamp", false);
	if (gpsDateTime == null)
	{
	return;
	}

	try
	{
	XMPDateTime binGPSStamp;
	XMPDateTime binOtherDate;

	binGPSStamp = XMPUtils.convertToDate(gpsDateTime.getValue());
	if (binGPSStamp.getYear() != 0 \|\|
	binGPSStamp.getMonth() != 0 \|\|
	binGPSStamp.getDay() != 0)
	{
	return;
	}

	XMPNode otherDate = XMPNodeUtils.findChildNode(exifSchema, "exif:DateTimeOriginal",
	false);
	if (otherDate == null)
	{
	otherDate = XMPNodeUtils.findChildNode(exifSchema, "exif:DateTimeDigitized", false);
	}

	binOtherDate = XMPUtils.convertToDate(otherDate.getValue());
	Calendar cal = binGPSStamp.getCalendar();
	cal.set(Calendar.YEAR, binOtherDate.getYear());
	cal.set(Calendar.MONTH, binOtherDate.getMonth());
	cal.set(Calendar.DAY_OF_MONTH, binOtherDate.getDay());
	binGPSStamp = new XMPDateTimeImpl(cal);
	gpsDateTime.setValue(XMPUtils.convertFromDate (binGPSStamp));
	}
	catch (XMPException e)
	{
	// Don't let a missing or bad date stop other things.
	return;
	}
	}



	/**
	* Remove all empty schemas from the metadata tree that were generated during the rdf parsing.
	* @param tree the root of the metadata tree
	*/
	private static void deleteEmptySchemas(XMPNode tree)
	{
	// Delete empty schema nodes. Do this last, other cleanup can make empty
	// schema.

	for (Iterator it = tree.iterateChildren(); it.hasNext();)
	{
	XMPNode schema = (XMPNode) it.next();
	if (!schema.hasChildren())
	{
	it.remove();
	}
	}
	}


	/**
	* The outermost call is special. The names almost certainly differ. The
	* qualifiers (and hence options) will differ for an alias to the x-default
	* item of a langAlt array.
	*
	* @param aliasNode the alias node
	* @param baseNode the base node of the alias
	* @param outerCall marks the outer call of the recursion
	* @throws XMPException Forwards XMP errors
	*/
	private static void compareAliasedSubtrees(XMPNode aliasNode, XMPNode baseNode,
	boolean outerCall) throws XMPException
	{
	if (!aliasNode.getValue().equals(baseNode.getValue()) \|\|
	aliasNode.getChildrenLength() != baseNode.getChildrenLength())
	{
	throw new XMPException("Mismatch between alias and base nodes", XMPError.BADXMP);
	}

	if (
	!outerCall &&
	(!aliasNode.getName().equals(baseNode.getName()) \|\|
	!aliasNode.getOptions().equals(baseNode.getOptions()) \|\|
	aliasNode.getQualifierLength() != baseNode.getQualifierLength())
	)
	{
	throw new XMPException("Mismatch between alias and base nodes",
	XMPError.BADXMP);
	}

	for (Iterator an = aliasNode.iterateChildren(),
	bn = baseNode.iterateChildren();
	an.hasNext() && bn.hasNext();)
	{
	XMPNode aliasChild = (XMPNode) an.next();
	XMPNode baseChild = (XMPNode) bn.next();
	compareAliasedSubtrees (aliasChild, baseChild, false);
	}


	for (Iterator an = aliasNode.iterateQualifier(),
	bn = baseNode.iterateQualifier();
	an.hasNext() && bn.hasNext();)
	{
	XMPNode aliasQual = (XMPNode) an.next();
	XMPNode baseQual = (XMPNode) bn.next();
	compareAliasedSubtrees (aliasQual, baseQual, false);
	}
	}


	/**
	* The initial support for WAV files mapped a legacy ID3 audio copyright
	* into a new xmpDM:copyright property. This is special case code to migrate
	* that into dc:rights['x-default']. The rules:
	*
	* <pre>
	* 1. If there is no dc:rights array, or an empty array -
	* Create one with dc:rights['x-default'] set from double linefeed and xmpDM:copyright.
	*
	* 2. If there is a dc:rights array but it has no x-default item -
	* Create an x-default item as a copy of the first item then apply rule #3.
	*
	* 3. If there is a dc:rights array with an x-default item,
	* Look for a double linefeed in the value.
	* A. If no double linefeed, compare the x-default value to the xmpDM:copyright value.
	* A1. If they match then leave the x-default value alone.
	* A2. Otherwise, append a double linefeed and
	* the xmpDM:copyright value to the x-default value.
	* B. If there is a double linefeed, compare the trailing text to the xmpDM:copyright value.
	* B1. If they match then leave the x-default value alone.
	* B2. Otherwise, replace the trailing x-default text with the xmpDM:copyright value.
	*
	* 4. In all cases, delete the xmpDM:copyright property.
	* </pre>
	*
	* @param xmp the metadata object
	* @param dmCopyright the "dm:copyright"-property
	*/
	private static void migrateAudioCopyright (XMPMeta xmp, XMPNode dmCopyright)
	{
	try
	{
	XMPNode dcSchema = XMPNodeUtils.findSchemaNode(
	((XMPMetaImpl) xmp).getRoot(), XMPConst.NS_DC, true);

	String dmValue = dmCopyright.getValue();
	String doubleLF = "\n\n";

	XMPNode dcRightsArray = XMPNodeUtils.findChildNode (dcSchema, "dc:rights", false);

	if (dcRightsArray == null \|\| !dcRightsArray.hasChildren())
	{
	// 1. No dc:rights array, create from double linefeed and xmpDM:copyright.
	dmValue = doubleLF + dmValue;
	xmp.setLocalizedText(XMPConst.NS_DC, "rights", "", XMPConst.X_DEFAULT, dmValue,
	null);
	}
	else
	{
	int xdIndex = XMPNodeUtils.lookupLanguageItem(dcRightsArray, XMPConst.X_DEFAULT);

	if (xdIndex < 0)
	{
	// 2. No x-default item, create from the first item.
	String firstValue = dcRightsArray.getChild(1).getValue();
	xmp.setLocalizedText (XMPConst.NS_DC, "rights", "", XMPConst.X_DEFAULT,
	firstValue, null);
	xdIndex = XMPNodeUtils.lookupLanguageItem(dcRightsArray, XMPConst.X_DEFAULT);
	}

	// 3. Look for a double linefeed in the x-default value.
	XMPNode defaultNode = dcRightsArray.getChild(xdIndex);
	String defaultValue = defaultNode.getValue();
	int lfPos = defaultValue.indexOf(doubleLF);

	if (lfPos < 0)
	{
	// 3A. No double LF, compare whole values.
	if (!dmValue.equals(defaultValue))
	{
	// 3A2. Append the xmpDM:copyright to the x-default
	// item.
	defaultNode.setValue(defaultValue + doubleLF + dmValue);
	}
	}
	else
	{
	// 3B. Has double LF, compare the tail.
	if (!defaultValue.substring(lfPos + 2).equals(dmValue))
	{
	// 3B2. Replace the x-default tail.
	defaultNode.setValue(defaultValue.substring(0, lfPos + 2) + dmValue);
	}
	}

	}

	// 4. Get rid of the xmpDM:copyright.
	dmCopyright.getParent().removeChild(dmCopyright);
	}
	catch (XMPException e)
	{
	// Don't let failures (like a bad dc:rights form) stop other
	// cleanup.
	}
	}


	/**
	* Initializes the map that contains the known arrays, that are fixed by
	* {@link XMPNormalizer#normalizeDCArrays(XMPNode)}.
	*/
	private static void initDCArrays()
	{
	dcArrayForms = new HashMap();

	// Properties supposed to be a "Bag".
	PropertyOptions bagForm = new PropertyOptions();
	bagForm.setArray(true);
	dcArrayForms.put("dc:contributor", bagForm);
	dcArrayForms.put("dc:language", bagForm);
	dcArrayForms.put("dc:publisher", bagForm);
	dcArrayForms.put("dc:relation", bagForm);
	dcArrayForms.put("dc:subject", bagForm);
	dcArrayForms.put("dc:type", bagForm);

	// Properties supposed to be a "Seq".
	PropertyOptions seqForm = new PropertyOptions();
	seqForm.setArray(true);
	seqForm.setArrayOrdered(true);
	dcArrayForms.put("dc:creator", seqForm);
	dcArrayForms.put("dc:date", seqForm);

	// Properties supposed to be an "Alt" in alternative-text form.
	PropertyOptions altTextForm = new PropertyOptions();
	altTextForm.setArray(true);
	altTextForm.setArrayOrdered(true);
	altTextForm.setArrayAlternate(true);
	altTextForm.setArrayAltText(true);
	dcArrayForms.put("dc:description", altTextForm);
	dcArrayForms.put("dc:rights", altTextForm);
	dcArrayForms.put("dc:title", altTextForm);
	}
	}