package sort

import (
	"testing"
)

// Test the mergesort and deduplication with a predefined set of slices.
func TestSortAndDedup(t *testing.T) {
	to_sort := [][]int{
		{},
		{7},
		{1, 4, 5, 6, 3, 2},
		{1, 2, 3, 4, 5, 6, 7},
		{1, 1, 1, 3, 3, 2, 1},
		{84, 32, 32, 7, 1, 2, 1},
		{1, 3, 5, 5, 7, 8, 10, 17, 19, 24, 27, 34, 76, 1, 1, 2, 3, 5, 8, 13, 21},
		{1, 3, 5, 5, 7, 8, 10, 17, 19, 24, 27, 34, 76, 1, 1, 2, 3, 5, 8, 13, 21, 1, 3, 5, 5, 7, 8, 10, 17, 19, 24, 27, 34, 76, 1, 1, 2, 3, 5, 8, 13, 21, 1, 3, 5, 5, 7, 8, 10, 17, 19, 24, 27, 34, 76, 1, 1, 2},
	}

	result := [][]int{
		{},
		{7},
		{1, 2, 3, 4, 5, 6},
		{1, 2, 3, 4, 5, 6, 7},
		{1, 2, 3},
		{1, 2, 7, 32, 84},
		{1, 2, 3, 5, 7, 8, 10, 13, 17, 19, 21, 24, 27, 34, 76},
		{1, 2, 3, 5, 7, 8, 10, 13, 17, 19, 21, 24, 27, 34, 76},
	}

	for i := range to_sort {
		sorted, _ := SortedAndDedup(make(chan bool, 1), to_sort[i])
		if slice_equal(sorted, result[i]) != true {
			t.Errorf("Failure in sorting + dedup, expected %s got %s", result[i], sorted)
		}
	}

}

// Test the mergesort with a predefined set of slices.
func TestSort(t *testing.T) {
	// ok
	to_sort := [][]int{
		{},
		{7},
		{1, 4, 5, 6, 3, 2},
		{1, 2, 3, 4, 5, 6, 7},
		{1, 1, 1, 3, 3, 2, 1},
		{84, 32, 32, 7, 1, 2, 1},
		{1, 3, 5, 5, 7, 8, 10, 17, 19, 24, 27, 34, 76, 1, 1, 2, 3, 5, 8, 13, 21},
	}

	result := [][]int{
		{},
		{7},
		{1, 2, 3, 4, 5, 6},
		{1, 2, 3, 4, 5, 6, 7},
		{1, 1, 1, 1, 2, 3, 3},
		{1, 1, 2, 7, 32, 32, 84},
		{1, 1, 1, 2, 3, 3, 5, 5, 5, 7, 8, 8, 10, 13, 17, 19, 21, 24, 27, 34, 76},
	}

	for i := range to_sort {
		sorted, _ := Mergesort(make(chan bool, 1), to_sort[i])
		if slice_equal(sorted, result[i]) != true {
			t.Errorf("Failure in sorting, expected %s got %s", result[i], sorted)
		}
	}
}

// Helper function to compare int slices for equality.
func slice_equal(s1 []int, s2 []int) bool {
	if s1 == nil && s2 == nil {
		return true
	}

	if s1 == nil || s2 == nil {
		return false
	}

	if len(s1) != len(s2) {
		return false
	}

	for i := range s1 {
		if s1[i] != s2[i] {
			return false
		}
	}

	return true
}