From 9ac8f3421668bc9540ecaec96fdc15497afe91e3 Mon Sep 17 00:00:00 2001
From: Gavin Nishizawa <gavin@terrastruct.com>
Date: Mon, 18 Sep 2023 21:18:56 -0700
Subject: [PATCH] fix scenario with only center nears

---
 d2layouts/d2near/layout.go | 34 ++++++++++++++++++----------------
 1 file changed, 18 insertions(+), 16 deletions(-)

diff --git a/d2layouts/d2near/layout.go b/d2layouts/d2near/layout.go
index 12cabf793..190317542 100644
--- a/d2layouts/d2near/layout.go
+++ b/d2layouts/d2near/layout.go
@@ -14,12 +14,22 @@ import (
 
 const pad = 20
 
-var CenterNearConstants = map[string]struct{}{
+type set map[string]struct{}
+
+var HorizontalCenterNears = set{
+	"center-left":  {},
+	"center-right": {},
+}
+var VerticalCenterNears = set{
 	"top-center":    {},
-	"center-left":   {},
-	"center-right":  {},
 	"bottom-center": {},
 }
+var NonCenterNears = set{
+	"top-left":     {},
+	"top-right":    {},
+	"bottom-left":  {},
+	"bottom-right": {},
+}
 
 // Layout finds the shapes which are assigned constant near keywords and places them.
 func Layout(ctx context.Context, g *d2graph.Graph, constantNearGraphs []*d2graph.Graph) error {
@@ -37,11 +47,11 @@ func Layout(ctx context.Context, g *d2graph.Graph, constantNearGraphs []*d2graph
 	// Imagine the graph has two long texts, one at top center and one at top left.
 	// Top left should go left enough to not collide with center.
 	// So place the center ones first, then the later ones will consider them for bounding box
-	for _, processCenters := range []bool{true, false} {
+	for _, currentSet := range []set{VerticalCenterNears, HorizontalCenterNears, NonCenterNears} {
 		for _, tempGraph := range constantNearGraphs {
 			obj := tempGraph.Root.ChildrenArray[0]
-			_, isCenterConstant := CenterNearConstants[d2graph.Key(obj.NearKey)[0]]
-			if processCenters == isCenterConstant {
+			_, in := currentSet[d2graph.Key(obj.NearKey)[0]]
+			if in {
 				prevX, prevY := obj.TopLeft.X, obj.TopLeft.Y
 				obj.TopLeft = geo.NewPoint(place(obj))
 				dx, dy := obj.TopLeft.X-prevX, obj.TopLeft.Y-prevY
@@ -64,8 +74,8 @@ func Layout(ctx context.Context, g *d2graph.Graph, constantNearGraphs []*d2graph
 		}
 		for _, tempGraph := range constantNearGraphs {
 			obj := tempGraph.Root.ChildrenArray[0]
-			_, isCenterConstant := CenterNearConstants[d2graph.Key(obj.NearKey)[0]]
-			if processCenters == isCenterConstant {
+			_, in := currentSet[d2graph.Key(obj.NearKey)[0]]
+			if in {
 				// The z-index for constant nears does not matter, as it will not collide
 				g.Objects = append(g.Objects, tempGraph.Objects...)
 				if obj.Parent.Children == nil {
@@ -92,28 +102,20 @@ func place(obj *d2graph.Object) (float64, float64) {
 	switch nearKeyStr {
 	case "top-left":
 		x, y = tl.X-obj.Width-pad, tl.Y-obj.Height-pad
-		break
 	case "top-center":
 		x, y = tl.X+w/2-obj.Width/2, tl.Y-obj.Height-pad
-		break
 	case "top-right":
 		x, y = br.X+pad, tl.Y-obj.Height-pad
-		break
 	case "center-left":
 		x, y = tl.X-obj.Width-pad, tl.Y+h/2-obj.Height/2
-		break
 	case "center-right":
 		x, y = br.X+pad, tl.Y+h/2-obj.Height/2
-		break
 	case "bottom-left":
 		x, y = tl.X-obj.Width-pad, br.Y+pad
-		break
 	case "bottom-center":
 		x, y = br.X-w/2-obj.Width/2, br.Y+pad
-		break
 	case "bottom-right":
 		x, y = br.X+pad, br.Y+pad
-		break
 	}
 
 	if obj.LabelPosition != nil && !strings.Contains(*obj.LabelPosition, "INSIDE") {