fix(dropdown): Open up or down depending on position

internal_packages/composer/lib/send-action-button.cjsx

@@ -87,7 +87,7 @@ class SendActionButton extends React.Component
   _renderSendDropdown: ->
     actionConfigs = @_orderedActionConfigs()
     <ButtonDropdown
-      className={"btn-send dropdown-btn-emphasis dropdown-btn-text"}
+      className={"btn-send btn-emphasis btn-text"}
       style={order: -100}
       primaryItem={@_sendContent(actionConfigs[0].iconUrl)}
       primaryTitle={actionConfigs[0].title}

src/components/button-dropdown.cjsx

@@ -1,5 +1,6 @@
 RetinaImg = require './retina-img'
 {Utils} = require 'nylas-exports'
+classnames = require 'classnames'
 
 React = require 'react'
 class ButtonDropdown extends React.Component
@@ -16,15 +17,17 @@ class ButtonDropdown extends React.Component
     style: {}
 
   constructor: (@props) ->
-    @state = showing: false
+    @state = open: false
 
   render: =>
-    classnames = "button-dropdown #{@props.className ? ''}"
+    classes = classnames
-    classnames += " open" if @state.showing
+      'button-dropdown': true
-    classnames += " bordered" if @props.bordered isnt false
+      'open open-up': @state.open is 'up'
+      'open open-down': @state.open is 'down'
+      'bordered': @props.bordered isnt false
 
     if @props.primaryClick
-      <div ref="button" onBlur={@_onBlur} tabIndex={999} className={classnames} style={@props.style}>
+      <div ref="button" onBlur={@_onBlur} tabIndex={999} className={"#{classes} #{@props.className ? ''}"} style={@props.style}>
         <div className="primary-item"
              title={@props.primaryTitle ? ""}
              onClick={@props.primaryClick}>
@@ -33,34 +36,42 @@ class ButtonDropdown extends React.Component
         <div className="secondary-picker" onClick={@toggleDropdown}>
           <RetinaImg name={"icon-thread-disclosure.png"} mode={RetinaImg.Mode.ContentIsMask}/>
         </div>
-        <div className="secondary-items" onMouseDown={@_onMenuClick}>
+        <div ref="secondaryItems" className="secondary-items" onMouseDown={@_onMenuClick}>
           {@props.menu}
         </div>
       </div>
     else
-      <div ref="button" onBlur={@_onBlur} tabIndex={999} className={classnames} style={@props.style}>
+      <div ref="button" onBlur={@_onBlur} tabIndex={999} className={"#{classes} #{@props.className ? ''}"} style={@props.style}>
         <div className="only-item"
              title={@props.primaryTitle ? ""}
              onClick={@toggleDropdown}>
           {@props.primaryItem}
           <RetinaImg name={"icon-thread-disclosure.png"} style={marginLeft:12} mode={RetinaImg.Mode.ContentIsMask}/>
         </div>
-        <div className="secondary-items left" onMouseDown={@_onMenuClick}>
+        <div ref="secondaryItems" className="secondary-items left" onMouseDown={@_onMenuClick}>
           {@props.menu}
         </div>
       </div>
 
   toggleDropdown: =>
-    @setState(showing: !@state.showing)
+    if @state.open isnt false
+      @setState(open: false)
+    else
+      buttonBottom = React.findDOMNode(@).getBoundingClientRect().bottom
+      openHeight = React.findDOMNode(@refs.secondaryItems).getBoundingClientRect().height
+      if buttonBottom + openHeight > window.innerHeight
+        @setState(open: 'up')
+      else
+        @setState(open: 'down')
 
   _onMenuClick: (event) =>
     if @props.closeOnMenuClick
-      @setState showing: false
+      @setState open: false
 
   _onBlur: (event) =>
     target = event.nativeEvent.relatedTarget
     if target? and React.findDOMNode(@refs.button).contains(target)
       return
-    @setState(showing: false)
+    @setState(open: false)
 
 module.exports = ButtonDropdown

static/components/button-dropdown.less

@@ -5,14 +5,33 @@
   display: inline-block;
 
   &.open {
+    .secondary-items {
+      visibility: inherit;
+    }
+  }
+
+  &.open.open-up {
+    .secondary-items {
+      border-radius: 4px 4px 0 4px;
+      box-shadow: 0 -1px 10px rgba(0, 0, 0, 0.20);
+      top: -100%;
+      transform:translate(0, -2px);
+    }
+    .secondary-picker {
+      border-top-right-radius: 0;
+    }
+  }
+  &.open.open-down {
+    .secondary-items {
+      border-radius: 4px 0 4px 4px;
+      box-shadow: 0 3px 10px rgba(0, 0, 0, 0.20);
+    }
     .secondary-picker {
       border-bottom-right-radius: 0;
     }
-    .secondary-items {
-      display:block;
-    }
   }
 
+
   &.bordered,
   &:hover {
     .primary-item,
@@ -25,15 +44,18 @@
     }
   }
 
-  &.dropdown-btn-emphasis {
+  &.btn-emphasis {
     .primary-item,
     .secondary-picker,
     .only-item {
       .btn.btn-emphasis;
     }
+    .primary-item {
+      border-right:0;
+    }
   }
 
-  &.dropdown-btn-text {
+  &.btn-text {
     .primary-item,
     .secondary-picker,
     .only-item {
@@ -97,15 +119,13 @@
       white-space:nowrap;
     }
     border: 1px solid rgba(0, 0, 0, 0.15);
-    border-radius: 4px 0 4px 4px;
-    box-shadow: 0 3px 10px rgba(0, 0, 0, 0.20);
     z-index: 2;
     background-color: @background-primary;
     line-height: 14px;
     position: absolute;
     right: -1px; // -1, because of the border above
     white-space:nowrap;
-    display:none;
+    visibility:hidden;
 
     .menu {
       .footer-container,
@@ -168,7 +188,7 @@ body.platform-win32 {
     .secondary-items {
       border-radius: 0;
     }
-    &.dropdown-btn-emphasis {
+    &.btn-emphasis {
       .primary-item,
       .secondary-picker,
       .only-item {
@@ -184,7 +204,7 @@ body.platform-win32 {
         }
       }
     }
-    &.dropdown-btn-text {
+    &.btn-text {
       .primary-item,
       .secondary-picker,
       .only-item {