package sorters;

import static org.junit.Assert.*;

import org.junit.Before;
import org.junit.Test;

import java.util.ArrayList;
import java.util.Collections;
import java.util.function.*;

public class SorterTest {
	
	ArrayList<Supplier<Sorter<Integer>>> sorters;
	
	@Before
	public void setup() {
		sorters = new ArrayList<>();
		sorters.add(GnomeSorter<Integer>::new);
		sorters.add(InsertionSorter<Integer>::new);
		sorters.add(HeapSorter<Integer>::new);
		sorters.add(MergeSorter<Integer>::new);
		sorters.add(QuickSorter<Integer>::new);
	}
	
	public ArrayList<Integer> generateScrambled(int range, int duplicates) {
		ArrayList<Integer> result = new ArrayList<>();
		for (int i = 0; i < range; i++) {
			for (int j = 0; j < duplicates; j++) {
				result.add(i);
			}
		}
		Collections.shuffle(result);
		return result;
	}
	
	public boolean isSorted(ArrayList<Integer> target) {
		for (int i = 1; i < target.size(); i++) {
			if (target.get(i) < target.get(i-1)) {
				return false;
			}
		}
		return true;
	}
	
	public void testSorter(Sorter<Integer> sorter, ArrayList<Integer> target) {
		ArrayList<Integer> copy = copy(target);
		sorter.sortAlgorithm(copy);
		if (!isSorted(copy)) {
			System.out.println("Algorithm: " + sorter.getClass().getName());
			System.out.print("Original: ");
			show(target);
			System.out.print("Failure:  ");
			show(copy);
			fail("Failed to sort");
		}
		testSettings(sorter, target);
	}
	
	public void testSettings(Sorter<Integer> sorter, ArrayList<Integer> target) {
		ArrayList<Integer> copy = copy(target);
		for (Setting<Integer> s: sorter) {
			s.set(copy);
		}
		assertTrue(isSorted(copy));
	}
	
	public static <T extends Comparable<T>> void show(ArrayList<T> target) {
		for (T t: target) {
			System.out.print(t + " ");
		}
		System.out.println();
	}
	
	public void testAll(ArrayList<Integer> target) {
		for (Supplier<Sorter<Integer>> supplier: sorters) {
			Sorter<Integer> sorter = supplier.get();
			testSorter(sorter, target);
		}
	}
	
	public static ArrayList<Integer> copy(ArrayList<Integer> src) {
		ArrayList<Integer> result = new ArrayList<Integer>();
		result.addAll(src);
		return result;
	}

	@Test
	public void test1() {
		ArrayList<Integer> target = generateScrambled(10, 1);
		testAll(target);
	}

	@Test
	public void test2() {
		ArrayList<Integer> target = generateScrambled(10, 2);
		testAll(target);
	}
	
	@Test
	public void test3() {
		ArrayList<Integer> target = generateScrambled(30, 3);
		testAll(target);
	}
}