From 0c3f61a42675f704ee3b9c6fd29660941dbcd70e Mon Sep 17 00:00:00 2001
From: Matt Jaffee <jaffee@umbel.com>
Date: Thu, 18 May 2017 17:22:13 -0500
Subject: [PATCH] implement intersectArrayRun

---
 roaring/roaring.go               | 42 ++++++++++++++++++++++++++++++++
 roaring/roaring_internal_test.go | 40 ++++++++++++++++++++++++++++++
 2 files changed, 82 insertions(+)

diff --git a/roaring/roaring.go b/roaring/roaring.go
index 09d173ede..1d8ef1223 100644
--- a/roaring/roaring.go
+++ b/roaring/roaring.go
@@ -1603,12 +1603,24 @@ func intersect(a, b *container) *container {
 	if a.isArray() {
 		if b.isArray() {
 			return intersectArrayArray(a, b)
+		} else if b.isRun() {
+			return intersectArrayRun(a, b)
 		} else {
 			return intersectArrayBitmap(a, b)
 		}
+	} else if a.isRun() {
+		if b.isArray() {
+			return intersectArrayRun(b, a)
+		} else if b.isRun() {
+			return intersectRunRun(a, b)
+		} else {
+			return intersectBitmapRun(b, a)
+		}
 	} else {
 		if b.isArray() {
 			return intersectArrayBitmap(b, a)
+		} else if b.isRun() {
+			return intersectBitmapRun(a, b)
 		} else {
 			return intersectBitmapBitmap(a, b)
 		}
@@ -1633,6 +1645,36 @@ func intersectArrayArray(a, b *container) *container {
 	return output
 }
 
+func intersectArrayRun(a, b *container) *container {
+	output := &container{}
+	na, nb := len(a.array), len(b.runs)
+	for i, j := 0, 0; i < na && j < nb; {
+		va, vb := a.array[i], b.runs[j]
+		if va < vb.start {
+			i++
+		} else if va > vb.last {
+			j++
+		} else {
+			output.array = append(output.array, va)
+			output.n++
+			i++
+		}
+	}
+	return output
+}
+
+func intersectRunRun(a, b *container) *container {
+	output := &container{}
+	// TODO
+	return output
+}
+
+func intersectBitmapRun(a, b *container) *container {
+	output := &container{}
+	// TODO
+	return output
+}
+
 func intersectArrayBitmap(a, b *container) *container {
 	output := &container{}
 	itr := newBufIterator(newBitmapIterator(b.bitmap))
diff --git a/roaring/roaring_internal_test.go b/roaring/roaring_internal_test.go
index ec022305c..8f771a1fe 100644
--- a/roaring/roaring_internal_test.go
+++ b/roaring/roaring_internal_test.go
@@ -350,3 +350,43 @@ func TestIntersectionCountRunRun(t *testing.T) {
 		}
 	}
 }
+
+func TestIntersectArrayRun(t *testing.T) {
+	a := &container{}
+	b := &container{}
+	tests := []struct {
+		array []uint32
+		runs  []interval32
+		exp   []uint32
+	}{
+		{
+			array: []uint32{1, 4, 5, 7, 10, 11, 12},
+			runs:  []interval32{{start: 5, last: 10}},
+			exp:   []uint32{5, 7, 10},
+		},
+		{
+			array: []uint32{},
+			runs:  []interval32{{start: 5, last: 10}},
+			exp:   []uint32(nil),
+		},
+		{
+			array: []uint32{1, 4, 5, 7, 10, 11, 12},
+			runs:  []interval32{},
+			exp:   []uint32(nil),
+		},
+		{
+			array: []uint32{0, 1, 4, 5, 7, 10, 11, 12},
+			runs:  []interval32{{start: 0, last: 5}, {start: 7, last: 7}},
+			exp:   []uint32{0, 1, 4, 5, 7},
+		},
+	}
+
+	for i, test := range tests {
+		a.array = test.array
+		b.runs = test.runs
+		ret := intersectArrayRun(a, b)
+		if !reflect.DeepEqual(ret.array, test.exp) {
+			t.Fatalf("test #%v expected %v, but got %v", i, test.exp, ret.array)
+		}
+	}
+}