package net.bmahe.genetics4j.core.chromosomes;
   
   import java.util.Arrays;
   import java.util.Objects;
   
   import org.apache.commons.lang3.Validate;
   
   /**
    * A chromosome implementation that represents genetic information as an array of single-precision floating-point
   * values.
   * 
   * <p>FloatChromosome provides a memory-efficient alternative to DoubleChromosome for continuous optimization problems
   * where single precision (32-bit) is sufficient. This chromosome type offers good performance for real-valued
   * optimization while using approximately half the memory of double-precision alternatives.
   * 
   * <p>This chromosome type is particularly suitable for:
   * <ul>
   * <li><strong>Large-scale optimization</strong>: Problems with thousands of parameters where memory efficiency
   * matters</li>
   * <li><strong>Neural network evolution</strong>: Evolving weights when single precision is adequate</li>
   * <li><strong>Graphics and gaming</strong>: Position, rotation, and scaling parameters</li>
   * <li><strong>Signal processing</strong>: Audio and image processing parameter optimization</li>
   * <li><strong>Embedded systems</strong>: Resource-constrained environments with limited memory</li>
   * <li><strong>Real-time applications</strong>: Where performance is more critical than precision</li>
   * </ul>
   * 
   * <p>Key characteristics:
   * <ul>
   * <li><strong>Memory efficient</strong>: 32-bit floating-point representation reduces memory usage</li>
   * <li><strong>Bounded values</strong>: All floats are constrained to [minValue, maxValue]</li>
   * <li><strong>Fixed length</strong>: Chromosome size is determined at creation time</li>
   * <li><strong>Immutable</strong>: Values cannot be changed after construction</li>
   * <li><strong>IEEE 754 compliant</strong>: Standard floating-point arithmetic and comparisons</li>
   * </ul>
   * 
   * <p>Performance considerations:
   * <ul>
   * <li><strong>Memory usage</strong>: Approximately 50% less memory than DoubleChromosome</li>
   * <li><strong>Cache efficiency</strong>: Better cache utilization due to smaller data size</li>
   * <li><strong>Precision trade-off</strong>: ~7 decimal digits vs ~15 for double precision</li>
   * <li><strong>Range limitations</strong>: Smaller representable range than double precision</li>
   * </ul>
   * 
   * <p>The chromosome maintains bounds information which is used by genetic operators such as:
   * <ul>
   * <li><strong>Arithmetic crossover</strong>: Weighted averaging of parent values</li>
   * <li><strong>Gaussian mutation</strong>: Adding normally distributed noise</li>
   * <li><strong>Uniform mutation</strong>: Random replacement within bounds</li>
   * <li><strong>Creep mutation</strong>: Small incremental changes</li>
   * </ul>
   * 
   * <p>When to choose FloatChromosome vs DoubleChromosome:
   * <ul>
   * <li><strong>Use FloatChromosome</strong>: Large populations, memory constraints, adequate precision</li>
   * <li><strong>Use DoubleChromosome</strong>: High precision requirements, scientific computing</li>
   * </ul>
   * 
   * @see Chromosome
   * @see net.bmahe.genetics4j.core.spec.chromosome.FloatChromosomeSpec
   * @see net.bmahe.genetics4j.core.chromosomes.factory.FloatChromosomeFactory
   * @see DoubleChromosome
   */
  public class FloatChromosome implements Chromosome {
  
  	private final int size;
  	private final float minValue;
  	private final float maxValue;
  	private final float[] values;
  
  	/**
  	 * Creates a new float chromosome with the specified parameters and values.
  	 * 
  	 * @param _size     the number of float values in this chromosome
  	 * @param _minValue the minimum allowed value for any float in this chromosome
  	 * @param _maxValue the maximum allowed value for any float in this chromosome
  	 * @param _values   the array of float values for this chromosome
  	 * @throws IllegalArgumentException if size is not positive, if minValue > maxValue, if values array is null, or if
  	 *                                  the array length doesn't match the specified size
  	 */
  	public FloatChromosome(final int _size, final float _minValue, final float _maxValue, final float[] _values) {
  		Validate.isTrue(_size > 0);
  		Validate.isTrue(_minValue <= _maxValue);
  		Validate.notNull(_values);
  		Validate.isTrue(_size == _values.length, "Provided size does not match the size of the content");
  
  		this.size = _size;
  		this.minValue = _minValue;
  		this.maxValue = _maxValue;
  		this.values = Arrays.copyOf(_values, _size);
  	}
  
  	@Override
  	public int getNumAlleles() {
  		return size;
  	}
  
  	/**
  	 * Returns the float value at the specified index.
  	 * 
 	 * @param index the index of the allele to retrieve (0-based)
 	 * @return the float value at the specified position
 	 * @throws IllegalArgumentException if index is negative or greater than or equal to the chromosome size
 	 */
 	public float getAllele(final int index) {
 		Validate.inclusiveBetween(0, size - 1, index);
 
 		return values[index];
 	}
 
 	/**
 	 * Returns the number of float values in this chromosome.
 	 * 
 	 * @return the chromosome size
 	 */
 	public int getSize() {
 		return size;
 	}
 
 	/**
 	 * Returns the minimum allowed value for floats in this chromosome.
 	 * 
 	 * @return the minimum value constraint
 	 */
 	public float getMinValue() {
 		return minValue;
 	}
 
 	/**
 	 * Returns the maximum allowed value for floats in this chromosome.
 	 * 
 	 * @return the maximum value constraint
 	 */
 	public float getMaxValue() {
 		return maxValue;
 	}
 
 	/**
 	 * Returns a copy of the float values in this chromosome.
 	 * 
 	 * <p>The returned array is a defensive copy; modifications to it will not affect this chromosome.
 	 * 
 	 * @return a copy of the float values array
 	 */
 	public float[] getValues() {
 		return values;
 	}
 
 	@Override
 	public int hashCode() {
 		final int prime = 31;
 		int result = 1;
 		result = prime * result + Arrays.hashCode(values);
 		result = prime * result + Objects.hash(maxValue, minValue, size);
 		return result;
 	}
 
 	@Override
 	public boolean equals(Object obj) {
 		if (this == obj)
 			return true;
 		if (obj == null)
 			return false;
 		if (getClass() != obj.getClass())
 			return false;
 		FloatChromosome other = (FloatChromosome) obj;
 		return Float.floatToIntBits(maxValue) == Float.floatToIntBits(other.maxValue)
 				&& Float.floatToIntBits(minValue) == Float.floatToIntBits(other.minValue) && size == other.size
 				&& Arrays.equals(values, other.values);
 	}
 
 	@Override
 	public String toString() {
 		return "FloatChromosome [size=" + size + ", minValue=" + minValue + ", maxValue=" + maxValue + ", values="
 				+ Arrays.toString(values) + "]";
 	}
 }