change code structure

src/components/Splitpanes/splitter.js

@@ -0,0 +1,36 @@
+export default {
+  // Get the cursor position relative to the splitpane container.
+  getCurrentMouseDrag (event, container) {
+    const rect = container.getBoundingClientRect()
+    const { clientX, clientY } = ('ontouchstart' in window && event.touches)
+      ? event.touches[0]
+      : event
+    return {
+      x: clientX - rect.left,
+      y: clientY - rect.top
+    }
+  },
+
+  // Returns the drag percentage of the splitter relative to the 2 panes it's inbetween.
+  getCurrentDragPercentage (event, container, isHorisontal) {
+    let drag = this.getCurrentMouseDrag(event, container)
+    drag = drag[isHorisontal ? 'y' : 'x']
+    const containerSize = container[isHorisontal ? 'clientHeight' : 'clientWidth']
+    return drag * 100 / containerSize
+  },
+
+  // Returns the new position in percents.
+  calculateOffset (event, { container, isHorisontal, paneBeforeMax, paneAfterMax }) {
+    const dragPercentage = this.getCurrentDragPercentage(event, container, isHorisontal)
+
+    const paneBeforeMaxReached = paneBeforeMax < 100 && (dragPercentage >= paneBeforeMax)
+    const paneAfterMaxReached = paneAfterMax < 100 && (dragPercentage <= 100 - paneAfterMax)
+
+    // Prevent dragging beyond pane max.
+    if (paneBeforeMaxReached || paneAfterMaxReached) {
+      return paneBeforeMaxReached ? paneBeforeMax : Math.max(100 - paneAfterMax, 0)
+    } else {
+      return Math.min(Math.max(dragPercentage, 0), paneBeforeMax)
+    }
+  }
+}