/**
 * Copyright (C) 2003-2008 eXo Platform SAS.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Affero General Public License
 * as published by the Free Software Foundation; either version 3
 * of the License, or (at your option) any later version.
 * 
 * This program 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, see<http://www.gnu.org/licenses/>.
 */

package org.etk.core.rest.impl.method;

import java.lang.reflect.Method;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

import javax.ws.rs.core.MultivaluedMap;

/**
 * Construct a primitive type from string value.
 * 
 * @author <a href="mailto:andrew00x@gmail.com">Andrey Parfonov</a>
 * @version $Id: $
 */
public final class PrimitiveTypeProducer extends BaseTypeProducer {

  /**
   * Primitive types map, this map contains all primitive java types except char
   * because {@link Character} has not static method valueOf with String
   * parameter.
   */
  static final Map<String, Class<?>>       PRIMITIVE_TYPES_MAP;

  /**
   * Default values for primitive types. This value will be used if not found
   * required parameter in request and default value
   * {@link javax.ws.rs.DefaultValue} is null.
   */
  private static final Map<String, Object> PRIMITIVE_TYPE_DEFAULTS;

  static {
    Map<String, Class<?>> m = new HashMap<String, Class<?>>(7);
    m.put("boolean", Boolean.class);
    m.put("byte", Byte.class);
    m.put("short", Short.class);
    m.put("int", Integer.class);
    m.put("long", Long.class);
    m.put("float", Float.class);
    m.put("double", Double.class);
    PRIMITIVE_TYPES_MAP = Collections.unmodifiableMap(m);
  }

  static {
    Map<String, Object> m = new HashMap<String, Object>(7);
    m.put("boolean", Boolean.valueOf(false));
    m.put("byte", Byte.valueOf((byte) 0));
    m.put("short", Short.valueOf((short) 0));
    m.put("int", Integer.valueOf(0));
    m.put("long", Long.valueOf(0L));
    m.put("float", Float.valueOf(0.0F));
    m.put("double", Double.valueOf(0.0d));
    PRIMITIVE_TYPE_DEFAULTS = Collections.unmodifiableMap(m);
  }

  /**
   * Class of object which will be created.
   */
  private Class<?>                         clazz;

  /**
   * This will be used if defaultValue is null.
   */
  private Object                           defaultDefaultValue;

  /**
   * Construct PrimitiveTypeProducer.
   * 
   * @param clazz class of object
   */
  PrimitiveTypeProducer(Class<?> clazz) {
    this.clazz = clazz;

    /**
     * If class is represents primitive type then method {@link Class#getName()}
     * return name of primitive type. See #PRIMITIVE_TYPES_MAP.
     */
    this.defaultDefaultValue = PRIMITIVE_TYPE_DEFAULTS.get(clazz.getName());
  }

  /**
   * {@inheritDoc}
   */
  @Override
  protected Object createValue(String value) throws Exception {

    /**
     * If class is represents primitive type then method {@link Class#getName()}
     * return name of primitive type. See #PRIMITIVE_TYPES_MAP.
     */
    Class<?> c = PRIMITIVE_TYPES_MAP.get(clazz.getName());
    Method method = ParameterHelper.getStringValueOfMethod(c);

    // invoke valueOf method for creation object
    return method.invoke(null, value);
  }

  /**
   * {@inheritDoc}
   */
  @Override
  public Object createValue(String param, MultivaluedMap<String, String> values, String defaultValue) throws Exception {
    String value = values.getFirst(param);

    if (value != null)
      return createValue(value);
    else if (defaultValue != null)
      return createValue(defaultValue);

    return this.defaultDefaultValue;
  }

}