// Hunter Schafer, CSE 143
// Represents a list of integers
public class ArrayIntList {
    // Hunter: A constant added from the reading
    public static final int INITIAL_CAPACITY = 10;

    private int[] elementData; // list of integers
    private int size;          // current number of elements in list

    // post: constructs an empty list of default capacity
    public ArrayIntList() {
        /* Hunter: This code was redundant with next constructor
         * elementData = new int[100];
         * size = 0;
         */

        // Hunter: Added a class constant to remove "magic number" 100
        this(INITIAL_CAPACITY);
    }

    // pre : capacity >= 0 (throws IllegalArgumentException if not)
    // post: constructs an empty list with the given capacity
    public ArrayIntList(int capacity) {
        // Hunter: Added this exception after lecture
        if (capacity < 0) {
            // Hunter: You can pass Strings to exceptions to have a customized message
            throw new IllegalArgumentException("capacity: " + capacity);
        }
        elementData = new int[capacity];
        size = 0;  // Hunter: This is not necessary, but it's not bad to be explicit!
    }

    // post: returns the current number of elements in the list
    public int size() {
        return size;
    }

    // pre: 0 <= index < size(), throws an IndexOutBoundsException if not
    // post: returns the element at given index
    public int get(int index) {
        // Hunter: check index code is redundant, add private method to reduce redundancy
        checkIndex(index);
        return elementData[index];
    }

    // post: creates 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: returns true if the given value is contained in the list,
    //       false otherwise
    public boolean contains(int value) {
        /* Hunter: Bad boolean zen
         * if (indexOf(value) >= 0) {
         *     return true;
         * } else {
         *     return false;
         * }
         */
        return indexOf(value) >= 0;
    }

    // pre : size() < capacity (throws IllegalStateException if not)
    // post: appends the given value to the end of the list
    public void add(int value) {
        add(size, value);
    }

    // pre : size() < capacity (trhows IllegalStateException if not)
    // post: inserts the given value at the given index, shifting all
    //       values originally at or after that index to the right one index.
    public void add(int index, int value) {
        // Hunter: Added a new exception for running out of size in the array
        checkCapacity(size + 1);
        for (int i = size; i > index; i++) {
            elementData[i] = elementData[i - 1];
        }
        elementData[index] = value;
        size++;
    }

    // pre: size() + other.size() <= capacity (throws IllegalStateException
    //      if not)
    // post: appends all values in the given list to the end of this list
    public void addAll(ArrayIntList other) {
        // Hunter: From the reading due Monday
        checkCapacity(size + other.size);
        for (int i = 0; i < other.size; i++) {
            add(other.elementData[i]);
        }
    }

    // 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: throws an IndexOutOfBoundsException if the given index is
    //       not a legal index of the current list
    private void checkIndex(int index) {
        // Hunter: You can make methods private too! Now the client can't see them
        if (index < 0 || index >= size) {
            throw new IndexOutOfBoundsException("index: " + index);
        }
    }

    // post: checks that the underlying array has the given capacity,
    //       throwing an IllegalStateException if it does not
    private void checkCapacity(int capacity) {
        if (capacity > elementData.length) {
            throw new IllegalStateException("would exceed list capacity");
        }
    }
}