package username.sorting;

import java.io.PrintWriter;

import java.util.Comparator;

/**
 * Something that knows how to test sorters.
 *
 * @author CSC152 2006S
 * @author Samuel A. Rebelsky
 * @version 1.0 of April 2006
 */
public class SortTester
{
    /**
     * Test a sorter, printing results with pen.
     */
    public static void test(PrintWriter pen, Sorter<Integer> s)
    {
        boolean ok = true;
        IntegerComparator c = new IntegerComparator();
        // For a variety of sizes
        for (int i = 1; i < 65; i++) {
            if (!test(pen, s, c, i)) {
                ok = false;
            }
        } // for (int i)
        // If no tests failed, print a success message.
        if (ok) {
          pen.println("All tests succeeded.");
        }
    } // test(PrintWriter, Sorter<Integer>)

    /**
     * Test a sorter on a vector of size i.
     */
    static boolean test(PrintWriter pen, Sorter<Integer> s, Comparator<Integer> c, int n)
    {
        // Build a sorted vector of the appropriate size.
        Vector<Integer> vec = IVUtils.sortedVector(n);
        // Make a copy of that vector.
        Vector<Integer> copy = IVUtils.clone(vec);
        // Permute that copy
        IVUtils.permute(copy);
        // Sort that copy
        Vector<Integer> sorted = s.sort(copy, c);
        // Compare the two
        for (int i = 0; i < n; i++) {
            if (c.compare(vec.get(i),sorted.get(i)) != 0) {
                pen.println("Failed to sort " + copy);
                pen.println("  Incorrect:   " + sorted);
                return false;
            }
        } // for
        // Yay!  No errors.
        return true;
   } // test(PrintWriter, Sorter<Integer>, Comparator<Integer>, int)

} // class SortTester