package algs13;

import java.text.DecimalFormat;
import stdlib.*;

public class MyLinked2GenericTests {
  //TODO: remove this before you give it to students
  private static void test (String message, java.util.function.Consumer<MyLinked2> function, String list, String expected) {
    MyLinked2 actual = MyLinked2.from (list);
    try {
      function.accept (actual);
    } catch (Throwable e) {
      String exception = e.getClass ().getName ();
      if (! exception.equals (expected)) {
        showError (String.format ("Error: [ %s ].%s: expected=%s, actual=%s", list, message, expected, exception));
        e.printStackTrace (); // for debugging
      }
      return;
    }
    checkInvariants (message, actual);
    if (!expected.equals (actual.toString ())) {
      // If you want to stop execution on an error, replace "StdOut.println" with "throw new Error"
      showError (String.format ("Error: [ %s ].%s: expected=%s, actual=%s", list, message, expected, actual.toString ()));
    }
  }
  public static void main (String[] args) {
    test ("delete(0)", list -> list.delete (0), "", "java.lang.IllegalArgumentException");
    test ("delete(0)", list -> list.delete(-1), "11 21 31", "java.lang.IllegalArgumentException");
    test ("delete(0)", list -> list.delete (3), "11 21 31", "java.lang.IllegalArgumentException");
    test ("delete(0)", list -> list.delete (0), "11", "[ ]");
    test ("delete(0)", list -> list.delete (0), "11 21 31 41", "[ 21 31 41 ]");
    test ("delete(1)", list -> list.delete (1), "11 21 31 41", "[ 11 31 41 ]");
    test ("delete(2)", list -> list.delete (2), "11 21 31 41", "[ 11 21 41 ]");
    test ("delete(3)", list -> list.delete (3), "11 21 31 41", "[ 11 21 31 ]");
    test ("delete(0)", list -> list.delete (0), "11 21 31 41 51", "[ 21 31 41 51 ]");
    test ("delete(1)", list -> list.delete (1), "11 21 31 41 51", "[ 11 31 41 51 ]");
    test ("delete(2)", list -> list.delete (2), "11 21 31 41 51", "[ 11 21 41 51 ]");
    test ("delete(3)", list -> list.delete (3), "11 21 31 41 51", "[ 11 21 31 51 ]");
    test ("delete(4)", list -> list.delete (4), "11 21 31 41 51", "[ 11 21 31 41 ]");   
    test ("reverse", MyLinked2::reverse, "", "[ ]");
    test ("reverse", MyLinked2::reverse, "11", "[ 11 ]");
    test ("reverse", MyLinked2::reverse, "11 21", "[ 21 11 ]");
    test ("reverse", MyLinked2::reverse, "11 21 31", "[ 31 21 11 ]");
    test ("reverse", MyLinked2::reverse, "11 21 31 41", "[ 41 31 21 11 ]");
    test ("reverse", MyLinked2::reverse, "11 21 31 41 51", "[ 51 41 31 21 11 ]");
    test ("remove(5)", list -> list.remove (5), "", "[ ]");
    test ("remove(5)", list -> list.remove (5), "5", "[ ]");
    test ("remove(5)", list -> list.remove (5), "5 5", "[ ]");
    test ("remove(5)", list -> list.remove (5), "5 5 5", "[ ]");
    test ("remove(5)", list -> list.remove (5), "11", "[ 11 ]");
    test ("remove(5)", list -> list.remove (5), "11 21", "[ 11 21 ]");
    test ("remove(5)", list -> list.remove (5), "11 21 31", "[ 11 21 31 ]");
    test ("remove(5)", list -> list.remove (5), "5 11 21 31 41", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "5 5 11 21 31 41", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "5 5 5 11 21 31 41", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "11 21 31 41 5", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "11 21 31 41 5 5", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "11 21 31 41 5 5 5", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "11 21 5 31 41", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "11 21 5 5 31 41", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "11 21 5 5 5 31 41", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "5 11 21 31 41", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "5 5 11 21 31 41", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "5 5 5 11 21 31 41", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "11 21 31 41 5", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "11 21 31 41 5 5", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "11 21 31 41 5 5 5", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "11 21 5 31 41", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "11 21 5 5 31 41", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "11 21 5 5 5 31 41", "[ 11 21 31 41 ]");
    test ("remove(5)", list -> list.remove (5), "5 5 5 11 5 5 21 5 31 5 5 41 5 5 5", "[ 11 21 31 41 ]");
    test ("remove(5.1)", list -> list.remove (5.1), "5.1 5.1 5.1 5 11 5.1 5.1 21 5.1 31 5.1 5.1 41 5.1 5.1 5.1", "[ 5 11 21 31 41 ]");
    
    // What follows is an example of random testing. 
    // Generating good random tests is tricky!
    // The test input and expected response are generated together.
    int NUM_TESTS = 100;
    int MAX_LENGTH = 200;
    DecimalFormat format = new DecimalFormat ("#.###");
    for (int i=0; i<NUM_TESTS; i++) {
      StringBuilder list = new StringBuilder ();
      StringBuilder expected = new StringBuilder ("[ ");
      int length = StdRandom.uniform (MAX_LENGTH);
      double item = StdRandom.uniform ();
      for (int j=0; j<length; j++) {
        boolean makeItem = StdRandom.uniform () < .33;
        if (makeItem) {
          list.append (item); 
          list.append (" ");
        } else {
          double num = StdRandom.uniform ();
          list.append (num); 
          list.append (" ");
          expected.append (format.format (num));
          expected.append (" ");
        }       
      }
      expected.append ("]");
      test (String.format ("remove(%f)", item), li -> li.remove (item), list.toString (), expected.toString ());
    }   
    StdOut.println ("Finished tests");
  }
  
  
  static void showError (String message) {
    Trace.draw ();
    StdOut.println (message);
    //throw new Error (); // stops execution
  }
  private static void checkInvariants (String message, MyLinked2 list) {
    MyLinked2.Node x = list.first;
    int N = list.N;
    for (int i = 0; i < N; i++) {
      if (x == null) {
        showError (String.format ("%s: Expected %d nodes, but got less.", message, N));
      }
      x = x.next;
    }
    if (x != null) {
      showError (String.format ("%s: Expected %d nodes, but got more.", message, N));
    }
  }
  private static void check (String message, MyLinked2 actual, String expected) {
    checkInvariants (message, actual);
    if (!expected.equals (actual.toString ())) {
      showError (String.format ("%s: expected=%s, actual=%s", message, expected, actual.toString ()));
    }
  }
}