make AutoLayout skip over coordinates if there is a mapping at that exact position

frontend/src/Metamaps/AutoLayout.js

@@ -1,3 +1,5 @@
+import Active from './Active'
+
 const AutoLayout = {
   nextX: 0,
   nextY: 0,
@@ -7,7 +9,7 @@ const AutoLayout = {
   nextYshift: 0,
   timeToTurn: 0,
 
-  getNextCoord: function () {
+  getNextCoord: function (opts = {}) {
     var self = AutoLayout
     var nextX = self.nextX
     var nextY = self.nextY
@@ -49,9 +51,22 @@ const AutoLayout = {
       }
     }
 
-    return {
-      x: nextX,
-      y: nextY
+    if (opts.map && self.coordsTaken(nextX, nextY, opts.map)) {
+      // check if the coordinate is already taken on the current map
+      return self.getNextCoord(opts)
+    } else {
+      return {
+        x: nextX,
+        y: nextY
+      }
+    }
+  },
+  coordsTaken: function(x, y, map) {
+    const mappings = map.getMappings()
+    if (mappings.findWhere({ xloc: x, yloc: y })) {
+      return true
+    } else {
+      return false
     }
   },
   resetSpiral: function () {

frontend/src/Metamaps/Import.js

@@ -227,7 +227,7 @@ const Import = {
     parsedTopics.forEach(function (topic) {
       let coords = { x: topic.x, y: topic.y }
       if (!coords.x || !coords.y) {
-        coords = AutoLayout.getNextCoord()
+        coords = AutoLayout.getNextCoord({ map: Active.Map })
       }
 
       if (!topic.name && topic.link ||
@@ -349,7 +349,7 @@ const Import = {
   handleURL: function (url, opts = {}) {
     let coords = opts.coords
     if (!coords || coords.x === undefined || coords.y === undefined) {
-      coords = AutoLayout.getNextCoord()
+      coords = AutoLayout.getNextCoord({ map: Active.Map })
     }
 
     const name = opts.name || 'Link'