open relative links on click in preview, fixes #85

Author: tlnagy

lib/markdown-preview-view.coffee

@@ -99,6 +99,9 @@ class MarkdownPreviewView extends ScrollView
         @css('zoom', zoomLevel - .1)
       'markdown-preview:reset-zoom': =>
         @css('zoom', 1)
+      'click': (event)=>
+          event.stopPropagation()
+          @followLink(event)
 
     changeHandler = =>
       @renderMarkdown()
@@ -253,6 +256,15 @@ class MarkdownPreviewView extends ScrollView
 
     true
 
+  followLink: (event)->
+    return false if @loading
+    if event.target.tagName == 'A' && event.target.protocol == 'file:'
+        activeFile = @getPath()
+        activeFileDir = path.dirname(activeFile)
+        clickedFile = event.target.getAttribute('href')
+        clickedPath = path.join(activeFileDir, clickedFile)
+        atom.workspace.open clickedPath, { split: 'left' }
+
   saveAs: ->
     return if @loading