package jalview.util;

import static org.testng.AssertJUnit.assertEquals;
import static org.testng.AssertJUnit.assertTrue;

import java.util.Arrays;

import org.testng.annotations.BeforeMethod;
import org.testng.annotations.Test;

public class QuickSortTest
{
  private static final String c1 = "Blue";

  private static final String c2 = "Yellow";

  private static final String c3 = "Orange";

  private static final String c4 = "Green";

  private Object[] things;

  private final Object[] sortedThings = new Object[]
  { c4, c2, c1, c3 };

  @BeforeMethod
  public void setUp()
  {
    things = new Object[]
    { c1, c2, c3, c4 };
  }

  @Test(groups ={ "Functional" })
  public void testSort_byIntValues()
  {
    int[] values = new int[]
    { 3, 2, 4, 1 };
    QuickSort.sort(values, things);
    assertTrue(Arrays.equals(new int[]
    { 1, 2, 3, 4 }, values));
    assertTrue(Arrays.equals(sortedThings, things));
  }

  @Test(groups ={ "Functional" })
  public void testSort_byFloatValues()
  {
    float[] values = new float[]
    { 3f, 2f, 4f, 1f };
    QuickSort.sort(values, things);
    assertTrue(Arrays.equals(new float[]
    { 1f, 2f, 3f, 4f }, values));
    assertTrue(Arrays.equals(sortedThings, things));
  }

  @Test(groups ={ "Functional" })
  public void testSort_byDoubleValues()
  {
    double[] values = new double[]
    { 3d, 2d, 4d, 1d };
    QuickSort.sort(values, things);
    assertTrue(Arrays.equals(new double[]
    { 1d, 2d, 3d, 4d }, values));
    assertTrue(Arrays.equals(sortedThings, things));
  }

  /**
   * Sort by String is descending order, case-sensitive
   */
  @Test(groups ={ "Functional" })
  public void testSort_byStringValues()
  {
    String[] values = new String[]
    { "JOHN", "henry", "lucy", "ALISON" };
    QuickSort.sort(values, things);
    assertTrue(Arrays.equals(new String[]
    { "lucy", "henry", "JOHN", "ALISON" }, values));
    assertTrue(Arrays.equals(new Object[]
    { c3, c2, c1, c4 }, things));
  }

  /**
   * Test whether sort is stable i.e. equal values retain their mutual ordering.
   */
  @Test(groups =
  { "Functional" }, enabled = false)
  public void testSort_withDuplicates()
  {
    int[] values = new int[]
    { 3, 4, 2, 4, 1 };
    Object [] things = new Object [] {"A", "X", "Y", "B", "Z"};
    QuickSort.sort(values, things);
    assertTrue(Arrays.equals(new int[]
    { 1, 2, 3, 4, 4 }, values));
    // this fails - do we care?
    assertTrue(Arrays.equals(new Object[]
    { "Z", "Y", "A", "X", "B" }, things));
  }

  /**
   * Test that exercises sort with a mostly zero-valued sortby array. May be of
   * interest to check the sort algorithm is efficient.
   */
  @Test(groups ={ "Functional" })
  public void testSort_MostlyZeroValues()
  {
    char[] residues = new char[64];
    for (int i = 0; i < 64; i++)
    {
      residues[i] = (char) i;
    }
    float[] counts = new float[64];
    counts[43] = 16;
    counts[59] = 7;
    counts[62] = 2;
    QuickSort.sort(counts, residues);
    assertEquals(43, residues[63]);
    assertEquals(59, residues[62]);
    assertEquals(62, residues[61]);
  }
}