/*******************************************************************************
 * Copyright (c) 2006, 2009 Oracle. All rights reserved.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0, which accompanies this distribution
 * and is available at http://www.eclipse.org/legal/epl-v10.html.
 * 
 * Contributors:
 *     Oracle - initial API and implementation
 ******************************************************************************/
package org.eclipse.jpt.core.internal.context.java;

import java.util.Iterator;
import java.util.List;

import org.eclipse.core.runtime.content.IContentType;
import org.eclipse.jdt.core.dom.CompilationUnit;
import org.eclipse.jdt.core.dom.Modifier;
import org.eclipse.jpt.core.JpaStructureNode;
import org.eclipse.jpt.core.MappingKeys;
import org.eclipse.jpt.core.context.AccessType;
import org.eclipse.jpt.core.context.Embeddable;
import org.eclipse.jpt.core.context.PersistentType;
import org.eclipse.jpt.core.context.TypeMapping;
import org.eclipse.jpt.core.context.java.JavaAttributeMapping;
import org.eclipse.jpt.core.context.java.JavaPersistentAttribute;
import org.eclipse.jpt.core.context.java.JavaStructureNodes;
import org.eclipse.jpt.core.internal.validation.DefaultJpaValidationMessages;
import org.eclipse.jpt.core.internal.validation.JpaValidationMessages;
import org.eclipse.jpt.core.resource.java.Annotation;
import org.eclipse.jpt.core.resource.java.JavaResourcePersistentAttribute;
import org.eclipse.jpt.core.utility.TextRange;
import org.eclipse.jpt.utility.Filter;
import org.eclipse.jpt.utility.internal.ClassTools;
import org.eclipse.jpt.utility.internal.CollectionTools;
import org.eclipse.jpt.utility.internal.HashBag;
import org.eclipse.jpt.utility.internal.iterators.EmptyIterator;
import org.eclipse.wst.validation.internal.provisional.core.IMessage;
import org.eclipse.wst.validation.internal.provisional.core.IReporter;

/**
 * common state/behavior between Generic and EclipseLink persistent attributes
 */
public abstract class AbstractJavaPersistentAttribute
	extends AbstractJavaJpaContextNode
	implements JavaPersistentAttribute
{
	protected String name;

	protected JavaAttributeMapping defaultMapping;

	protected JavaAttributeMapping specifiedMapping;

	protected JavaResourcePersistentAttribute resourcePersistentAttribute;


	protected AbstractJavaPersistentAttribute(PersistentType parent, JavaResourcePersistentAttribute resourcePersistentAttribute) {
		super(parent);
		this.resourcePersistentAttribute = resourcePersistentAttribute;
		this.name = this.buildName();
		this.defaultMapping = this.buildDefaultMapping();
		this.specifiedMapping = this.buildJavaAttributeMappingFromAnnotation(this.getJavaMappingAnnotationName());
	}


	// ********** JpaStructureNode implementation **********

	public String getId() {
		return JavaStructureNodes.PERSISTENT_ATTRIBUTE_ID;
	}

	public IContentType getContentType() {
		return this.getPersistentType().getContentType();
	}

	public JpaStructureNode getStructureNode(int textOffset) {
		return this;
	}

	public TextRange getSelectionTextRange() {
		return this.getSelectionTextRange(this.buildASTRoot());
	}

	protected TextRange getSelectionTextRange(CompilationUnit astRoot) {
		return this.resourcePersistentAttribute.getNameTextRange(astRoot);
	}

	protected CompilationUnit buildASTRoot() {
		return this.resourcePersistentAttribute.getJavaResourceCompilationUnit().buildASTRoot();
	}

	public void dispose() {
		//nothing to dispose
	}


	// ********** AccessHolder implementation **********

	public AccessType getAccess() {
		AccessType access = this.getSpecifiedAccess();
		return (access != null) ? access : this.getDefaultAccess();
	}

	public AccessType getDefaultAccess() {
		return this.resourcePersistentAttribute.isField() ? AccessType.FIELD : AccessType.PROPERTY;
	}


	// ********** [Java]PersistentAttribute implementation **********

	public JavaResourcePersistentAttribute getResourcePersistentAttribute() {
		return this.resourcePersistentAttribute;
	}

	public PersistentType getPersistentType() {
		return this.getParent();
	}

	public TypeMapping getTypeMapping() {
		return this.getPersistentType().getMapping();
	}

	public String getPrimaryKeyColumnName() {
		return this.getMapping().getPrimaryKeyColumnName();
	}

	public boolean isOverridableAttribute() {
		return this.getMapping().isOverridableAttributeMapping();
	}

	public boolean isOverridableAssociation() {
		return this.getMapping().isOverridableAssociationMapping();
	}

	public boolean isIdAttribute() {
		return this.getMapping().isIdMapping();
	}

	public boolean isVirtual() {
		return false;
	}

	public boolean contains(int offset, CompilationUnit astRoot) {
		TextRange fullTextRange = this.getFullTextRange(astRoot);
		// 'fullTextRange' will be null if the attribute no longer exists in the java;
		// the context model can be out of synch with the resource model
		// when a selection event occurs before the context model has a
		// chance to synch with the resource model via the update thread
		return (fullTextRange == null) ? false : fullTextRange.includes(offset);
	}

	protected TextRange getFullTextRange(CompilationUnit astRoot) {
		return this.resourcePersistentAttribute.getTextRange(astRoot);
	}

	public Embeddable getEmbeddable() {
		String typeName = this.resourcePersistentAttribute.getTypeName();
		return (typeName == null) ? null : this.getPersistenceUnit().getEmbeddable(typeName);
	}

	public boolean isField() {
		return this.resourcePersistentAttribute.isField();
	}

	public boolean isProperty() {
		return this.resourcePersistentAttribute.isProperty();
	}

	public boolean isPublic() {
		return Modifier.isPublic(this.resourcePersistentAttribute.getModifiers());
	}

	public boolean isFinal() {
		return Modifier.isFinal(this.resourcePersistentAttribute.getModifiers());
	}

	// ***** Basic defaults
	/**
	 * From the JPA spec, when the basic mapping applies:
	 * If the type of the attribute (field or property) is one of the following
	 * it must be mapped as @Basic:
	 *     byte[]
	 *     java.lang.Byte[]
	 *     char[]
	 *     java.lang.Character[]
	 *     primitive types (except 'void')
	 *     primitive wrappers (except 'java.lang.Void')
	 *     java.lang.String
	 *     java.math.BigInteger
	 *     java.math.BigDecimal
	 *     java.util.Date
	 *     java.util.Calendar
	 *     java.sql.Date
	 *     java.sql.Time
	 *     java.sql.Timestamp
	 *     enums
	 *     any other type that implements java.io.Serializable
	 */
	public boolean typeIsBasic() {
		// 'typeName' may include array brackets but not generic type arguments
		String typeName = this.resourcePersistentAttribute.getTypeName();
		if (typeName == null) {
			return false;
		}

		int arrayDepth = ClassTools.arrayDepthForTypeDeclaration(typeName);
		if (arrayDepth > 1) {
			return false;  // multi-dimensional arrays are not supported
		}

		if (arrayDepth == 1) {
			String elementTypeName = ClassTools.elementTypeNameForTypeDeclaration(typeName, 1);
			return this.elementTypeIsValidForBasicArray(elementTypeName);
		}

		// arrayDepth == 0
		if (ClassTools.classNamedIsVariablePrimitive(typeName)) {
			return true;  // any primitive but 'void'
		}
		if (ClassTools.classNamedIsVariablePrimitiveWrapperClass(typeName)) {
			return true;  // any primitive wrapper but 'java.lang.Void'
		}
		if (this.typeIsOtherValidBasicType(typeName)) {
			return true;
		}
		if (this.resourcePersistentAttribute.typeIsEnum()) {
			return true;
		}
		if (this.resourcePersistentAttribute.typeIsSubTypeOf(SERIALIZABLE_TYPE_NAME)) {
			return true;
		}
		return false;
	}

	/**
	 * Return whether the specified type is a valid element type for
	 * a one-dimensional array that can default to a Basic mapping:
	 *     byte
	 *     char
	 *     java.lang.Byte
	 *     java.lang.Character
	 */
	protected boolean elementTypeIsValidForBasicArray(String elementTypeName) {
		return CollectionTools.contains(VALID_BASIC_ARRAY_ELEMENT_TYPE_NAMES, elementTypeName);
	}

	protected static final String[] VALID_BASIC_ARRAY_ELEMENT_TYPE_NAMES = {
		byte.class.getName(),
		char.class.getName(),
		java.lang.Byte.class.getName(),
		java.lang.Character.class.getName()
	};

	/**
	 * Return whether the specified type is among the various "other" types
	 * that can default to a Basic mapping.
	 */
	protected boolean typeIsOtherValidBasicType(String typeName) {
		return CollectionTools.contains(OTHER_VALID_BASIC_TYPE_NAMES, typeName);
	}

	protected static final String[] OTHER_VALID_BASIC_TYPE_NAMES = {
		java.lang.String.class.getName(),
		java.math.BigInteger.class.getName(),
		java.math.BigDecimal.class.getName(),
		java.util.Date.class.getName(),
		java.util.Calendar.class.getName(),
		java.sql.Date.class.getName(),
		java.sql.Time.class.getName(),
		java.sql.Timestamp.class.getName(),
	};

	protected static final String SERIALIZABLE_TYPE_NAME = java.io.Serializable.class.getName();

	// ***** reference entities
	public String getSingleReferenceEntityTypeName() {
		return this.buildSingleReferenceEntityTypeName(this.resourcePersistentAttribute.getTypeName());
	}

	public String getMultiReferenceEntityTypeName() {
		// 'typeName' may include array brackets but not generic type arguments
		String typeName = this.resourcePersistentAttribute.getTypeName();
		if (typeName == null) {
			return null;
		}
		if (ClassTools.arrayDepthForTypeDeclaration(typeName) != 0) {
			return null;  // arrays cannot hold entities
		}
		switch (this.resourcePersistentAttribute.typeTypeArgumentNamesSize()) {
			case 0:
				return null;
			case 1:
				return this.typeIsCollection(typeName) ? this.resourcePersistentAttribute.getTypeTypeArgumentName(0) : null;
			case 2:
				return this.typeIsMap(typeName) ? this.resourcePersistentAttribute.getTypeTypeArgumentName(1) : null;
			default:
				return null;
		}
	}

	/**
	 * 'typeName' may include array brackets ("[]")
	 * but not generic type arguments (e.g. "<java.lang.String>")
	 */
	protected String buildSingleReferenceEntityTypeName(String typeName) {
		if (typeName == null) {
			return null;
		}
		if (ClassTools.arrayDepthForTypeDeclaration(typeName) != 0) {
			return null;  // arrays cannot be entities
		}
		if (this.typeIsContainer(typeName)) {
			return null;  // "containers" cannot be entities
		}
		return typeName;
	}

	/**
	 * return whether the specified type is one of the collection
	 * types allowed by the JPA spec
	 */
	protected boolean typeIsCollection(String typeName) {
		return CollectionTools.contains(COLLECTION_TYPE_NAMES, typeName);
	}
	protected static final String[] COLLECTION_TYPE_NAMES = {
		java.util.Collection.class.getName(),
		java.util.Set.class.getName(),
		java.util.List.class.getName()
	};

	/**
	 * return whether the specified type is one of the map
	 * types allowed by the JPA spec
	 */
	protected boolean typeIsMap(String typeName) {
		return CollectionTools.contains(MAP_TYPE_NAMES, typeName);
	}
	protected static final String[] MAP_TYPE_NAMES = {
		java.util.Map.class.getName()
	};

	/**
	 * return whether the specified type is one of the container
	 * types allowed by the JPA spec
	 */
	protected boolean typeIsContainer(String typeName) {
		return CollectionTools.contains(CONTAINER_TYPE_NAMES, typeName);
	}
	protected static final String[] CONTAINER_TYPE_NAMES = CollectionTools.concatenate(
		COLLECTION_TYPE_NAMES,
		MAP_TYPE_NAMES
	);

	// ***** name
	public String getName() {
		return this.name;
	}

	protected void setName(String name) {
		String old = this.name;
		this.name = name;
		this.firePropertyChanged(NAME_PROPERTY, old, name);
	}

	protected String buildName() {
		return this.resourcePersistentAttribute.getName();
	}

	// ***** mapping
	public JavaAttributeMapping getMapping() {
		return (this.specifiedMapping != null) ? this.specifiedMapping : this.defaultMapping;
	}

	public String getMappingKey() {
		return this.getMapping().getKey();
	}

	// ***** default mapping
	public JavaAttributeMapping getDefaultMapping() {
		return this.defaultMapping;
	}

	/**
	 * clients do not set the "default" mapping
	 */
	protected void setDefaultMapping(JavaAttributeMapping defaultMapping) {
		JavaAttributeMapping old = this.defaultMapping;
		this.defaultMapping = defaultMapping;
		this.firePropertyChanged(DEFAULT_MAPPING_PROPERTY, old, defaultMapping);
	}

	protected JavaAttributeMapping buildDefaultMapping() {
		JavaAttributeMapping mapping = this.getJpaPlatform().buildDefaultJavaAttributeMapping(this);
		Annotation annotation = this.resourcePersistentAttribute.getNullMappingAnnotation(mapping.getAnnotationName());
		mapping.initialize(annotation);
		return mapping;
	}

	/**
	 * return null if there is no "default" mapping for the attribute
	 */
	public String getDefaultMappingKey() {
		return this.defaultMapping.getKey();
	}

	/**
	 * the mapping might be "default", but it still might be a "null" mapping...
	 */
	public boolean mappingIsDefault(JavaAttributeMapping mapping) {
		return this.defaultMapping == mapping;
	}

	// ***** specified mapping
	public JavaAttributeMapping getSpecifiedMapping() {
		return this.specifiedMapping;
	}

	/**
	 * clients do not set the "specified" mapping;
	 * @see #setSpecifiedMappingKey(String)
	 */
	protected void setSpecifiedMapping(JavaAttributeMapping specifiedMapping) {
		JavaAttributeMapping old = this.specifiedMapping;
		this.specifiedMapping = specifiedMapping;
		this.firePropertyChanged(SPECIFIED_MAPPING_PROPERTY, old, specifiedMapping);
	}

	/**
	 * return null if there is no "specified" mapping for the attribute
	 */
	protected String getSpecifiedMappingKey() {
		return (this.specifiedMapping == null) ? null : this.specifiedMapping.getKey();
	}

	// TODO support morphing mappings, i.e. copying common settings over
	// to the new mapping; this can't be done in the same was as XmlAttributeMapping
	// since we don't know all the possible mapping types
	public void setSpecifiedMappingKey(String key) {
		if (key == this.getSpecifiedMappingKey()) {
			return;
		}
		JavaAttributeMapping oldMapping = this.specifiedMapping;
		JavaAttributeMapping newMapping = this.buildMappingFromMappingKey(key);

		this.specifiedMapping = newMapping;
		this.resourcePersistentAttribute.setMappingAnnotation((newMapping == null) ? null : newMapping.getAnnotationName());
		this.firePropertyChanged(SPECIFIED_MAPPING_PROPERTY, oldMapping, newMapping);

		// remove "supporting annotations" that do not "support" to the new mapping
		if (oldMapping != null) {
			HashBag<String> annotationsToRemove = CollectionTools.collection(oldMapping.supportingAnnotationNames());
			CollectionTools.removeAll(annotationsToRemove, this.supportingAnnotationNames());
			for (String annotationName : annotationsToRemove) {
				this.resourcePersistentAttribute.removeSupportingAnnotation(annotationName);
			}
		}
	}

	protected JavaAttributeMapping buildMappingFromMappingKey(String key) {
		if (key == MappingKeys.NULL_ATTRIBUTE_MAPPING_KEY) {
			return null;
		}
		JavaAttributeMapping mapping = this.getJpaPlatform().buildJavaAttributeMappingFromMappingKey(key, this);
		//no mapping.initialize(JavaResourcePersistentAttribute) call here
		//we do not yet have a mapping annotation so we can't call initialize
		return mapping;
	}

	protected Iterator<String> supportingAnnotationNames() {
		JavaAttributeMapping mapping = this.getMapping();
		return (mapping != null) ? mapping.supportingAnnotationNames() : EmptyIterator.<String>instance();
	}


	// ********** updating **********

	public void update() {
		this.setName(this.buildName());
		this.updateDefaultMapping();
		this.updateSpecifiedMapping();
	}

	protected void updateDefaultMapping() {
		String defaultMappingKey = this.getJpaPlatform().getDefaultJavaAttributeMappingKey(this);
		if (this.defaultMapping.getKey() == defaultMappingKey) {
			this.defaultMapping.update(this.resourcePersistentAttribute.getNullMappingAnnotation(this.defaultMapping.getAnnotationName()));
		} else {
			JavaAttributeMapping old = this.defaultMapping;
			this.defaultMapping = this.buildDefaultMapping();
			this.firePropertyChanged(DEFAULT_MAPPING_PROPERTY, old, this.defaultMapping);
		}
	}

	protected void updateSpecifiedMapping() {
		String javaMappingAnnotationName = this.getJavaMappingAnnotationName();
		if (javaMappingAnnotationName == this.getSpecifiedMappingAnnotationName()) {
			if (this.specifiedMapping != null) {
				this.specifiedMapping.update(this.resourcePersistentAttribute.getMappingAnnotation(javaMappingAnnotationName));
			}
		} else {
			this.setSpecifiedMapping(this.buildJavaAttributeMappingFromAnnotation(javaMappingAnnotationName));
		}
	}

	protected String getJavaMappingAnnotationName() {
		Annotation mappingAnnotation = this.resourcePersistentAttribute.getMappingAnnotation();
		return (mappingAnnotation == null) ? null : mappingAnnotation.getAnnotationName();
	}

	protected String getSpecifiedMappingAnnotationName() {
		return (this.specifiedMapping == null) ? null : this.specifiedMapping.getAnnotationName();
	}

	protected JavaAttributeMapping buildJavaAttributeMappingFromAnnotation(String annotationName) {
		if (annotationName == null) {
			return null;
		}
		JavaAttributeMapping mapping = getJpaPlatform().buildJavaAttributeMappingFromAnnotation(annotationName, this);
		mapping.initialize(this.resourcePersistentAttribute.getMappingAnnotation(annotationName));
		return mapping;
	}


	// ********** validation **********

	public TextRange getValidationTextRange(CompilationUnit astRoot) {
		return this.getSelectionTextRange(astRoot);
	}

	@Override
	public void validate(List<IMessage> messages, IReporter reporter, CompilationUnit astRoot) {
		super.validate(messages, reporter, astRoot);

		this.validateModifiers(messages, astRoot);

		if (this.specifiedMapping != null) {
			this.specifiedMapping.validate(messages, reporter, astRoot);
		}
		else if (this.defaultMapping != null) {
			this.defaultMapping.validate(messages, reporter, astRoot);
		}
	}


	protected void validateModifiers(List<IMessage> messages, CompilationUnit astRoot) {
		if (this.getMappingKey() == MappingKeys.TRANSIENT_ATTRIBUTE_MAPPING_KEY) {
			return;
		}

		if (this.isField()) {
			if (this.isFinal()) {
				messages.add(this.buildAttributeMessage(JpaValidationMessages.PERSISTENT_ATTRIBUTE_FINAL_FIELD, astRoot));
			}
			if (this.isPublic()) {
				messages.add(this.buildAttributeMessage(JpaValidationMessages.PERSISTENT_ATTRIBUTE_PUBLIC_FIELD, astRoot));
			}
		}
	}

	protected IMessage buildAttributeMessage(String msgID, CompilationUnit astRoot) {
		return DefaultJpaValidationMessages.buildMessage(
				IMessage.HIGH_SEVERITY,
				msgID,
				new String[] {getName()},
				this,
				this.getValidationTextRange(astRoot)
			);
	}


	// ********** Java completion proposals **********

	@Override
	public Iterator<String> javaCompletionProposals(int pos, Filter<String> filter, CompilationUnit astRoot) {
		Iterator<String> result = super.javaCompletionProposals(pos, filter, astRoot);
		if (result != null) {
			return result;
		}
		return this.getMapping().javaCompletionProposals(pos, filter, astRoot);
	}


	// ********** misc overrides **********

	@Override
	public PersistentType getParent() {
		return (PersistentType) super.getParent();
	}

	@Override
	public void toString(StringBuilder sb) {
		super.toString(sb);
		sb.append(this.name);
	}

}