import java.util.ArrayList;

/**
 * This class represents a row in the game and keeps track of which
 * columns within the row contain obstacles
 * 
 * @author Monique Shotande
 * @version November 2, 2017
 * Lab 11
 */
public class GameRow
{
    /** The list of positions occupied by obstacles in this row 
     * (excluding those occupied by the hero or villain) 
     */
    private ArrayList<Integer> occupiedPositions;

    /**
     * Default Constructor for a row where all 
     * columns are unoccupied by obstacles
     */
    public GameRow()
    {
        this.occupiedPositions = new ArrayList<Integer>();
    }
    
    /**
     * Add a column index for a obstacle occupying
     * space within this row
     * 
     * @param space int for the column index within the row
     *              occupied by an obstacle
     */
    public void addToOccupiedSpaces(int space) {
        occupiedPositions.add(space);
    }
    
    /**
     * Clear the list of obstacles occupying
     * space within this row
     */
    public void clearOccupiedSpaces() {
        occupiedPositions.clear();
    }

    /**
     * Are there any obstacles within this row?
     * 
     * @return true if the row has no obstacles
     */
    public boolean isEmptySpace()
    {
        return occupiedPositions.isEmpty();
    }

    /**
     * Is there an obstacle within this row at the specified column index?
     * 
     * @param space int for the column index within the row of interest
     * @return true if there is not an obstacle within the space for this row
     */
    public boolean isEmptySpace(int space)
    {
        return !occupiedPositions.contains(space);
    }

    /**
     * Where are the positions occupied by obstacles within this row?
     * 
     * @return list of integers, indicating positions occupied by obstacles
     *          (not including spaces occupied the hero or villain)
     */
    public ArrayList<Integer> getOccupiedPositions()
    {
        return occupiedPositions;
    }
}