package roaring

import (
	"bytes"
	"log"
	"math/rand"
	"strconv"
	"testing"
	"unsafe"

	"github.com/stretchr/testify/assert"
	"github.com/willf/bitset"
)

func TestCloneOfCOW(t *testing.T) {
	rb1 := NewBitmap()
	rb1.SetCopyOnWrite(true)
	rb1.Add(10)
	rb1.Add(12)
	rb1.Remove(12)

	rb2 := rb1.Clone()

	rb3 := rb1.Clone()

	rb2.Remove(10)

	rb3.AddRange(100, 200)

	assert.NotEmpty(t, rb2.IsEmpty())
	assert.EqualValues(t, 100+1, rb3.GetCardinality())
	assert.True(t, rb1.Contains(10))
	assert.EqualValues(t, 1, rb1.GetCardinality())
}

func TestRoaringBitmapBitmapOfCOW(t *testing.T) {
	array := []uint32{5580, 33722, 44031, 57276, 83097}
	bmp := BitmapOf(array...)
	bmp.SetCopyOnWrite(true)

	assert.EqualValues(t, len(array), bmp.GetCardinality())
}

func TestRoaringBitmapAddCOW(t *testing.T) {
	array := []uint32{5580, 33722, 44031, 57276, 83097}
	bmp := New()
	bmp.SetCopyOnWrite(true)
	for _, v := range array {
		bmp.Add(v)
	}

	assert.EqualValues(t, len(array), bmp.GetCardinality())
}

func TestRoaringBitmapAddManyCOW(t *testing.T) {
	array := []uint32{5580, 33722, 44031, 57276, 83097}
	bmp := NewBitmap()
	bmp.SetCopyOnWrite(true)

	bmp.AddMany(array)

	assert.EqualValues(t, len(array), bmp.GetCardinality())
}

// https://github.com/RoaringBitmap/roaring/issues/64
func TestFlip64COW(t *testing.T) {
	bm := New()
	bm.SetCopyOnWrite(true)

	bm.AddInt(0)
	bm.Flip(1, 2)
	i := bm.Iterator()

	assert.False(t, i.Next() != 0 || i.Next() != 1 || i.HasNext())
}

// https://github.com/RoaringBitmap/roaring/issues/64
func TestFlip64OffCOW(t *testing.T) {
	bm := New()
	bm.SetCopyOnWrite(true)

	bm.AddInt(10)
	bm.Flip(11, 12)
	i := bm.Iterator()

	assert.False(t, i.Next() != 10 || i.Next() != 11 || i.HasNext())
}

func TestStringerCOW(t *testing.T) {
	v := NewBitmap()
	v.SetCopyOnWrite(true)
	for i := uint32(0); i < 10; i++ {
		v.Add(i)
	}

	assert.Equal(t, "{0,1,2,3,4,5,6,7,8,9}", v.String())

	v.RunOptimize()

	assert.Equal(t, "{0,1,2,3,4,5,6,7,8,9}", v.String())
}

func TestFastCardCOW(t *testing.T) {
	bm := NewBitmap()
	bm.SetCopyOnWrite(true)
	bm.Add(1)
	bm.AddRange(21, 260000)

	bm2 := NewBitmap()
	bm2.SetCopyOnWrite(true)
	bm2.Add(25)

	assert.EqualValues(t, 1, bm2.AndCardinality(bm))
	assert.Equal(t, bm.GetCardinality(), bm2.OrCardinality(bm))
	assert.EqualValues(t, 1, bm.AndCardinality(bm2))
	assert.Equal(t, bm.GetCardinality(), bm.OrCardinality(bm2))
	assert.EqualValues(t, 1, bm2.AndCardinality(bm))
	assert.Equal(t, bm.GetCardinality(), bm2.OrCardinality(bm))

	bm.RunOptimize()

	assert.EqualValues(t, 1, bm2.AndCardinality(bm))
	assert.Equal(t, bm.GetCardinality(), bm2.OrCardinality(bm))
	assert.EqualValues(t, 1, bm.AndCardinality(bm2))
	assert.Equal(t, bm.GetCardinality(), bm.OrCardinality(bm2))
	assert.EqualValues(t, 1, bm2.AndCardinality(bm))
	assert.Equal(t, bm.GetCardinality(), bm2.OrCardinality(bm))
}

func TestIntersects1COW(t *testing.T) {
	bm := NewBitmap()
	bm.SetCopyOnWrite(true)
	bm.Add(1)
	bm.AddRange(21, 26)

	bm2 := NewBitmap()
	bm2.SetCopyOnWrite(true)
	bm2.Add(25)

	assert.True(t, bm2.Intersects(bm))

	bm.Remove(25)
	assert.False(t, bm2.Intersects(bm))

	bm.AddRange(1, 100000)
	assert.True(t, bm2.Intersects(bm))
}

func TestRangePanicCOW(t *testing.T) {
	bm := NewBitmap()
	bm.SetCopyOnWrite(true)
	bm.Add(1)
	bm.AddRange(21, 26)
	bm.AddRange(9, 14)
	bm.AddRange(11, 16)
}

func TestRangeRemovalCOW(t *testing.T) {
	bm := NewBitmap()
	bm.SetCopyOnWrite(true)
	bm.Add(1)
	bm.AddRange(21, 26)
	bm.AddRange(9, 14)
	bm.RemoveRange(11, 16)
	bm.RemoveRange(1, 26)

	assert.EqualValues(t, 0, bm.GetCardinality())

	bm.AddRange(1, 10000)
	assert.EqualValues(t, 10000-1, bm.GetCardinality())

	bm.RemoveRange(1, 10000)
	assert.EqualValues(t, 0, bm.GetCardinality())
}

func TestRangeRemovalFromContentCOW(t *testing.T) {
	bm := NewBitmap()
	bm.SetCopyOnWrite(true)
	for i := 100; i < 10000; i++ {
		bm.AddInt(i * 3)
	}
	bm.AddRange(21, 26)
	bm.AddRange(9, 14)
	bm.RemoveRange(11, 16)
	bm.RemoveRange(0, 30000)

	assert.EqualValues(t, 0, bm.GetCardinality())
}

func TestFlipOnEmptyCOW(t *testing.T) {
	t.Run("TestFlipOnEmpty in-place", func(t *testing.T) {
		bm := NewBitmap()
		bm.SetCopyOnWrite(true)
		bm.Flip(0, 10)
		c := bm.GetCardinality()

		assert.EqualValues(t, 10, c)
	})

	t.Run("TestFlipOnEmpty, generating new result", func(t *testing.T) {
		bm := NewBitmap()
		bm.SetCopyOnWrite(true)
		bm = Flip(bm, 0, 10)
		c := bm.GetCardinality()

		assert.EqualValues(t, 10, c)
	})
}

func TestBitmapRankCOW(t *testing.T) {
	for N := uint32(1); N <= 1048576; N *= 2 {
		t.Run("rank tests"+strconv.Itoa(int(N)), func(t *testing.T) {
			for gap := uint32(1); gap <= 65536; gap *= 2 {
				rb1 := NewBitmap()
				rb1.SetCopyOnWrite(true)
				for x := uint32(0); x <= N; x += gap {
					rb1.Add(x)
				}
				for y := uint32(0); y <= N; y++ {
					if rb1.Rank(y) != uint64((y+1+gap-1)/gap) {
						assert.Equal(t, (y+1+gap-1)/gap, rb1.Rank(y))
					}
				}
			}
		})
	}
}

func TestBitmapSelectCOW(t *testing.T) {
	for N := uint32(1); N <= 1048576; N *= 2 {
		t.Run("rank tests"+strconv.Itoa(int(N)), func(t *testing.T) {
			for gap := uint32(1); gap <= 65536; gap *= 2 {
				rb1 := NewBitmap()
				rb1.SetCopyOnWrite(true)
				for x := uint32(0); x <= N; x += gap {
					rb1.Add(x)
				}
				for y := uint32(0); y <= N/gap; y++ {
					expectedInt := y * gap
					i, err := rb1.Select(y)
					if err != nil {
						t.Fatal(err)
					}

					if i != expectedInt {
						assert.Equal(t, expectedInt, i)
					}
				}
			}
		})
	}
}

// some extra tests
func TestBitmapExtraCOW(t *testing.T) {
	for N := uint32(1); N <= 65536; N *= 2 {
		t.Run("extra tests"+strconv.Itoa(int(N)), func(t *testing.T) {
			for gap := uint32(1); gap <= 65536; gap *= 2 {
				bs1 := bitset.New(0)
				rb1 := NewBitmap()
				rb1.SetCopyOnWrite(true)

				for x := uint32(0); x <= N; x += gap {
					bs1.Set(uint(x))
					rb1.Add(x)
				}

				assert.EqualValues(t, rb1.GetCardinality(), bs1.Count())
				assert.True(t, equalsBitSet(bs1, rb1))

				for offset := uint32(1); offset <= gap; offset *= 2 {
					bs2 := bitset.New(0)
					rb2 := NewBitmap()
					rb2.SetCopyOnWrite(true)

					for x := uint32(0); x <= N; x += gap {
						bs2.Set(uint(x + offset))
						rb2.Add(x + offset)
					}

					assert.EqualValues(t, rb2.GetCardinality(), bs2.Count())
					assert.True(t, equalsBitSet(bs2, rb2))

					clonebs1 := bs1.Clone()
					clonebs1.InPlaceIntersection(bs2)
					if !equalsBitSet(clonebs1, And(rb1, rb2)) {
						v := rb1.Clone()
						v.And(rb2)

						assert.True(t, equalsBitSet(clonebs1, v))
					}

					// testing OR
					clonebs1 = bs1.Clone()
					clonebs1.InPlaceUnion(bs2)

					assert.True(t, equalsBitSet(clonebs1, Or(rb1, rb2)))

					// testing XOR
					clonebs1 = bs1.Clone()
					clonebs1.InPlaceSymmetricDifference(bs2)

					assert.True(t, equalsBitSet(clonebs1, Xor(rb1, rb2)))

					//testing NOTAND
					clonebs1 = bs1.Clone()
					clonebs1.InPlaceDifference(bs2)

					assert.True(t, equalsBitSet(clonebs1, AndNot(rb1, rb2)))
				}
			}
		})
	}
}

func TestBitmapCOW(t *testing.T) {
	t.Run("Test Contains", func(t *testing.T) {
		rbm1 := NewBitmap()
		rbm1.SetCopyOnWrite(true)
		for k := 0; k < 1000; k++ {
			rbm1.AddInt(17 * k)
		}
		for k := 0; k < 17*1000; k++ {
			assert.Equal(t, k/17*17 == k, rbm1.ContainsInt(k))
		}
	})

	t.Run("Test Clone", func(t *testing.T) {
		rb1 := NewBitmap()
		rb1.SetCopyOnWrite(true)
		rb1.Add(10)

		rb2 := rb1.Clone()
		rb2.Remove(10)

		assert.True(t, rb1.Contains(10))
	})

	t.Run("Test ANDNOT4", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb2 := NewBitmap()
		rb2.SetCopyOnWrite(true)

		for i := 0; i < 200000; i += 4 {
			rb2.AddInt(i)
		}
		for i := 200000; i < 400000; i += 14 {
			rb2.AddInt(i)
		}

		off := AndNot(rb2, rb)
		andNotresult := AndNot(rb, rb2)

		assert.True(t, rb.Equals(andNotresult))
		assert.True(t, rb2.Equals(off))

		rb2.AndNot(rb)
		assert.True(t, rb2.Equals(off))
	})

	t.Run("Test AND", func(t *testing.T) {
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		for k := 0; k < 4000; k++ {
			rr.AddInt(k)
		}
		rr.Add(100000)
		rr.Add(110000)
		rr2 := NewBitmap()
		rr2.SetCopyOnWrite(true)
		rr2.Add(13)
		rrand := And(rr, rr2)
		array := rrand.ToArray()

		assert.Equal(t, 1, len(array))
		assert.EqualValues(t, 13, array[0])

		rr.And(rr2)
		array = rr.ToArray()

		assert.Equal(t, 1, len(array))
		assert.EqualValues(t, 13, array[0])
	})

	t.Run("Test AND 2", func(t *testing.T) {
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		for k := 4000; k < 4256; k++ {
			rr.AddInt(k)
		}
		for k := 65536; k < 65536+4000; k++ {
			rr.AddInt(k)
		}
		for k := 3 * 65536; k < 3*65536+9000; k++ {
			rr.AddInt(k)
		}
		for k := 4 * 65535; k < 4*65535+7000; k++ {
			rr.AddInt(k)
		}
		for k := 6 * 65535; k < 6*65535+10000; k++ {
			rr.AddInt(k)
		}
		for k := 8 * 65535; k < 8*65535+1000; k++ {
			rr.AddInt(k)
		}
		for k := 9 * 65535; k < 9*65535+30000; k++ {
			rr.AddInt(k)
		}

		rr2 := NewBitmap()
		rr2.SetCopyOnWrite(true)
		for k := 4000; k < 4256; k++ {
			rr2.AddInt(k)
		}
		for k := 65536; k < 65536+4000; k++ {
			rr2.AddInt(k)
		}
		for k := 3*65536 + 2000; k < 3*65536+6000; k++ {
			rr2.AddInt(k)
		}
		for k := 6 * 65535; k < 6*65535+1000; k++ {
			rr2.AddInt(k)
		}
		for k := 7 * 65535; k < 7*65535+1000; k++ {
			rr2.AddInt(k)
		}
		for k := 10 * 65535; k < 10*65535+5000; k++ {
			rr2.AddInt(k)
		}
		correct := And(rr, rr2)
		rr.And(rr2)

		assert.True(t, correct.Equals(rr))
	})

	t.Run("Test AND 2", func(t *testing.T) {
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		for k := 0; k < 4000; k++ {
			rr.AddInt(k)
		}
		rr.AddInt(100000)
		rr.AddInt(110000)
		rr2 := NewBitmap()
		rr2.SetCopyOnWrite(true)
		rr2.AddInt(13)

		rrand := And(rr, rr2)
		array := rrand.ToArray()

		assert.Equal(t, 1, len(array))
		assert.EqualValues(t, 13, array[0])
	})

	t.Run("Test AND 3a", func(t *testing.T) {
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		rr2 := NewBitmap()
		rr2.SetCopyOnWrite(true)
		for k := 6 * 65536; k < 6*65536+10000; k++ {
			rr.AddInt(k)
		}
		for k := 6 * 65536; k < 6*65536+1000; k++ {
			rr2.AddInt(k)
		}
		result := And(rr, rr2)

		assert.EqualValues(t, 1000, result.GetCardinality())
	})

	t.Run("Test AND 3", func(t *testing.T) {
		var arrayand [11256]uint32
		//393,216
		pos := 0
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		for k := 4000; k < 4256; k++ {
			rr.AddInt(k)
		}
		for k := 65536; k < 65536+4000; k++ {
			rr.AddInt(k)
		}
		for k := 3 * 65536; k < 3*65536+1000; k++ {
			rr.AddInt(k)
		}
		for k := 3*65536 + 1000; k < 3*65536+7000; k++ {
			rr.AddInt(k)
		}
		for k := 3*65536 + 7000; k < 3*65536+9000; k++ {
			rr.AddInt(k)
		}
		for k := 4 * 65536; k < 4*65536+7000; k++ {
			rr.AddInt(k)
		}
		for k := 8 * 65536; k < 8*65536+1000; k++ {
			rr.AddInt(k)
		}
		for k := 9 * 65536; k < 9*65536+30000; k++ {
			rr.AddInt(k)
		}

		rr2 := NewBitmap()
		rr2.SetCopyOnWrite(true)
		for k := 4000; k < 4256; k++ {
			rr2.AddInt(k)
			arrayand[pos] = uint32(k)
			pos++
		}
		for k := 65536; k < 65536+4000; k++ {
			rr2.AddInt(k)
			arrayand[pos] = uint32(k)
			pos++
		}
		for k := 3*65536 + 1000; k < 3*65536+7000; k++ {
			rr2.AddInt(k)
			arrayand[pos] = uint32(k)
			pos++
		}
		for k := 6 * 65536; k < 6*65536+10000; k++ {
			rr.AddInt(k)
		}
		for k := 6 * 65536; k < 6*65536+1000; k++ {
			rr2.AddInt(k)
			arrayand[pos] = uint32(k)
			pos++
		}

		for k := 7 * 65536; k < 7*65536+1000; k++ {
			rr2.AddInt(k)
		}
		for k := 10 * 65536; k < 10*65536+5000; k++ {
			rr2.AddInt(k)
		}
		rrand := And(rr, rr2)

		arrayres := rrand.ToArray()
		ok := true
		for i := range arrayres {
			if i < len(arrayand) {
				if arrayres[i] != arrayand[i] {
					log.Println(i, arrayres[i], arrayand[i])
					ok = false
				}
			} else {
				log.Println('x', arrayres[i])
				ok = false
			}
		}

		assert.Equal(t, len(arrayres), len(arrayand))
		assert.True(t, ok)
	})

	t.Run("Test AND 4", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb2 := NewBitmap()
		rb2.SetCopyOnWrite(true)

		for i := 0; i < 200000; i += 4 {
			rb2.AddInt(i)
		}
		for i := 200000; i < 400000; i += 14 {
			rb2.AddInt(i)
		}
		//TODO: Bitmap.And(bm,bm2)
		andresult := And(rb, rb2)
		off := And(rb2, rb)

		assert.True(t, andresult.Equals(off))
		assert.EqualValues(t, 0, andresult.GetCardinality())

		for i := 500000; i < 600000; i += 14 {
			rb.AddInt(i)
		}
		for i := 200000; i < 400000; i += 3 {
			rb2.AddInt(i)
		}
		andresult2 := And(rb, rb2)

		assert.EqualValues(t, 0, andresult.GetCardinality())
		assert.EqualValues(t, 0, andresult2.GetCardinality())

		for i := 0; i < 200000; i += 4 {
			rb.AddInt(i)
		}
		for i := 200000; i < 400000; i += 14 {
			rb.AddInt(i)
		}

		assert.EqualValues(t, 0, andresult.GetCardinality())

		rc := And(rb, rb2)
		rb.And(rb2)

		assert.Equal(t, rb.GetCardinality(), rc.GetCardinality())
	})

	t.Run("ArrayContainerCardinalityTest", func(t *testing.T) {
		ac := newArrayContainer()
		for k := uint16(0); k < 100; k++ {
			ac.iadd(k)
			assert.EqualValues(t, k+1, ac.getCardinality())
		}
		for k := uint16(0); k < 100; k++ {
			ac.iadd(k)
			assert.EqualValues(t, 100, ac.getCardinality())
		}
	})

	t.Run("or test", func(t *testing.T) {
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		for k := 0; k < 4000; k++ {
			rr.AddInt(k)
		}
		rr2 := NewBitmap()
		rr2.SetCopyOnWrite(true)
		for k := 4000; k < 8000; k++ {
			rr2.AddInt(k)
		}
		result := Or(rr, rr2)
		assert.Equal(t, rr.GetCardinality()+rr2.GetCardinality(), result.GetCardinality())
	})

	t.Run("basic test", func(t *testing.T) {
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		var a [4002]uint32
		pos := 0
		for k := 0; k < 4000; k++ {
			rr.AddInt(k)
			a[pos] = uint32(k)
			pos++
		}
		rr.AddInt(100000)
		a[pos] = 100000
		pos++
		rr.AddInt(110000)
		a[pos] = 110000
		pos++
		array := rr.ToArray()
		ok := true
		for i := range a {
			if array[i] != a[i] {
				log.Println("rr : ", array[i], " a : ", a[i])
				ok = false
			}
		}

		assert.Equal(t, len(a), len(array))
		assert.True(t, ok)
	})

	t.Run("BitmapContainerCardinalityTest", func(t *testing.T) {
		ac := newBitmapContainer()
		for k := uint16(0); k < 100; k++ {
			ac.iadd(k)
			assert.EqualValues(t, k+1, ac.getCardinality())
		}
		for k := uint16(0); k < 100; k++ {
			ac.iadd(k)
			assert.EqualValues(t, 100, ac.getCardinality())
		}
	})

	t.Run("BitmapContainerTest", func(t *testing.T) {
		rr := newBitmapContainer()
		rr.iadd(uint16(110))
		rr.iadd(uint16(114))
		rr.iadd(uint16(115))
		var array [3]uint16
		pos := 0
		for itr := rr.getShortIterator(); itr.hasNext(); {
			array[pos] = itr.next()
			pos++
		}

		assert.EqualValues(t, 110, array[0])
		assert.EqualValues(t, 114, array[1])
		assert.EqualValues(t, 115, array[2])
	})

	t.Run("cardinality test", func(t *testing.T) {
		N := 1024
		for gap := 7; gap < 100000; gap *= 10 {
			for offset := 2; offset <= 1024; offset *= 2 {
				rb := NewBitmap()
				rb.SetCopyOnWrite(true)
				for k := 0; k < N; k++ {
					rb.AddInt(k * gap)
					assert.EqualValues(t, k+1, rb.GetCardinality())
				}

				assert.EqualValues(t, N, rb.GetCardinality())

				// check the add of existing values
				for k := 0; k < N; k++ {
					rb.AddInt(k * gap)
					assert.EqualValues(t, N, rb.GetCardinality())
				}

				rb2 := NewBitmap()
				rb2.SetCopyOnWrite(true)

				for k := 0; k < N; k++ {
					rb2.AddInt(k * gap * offset)
					assert.EqualValues(t, k+1, rb2.GetCardinality())
				}

				assert.EqualValues(t, N, rb2.GetCardinality())

				for k := 0; k < N; k++ {
					rb2.AddInt(k * gap * offset)
					assert.EqualValues(t, N, rb2.GetCardinality())
				}
				assert.EqualValues(t, N/offset, And(rb, rb2).GetCardinality())
				assert.EqualValues(t, 2*N-2*N/offset, Xor(rb, rb2).GetCardinality())
				assert.EqualValues(t, 2*N-N/offset, Or(rb, rb2).GetCardinality())
			}
		}
	})

	t.Run("clear test", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		for i := 0; i < 200000; i += 7 {
			// dense
			rb.AddInt(i)
		}
		for i := 200000; i < 400000; i += 177 {
			// sparse
			rb.AddInt(i)
		}

		rb2 := NewBitmap()
		rb2.SetCopyOnWrite(true)
		rb3 := NewBitmap()
		rb3.SetCopyOnWrite(true)
		for i := 0; i < 200000; i += 4 {
			rb2.AddInt(i)
		}
		for i := 200000; i < 400000; i += 14 {
			rb2.AddInt(i)
		}

		rb.Clear()

		assert.EqualValues(t, 0, rb.GetCardinality())
		assert.NotEqual(t, 0, rb2.GetCardinality())

		rb.AddInt(4)
		rb3.AddInt(4)
		andresult := And(rb, rb2)
		orresult := Or(rb, rb2)

		assert.EqualValues(t, 1, andresult.GetCardinality())
		assert.Equal(t, rb2.GetCardinality(), orresult.GetCardinality())

		for i := 0; i < 200000; i += 4 {
			rb.AddInt(i)
			rb3.AddInt(i)
		}
		for i := 200000; i < 400000; i += 114 {
			rb.AddInt(i)
			rb3.AddInt(i)
		}

		arrayrr := rb.ToArray()
		arrayrr3 := rb3.ToArray()
		ok := true
		for i := range arrayrr {
			if arrayrr[i] != arrayrr3[i] {
				ok = false
			}
		}

		assert.Equal(t, len(arrayrr3), len(arrayrr))
		assert.True(t, ok)
	})

	t.Run("constainer factory ", func(t *testing.T) {
		bc1 := newBitmapContainer()
		bc2 := newBitmapContainer()
		bc3 := newBitmapContainer()
		ac1 := newArrayContainer()
		ac2 := newArrayContainer()
		ac3 := newArrayContainer()

		for i := 0; i < 5000; i++ {
			bc1.iadd(uint16(i * 70))
		}
		for i := 0; i < 5000; i++ {
			bc2.iadd(uint16(i * 70))
		}
		for i := 0; i < 5000; i++ {
			bc3.iadd(uint16(i * 70))
		}
		for i := 0; i < 4000; i++ {
			ac1.iadd(uint16(i * 50))
		}
		for i := 0; i < 4000; i++ {
			ac2.iadd(uint16(i * 50))
		}
		for i := 0; i < 4000; i++ {
			ac3.iadd(uint16(i * 50))
		}

		rbc := ac1.clone().(*arrayContainer).toBitmapContainer()
		assert.True(t, validate(rbc, ac1))

		rbc = ac2.clone().(*arrayContainer).toBitmapContainer()
		assert.True(t, validate(rbc, ac2))

		rbc = ac3.clone().(*arrayContainer).toBitmapContainer()
		assert.True(t, validate(rbc, ac3))
	})

	t.Run("flipTest1 ", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb.Flip(100000, 200000) // in-place on empty bitmap
		rbcard := rb.GetCardinality()

		assert.EqualValues(t, rbcard, 100000)

		bs := bitset.New(20000 - 10000)
		for i := uint(100000); i < 200000; i++ {
			bs.Set(i)
		}

		assert.True(t, equalsBitSet(bs, rb))
	})

	t.Run("flipTest1A", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb1 := Flip(rb, 100000, 200000)
		rbcard := rb1.GetCardinality()

		assert.EqualValues(t, rbcard, 100000)
		assert.EqualValues(t, rb.GetCardinality(), 0)

		bs := bitset.New(0)
		assert.True(t, equalsBitSet(bs, rb))

		for i := uint(100000); i < 200000; i++ {
			bs.Set(i)
		}

		assert.True(t, equalsBitSet(bs, rb1))
	})

	t.Run("flipTest2", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb.Flip(100000, 100000)
		rbcard := rb.GetCardinality()

		assert.EqualValues(t, rbcard, 0)

		bs := bitset.New(0)
		assert.True(t, equalsBitSet(bs, rb))
	})

	t.Run("flipTest2A", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb1 := Flip(rb, 100000, 100000)

		rb.AddInt(1)
		rbcard := rb1.GetCardinality()

		assert.EqualValues(t, 0, rbcard)
		assert.EqualValues(t, rb.GetCardinality(), 1)

		bs := bitset.New(0)
		assert.True(t, equalsBitSet(bs, rb1))

		bs.Set(1)
		assert.True(t, equalsBitSet(bs, rb))
	})

	t.Run("flipTest3A", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb.Flip(100000, 200000) // got 100k-199999
		rb.Flip(100000, 199991) // give back 100k-199990
		rbcard := rb.GetCardinality()

		assert.EqualValues(t, 9, rbcard)

		bs := bitset.New(0)
		for i := uint(199991); i < 200000; i++ {
			bs.Set(i)
		}

		assert.True(t, equalsBitSet(bs, rb))
	})

	t.Run("flipTest4A", func(t *testing.T) {
		// fits evenly on both ends
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb.Flip(100000, 200000) // got 100k-199999
		rb.Flip(65536, 4*65536)
		rbcard := rb.GetCardinality()

		// 65536 to 99999 are 1s
		// 200000 to 262143 are 1s: total card

		assert.EqualValues(t, 96608, rbcard)

		bs := bitset.New(0)
		for i := uint(65536); i < 100000; i++ {
			bs.Set(i)
		}
		for i := uint(200000); i < 262144; i++ {
			bs.Set(i)
		}

		assert.True(t, equalsBitSet(bs, rb))
	})

	t.Run("flipTest5", func(t *testing.T) {
		// fits evenly on small end, multiple
		// containers
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb.Flip(100000, 132000)
		rb.Flip(65536, 120000)
		rbcard := rb.GetCardinality()

		// 65536 to 99999 are 1s
		// 120000 to 131999

		assert.EqualValues(t, 46464, rbcard)

		bs := bitset.New(0)
		for i := uint(65536); i < 100000; i++ {
			bs.Set(i)
		}
		for i := uint(120000); i < 132000; i++ {
			bs.Set(i)
		}

		assert.True(t, equalsBitSet(bs, rb))
	})

	t.Run("flipTest6", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb1 := Flip(rb, 100000, 132000)
		rb2 := Flip(rb1, 65536, 120000)
		//rbcard := rb2.GetCardinality()

		bs := bitset.New(0)
		for i := uint(65536); i < 100000; i++ {
			bs.Set(i)
		}
		for i := uint(120000); i < 132000; i++ {
			bs.Set(i)
		}

		assert.True(t, equalsBitSet(bs, rb2))
	})

	t.Run("flipTest6A", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb1 := Flip(rb, 100000, 132000)
		rb2 := Flip(rb1, 99000, 2*65536)
		rbcard := rb2.GetCardinality()

		assert.EqualValues(t, 1928, rbcard)

		bs := bitset.New(0)
		for i := uint(99000); i < 100000; i++ {
			bs.Set(i)
		}
		for i := uint(2 * 65536); i < 132000; i++ {
			bs.Set(i)
		}

		assert.True(t, equalsBitSet(bs, rb2))
	})

	t.Run("flipTest7", func(t *testing.T) {
		// within 1 word, first container
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb.Flip(650, 132000)
		rb.Flip(648, 651)
		rbcard := rb.GetCardinality()

		// 648, 649, 651-131999
		assert.EqualValues(t, 132000-651+2, rbcard)

		bs := bitset.New(0)
		bs.Set(648)
		bs.Set(649)
		for i := uint(651); i < 132000; i++ {
			bs.Set(i)
		}

		assert.True(t, equalsBitSet(bs, rb))
	})

	t.Run("flipTestBig", func(t *testing.T) {
		numCases := 1000
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		bs := bitset.New(0)
		//Random r = new Random(3333);
		checkTime := 2.0

		for i := 0; i < numCases; i++ {
			start := rand.Intn(65536 * 20)
			end := rand.Intn(65536 * 20)
			if rand.Float64() < float64(0.1) {
				end = start + rand.Intn(100)
			}
			rb.Flip(uint64(start), uint64(end))
			if start < end {
				FlipRange(start, end, bs) // throws exception
			}
			// otherwise
			// insert some more ANDs to keep things sparser
			if rand.Float64() < 0.2 {
				mask := NewBitmap()
				mask.SetCopyOnWrite(true)
				mask1 := bitset.New(0)
				startM := rand.Intn(65536 * 20)
				endM := startM + 100000
				mask.Flip(uint64(startM), uint64(endM))
				FlipRange(startM, endM, mask1)
				mask.Flip(0, 65536*20+100000)
				FlipRange(0, 65536*20+100000, mask1)
				rb.And(mask)
				bs.InPlaceIntersection(mask1)
			}
			// see if we can detect incorrectly shared containers
			if rand.Float64() < 0.1 {
				irrelevant := Flip(rb, 10, 100000)
				irrelevant.Flip(5, 200000)
				irrelevant.Flip(190000, 260000)
			}
			if float64(i) > checkTime {
				assert.True(t, equalsBitSet(bs, rb))
				checkTime *= 1.5
			}
		}
	})

	t.Run("ortest", func(t *testing.T) {
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		for k := 0; k < 4000; k++ {
			rr.AddInt(k)
		}
		rr.AddInt(100000)
		rr.AddInt(110000)
		rr2 := NewBitmap()
		rr2.SetCopyOnWrite(true)
		for k := 0; k < 4000; k++ {
			rr2.AddInt(k)
		}

		rror := Or(rr, rr2)

		array := rror.ToArray()

		rr.Or(rr2)
		arrayirr := rr.ToArray()

		assert.True(t, IntsEquals(array, arrayirr))
	})

	t.Run("ORtest", func(t *testing.T) {
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		for k := 4000; k < 4256; k++ {
			rr.AddInt(k)
		}
		for k := 65536; k < 65536+4000; k++ {
			rr.AddInt(k)
		}
		for k := 3 * 65536; k < 3*65536+9000; k++ {
			rr.AddInt(k)
		}
		for k := 4 * 65535; k < 4*65535+7000; k++ {
			rr.AddInt(k)
		}
		for k := 6 * 65535; k < 6*65535+10000; k++ {
			rr.AddInt(k)
		}
		for k := 8 * 65535; k < 8*65535+1000; k++ {
			rr.AddInt(k)
		}
		for k := 9 * 65535; k < 9*65535+30000; k++ {
			rr.AddInt(k)
		}

		rr2 := NewBitmap()
		rr2.SetCopyOnWrite(true)
		for k := 4000; k < 4256; k++ {
			rr2.AddInt(k)
		}
		for k := 65536; k < 65536+4000; k++ {
			rr2.AddInt(k)
		}
		for k := 3*65536 + 2000; k < 3*65536+6000; k++ {
			rr2.AddInt(k)
		}
		for k := 6 * 65535; k < 6*65535+1000; k++ {
			rr2.AddInt(k)
		}
		for k := 7 * 65535; k < 7*65535+1000; k++ {
			rr2.AddInt(k)
		}
		for k := 10 * 65535; k < 10*65535+5000; k++ {
			rr2.AddInt(k)
		}

		correct := Or(rr, rr2)
		rr.Or(rr2)

		assert.True(t, correct.Equals(rr))
	})

	t.Run("ortest2", func(t *testing.T) {
		arrayrr := make([]uint32, 4000+4000+2)
		pos := 0
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		for k := 0; k < 4000; k++ {
			rr.AddInt(k)
			arrayrr[pos] = uint32(k)
			pos++
		}
		rr.AddInt(100000)
		rr.AddInt(110000)
		rr2 := NewBitmap()
		rr2.SetCopyOnWrite(true)
		for k := 4000; k < 8000; k++ {
			rr2.AddInt(k)
			arrayrr[pos] = uint32(k)
			pos++
		}

		arrayrr[pos] = 100000
		pos++
		arrayrr[pos] = 110000
		pos++

		rror := Or(rr, rr2)
		arrayor := rror.ToArray()

		assert.True(t, IntsEquals(arrayor, arrayrr))
	})

	t.Run("ortest3", func(t *testing.T) {
		V1 := make(map[int]bool)
		V2 := make(map[int]bool)

		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		rr2 := NewBitmap()
		rr2.SetCopyOnWrite(true)
		for k := 0; k < 4000; k++ {
			rr2.AddInt(k)
			V1[k] = true
		}
		for k := 3500; k < 4500; k++ {
			rr.AddInt(k)
			V1[k] = true
		}
		for k := 4000; k < 65000; k++ {
			rr2.AddInt(k)
			V1[k] = true
		}

		// In the second node of each roaring bitmap, we have two bitmap
		// containers.
		// So, we will check the union between two BitmapContainers
		for k := 65536; k < 65536+10000; k++ {
			rr.AddInt(k)
			V1[k] = true
		}

		for k := 65536; k < 65536+14000; k++ {
			rr2.AddInt(k)
			V1[k] = true
		}

		// In the 3rd node of each Roaring Bitmap, we have an
		// ArrayContainer, so, we will try the union between two
		// ArrayContainers.
		for k := 4 * 65535; k < 4*65535+1000; k++ {
			rr.AddInt(k)
			V1[k] = true
		}

		for k := 4 * 65535; k < 4*65535+800; k++ {
			rr2.AddInt(k)
			V1[k] = true
		}

		// For the rest, we will check if the union will take them in
		// the result
		for k := 6 * 65535; k < 6*65535+1000; k++ {
			rr.AddInt(k)
			V1[k] = true
		}

		for k := 7 * 65535; k < 7*65535+2000; k++ {
			rr2.AddInt(k)
			V1[k] = true
		}

		rror := Or(rr, rr2)
		valide := true

		for _, k := range rror.ToArray() {
			_, found := V1[int(k)]
			if !found {
				valide = false
			}
			V2[int(k)] = true
		}

		for k := range V1 {
			_, found := V2[k]
			if !found {
				valide = false
			}
		}

		assert.True(t, valide)
	})

	t.Run("ortest4", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb2 := NewBitmap()
		rb2.SetCopyOnWrite(true)

		for i := 0; i < 200000; i += 4 {
			rb2.AddInt(i)
		}
		for i := 200000; i < 400000; i += 14 {
			rb2.AddInt(i)
		}
		rb2card := rb2.GetCardinality()

		// check or against an empty bitmap
		orresult := Or(rb, rb2)
		off := Or(rb2, rb)

		assert.True(t, orresult.Equals(off))
		assert.Equal(t, orresult.GetCardinality(), rb2card)

		for i := 500000; i < 600000; i += 14 {
			rb.AddInt(i)
		}
		for i := 200000; i < 400000; i += 3 {
			rb2.AddInt(i)
		}
		// check or against an empty bitmap
		orresult2 := Or(rb, rb2)

		assert.Equal(t, orresult.GetCardinality(), rb2card)
		assert.Equal(t, rb2.GetCardinality()+rb.GetCardinality(), orresult2.GetCardinality())

		rb.Or(rb2)
		assert.True(t, rb.Equals(orresult2))
	})

	t.Run("randomTest", func(t *testing.T) {
		rTestCOW(t, 15)
		rTestCOW(t, 1024)
		rTestCOW(t, 4096)
		rTestCOW(t, 65536)
		rTestCOW(t, 65536*16)
	})

	t.Run("SimpleCardinality", func(t *testing.T) {
		N := 512
		gap := 70

		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		for k := 0; k < N; k++ {
			rb.AddInt(k * gap)
			assert.EqualValues(t, k+1, rb.GetCardinality())
		}

		assert.EqualValues(t, N, rb.GetCardinality())

		for k := 0; k < N; k++ {
			rb.AddInt(k * gap)
			assert.EqualValues(t, N, rb.GetCardinality())
		}
	})

	t.Run("XORtest", func(t *testing.T) {
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		for k := 4000; k < 4256; k++ {
			rr.AddInt(k)
		}
		for k := 65536; k < 65536+4000; k++ {
			rr.AddInt(k)
		}
		for k := 3 * 65536; k < 3*65536+9000; k++ {
			rr.AddInt(k)
		}
		for k := 4 * 65535; k < 4*65535+7000; k++ {
			rr.AddInt(k)
		}
		for k := 6 * 65535; k < 6*65535+10000; k++ {
			rr.AddInt(k)
		}
		for k := 8 * 65535; k < 8*65535+1000; k++ {
			rr.AddInt(k)
		}
		for k := 9 * 65535; k < 9*65535+30000; k++ {
			rr.AddInt(k)
		}

		rr2 := NewBitmap()
		rr2.SetCopyOnWrite(true)
		for k := 4000; k < 4256; k++ {
			rr2.AddInt(k)
		}
		for k := 65536; k < 65536+4000; k++ {
			rr2.AddInt(k)
		}
		for k := 3*65536 + 2000; k < 3*65536+6000; k++ {
			rr2.AddInt(k)
		}
		for k := 6 * 65535; k < 6*65535+1000; k++ {
			rr2.AddInt(k)
		}
		for k := 7 * 65535; k < 7*65535+1000; k++ {
			rr2.AddInt(k)
		}
		for k := 10 * 65535; k < 10*65535+5000; k++ {
			rr2.AddInt(k)
		}
		correct := Xor(rr, rr2)
		rr.Xor(rr2)

		assert.True(t, correct.Equals(rr))
	})

	t.Run("xortest1", func(t *testing.T) {
		V1 := make(map[int]bool)
		V2 := make(map[int]bool)

		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		rr2 := NewBitmap()
		rr2.SetCopyOnWrite(true)
		// For the first 65536: rr2 has a bitmap container, and rr has
		// an array container.
		// We will check the union between a BitmapCintainer and an
		// arrayContainer
		for k := 0; k < 4000; k++ {
			rr2.AddInt(k)
			if k < 3500 {
				V1[k] = true
			}
		}
		for k := 3500; k < 4500; k++ {
			rr.AddInt(k)
		}
		for k := 4000; k < 65000; k++ {
			rr2.AddInt(k)
			if k >= 4500 {
				V1[k] = true
			}
		}

		for k := 65536; k < 65536+30000; k++ {
			rr.AddInt(k)
		}

		for k := 65536; k < 65536+50000; k++ {
			rr2.AddInt(k)
			if k >= 65536+30000 {
				V1[k] = true
			}
		}

		// In the 3rd node of each Roaring Bitmap, we have an
		// ArrayContainer. So, we will try the union between two
		// ArrayContainers.
		for k := 4 * 65535; k < 4*65535+1000; k++ {
			rr.AddInt(k)
			if k >= (4*65535 + 800) {
				V1[k] = true
			}
		}

		for k := 4 * 65535; k < 4*65535+800; k++ {
			rr2.AddInt(k)
		}

		for k := 6 * 65535; k < 6*65535+1000; k++ {
			rr.AddInt(k)
			V1[k] = true
		}

		for k := 7 * 65535; k < 7*65535+2000; k++ {
			rr2.AddInt(k)
			V1[k] = true
		}

		rrxor := Xor(rr, rr2)
		valide := true

		for _, i := range rrxor.ToArray() {
			_, found := V1[int(i)]
			if !found {
				valide = false
			}
			V2[int(i)] = true
		}
		for k := range V1 {
			_, found := V2[k]
			if !found {
				valide = false
			}
		}

		assert.True(t, valide)
	})
}

func TestXORtest4COW(t *testing.T) {
	rb := NewBitmap()
	rb.SetCopyOnWrite(true)
	rb2 := NewBitmap()
	rb2.SetCopyOnWrite(true)
	counter := 0

	for i := 0; i < 200000; i += 4 {
		rb2.AddInt(i)
		counter++
	}

	assert.EqualValues(t, counter, rb2.GetCardinality())

	for i := 200000; i < 400000; i += 14 {
		rb2.AddInt(i)
		counter++
	}

	assert.EqualValues(t, counter, rb2.GetCardinality())

	rb2card := rb2.GetCardinality()
	assert.EqualValues(t, counter, rb2card)

	// check or against an empty bitmap
	xorresult := Xor(rb, rb2)
	assert.EqualValues(t, counter, xorresult.GetCardinality())

	off := Or(rb2, rb)

	assert.EqualValues(t, counter, off.GetCardinality())
	assert.True(t, xorresult.Equals(off))

	assert.Equal(t, xorresult.GetCardinality(), rb2card)
	for i := 500000; i < 600000; i += 14 {
		rb.AddInt(i)
	}
	for i := 200000; i < 400000; i += 3 {
		rb2.AddInt(i)
	}
	// check or against an empty bitmap
	xorresult2 := Xor(rb, rb2)

	assert.Equal(t, xorresult.GetCardinality(), rb2card)
	assert.Equal(t, xorresult2.GetCardinality(), rb2.GetCardinality()+rb.GetCardinality())

	rb.Xor(rb2)
	assert.True(t, xorresult2.Equals(rb))
	//need to add the massives
}

func TestBigRandomCOW(t *testing.T) {
	t.Run("randomTest", func(t *testing.T) {
		rTestCOW(t, 15)
		rTestCOW(t, 100)
		rTestCOW(t, 512)
		rTestCOW(t, 1023)
		rTestCOW(t, 1025)
		rTestCOW(t, 4095)
		rTestCOW(t, 4096)
		rTestCOW(t, 4097)
		rTestCOW(t, 65536)
		rTestCOW(t, 65536*16)
	})
}

func rTestCOW(t *testing.T, N int) {
	log.Println("rtest N=", N)
	for gap := 1; gap <= 65536; gap *= 2 {
		bs1 := bitset.New(0)
		rb1 := NewBitmap()
		rb1.SetCopyOnWrite(true)
		for x := 0; x <= N; x += gap {
			bs1.Set(uint(x))
			rb1.AddInt(x)
		}

		assert.EqualValues(t, rb1.GetCardinality(), bs1.Count())
		assert.True(t, equalsBitSet(bs1, rb1))

		for offset := 1; offset <= gap; offset *= 2 {
			bs2 := bitset.New(0)
			rb2 := NewBitmap()
			rb2.SetCopyOnWrite(true)
			for x := 0; x <= N; x += gap {
				bs2.Set(uint(x + offset))
				rb2.AddInt(x + offset)
			}

			assert.EqualValues(t, rb2.GetCardinality(), bs2.Count())
			assert.True(t, equalsBitSet(bs2, rb2))

			clonebs1 := bs1.Clone()
			clonebs1.InPlaceIntersection(bs2)
			if !equalsBitSet(clonebs1, And(rb1, rb2)) {
				v := rb1.Clone()
				v.And(rb2)
				assert.True(t, equalsBitSet(clonebs1, v))
			}

			// testing OR
			clonebs1 = bs1.Clone()
			clonebs1.InPlaceUnion(bs2)

			assert.True(t, equalsBitSet(clonebs1, Or(rb1, rb2)))

			// testing XOR
			clonebs1 = bs1.Clone()
			clonebs1.InPlaceSymmetricDifference(bs2)

			assert.True(t, equalsBitSet(clonebs1, Xor(rb1, rb2)))

			//testing NOTAND
			clonebs1 = bs1.Clone()
			clonebs1.InPlaceDifference(bs2)

			assert.True(t, equalsBitSet(clonebs1, AndNot(rb1, rb2)))
		}
	}
}

func TestRoaringArrayCOW(t *testing.T) {
	a := newRoaringArray()

	t.Run("Test Init", func(t *testing.T) {
		assert.Equal(t, 0, a.size())
	})

	t.Run("Test Insert", func(t *testing.T) {
		a.appendContainer(0, newArrayContainer(), false)

		assert.Equal(t, 1, a.size())
	})

	t.Run("Test Remove", func(t *testing.T) {
		a.remove(0)
		assert.Equal(t, 0, a.size())
	})

	t.Run("Test popcount Full", func(t *testing.T) {
		res := popcount(uint64(0xffffffffffffffff))
		assert.EqualValues(t, 64, res)
	})

	t.Run("Test popcount Empty", func(t *testing.T) {
		res := popcount(0)
		assert.EqualValues(t, 0, res)
	})

	t.Run("Test popcount 16", func(t *testing.T) {
		res := popcount(0xff00ff)
		assert.EqualValues(t, 16, res)
	})

	t.Run("Test ArrayContainer Add", func(t *testing.T) {
		ar := newArrayContainer()
		ar.iadd(1)

		assert.EqualValues(t, 1, ar.getCardinality())
	})

	t.Run("Test ArrayContainer Add wacky", func(t *testing.T) {
		ar := newArrayContainer()
		ar.iadd(0)
		ar.iadd(5000)

		assert.EqualValues(t, 2, ar.getCardinality())
	})

	t.Run("Test ArrayContainer Add Reverse", func(t *testing.T) {
		ar := newArrayContainer()
		ar.iadd(5000)
		ar.iadd(2048)
		ar.iadd(0)

		assert.EqualValues(t, 3, ar.getCardinality())
	})

	t.Run("Test BitmapContainer Add ", func(t *testing.T) {
		bm := newBitmapContainer()
		bm.iadd(0)

		assert.EqualValues(t, 1, bm.getCardinality())
	})
}

func TestFlipBigACOW(t *testing.T) {
	numCases := 1000
	bs := bitset.New(0)
	checkTime := 2.0
	rb1 := NewBitmap()
	rb1.SetCopyOnWrite(true)
	rb2 := NewBitmap()
	rb2.SetCopyOnWrite(true)

	for i := 0; i < numCases; i++ {
		start := rand.Intn(65536 * 20)
		end := rand.Intn(65536 * 20)
		if rand.Float64() < 0.1 {
			end = start + rand.Intn(100)
		}

		if (i & 1) == 0 {
			rb2 = FlipInt(rb1, start, end)
			// tweak the other, catch bad sharing
			rb1.FlipInt(rand.Intn(65536*20), rand.Intn(65536*20))
		} else {
			rb1 = FlipInt(rb2, start, end)
			rb2.FlipInt(rand.Intn(65536*20), rand.Intn(65536*20))
		}

		if start < end {
			FlipRange(start, end, bs) // throws exception
		}
		// otherwise
		// insert some more ANDs to keep things sparser
		if (rand.Float64() < 0.2) && (i&1) == 0 {
			mask := NewBitmap()
			mask.SetCopyOnWrite(true)
			mask1 := bitset.New(0)
			startM := rand.Intn(65536 * 20)
			endM := startM + 100000
			mask.FlipInt(startM, endM)
			FlipRange(startM, endM, mask1)
			mask.FlipInt(0, 65536*20+100000)
			FlipRange(0, 65536*20+100000, mask1)
			rb2.And(mask)
			bs.InPlaceIntersection(mask1)
		}

		if float64(i) > checkTime {
			var rb *Bitmap

			if (i & 1) == 0 {
				rb = rb2
			} else {
				rb = rb1
			}
			assert.True(t, equalsBitSet(bs, rb))
			checkTime *= 1.5
		}
	}
}

func TestDoubleAddCOW(t *testing.T) {
	t.Run("doubleadd ", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb.AddRange(65533, 65536)
		rb.AddRange(65530, 65536)
		rb2 := NewBitmap()
		rb2.SetCopyOnWrite(true)
		rb2.AddRange(65530, 65536)

		assert.True(t, rb.Equals(rb2))

		rb2.RemoveRange(65530, 65536)
		assert.EqualValues(t, 0, rb2.GetCardinality())
	})

	t.Run("doubleadd2 ", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb.AddRange(65533, 65536*20)
		rb.AddRange(65530, 65536*20)
		rb2 := NewBitmap()
		rb2.SetCopyOnWrite(true)
		rb2.AddRange(65530, 65536*20)

		assert.True(t, rb.Equals(rb2))

		rb2.RemoveRange(65530, 65536*20)
		assert.EqualValues(t, 0, rb2.GetCardinality())
	})

	t.Run("doubleadd3 ", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb.AddRange(65533, 65536*20+10)
		rb.AddRange(65530, 65536*20+10)

		rb2 := NewBitmap()
		rb2.SetCopyOnWrite(true)
		rb2.AddRange(65530, 65536*20+10)
		assert.True(t, rb.Equals(rb2))
		rb2.RemoveRange(65530, 65536*20+1)

		assert.EqualValues(t, 9, rb2.GetCardinality())
	})

	t.Run("doubleadd4 ", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb.AddRange(65533, 65536*20)
		rb.RemoveRange(65533+5, 65536*20)

		assert.EqualValues(t, 5, rb.GetCardinality())
	})

	t.Run("doubleadd5 ", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb.AddRange(65533, 65536*20)
		rb.RemoveRange(65533+5, 65536*20-5)

		assert.EqualValues(t, 10, rb.GetCardinality())
	})

	t.Run("doubleadd6 ", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb.AddRange(65533, 65536*20-5)
		rb.RemoveRange(65533+5, 65536*20-10)

		assert.EqualValues(t, 10, rb.GetCardinality())
	})

	t.Run("doubleadd7 ", func(t *testing.T) {
		rb := NewBitmap()
		rb.SetCopyOnWrite(true)
		rb.AddRange(65533, 65536*20+1)
		rb.RemoveRange(65533+1, 65536*20)

		assert.EqualValues(t, 2, rb.GetCardinality())
	})

	t.Run("AndNotBug01 ", func(t *testing.T) {
		rb1 := NewBitmap()
		rb1.SetCopyOnWrite(true)
		rb1.AddRange(0, 60000)
		rb2 := NewBitmap()
		rb2.SetCopyOnWrite(true)
		rb2.AddRange(60000-10, 60000+10)
		rb2.AndNot(rb1)
		rb3 := NewBitmap()
		rb3.SetCopyOnWrite(true)
		rb3.AddRange(60000, 60000+10)

		assert.True(t, rb2.Equals(rb3))
	})
}

func TestAndNotCOW(t *testing.T) {
	rr := NewBitmap()
	rr.SetCopyOnWrite(true)
	for k := 4000; k < 4256; k++ {
		rr.AddInt(k)
	}
	for k := 65536; k < 65536+4000; k++ {
		rr.AddInt(k)
	}
	for k := 3 * 65536; k < 3*65536+9000; k++ {
		rr.AddInt(k)
	}
	for k := 4 * 65535; k < 4*65535+7000; k++ {
		rr.AddInt(k)
	}
	for k := 6 * 65535; k < 6*65535+10000; k++ {
		rr.AddInt(k)
	}
	for k := 8 * 65535; k < 8*65535+1000; k++ {
		rr.AddInt(k)
	}
	for k := 9 * 65535; k < 9*65535+30000; k++ {
		rr.AddInt(k)
	}

	rr2 := NewBitmap()
	rr2.SetCopyOnWrite(true)
	for k := 4000; k < 4256; k++ {
		rr2.AddInt(k)
	}
	for k := 65536; k < 65536+4000; k++ {
		rr2.AddInt(k)
	}
	for k := 3*65536 + 2000; k < 3*65536+6000; k++ {
		rr2.AddInt(k)
	}
	for k := 6 * 65535; k < 6*65535+1000; k++ {
		rr2.AddInt(k)
	}
	for k := 7 * 65535; k < 7*65535+1000; k++ {
		rr2.AddInt(k)
	}
	for k := 10 * 65535; k < 10*65535+5000; k++ {
		rr2.AddInt(k)
	}
	correct := AndNot(rr, rr2)
	rr.AndNot(rr2)

	assert.True(t, correct.Equals(rr))
}

func TestStatsCOW(t *testing.T) {
	t.Run("Test Stats with empty bitmap", func(t *testing.T) {
		expectedStats := Statistics{}
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)

		assert.EqualValues(t, expectedStats, rr.Stats())
	})

	t.Run("Test Stats with bitmap Container", func(t *testing.T) {
		// Given a bitmap that should have a single bitmap container
		expectedStats := Statistics{
			Cardinality: 60000,
			Containers:  1,

			BitmapContainers:      1,
			BitmapContainerValues: 60000,
			BitmapContainerBytes:  8192,

			RunContainers:      0,
			RunContainerBytes:  0,
			RunContainerValues: 0,
		}
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		for i := uint32(0); i < 60000; i++ {
			rr.Add(i)
		}

		assert.EqualValues(t, expectedStats, rr.Stats())
	})

	t.Run("Test Stats with run Container", func(t *testing.T) {
		// Given that we should have a single run container
		intSize := int(unsafe.Sizeof(int(0)))
		var runContainerBytes uint64
		if intSize == 4 {
			runContainerBytes = 40
		} else {
			runContainerBytes = 52
		}

		expectedStats := Statistics{
			Cardinality: 60000,
			Containers:  1,

			BitmapContainers:      0,
			BitmapContainerValues: 0,
			BitmapContainerBytes:  0,

			RunContainers:      1,
			RunContainerBytes:  runContainerBytes,
			RunContainerValues: 60000,
		}
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		rr.AddRange(0, 60000)

		assert.EqualValues(t, expectedStats, rr.Stats())
	})

	t.Run("Test Stats with Array Container", func(t *testing.T) {
		// Given a bitmap that should have a single array container
		expectedStats := Statistics{
			Cardinality: 2,
			Containers:  1,

			ArrayContainers:      1,
			ArrayContainerValues: 2,
			ArrayContainerBytes:  4,
		}
		rr := NewBitmap()
		rr.SetCopyOnWrite(true)
		rr.Add(2)
		rr.Add(4)

		assert.EqualValues(t, expectedStats, rr.Stats())
	})
}

func TestFlipVerySmallCOW(t *testing.T) {
	rb := NewBitmap()
	rb.SetCopyOnWrite(true)
	rb.Flip(0, 10) // got [0,9], card is 10
	rb.Flip(0, 1)  // give back the number 0, card goes to 9
	rbcard := rb.GetCardinality()

	assert.EqualValues(t, 9, rbcard)
}

func TestCloneCOWContainers(t *testing.T) {
	rb := NewBitmap()
	rb.AddRange(0, 3000)
	buf := &bytes.Buffer{}
	rb.WriteTo(buf)

	newRb1 := NewBitmap()
	newRb1.FromBuffer(buf.Bytes())
	newRb1.CloneCopyOnWriteContainers()

	rb2 := NewBitmap()
	rb2.AddRange(3000, 6000)
	buf.Reset()
	rb2.WriteTo(buf)

	assert.EqualValues(t, rb.ToArray(), newRb1.ToArray())
}

func TestInPlaceCOWContainers(t *testing.T) {
	// write bitmap
	wb1 := NewBitmap()
	wb2 := NewBitmap()

	wb1.AddRange(0, 3000)
	wb2.AddRange(2000, 5000)

	buf1 := &bytes.Buffer{}
	buf2 := &bytes.Buffer{}

	wb1.WriteTo(buf1)
	wb2.WriteTo(buf2)

	// read bitmaps
	rb1 := NewBitmap()
	rb2 := NewBitmap()

	rb1.FromBuffer(buf1.Bytes())
	rb2.FromBuffer(buf2.Bytes())

	assert.True(t, wb1.Equals(rb1))
	assert.True(t, wb2.Equals(rb2))

	rb1.Or(rb2)

	assert.True(t, Or(wb1, wb2).Equals(rb1))
	assert.True(t, wb2.Equals(rb2))

	rb3 := NewBitmap()
	rb3.FromBuffer(buf1.Bytes())

	assert.True(t, rb3.Equals(wb1))
}