Metadata.java

package com.breeze.metadata;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

import com.breeze.metadata.DataType;
import com.breeze.metadata.IDataProperty;
import com.breeze.metadata.IEntityType;
import com.breeze.metadata.INavigationProperty;
import com.breeze.metadata.IProperty;
import com.breeze.metadata.MetadataHelper;
import com.breeze.util.JsonGson;

/**
 * Strongly typed metadata the describes all of the entityTypes for a single model and all of their associated data and navigation properties.
 * @author IdeaBlade
 *
 */
@SuppressWarnings("unchecked")
public abstract class Metadata  {
	private HashMap<String, Object> _resourceEntityTypeMap;
	private HashMap<String, IEntityType> _entityTypeMap = new HashMap<String, IEntityType>();
	private RawMetadata  _rawMetadata;
	
	
	public void build() {
	    if (_rawMetadata == null) {
	        _rawMetadata = buildRawMetadata();
	        wrapRawMetadata(_rawMetadata);
	    }
	}
	
	protected abstract RawMetadata buildRawMetadata();
	
	/**
     * Creates strongly typed wrapper over raw breeze json metadata.  
     * @param rawMetadata The raw metadata in json format that is used to communicate with the breeze client. 
     */
    private void wrapRawMetadata(RawMetadata rawMetadata) {
        _rawMetadata = rawMetadata;
        List<HashMap<String, Object>> structuralTypes = (List<HashMap<String, Object>>) rawMetadata.get("structuralTypes");
        _resourceEntityTypeMap = (HashMap<String, Object>) rawMetadata.get("resourceEntityTypeMap");
        for (Map<String, Object> entityMap: structuralTypes) {
            IEntityType entityType = new EntityType(entityMap, this);
            _entityTypeMap.put(entityType.getName(), entityType);
        }
    }
	
	public RawMetadata getRawMetadata() {
	    return _rawMetadata;
	}
	
	public String toJson() {
	    return JsonGson.toJson(this._rawMetadata);
	}
	
	/**
	 * @param resourceName The name of the url resource.  
	 * @return The EntityType associated with the specified resource name.
	 */
	public IEntityType getEntityTypeForResourceName(String resourceName) {
		String entityTypeName = (String) _resourceEntityTypeMap.get(resourceName);
		if (entityTypeName == null) {
			throw new RuntimeException("There is no entityType name registered for this resource: " + resourceName);
		}
		return getEntityType(entityTypeName);
	}
	
	
	/**
	 * @param clazz An entity class.
	 * @return The EntityType associated with the specified class.
	 */
	public IEntityType getEntityTypeForClass(Class<?> clazz) {
		String entityTypeName = MetadataHelper.getEntityTypeName(clazz);
		return getEntityType(entityTypeName);
	}

	/**
	 * @param entityTypeName An EntityType name.
	 * @return The EntityType associated with the specified name.
	 */
	public IEntityType getEntityType(String entityTypeName) {
		if (entityTypeName == null) return null;
		return _entityTypeMap.get(entityTypeName);
	}
	
	
	/**
	 * The metadata that describes a single java entity class.
	 * @author IdeaBlade
	 *
	 */
	public class EntityType implements IEntityType {
		private Map<String, Object> _entityMap;
		private Metadata _metadata;
		
		private String _entityTypeName;
		private Map<String, IProperty> _propertyMap = new HashMap<String, IProperty>();
		private List<IDataProperty> _keyProperties = new ArrayList<IDataProperty>();

		protected EntityType(Map<String, Object> entityMap, Metadata metadata) {
			_entityMap = entityMap;
			_metadata = metadata;
			String ns = (String) _entityMap.get("namespace");
			String shortName = (String) _entityMap.get("shortName");
			_entityTypeName = MetadataHelper.getEntityTypeName(ns, shortName);
			
			List<HashMap<String, Object>> properties;
			properties = (List<HashMap<String, Object>>) _entityMap.get("dataProperties");
			for (HashMap<String, Object> p: properties) {
				IDataProperty prop = new DataProperty(this, p, metadata);
				if (prop.isKeyProperty()) {
				    _keyProperties.add(prop);
				}
				_propertyMap.put(prop.getName(), prop);
			}
			properties = (List<HashMap<String, Object>>) _entityMap.get("navigationProperties");
			if (properties != null) {
				for (HashMap<String, Object> p: properties) {
					INavigationProperty prop = new NavigationProperty(this, p, metadata);
					_propertyMap.put(prop.getName(), prop);
				}
			}
		}

		/* (non-Javadoc)
		 * @see com.breeze.metadata.IEntityType#getName()
		 */
		@Override
		public String getName() {
			return _entityTypeName;
		}
		
		public Metadata getMetadata() {
		    return _metadata;
		}

		@Override
		public IProperty getProperty(String propertyName) {
			return _propertyMap.get(propertyName);
		}
		
		public List<IDataProperty> getKeyProperties() {
		    return _keyProperties;
		}
		
		public boolean isComplexType() {
			Boolean isComplexType = (Boolean) _entityMap.get("isComplexType");
			return isComplexType != null && isComplexType == true;
		}
		
		public AutoGeneratedKeyType getAutoGeneratedKeyType() {
		    String tmp = (String) _entityMap.get("autoGeneratedKeyType");
		    if (tmp == null) {
		        return AutoGeneratedKeyType.None;
		    } else {
		        return AutoGeneratedKeyType.valueOf(tmp);
		    }
	    
		}
	}
	
	public class DataProperty implements IDataProperty {
		private IEntityType _parentType;
		private Map<String, Object> _dpMap;
		private Metadata _metadata;
		public DataProperty(IEntityType parentType, Map<String, Object> dpMap, Metadata metadata) {
			_parentType = parentType;
			_dpMap = dpMap;
			_metadata = metadata;
		}
		@Override
		public String getName() {
			return (String) _dpMap.get("nameOnServer");
		}
		
		public boolean isKeyProperty() {
		    Boolean isKey = (Boolean) _dpMap.get("isPartOfKey");
            return isKey == null ? false : isKey.booleanValue();
		}

		@Override
		public DataType getDataType() {
			String dataTypeName = (String) _dpMap.get("dataType");
			if (dataTypeName == null) return null;
			return DataType.fromName(dataTypeName);
		}
		
		public IEntityType getComplexType() {
			String complexTypeName = (String) _dpMap.get("complexTypeName");
			if (complexTypeName == null) return null;
			return _metadata.getEntityType(complexTypeName);
		}
		
		@Override
		public IEntityType getParentType() {
			return _parentType;
		}
		
		public Class getEnumType() {
		    String enumTypeName = (String) _dpMap.get("enumType");
		    try {
		        return enumTypeName == null ? null : Class.forName(enumTypeName);
		    } catch (ClassNotFoundException e) {
		        return null;
		    }
		}
	}
	
	public class NavigationProperty implements INavigationProperty {
		private IEntityType _parentType;
		private Map<String, Object> _npMap;
		private Metadata _metadata;
		public NavigationProperty(IEntityType parentType, Map<String, Object> npMap, Metadata metadata) {
			_parentType = parentType;
			_npMap = npMap;
			_metadata = metadata;
		}
		@Override
		public String getName() {
			return (String) _npMap.get("nameOnServer");
		}
		
		@Override
		public IEntityType getEntityType() {
			String entityTypeName = (String) _npMap.get("entityTypeName");
			return _metadata.getEntityType(entityTypeName);
		}
		
		@Override
		public IEntityType getParentType() {
			return _parentType;
		}

		@Override
		public boolean isScalar() {
			return (boolean) _npMap.get("isScalar");
		}
		
		public String[] getInvForeignKeyNames() {
		    Object invFkNames = _npMap.get("invForeignKeyNamesOnServer");
		    return (String[]) invFkNames;
		}
		
	}
	

}