// CSE 143, Autumn 2013
// Class ArrayIntList can be used to store a list of integers.  It
// has no fixed capacity.  It dynamically increases in size when necessary.

import java.util.*;

public class ArrayIntList {
	
	public static final int DEFAULT_SIZE = 10;

	private int[] elementData;    // list of integers
	private int size;             // current number of elements in the list
	
   // post: constructs an empty list of default capacity
	public ArrayIntList() {
		this(DEFAULT_SIZE);
	}
   
   // pre : capacity >= 0 (throws IllegalArgumentException if not)
   // post: constructs an empty list with the given capacity
   public ArrayIntList(int capacity) {
      if (capacity < 0) {
         throw new IllegalArgumentException("capacity: " + capacity);
      }
      size = 0;
      elementData = new int[capacity];
   }
	
   // post: the list will be one longer and the value will
   //       be added to the end
	public void add(int value) {
		add(size, value);
	}
	
   // pre : 0 <= index <= size
   // post: the list will be one longer and the value will be 
   //       at index in the list
	public void add(int index, int value) {
      if (index < 0 || index > size) {
         throw new IndexOutOfBoundsException("index: " + index);
      }
      size++;
		checkSize();
		for(int i = size - 1; i > index; i--) {
			elementData[i] = elementData[i - 1];
		}
		elementData[index] = value;
	}
	
   // pre : 0 <= index < size if this is not satisfied throws a 
   //          IndexOutOfBoundsException
   // post: returns the value at the passed in index
	public int get(int index) {
      checkIndex(index);
		return elementData[index];
	}
	
   // pre : 0 <= index < size (throws IndexOutOfBoundsException if not)
   // post: places the value at the given index in the list
	public void set(int index, int value) {
      checkIndex(size);
		elementData[index] = value;
	}
	
   // post: returns the current number of elements in the list
	public int size() {
		return size;
	}
	
   // post: returns true if list is empty, false otherwise
	public boolean isEmpty() {
		return size == 0;
	}
	
   // pre : 0 <= index < size() (throws IndexOutOfBoundsException if not)
   // post: removes value at the given index, shifting subsequent values left
	public void remove(int index) {
      checkIndex(index);
		for(int i = index; i < size - 1; i++) {
			elementData[i] = elementData[i + 1];
		}
		size--;
	}
	
   // post: returns a comma-separated, bracketed version of the list
	public String toString() {
		if (size == 0) {
			return "[]";
		} else {
			String result = "[" + elementData[0];
			for (int i = 1; i < size; i++) {
				result += ", " + elementData[i];
			}
			result += "]";
			return result;
		}
	}

	// post : returns the position of the first occurrence of the given
      //        value (-1 if not found)
	public int indexOf(int value) {
		for (int i = 0; i < size; i++) {
			if(elementData[i] == value) {
				return i;
			}
		}
		return -1;
	}
	
   // post: elementData is large enough to have at least one elment added
   //        if elementData is too small it doubles in size
	private void checkSize() {
		if(size > elementData.length) {
			int newCapacity = elementData.length * 2 + 1;
         elementData = Arrays.copyOf(elementData, newCapacity);
		}
	}
   
   
   // post: throws an IndexOutOfBoundsException if the given index is
   //       not a legal index of the current list
   private void checkIndex(int index) {
      if (index < 0 || index >= size) {
         throw new IndexOutOfBoundsException("index: " + index);
      }
   }
	
}