/**
 * An implementation of the BagOfPets Interface 
 * 
 * Note that everything marked with @Override does not need documentation as it
 * should be documented elsewhere.
 * @author gtowell
 * Created: July 2021
 * 
 */
public class StuffBag<R> implements BagOfStuff<R> {
    /** The array holding the information in the bag */
    private R[] stuffArray;

    /**
     * The default constructor.  
     * Creates a bag that can hold 100 stuff.
     */
    public StuffBag() {
        this(100);
    }
    
    /**
     * Constructor for stuff bag
     * param sizeOfBag  is the size of the bag
    */
    @SuppressWarnings("unchecked")
    public StuffBag(int sizeOfBag) {
        stuffArray = (R[])new Object[sizeOfBag];
    }

    @Override
    public int numberOfItems() {
        int count = 0;
        for (int i = 0; i < stuffArray.length; i++) {
            if (stuffArray[i] != null)
                count++;
        }
        return count;
    }

    @Override
    public boolean isEmpty() {
        return numberOfItems() == 0;
    }

    @Override
    public boolean add(R p) {
        int loc=0;
        while (loc < stuffArray.length && stuffArray[loc] != null) {
            loc++;
        }
        if (loc == stuffArray.length){
            return false;
        } else {
            stuffArray[loc] = p;
            return true;
        }
    }

    @Override
    public R remove() {
        int loc=0;
        while (loc < stuffArray.length && stuffArray[loc] == null) {
            loc++;
        }
        if (loc == stuffArray.length){
            return null;
        } else {
            R tmp = stuffArray[loc];
            stuffArray[loc] = null;
            return tmp;
        }
    }

    @Override
    public boolean remove(R p) {
        boolean found = false;
        for (int i = 0; i < stuffArray.length; i++) {
            if (stuffArray[i] == p) {
                found = true;
                stuffArray[i] = null;
            }
        }
        return found;
    }

    @Override
    public void clear() {
        for (int i = 0; i < stuffArray.length; i++) {
            stuffArray[i] = null;
        }
    }

    @Override
    public int countOf(R p) {
        int count = 0;
        for (int i = 0; i < stuffArray.length; i++) {
            if (stuffArray[i] == p) {
                count++;
            }
        }
        return count;
    }

    @Override
    public boolean contains(R p) {
        return countOf(p) > 0;
    }

    @Override
    public R getInstance(R p) {
        for (int i = 0; i < stuffArray.length; i++) {
            if (stuffArray[i].equals(p)) {
                return stuffArray[i];
            }
        }
        return null;
    }

    @Override
    public void display() {
        System.out.println(toString());
    }

    @Override
    public String toString() {
        StringBuffer sb = new StringBuffer();
        for (int i = 0; i < stuffArray.length; i++) {
            if (stuffArray[i] != null) {
                sb.append(stuffArray[i].toString());
                sb.append("\n");
            }
        }
        return sb.toString();
    }
    
}