import java.util.function.Predicate;
import static org.junit.jupiter.api.Assertions.*;
import org.junit.jupiter.api.Test;

/**
 * Some of SamR's tests of implementations of the directory interface.
 */
class SamDirectoryTests {

  // +-----------+---------------------------------------------------
  // | Constants |
  // +-----------+

  /**
   * Some fruits Mostly taken from https://simple.wikipedia.org/wiki/List_of_fruits. Some are fake.
   */
  static String[] fruits =
      {"Apple", "Banana", "Cherry", "Durian", "Elderberry", "Fig", "Grape",
          "Huckleberry", "Ice", "Jackfruit", "Kiwi", "Lime", "Melon",
          "Nectarine", "Orange", "Papaya", "Quince", "Raspberry", "Strawberry",
          "Tamarind", "Ugli", "Vfruit", "Whitefruit", "Xuit", "Yuzu", "Zuit"};

  /**
   * Some names. Mostly taken from https://en.wikipedia.org/wiki/Unisex_name
   */
  static String[] names = {"Addison", "Blake", "Casey", "Delaney", "Elliot",
      "Flynn", "Gale", "Hadley", "Ivy", "Jody", "Kelly", "Lesley", "Madison",
      "Nash", "Odell", "Paige", "Quinn", "Reed", "Scout", "Tatum", "U",
      "Valentine", "Wallis", "Xavy", "You", "Zane"};

  // +---------+-----------------------------------------------------
  // | Globals |
  // +---------+

  Directory dir;

  // +-----------+---------------------------------------------------
  // | Utilities |
  // +-----------+

  /**
   * Set up the directory.
   */
  void setup() {
    dir = new Directory();
  } // setup

  /**
   * Set a bunch of strings to the directory.
   */
  void setValues(Directory dir, String[] values) {
    for (String str : values) {
      String screen = str.substring(0, 1);
      dir.set(screen, str);
    } // for
  } // setValues

  /**
   * Check that the directory contains a set of strings.
   */
  void checkValues(String[] strings, Directory dir) throws Exception {
    for (String str : strings) {
      assertEquals(str, dir.get(str.substring(0, 1)));
    } // for
  } // checkValues

  /**
   * Check that the directory contains a set of strings that meet a particular predicate.
   */
  void checkValues(String[] strings, Predicate<? super String> pred,
      Directory dir) throws Exception {
    for (String str : strings) {
      String screen = str.substring(0, 1);
      if (pred.test(screen)) {
        assertEquals(str, dir.get(screen));
      } else {
        assertThrows(java.lang.Exception.class, () -> dir.get(screen));
      } // if/else
    } // for
  } // checkValues

  // +-------+-------------------------------------------------------
  // | Tests |
  // +-------+

  @Test
  void testBasic() throws Exception {
    setup();
    setValues(dir, fruits);
    checkValues(fruits, dir);
  } // testBasic()

  @Test
  void testBackwards() throws Exception {
    setup();
    String[] stiurf = new String[fruits.length];
    for (int i = 0; i < fruits.length; i++) {
      stiurf[i] = fruits[fruits.length - 1 - i];
    } // for
    setValues(dir, stiurf);
    checkValues(fruits, dir);
  } // testBackwards()

  @Test
  void testRandomized() throws Exception {
    for (int trials = 0; trials < 5; trials++) {
      setup();
      String[] temp = fruits.clone();
      TestUtils.randomlyPermute(temp);
      setValues(dir, temp);
      checkValues(fruits, dir);
    } // for
  } // testRandomized()

  @Test
  void testReplacement() throws Exception {
    setup();
    setValues(dir, fruits);
    setValues(dir, names);
    checkValues(names, dir);

    setValues(dir, fruits);
    checkValues(fruits, dir);

    String[] temp = names.clone();
    TestUtils.randomlyPermute(temp);
    setValues(dir, temp);
    checkValues(names, dir);

    temp = fruits.clone();
    TestUtils.randomlyPermute(temp);
    setValues(dir, temp);
    checkValues(fruits, dir);
  } // testReplacement()

  @Test
  void testRemoveScreen() throws Exception {
    // Note: This needs refactoring.

    setup();
    setValues(dir, fruits);

    // Remove some entries
    TestUtils.remove(dir.screenNames(), (str) -> "FGHTUVWY".contains(str));
    checkValues(fruits, (str) -> (!"FGHTUVWY".contains(str)), dir);

    // Add them back in
    setValues(dir, fruits);
    checkValues(fruits, dir);

    // Remove entries at the front (and in the middle)
    TestUtils.remove(dir.screenNames(), (str) -> "ABCDELMNOP".contains(str));
    checkValues(fruits, (str) -> (!"ABCDELMNOP".contains(str)), dir);

    // Add them back in
    setValues(dir, fruits);
    checkValues(fruits, dir);

    // Remove entries at the end
    TestUtils.remove(dir.screenNames(), (str) -> "WXYZ".contains(str));
    checkValues(fruits, (str) -> (!"WXYZ".contains(str)), dir);

    // Add them back in
    setValues(dir, fruits);
    checkValues(fruits, dir);

    // Multiple removes
    TestUtils.remove(dir.screenNames(), (str) -> "LMNOP".contains(str));
    TestUtils.remove(dir.screenNames(), (str) -> "ABC".contains(str));
    TestUtils.remove(dir.screenNames(), (str) -> "EFG".contains(str));
    TestUtils.remove(dir.screenNames(), (str) -> "XYZ".contains(str));
    checkValues(fruits, (str) -> (!"ABCEFGLMNOPXYZ".contains(str)), dir);

    // Add them back in
    setValues(dir, fruits);
    checkValues(fruits, dir);
  } // testRemoveScreen()

  @Test
  void testRemoveRealNames() throws Exception {
    setup();
    setValues(dir, fruits);

    String[] screens = {"A", "B", "C", "E", "L", "O", "P", "Q", "X", "Y", "Z"};

    // Update a bunch of values so that they have the same name.
    for (String str : screens) {
      dir.set(str, "REMOVE");
    }

    // Remove them
    TestUtils.remove(dir.realNames(), (name) -> "REMOVE".equals(name));

    // Verify that the are no longer there
    for (String str : screens) {
      assertThrows(java.lang.Exception.class, () -> dir.get(str));
    }

    // Verify that everything else is still there
    checkValues(fruits, (name) -> (!"ABCELOPQXYZ".contains(name)), dir);

    // And that we can put everything back in
    setValues(dir, fruits);
    checkValues(fruits, dir);

  } // testRemoveRealNames()

} // SamDirectoryTests