graflow: added autoplace align 1st & last

bzGraflow.js

@@ -396,7 +396,8 @@ class BZgraflow extends Buildoz{
         return(path)
     }
 
-    autoPlace(orientation = 'horizontal', gapx = 80, gapy = 80, tween=1000){
+    autoPlace(orientation = 'horizontal', gapx = 80, gapy = 80, tween=1000, align='center'){
+        console.log('autoPlace', orientation, gapx, gapy, tween, align)
         // Loops create infinite recursion in dfs for getting parents & adjacency lists: Remove them !
         let linksWithoutBackEdges
         if(this.hasAnyLoop(this.flow.nodes, this.flow.links)){
@@ -462,7 +463,22 @@ class BZgraflow extends Buildoz{
             let x = gapx
             for(const [idx, layer] of layers.entries()){
                 let wMax = this.getMaxWidth(layer)
-                let y = ((maxHeight - layerHeights[idx]) / 2) + gapy
+                let y = 0
+                switch(align){
+                    case'center':
+                        y = ((maxHeight - layerHeights[idx]) / 2) + gapy
+                        break
+                    case'first':
+                        y = gapy
+                        break
+                    case'last':
+                        y = maxHeight - layerHeights[idx] + gapy
+                        break
+                    case 'auto':
+                        //TODO
+                        y = ((maxHeight - layerHeights[idx]) / 2) + gapy
+                        break
+                }
                 for(const nid of layer){
                     if(!nid.startsWith('longLinkPlaceHolder_')) {
                         const bb = this.stagedNodes[nid].getBoundingClientRect()