fix(tooltip): fixes md-direction attribute functionality

Closes #1673

src/components/tooltip/tooltip.js

@@ -149,25 +149,14 @@ function MdTooltipDirective($timeout, $window, $$rAF, $document, $mdUtil, $mdThe
  function positionTooltip() {
  var tipRect = $mdUtil.offsetRect(element, tooltipParent);
  var parentRect = $mdUtil.offsetRect(parent, tooltipParent);
-
- // Default to bottom position if possible
- var tipDirection = 'bottom';
- var newPosition = {
- left: parentRect.left + parentRect.width / 2 - tipRect.width / 2,
- top: parentRect.top + parentRect.height
- };
-
- // If element bleeds over left/right of the window, place it on the edge of the window.
- newPosition.left = Math.min(
- newPosition.left,
- tooltipParent.prop('scrollWidth') - tipRect.width - TOOLTIP_WINDOW_EDGE_SPACE
- );
- newPosition.left = Math.max(newPosition.left, TOOLTIP_WINDOW_EDGE_SPACE);
-
- // If element bleeds over the bottom of the window, place it above the parent.
- if (newPosition.top + tipRect.height > tooltipParent.prop('scrollHeight')) {
- newPosition.top = parentRect.top - tipRect.height;
- tipDirection = 'top';
+ var newPosition = getPosition(direction);
+
+ // If the user provided a direction, just nudge the tooltip onto the screen
+ // Otherwise, recalculate based on 'top' since default is 'bottom'
+ if (direction) {
+ newPosition = fitInParent(newPosition);
+ } else if (newPosition.top > tooltipParent.prop('scrollHeight') - tipRect.height - TOOLTIP_WINDOW_EDGE_SPACE) {
+ newPosition = fitInParent(getPosition('top'));
  }
 
  element.css({top: newPosition.top + 'px', left: newPosition.left + 'px'});
@@ -190,12 +179,12 @@ function MdTooltipDirective($timeout, $window, $$rAF, $document, $mdUtil, $mdThe
  });
  }
 
- function fitOnScreen (pos) {
- var newPosition = {};
- newPosition.left = Math.min( pos.left, tooltipParent.prop('scrollWidth') - tipRect.width - TOOLTIP_WINDOW_EDGE_SPACE );
- newPosition.left = Math.max( pos.left, TOOLTIP_WINDOW_EDGE_SPACE );
- newPosition.top = Math.min( pos.top, tooltipParent.prop('scrollHeight') - tipRect.height - TOOLTIP_WINDOW_EDGE_SPACE );
- newPosition.top = Math.max( pos.top, TOOLTIP_WINDOW_EDGE_SPACE );
+ function fitInParent (pos) {
+ var newPosition = { left: pos.left, top: pos.top };
+ newPosition.left = Math.min( newPosition.left, tooltipParent.prop('scrollWidth') - tipRect.width - TOOLTIP_WINDOW_EDGE_SPACE );
+ newPosition.left = Math.max( newPosition.left, TOOLTIP_WINDOW_EDGE_SPACE );
+ newPosition.top = Math.min( newPosition.top, tooltipParent.prop('scrollHeight') - tipRect.height - TOOLTIP_WINDOW_EDGE_SPACE );
+ newPosition.top = Math.max( newPosition.top, TOOLTIP_WINDOW_EDGE_SPACE );
  return newPosition;
  }