/*******************************************************************************
 * Copyright 2013 SAP AG
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *   http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/
package com.sap.core.odata.fit.mapping;

import java.util.Arrays;
import java.util.List;

import com.sap.core.odata.api.edm.EdmSimpleTypeKind;
import com.sap.core.odata.api.edm.FullQualifiedName;
import com.sap.core.odata.api.edm.provider.EdmProvider;
import com.sap.core.odata.api.edm.provider.EntityContainer;
import com.sap.core.odata.api.edm.provider.EntityContainerInfo;
import com.sap.core.odata.api.edm.provider.EntitySet;
import com.sap.core.odata.api.edm.provider.EntityType;
import com.sap.core.odata.api.edm.provider.Key;
import com.sap.core.odata.api.edm.provider.Mapping;
import com.sap.core.odata.api.edm.provider.Property;
import com.sap.core.odata.api.edm.provider.PropertyRef;
import com.sap.core.odata.api.edm.provider.Schema;
import com.sap.core.odata.api.edm.provider.SimpleProperty;
import com.sap.core.odata.api.exception.ODataException;

public class MapProvider extends EdmProvider {

  private static final String NAMESPACE = "map";
  private static int P1 = 0;
  private static int P2 = 1;
  private static int P3 = 2;
  private static int ENTITYTYPE = 3;
  private static int ENTITYSET = 4;
  private static String MAPPING_CONTAINER = "mappingContainer";

  private static int EDM = 0;
  private static int BACKEND = 1;

  private final String[][] mapping = {
      { "p1", "P01" },
      { "p2", "P02" },
      { "p3", "P03" },
      { "mapping", "MAPPING" },
      { "mappings", "MAPPINGS" }
  };

  public MapProvider() {
    buildSchema();
  }

  private List<Schema> schemas;
  private PropertyRef propertyRef;
  private Key key;
  private Property property1;
  private Property property2;
  private Property property3;
  private EntityType entityType;
  private EntitySet entitySet;
  private EntityContainer entityContainer;
  private Schema schema;

  @Override
  public List<Schema> getSchemas() throws ODataException {
    return schemas;
  }

  private void buildSchema() {
    propertyRef = new PropertyRef();
    propertyRef.setName("p1");

    key = new Key();
    key.setKeys(Arrays.asList(propertyRef));

    property1 = new SimpleProperty().setName(mapping[P1][EDM]).setType(EdmSimpleTypeKind.String).setMapping(new Mapping().setObject(mapping[P1][BACKEND]));
    property2 = new SimpleProperty().setName(mapping[P2][EDM]).setType(EdmSimpleTypeKind.String).setMapping(new Mapping().setObject(mapping[P2][BACKEND]));
    property3 = new SimpleProperty().setName(mapping[P3][EDM]).setType(EdmSimpleTypeKind.String).setMapping(new Mapping().setObject(mapping[P3][BACKEND]));

    entityType = new EntityType();
    entityType.setName(mapping[ENTITYTYPE][EDM]);
    entityType.setKey(key);
    entityType.setProperties(Arrays.asList(property1, property2, property3));
    entityType.setMapping(new Mapping().setObject(mapping[ENTITYTYPE][BACKEND]));

    entitySet = new EntitySet();
    entitySet.setName(mapping[ENTITYSET][EDM]);
    entitySet.setEntityType(new FullQualifiedName(NAMESPACE, mapping[ENTITYTYPE][EDM]));
    entitySet.setMapping(new Mapping().setObject(mapping[ENTITYSET][BACKEND]));

    entityContainer = new EntityContainer();
    entityContainer.setDefaultEntityContainer(true);
    entityContainer.setName(MAPPING_CONTAINER);
    entityContainer.setEntitySets(Arrays.asList(entitySet));

    schema = new Schema();
    schema.setNamespace("mapping");
    schema.setAlias(NAMESPACE);
    schema.setEntityContainers(Arrays.asList(entityContainer));
    schema.setEntityTypes(Arrays.asList(entityType));

    schemas = Arrays.asList(schema);
  }

  @Override
  public EntityType getEntityType(final FullQualifiedName edmFQName) throws ODataException {
    if (!NAMESPACE.equals(edmFQName.getNamespace()) || !mapping[ENTITYTYPE][EDM].equals(edmFQName.getName())) {
      throw new ODataException("not found: " + edmFQName);
    }

    return entityType;
  }

  @Override
  public EntitySet getEntitySet(final String entityContainer, final String name) throws ODataException {
    if (!MAPPING_CONTAINER.equals(entityContainer) || !mapping[ENTITYSET][EDM].equals(name)) {
      throw new ODataException("not found: " + entityContainer + ", " + name);
    }

    return entitySet;
  }

  @Override
  public EntityContainerInfo getEntityContainerInfo(final String name) throws ODataException {
    EntityContainerInfo entityContainerInfo = null;

    if (MAPPING_CONTAINER.equals(name) || (name == null)) {
      entityContainerInfo = new EntityContainerInfo().setName(MAPPING_CONTAINER).setDefaultEntityContainer(true);
    }

    return entityContainerInfo;
  }

}