/*******************************************************************************
    * Copyright 2013 André Rouél and Dominik Seichter
    * 
    * 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 net.sf.qualitytest.blueprint.strategy.creation;
  
  import java.text.MessageFormat;
  import java.util.HashMap;
  import java.util.Map;
  
  import javax.annotation.Nonnull;
  
  import net.sf.qualitycheck.ArgumentsChecked;
  import net.sf.qualitycheck.Check;
  import net.sf.qualitycheck.Throws;
  import net.sf.qualitycheck.exception.IllegalNotNullArgumentException;
  import net.sf.qualitytest.blueprint.BlueprintConfiguration;
  import net.sf.qualitytest.blueprint.BlueprintExceptionRunnable;
  import net.sf.qualitytest.blueprint.BlueprintSession;
  import net.sf.qualitytest.blueprint.CreationStrategy;
  import net.sf.qualitytest.blueprint.SafeInvoke;
  import net.sf.qualitytest.blueprint.SafeInvoke.ExceptionRunnable;
  import net.sf.qualitytest.exception.BlueprintException;
  
  /**
   * Strategy to create values and increment each new value by 1. This is useful to create tests which are not random but
   * use not the same value for each type every time.
   * 
   * @author Dominik Seichter
   */
  public class IncrementValueCreationStrategy<T extends Number> implements CreationStrategy<T> {
  
  	private static final Map<Class<?>, Class<? extends Number>> PRIMITIVE_MAPPING = new HashMap<Class<?>, Class<? extends Number>>();
  
  	static {
  		PRIMITIVE_MAPPING.put(Integer.TYPE, Integer.class);
  		PRIMITIVE_MAPPING.put(Long.TYPE, Long.class);
  		PRIMITIVE_MAPPING.put(Double.TYPE, Double.class);
  		PRIMITIVE_MAPPING.put(Float.TYPE, Float.class);
  		PRIMITIVE_MAPPING.put(Byte.TYPE, Byte.class);
  		PRIMITIVE_MAPPING.put(Short.TYPE, Short.class);
  	};
  
  	private static final long DEFAULT_OFFSET = 1L;
  	private T currentValue;
  	private final long offset;
  	private final long maxValueOfType;
  
  	@ArgumentsChecked
  	public IncrementValueCreationStrategy(@Nonnull final T initialValue) {
  		this.currentValue = Check.notNull(initialValue, "initialValue");
  		this.offset = DEFAULT_OFFSET;
  		this.maxValueOfType = readMaxValueOfType();
  	}
  
  	@ArgumentsChecked
  	public IncrementValueCreationStrategy(@Nonnull final T initialValue, final long offset) {
  		this.currentValue = Check.notNull(initialValue, "initialValue");
  		this.offset = offset;
  		this.maxValueOfType = readMaxValueOfType();
  	}
  
  	@ArgumentsChecked
  	@Throws(IllegalNotNullArgumentException.class)
  	public T createValue(final Class<?> expectedClazz, final BlueprintConfiguration config, final BlueprintSession session) {
  		Check.notNull(expectedClazz, "expectedClazz");
  
  		final long value = (currentValue.longValue() % maxValueOfType) + offset;
  		final String action = MessageFormat.format("Creating value {0} for type {1}.", value, expectedClazz);
  		currentValue = SafeInvoke.invoke(new BlueprintExceptionRunnable<T>(session, action) {
  			@SuppressWarnings("unchecked")
  			@Override
  			public T runInternal() throws Exception {
  				if (expectedClazz.isPrimitive()) {
  					final Class<?> clazz = PRIMITIVE_MAPPING.get(expectedClazz);
  					return (T) clazz.getConstructor(String.class).newInstance(String.valueOf(value));
  				} else {
  					return (T) expectedClazz.getConstructor(String.class).newInstance(String.valueOf(value));
  				}
  			}
  
  		}, BlueprintException.class);
  
  		return currentValue;
  	}
  
  	private long readMaxValueOfType() {
  		final Number n = SafeInvoke.invoke(new ExceptionRunnable<Number>() {
 			@Override
 			public Number run() throws Exception {
 				return (Number) currentValue.getClass().getField("MAX_VALUE").get(null);
 			}
 
 		}, BlueprintException.class);
 		return n.longValue();
 	}
 }