/*
 Wotonomy: OpenStep design patterns for pure Java applications.
 Copyright (C) 2001 Michael Powers

 This library is free software; you can redistribute it and/or
 modify it under the terms of the GNU Lesser General Public
 License as published by the Free Software Foundation; either
 version 2.1 of the License, or (at your option) any later version.

 This library is distributed in the hope that it will be useful,
 but WITHOUT ANY WARRANTY; without even the implied warranty of
 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 Lesser General Public License for more details.

 You should have received a copy of the GNU Lesser General Public
 License along with this library; if not, see http://www.gnu.org
 */
package net.wotonomy.access;

import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.util.Map;

import net.wotonomy.control.EOAndQualifier;
import net.wotonomy.control.EOClassDescription;
import net.wotonomy.control.EOFetchSpecification;
import net.wotonomy.control.EOGenericRecord;
import net.wotonomy.control.EOGlobalID;
import net.wotonomy.control.EOIntegralKeyGlobalID;
import net.wotonomy.control.EOKeyGlobalID;
import net.wotonomy.control.EOKeyValueArchiver;
import net.wotonomy.control.EOKeyValueQualifier;
import net.wotonomy.control.EOKeyValueUnarchiver;
import net.wotonomy.control.EOQualifier;
import net.wotonomy.control.EOVectorKeyGlobalID;
import net.wotonomy.foundation.NSArray;
import net.wotonomy.foundation.NSDictionary;
import net.wotonomy.foundation.NSKeyValueCoding;
import net.wotonomy.foundation.NSMutableArray;
import net.wotonomy.foundation.NSMutableDictionary;
import net.wotonomy.foundation.NSPropertyListSerialization;

/**
* An EOEntity is a mapping between a Java class and a database table or view.
* It indicates which attributes should be fetched from the table/view, what
* attributes are part of the primary key, what class the entity should map to.
*
* @author ezamudio@nasoft.com
* @author $Author: cgruber $
* @version $Revision: 894 $
*/
public class EOEntity implements EOPropertyListEncoding {

	protected NSMutableDictionary _attributes = new NSMutableDictionary();
	protected NSMutableDictionary _relations = new NSMutableDictionary();
	private NSMutableArray _classPropertyNames = new NSMutableArray();
	private NSMutableArray _classProperties = new NSMutableArray();
	private NSMutableArray _classPropertyAttributes = new NSMutableArray();
	private NSMutableArray _classPropertyManyRelationships = new NSMutableArray();
	private NSMutableArray _classPropertyOneRelationships = new NSMutableArray();
	protected NSArray _pkAttributes = NSArray.EmptyArray;
	protected NSArray _pkAttributeNames = NSArray.EmptyArray;
	protected NSMutableDictionary _fetchSpecs = new NSMutableDictionary();
	protected NSMutableArray _lockingAttributes = new NSMutableArray();

	protected String _className;
	protected String _name;
	protected String _externalName;
	protected boolean _isAbstract;
	protected boolean _isReadOnly;
	protected EOModel _model;
	protected NSDictionary _userInfo;
	protected NSDictionary _internalInfo;
	private boolean _loadedFetchSpecs;

	public EOEntity() {
		super();
	}

	public EOEntity(NSDictionary dict, Object obj) {
		super();
		_model = (EOModel)obj;
		setName((String)dict.objectForKey("name"));
		setExternalName((String)dict.objectForKey("externalName"));
		setClassName((String)dict.objectForKey("className"));
		if (dict.objectForKey("internalInfo") != null)
			_internalInfo = (NSDictionary)dict.objectForKey("internalInfo");
		if (dict.objectForKey("userInfo") != null)
			_userInfo = (NSDictionary)dict.objectForKey("userInfo");

		//Read the attributes
		NSArray atr = (NSArray)dict.objectForKey("attributes");
		for (int i = 0; i < atr.count(); i++) {
			NSDictionary d = (NSDictionary)atr.objectAtIndex(i);
			EOAttribute atrib = new EOAttribute(d, this);
			addAttribute(atrib);
		}

		//Set the primary key
		atr = (NSArray)dict.objectForKey("primaryKeyAttributes");
		NSMutableArray pka = new NSMutableArray();
		for (int i = 0; i < atr.count(); i++) {
			EOAttribute a = attributeNamed((String)atr.objectAtIndex(i));
			pka.addObject(a);
		}
		_pkAttributes = new NSArray(pka);
		_pkAttributeNames = atr;

		//attributes used for locking
		_lockingAttributes.removeAllObjects();
		atr = (NSArray)dict.objectForKey("attributesUsedForLocking");
		for (int i = 0; i < atr.count(); i++) {
			String x = (String)atr.objectAtIndex(i);
			EOAttribute a = attributeNamed(x);
			_lockingAttributes.addObject(a);
		}

		//class properties
		atr = (NSArray)dict.objectForKey("classProperties");
		if (atr != null) {
			for (int i = 0; i < atr.count(); i++)
				if (!_classPropertyNames.containsObject((atr.objectAtIndex(i))))
					_classPropertyNames.addObject(atr.objectAtIndex(i));
		}

		//Read the relationships
		atr = (NSArray)dict.objectForKey("relationships");
		if (atr != null) {
			for (int i = 0; i < atr.count(); i++) {
				NSDictionary d = (NSDictionary)atr.objectAtIndex(i);
				EORelationship rel = new EORelationship(d, this);
				addRelationship(rel);
			}
		}
	}

	public void addAttribute(EOAttribute atr) {
		if (atr.name() == null)
			throw new IllegalArgumentException("Cannot add an unnamed attribute to an entity.");
		if (_attributes.objectForKey(atr.name()) != null)
			throw new IllegalArgumentException("Entity " + name() + " already has an attribute named " + atr.name());
		_attributes.setObjectForKey(atr, atr.name());
		atr.setEntity(this);
		_lockingAttributes.addObject(atr);
		_classProperties.addObject(atr);
		_classPropertyNames.addObject(atr.name());
		_classPropertyAttributes.addObject(atr);
	}

	public void removeAttribute(EOAttribute atr) {
		_attributes.removeObjectForKey(atr.name());
		atr.setEntity(null);
		_classProperties.removeObject(atr);
		_classPropertyNames.removeObject(atr.name());
		_classPropertyAttributes.removeObject(atr);
	}

	public void addFetchSpecification(EOFetchSpecification fspec, String name) {
		loadFetchSpecifications();
		if (_fetchSpecs.objectForKey(name) != null)
			throw new IllegalArgumentException("Entity " + name() + " already has a fetch specification named " + name);
		_fetchSpecs.setObjectForKey(fspec, name);
	}

	public void removeFetchSpecificationNamed(String name) {
		_fetchSpecs.removeObjectForKey(name);
	}

	public EOFetchSpecification fetchSpecificationNamed(String name) {
		loadFetchSpecifications();
		return (EOFetchSpecification)_fetchSpecs.objectForKey(name);
	}

	public NSArray fetchSpecificationNames() {
		loadFetchSpecifications();
		return _fetchSpecs.allKeys();
	}

	/** Loads fetch specifications from the .fspec file,
	 * if one exists.
	 */
	private void loadFetchSpecifications() {
		if (_loadedFetchSpecs)
			return;
		_loadedFetchSpecs = true;
		if (model().path() == null)
			return;
		File f = new File(model().path());
		//Read the fetch specification file, if it exists
		f = new File(f, name() + ".fspec");
		if (!f.exists())
			return;
		NSDictionary fdict = null;
		String x = null;
		try {
			FileInputStream fin = new FileInputStream(f);
			byte[] b = new byte[fin.available()];
			fin.read(b);
			fin.close();
			x = new String(b);
		} catch (IOException ex) {
			throw new IllegalArgumentException("Cannot read file " + f);
		}
		fdict = NSPropertyListSerialization.dictionaryForString(x);
		if (fdict == null)
			throw new IllegalArgumentException("Cannot read dictionary from " + f);
		NSArray keys = fdict.allKeys();

		//Unarchive the fetch specification
		EOKeyValueUnarchiver unarch = new EOKeyValueUnarchiver(fdict);
		for (int i = 0; i < keys.count(); i++) {
			String k = (String)keys.objectAtIndex(i);
			EOFetchSpecification fs = (EOFetchSpecification)unarch.decodeObjectForKey(k);
			if (fs != null)
				_fetchSpecs.setObjectForKey(fs, k);
		}
	}

	public NSArray attributes() {
		return _attributes.allValues();
	}

	public EOAttribute attributeNamed(String name) {
		return (EOAttribute)_attributes.objectForKey(name);
	}

	public NSArray flattenedAttributes() {
		return null;
	}

	public void setClassName(String name) {
		_className = name;
	}
	public String className() {
		return _className;
	}

	public void setName(String name) {
		_name = name;
	}
	public String name() {
		return _name;
	}

	public void setExternalName(String name) {
		_externalName = name;
	}
	public String externalName() {
		return _externalName;
	}

	public void addRelationship(EORelationship rel) {
		if (rel.name() == null)
			throw new IllegalArgumentException("Cannot add an unnamed relationship to an entity.");
		if (_relations.objectForKey(rel.name()) != null)
			throw new IllegalArgumentException("Entity " + name() + " already has a relationship named " + rel.name());
		if (_attributes.objectForKey(rel.name()) != null)
			throw new IllegalArgumentException("Entity " + name() + " has an attribute named " + rel.name());
		_relations.setObjectForKey(rel, rel.name());
		_classProperties.addObject(rel);
		_classPropertyNames.addObject(rel.name());
		if (rel.isToMany())
			_classPropertyManyRelationships.addObject(rel);
		else
			_classPropertyOneRelationships.addObject(rel);
	}

	public void removeRelationship(EORelationship rel) {
		_relations.removeObjectForKey(rel.name());
		_classProperties.removeObject(rel);
		_classPropertyNames.removeObject(rel.name());
		_classPropertyManyRelationships.removeObject(rel);
		_classPropertyOneRelationships.removeObject(rel);
	}

	/** Returns the relationships from this entity to other entities.
	 * @return An array of the relationships of this entity.
	 */
	public NSArray relationships() {
		return _relations.allValues();
	}

	public EORelationship relationshipNamed(String name) {
		return (EORelationship)_relations.objectForKey(name);
	}
	public EOModel model() {
		return _model;
	}

	public void setPrimaryKeyAtributes(NSArray pk) {
		_pkAttributes = pk;
	}
	public NSArray primaryKeyAttributes() {
		return _pkAttributes;
	}

	public NSArray primaryKeyAttributeNames() {
		if (_pkAttributeNames.count() != _pkAttributes.count()) {
			NSMutableArray arr = new NSMutableArray();
			for (int i = 0; i < _pkAttributes.count(); i++) {
				EOAttribute a = (EOAttribute)_pkAttributes.objectAtIndex(i);
				arr.addObject(a.name());
			}
			_pkAttributeNames = new NSArray(arr);
		}
		return _pkAttributeNames;
	}

	public boolean hasSimplePrimaryKey() {
		return _pkAttributes.count() == 1;
	}

	public boolean isValidPrimaryKeyAttribute(EOAttribute attr) {
		return !attr.allowsNull();
	}

	public void setAttributesUsedForLocking(NSArray value) {
		_lockingAttributes.removeAllObjects();
		_lockingAttributes.addObjectsFromArray(value);
	}
	public NSArray attributesUsedForLocking() {
		return new NSArray(_lockingAttributes);
	}

	public void setClassProperties(NSArray value) {
		_classProperties.removeAllObjects();
		_classProperties.addObjectsFromArray(value);
		_classPropertyNames.removeAllObjects();
		_classPropertyAttributes.removeAllObjects();
		_classPropertyOneRelationships.removeAllObjects();
		_classPropertyManyRelationships.removeAllObjects();
		for (int i = 0; i < value.count(); i++) {
			EOProperty o = (EOProperty)value.objectAtIndex(i);
			_classPropertyNames.addObject(o.name());
			if (o instanceof EOAttribute) {
				_classPropertyAttributes.addObject(o);
			} else if (o instanceof EORelationship) {
				if (((EORelationship)o).isToMany())
					_classPropertyManyRelationships.addObject(o);
				else
					_classPropertyOneRelationships.addObject(o);
			}
		}
	}
	public NSArray classProperties() {
		if (_classProperties == null) {
			if (_classPropertyNames == null)
				return NSArray.EmptyArray;
			else {
				NSMutableArray props = new NSMutableArray();
				NSMutableArray atribs = new NSMutableArray();
				NSMutableArray ones = new NSMutableArray();
				NSMutableArray manies = new NSMutableArray();
				for (int i = 0; i < _classPropertyNames.count(); i++) {
					String name = (String)_classPropertyNames.objectAtIndex(i);
					EOAttribute a = attributeNamed(name);
					EORelationship r = relationshipNamed(name);
					if (a != null) {
						props.addObject(a);
						atribs.addObject(a);
					} else if (r != null) {
						props.addObject(r);
						if (r.isToMany())
							manies.addObject(r);
						else
							ones.addObject(r);
					} else
						throw new IllegalArgumentException("Cannot find attribute or relationship named " + name);
				}
				_classProperties = props;
				_classPropertyAttributes = atribs;
				_classPropertyOneRelationships = ones;
				_classPropertyManyRelationships = manies;
			}
		}
		return _classProperties;
	}

	public NSArray classPropertyNames() {
		return _classPropertyNames;
	}

	public NSArray classPropertyAttributeNames() {
		if (_classPropertyAttributes == null)
			return NSArray.EmptyArray;
		NSMutableArray arr = new NSMutableArray(_classPropertyAttributes.count());
		for (int i = 0 ; i < _classPropertyAttributes.count(); i++) {
			EOAttribute a = (EOAttribute)_classPropertyAttributes.objectAtIndex(i);
			arr.addObject(a.name());
		}
		return arr;
	}

	public NSArray classPropertyToManyRelationshipNames() {
		if (_classPropertyManyRelationships == null)
			return NSArray.EmptyArray;
		NSMutableArray arr = new NSMutableArray(_classPropertyManyRelationships.count());
		for (int i = 0 ; i < _classPropertyManyRelationships.count(); i++) {
			EOAttribute a = (EOAttribute)_classPropertyManyRelationships.objectAtIndex(i);
			arr.addObject(a.name());
		}
		return arr;
	}

	public NSArray classPropertyToOneRelationshipNames() {
		if (_classPropertyOneRelationships == null)
			return NSArray.EmptyArray;
		NSMutableArray arr = new NSMutableArray(_classPropertyOneRelationships.count());
		for (int i = 0 ; i < _classPropertyOneRelationships.count(); i++) {
			EOAttribute a = (EOAttribute)_classPropertyOneRelationships.objectAtIndex(i);
			arr.addObject(a.name());
		}
		return arr;
	}

	public void setIsAbstractEntity(boolean flag) {
		_isAbstract = flag;
	}
	public boolean isAbstractEntity() {
		return _isAbstract;
	}

	public void setReadOnly(boolean flag) {
		_isReadOnly = flag;
	}
	public boolean isReadOnly() {
		return _isReadOnly;
	}

	public void setStoredProcedure(EOStoredProcedure proc, String operation) {
	}
	public EOStoredProcedure storedProcedureForOperation(String operation) {
		return null;
	}

	public NSArray subEntities() {
		return null;
	}

	public NSArray attributesToFetch() {
		return attributes();
	}

	public NSArray externalModelsReferenced() {
		return null;
	}

	public EOClassDescription classDescriptionForInstances() {
		EOClassDescription cd = EOClassDescription.classDescriptionForEntityName(name());
		if (cd == null) {
			cd = new EOEntityClassDescription(this);
			Class cl = null;
			try {
				cl = Class.forName(className());
			} catch (ClassNotFoundException ex) {
				cl = EOGenericRecord.class;
			}
			EOClassDescription.registerClassDescription(cd, cl);
		}
		return cd;
	}

	/**
	 * Creates a global ID for a row. The row must have values
	 * for all the primary key attributes.
	 * @param row A raw row for this entity.
	 * @return A key global ID to identify this row.
	 */
	public EOGlobalID globalIDForRow(Map row) {
		NSArray pknames = primaryKeyAttributeNames();
		EOKeyGlobalID gid = null;
		if (pknames.count() == 1 && row.get(pknames.objectAtIndex(0)) instanceof Number) {
			Number n = (Number)row.get(pknames.objectAtIndex(0));
			gid = new EOIntegralKeyGlobalID(name(), n);
		} else {
			Object[] vals = new Object[pknames.count()];
			for (int i = 0; i < pknames.count(); i++) {
				Object v = row.get(pknames.objectAtIndex(i));
				vals[i] = v;
			}
			gid = new EOVectorKeyGlobalID(name(), vals);
		}
		return gid;
	}

	/**
	 * Returns a dictionary with the primary key values contained in 
	 * the global id.
	 * @param gid A Key global ID.
	 * @return A dictionary with the primary key values for gid.
	 */
	public NSDictionary primaryKeyForGlobalID(EOGlobalID gid) {
		if (!(gid instanceof EOKeyGlobalID))
			return null;
		Object[] vals = ((EOKeyGlobalID)gid).keyValues();
		NSArray pknames = primaryKeyAttributeNames();
		return new NSDictionary(vals, pknames.toArray());
	}

	public EOQualifier qualifierForPrimaryKey(Map pkey) {
		NSArray pknames = primaryKeyAttributeNames();
		EOQualifier q = null;
		NSMutableArray subq = new NSMutableArray(pknames.count());
		for (int i = 0; i < pknames.count(); i++) {
			String key = (String)pknames.objectAtIndex(i);
			Object v = pkey.get(key);
			if (v == null || v == NSKeyValueCoding.NullValue)
				throw new IllegalArgumentException("Primary key with null values.");
			subq.addObject(new EOKeyValueQualifier(key, EOQualifier.QualifierOperatorEqual, v));
		}
		if (subq.count() == 1)
			q = (EOQualifier)subq.objectAtIndex(0);
		else
			q = new EOAndQualifier(subq);
		return q;
	}

	public void setUserInfo(NSDictionary value) {
		_userInfo = value;
	}
	public NSDictionary userInfo() {
		return _userInfo;
	}

	public void awakeWithPropertyList(NSDictionary plist) {
	}

	public void encodeIntoPropertyList(NSMutableDictionary dict) {
		dict.setObjectForKey(name(), "name");
		dict.setObjectForKey(externalName(), "externalName");
		dict.setObjectForKey(className(), "className");

		//Encode attributes
		NSMutableArray arr = new NSMutableArray(_attributes.allValues());
		for (int i = 0; i < _attributes.count(); i++) {
			EOAttribute a = (EOAttribute)arr.objectAtIndex(i);
			NSMutableDictionary d = new NSMutableDictionary();
			a.encodeIntoPropertyList(d);
			arr.replaceObjectAtIndex(i, d);
		}
		dict.setObjectForKey(arr, "attributes");
		//Encode relationships
		if (_relations.count() > 0) {
			arr = new NSMutableArray(_relations.allValues());
			for (int i = 0; i < _relations.count(); i++) {
				EORelationship r = (EORelationship)arr.objectAtIndex(i);
				NSMutableDictionary d = new NSMutableDictionary();
				r.encodeIntoPropertyList(d);
				arr.replaceObjectAtIndex(i, d);
			}
			dict.setObjectForKey(arr, "relationships");
		}

		//Fetch specifications
		NSMutableDictionary d = new NSMutableDictionary();
		loadFetchSpecifications();
		java.util.Enumeration enumeration = _fetchSpecs.keyEnumerator();
		while (enumeration.hasMoreElements()) {
			String k = (String)enumeration.nextElement();
			EOFetchSpecification f = (EOFetchSpecification)_fetchSpecs.objectForKey(k);
			EOKeyValueArchiver arch = new EOKeyValueArchiver();
			f.encodeWithKeyValueArchiver(arch);
			d.setObjectForKey(arch.dictionary(), k);
		}
		dict.setObjectForKey(d, "fetchSpecificationDictionary");

		//Other information
		dict.setObjectForKey(_classPropertyNames, "classProperties");
		dict.setObjectForKey(_pkAttributeNames, "primaryKeyAttributes");
		arr = new NSMutableArray(_lockingAttributes);
		for (int i = 0; i < arr.count(); i++)
			arr.replaceObjectAtIndex(i, ((EOAttribute)arr.objectAtIndex(i)).name());
		dict.setObjectForKey(arr, "attributesUsedForLocking");
		if (_userInfo != null && _userInfo.count() > 0 )
			dict.setObjectForKey(_userInfo, "userInfo");
		if (_internalInfo != null && _internalInfo.count() > 0 )
			dict.setObjectForKey(_internalInfo, "internalInfo");
	}

	public EOAttribute _attributeForPath(String path) {
		NSArray comps = NSArray.componentsSeparatedByString(path, ".");
		if (comps.count() < 2)
			return null;
		EORelationship r = null;
		EOEntity e = this;
		for (int i = 0; i < comps.count()-1; i++) {
			String name = (String)comps.objectAtIndex(i);
			r = e.relationshipNamed(name);
			if (r == null)
				return null;
			e = r.destinationEntity();
		}
		return e.attributeNamed((String)comps.lastObject());
	}

}
/*
 * $Log$
 * Revision 1.2  2006/02/16 16:47:14  cgruber
 * Move some classes in to "internal" packages and re-work imports, etc.
 *
 * Also use UnsupportedOperationExceptions where appropriate, instead of WotonomyExceptions.
 *
 * Revision 1.1  2006/02/16 13:19:57  cgruber
 * Check in all sources in eclipse-friendly maven-enabled packages.
 *
 * Revision 1.9  2005/05/11 15:21:53  cgruber
 * Change enum to enumeration, since enum is now a keyword as of Java 5.0
 *
 * A few other comments in the code.
 *
 * Revision 1.8  2003/08/19 19:47:58  chochos
 * added some methods to handle EOGlobalIDs and primary keys.
 *
 * Revision 1.7  2003/08/14 02:13:56  chochos
 * implement and use _attributeForPath()
 *
 * Revision 1.6  2003/08/11 19:38:27  chochos
 * Can now read from a file and re-write to another file.
 *
 * Revision 1.5  2003/08/11 18:19:33  chochos
 * encoding into property list seems to work fine now.
 *
 * Revision 1.4  2003/08/09 01:39:04  chochos
 * better handling of class properties; use EOKeyValueArchiving to encode/decode fetch specifications; implement EOPropertyListEncoding
 *
 * Revision 1.3  2003/08/08 05:52:21  chochos
 * gets the class description for the entity.
 *
 * Revision 1.2  2003/08/08 02:14:20  chochos
 * now it can read stored procedures.
 *
 * Revision 1.1  2003/08/07 02:38:33  chochos
 * implementation of EOEntity. What works for now is reading an entity from file.
 *
 */