package listadt;

import java.util.function.Function;

/**
 * This is a non-empty node in a generic list. It contains the object data
 * and the rest of the list
 */
public class GenericElementNode<T> implements GenericListADTNode<T> {
  private T object;
  private GenericListADTNode<T> rest;

  public GenericElementNode(T p,GenericListADTNode<T> rest) {
    this.object = p;
    this.rest = rest;
  }

  @Override
  public int count() { return 1+this.rest.count();}



  @Override
  public GenericListADTNode<T> addFront(T object) {
    return new GenericElementNode(object,this);
  }

  @Override
  public GenericListADTNode<T> addBack(T object) {
    this.rest = this.rest.addBack(object);
    return this;
  }

  @Override
  public GenericListADTNode<T> add(int index,T object) {
    if (index==0) {
      return addFront(object);
    }
    else {
      this.rest = this.rest.add(index-1,object);
      return this;
    }
  }

  @Override
  public GenericListADTNode<T> remove(T object) {
    if (this.object.equals(object)) {
      return this.rest;
    }
    else {
      this.rest = this.rest.remove(object);
      return this;
    }
  }

  @Override
  public T get(int index) throws IllegalArgumentException{
    if (index==0) return this.object;
    return this.rest.get(index-1);
  }

  @Override
  public <R> GenericListADTNode<R> map(Function<T,R> converter) {
    /* Starting from this list of T, the resulting list of type R is an
    element that contains this data converted to T, followed by the rest of
    the converted list
     */
    return new GenericElementNode(
            converter.apply(this.object),
            this.rest.map(converter));
  }

  @Override
  public String toString() {
    String objstring = this.object.toString();
    String rest = this.rest.toString();
    if (rest.length()>0)
      return objstring + " " + rest;
    else
      return objstring;
  }
}